M 51, also known as the Tourbillon galaxy (Whirlpool Galaxy in English) is a couple of galaxies located around 27.4 million light years in the constellation of Hunting dogs.
This famous couple is composed of a regular spiral galaxy massive whose diameter is estimated at 100 000 light years and a small irregular galaxy .
Spring star, it is one of the most famous galaxies of astrophotographers, with very pronounced colors and presenting beautiful nebulae, accentuated here by the joint use of a Halpha Hydrogen filter.
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Caldwell's catalog
Caldwell's famous catalog is a astronomical catalog grouping 109 star clusters , nebulae and galaxies, primarily intended for an audience of amateur astronomers.
Created by Sir Patrick Alfred Caldwell-Moore (1923-2012) at the end of the 20th century, this catalog is intended to be an extension of the very famous one put in place by Charles Messier in the 18th century.
​ Himself an amateur astronomer, especially recognized as a specialist in the observation of Moon, Patrick Moore is considered to be the person who has done the most for the benefit of astronomy to the British general public. Renowned BBC popularizer, he chose the Caldwell name of his ancestors to be used in his catalog with the initial C, and thus distinguish itself from the M usite with the Messier catalog: M1, M31, M 98, etc.
The catalog was first published in 1995 in the journal Sky & Telescope.
Indeed if the Messier catalog is frequently used by amateur astronomers as a list of deep sky objects interesting for observations, Moore noticed that it does not incorporate many bright deep sky objects. Additionally, he observed that Messier's catalog, compiled from observations in the northern hemisphere alone, excludes luminous deep sky objects in the southern hemisphere.
He quickly drew up a list of 109 objects, with reference to the number of objects in Messier's catalog (109 at the time) and with the aim of supplementing the latter with the most remarkable objects which did not appear there.
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As in that of its illustrious predecessor, Caldwell's catalog contains deep sky objects that are within reach of amateur telescopes. However, objects in the Caldwell catalog are listed in order of declination, while those in Messier's catalog are listed in order of discovery, which means that not all Caldwell objects are accessible from a single location on the globe.
In France, for example, only objects from Caldwell 1 to Caldwell 76 will be visible, then you will have to descend to the southern hemisphere to complete the observation of the objects in this catalog.
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As for the Messier catalog by 135 astrophotographers presented on this site, I contacted a large number of astrophotographers in order to collect enough images to illustrate these 109 objects by as many participants as possible, of all levels and all approaches.
In the end, 140 images, 1 drawing and 1 gif of 141 different astrophotographers were used this time. Indeed the objective was that each object have the exclusivity of a photographer and it was therefore necessary to collect nearly 300 images selected from thousands before organizing them with the 109 objects to achieve this end.
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The article, mainly intended for astrophotographers or neophytes in love with images of the sky, is deliberately purified without too many explanations, both on the objects (characteristics) and on the photographs (exifs). He is simply a visual reminder of the nature and morphology of Caldwell objects through highlighting the work of amateur astrophotographers around the world.
The brief descriptions will however allow people with little or no knowledge of astronomy to familiarize themselves with the basics (in addition to the "general" article presented on this site), and to connoisseurs to remember them if necessary. The descriptions were synthesized / cross-referenced from Wikipedia, Stellarium and Aladin data.
A link to the Astrobin gallery or the author's personal website is also available by clicking on the author's name.
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The different sensitivities and / or approaches to astrophotography of the contributors are the main richness of this article which shows the different ways of photographing a deep sky object and of processing the images. Perhaps, moreover, certain unknown objects will give ideas to astrophotographers for their list of objects to photograph, or that certain images will make them want to discover the work of the astrophotographer cited.
The telescopes or glasses as well as the cameras used were informed for each object in order to give an idea to the photographers about its accessibility and the possible photographic rendering depending on the material.
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In addition, a maximum of the images used have were chosen because of the amateur material used, in the continuity of the popularization objective of Patrick Moore.
Thus no selected image was made from professional data, but only by amateurs with amateur material. However, the flourishing offer of rental companies of high-end amateur telescopes, even semi-professional, remotely from Chile or other interesting sites, allows a good number of amateurs to access the most difficult objects or objects. '' image accessible objects with greater finesse and / or image quality.
It must also be recognized that certain Caldwell objects, as is the case with certain Messier objects, are rather difficult to access to achieve beautiful images without substantial instrumentation, mainly due to their small size requiring long focal lengths, therefore large telescopes, and the most stable sky possible to get the maximum perceptible details in the image.
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It should also be noted that the criterion of a rather scientific-oriented approach, or rather artistic-oriented, or both, was not retained in the choice of images. It is the same for the criterion of popularity or nationality of the astrophotographers presented. Of course being the author of the article it is undeniable that the choice of images was influenced by my own tastes but sometimes it is quite simply the extreme rarity of amateur images on certain objects that dictated the choice (only one amateur image found on the internet for some of them!).
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Finally, it should be mentioned that as navigation is optimized for computers, a loss of image quality is to be expected on smartphone and tablet and there will sometimes be presentation inconsistencies between the images and the text for a consultation on this type of medium. . The images will however be displayed in the order in which they are presented in the text but following it, rather than "opposite" or "below". Probably also that improvements will be made thereafter such as a menu to facilitate access to a precise entry in the catalog, an optimization if possible of the smartphone version, or any other avenue of improvement that could be collected!
Have a good trip!
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Caldwell 1
C 1, or NGC188, is a open cluster located very close to the North Celestial Pole, in the constellation of Cepheus at around 6,680 light years of solar system. This is one of the open clusters oldest known in the Milky Way since it is estimated that its 120 stars are at least 9 billion years old. Its apparent size of 25 minutes of arc , almost that of the Moon, gives a maximum real size considering its distance of about 22 light years.
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Photo: Bernard Michaud (Litobrit) made with Newton 250mm f / 3.6 + Moravian G3-16200
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Caldwell 2
C2, or NGC 40, the Bow tie Nebula, is a planetary nebula located in the constellation Cepheus . It measures approximately one light year of diameter.
Scientists estimate that within 30,000 to 40,000 years it will be gone, leaving only one white dwarf about the size of Earth.
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Pictures :
- opposite a high resolution image of Romain Chauvet produced in lucky imaging with Newton 560mm f / 4 + camera QHY290m + red filter
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- below an LRGB + HO image of Peter Goodhew made with LZOS 150/1200 telescope + Qsi 6120 camera
Caldwell 3
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C3, or NGC 4236, is a barred spiral galaxy seen from the edge and located in the dragon constellation about 11.1 million light years away of the Milky Way .
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Photo : Tommy Nawratil made with Newton 250mm f / 4 + Asi1600mm camera
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Caldwell 4
C4, or NGC 7023 the famous Iris Nebula, is a reflection nebula located at 1300 light years in the constellation of Cepheus .
The dusty material of the nebula surrounds a massive hot young star forming, and the dominant color of the nebula is blue, characteristic of dust grains reflecting the star's light.
In the center of the Iris certain grains of dust effectively transform the star's invisible ultraviolet light into visible red light.
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Dark obscuring clouds and molecular gas are strongly present in this region of Cepheus.
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Pictures :
- a close-up view by Yann Sainty with newton 200mm f / 4 + ASI2600MC camera
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- a large field of Rallyho with FSQ106 scope and ASI6200mm camera
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Caldwell 5
C5, or IC 342, is a intermediate spiral galaxy front view and located in the constellation giraffe about 11.4 million light years away of the Milky Way .
The surface gloss of IC 342 is very weak because it is located near the plane of our galaxy and hidden from our sight by clouds of gas and dust, so much so that it is sometimes called "the hidden galaxy".
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Photo: Bart Delsaert with Newton 400mm f / 3.75 + camera FLI16803
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Caldwell 6
C6, or NGC6543 the famous Cat's Eye nebula, is a planetary nebula located about 3600 light years away in the constellation Dragon , and estimated to be 1,000 years old.
The core of the nebula, with a diameter of 20 seconds of arc, is rather small but it has a very large halo of matter which was ejected by the star which generated it during its phase of red giant . This halo measures 386 arc seconds (5.8 arc minutes).
a binary system (double star) would be at the origin of the nebula. The dynamic effects of the two stars rotating in orbit around each other would indeed more easily explain its structure, which appears much more complex than most of the other known planetary nebulae.
The central star of NGC 6543 is a star of the type Wolf-Rayet , with a temperature of around 80,000 K.
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Photo: JF Bax with Newton 350mm f / 3.6 + Asi290MM & Asi1600MC camera
Caldwell 7
C7, or NGC 2403, is a intermediate spiral galaxy located in the constellation giraffe about 11.1 million light years away of the Milky Way .
It is part of the group of M81, who has nearly forty galaxies.
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Photo: Rémi Méré LRGB + Ha with Newton 200mm f / 5 + Atik 460 camera
Caldwell 8
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C8, or NGC 559, is a open cluster located 3700 light years in the constellation Cassiopeia .
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Photo: Thomas V. Davis with Newton 300mm f / 3.5 + SBIG11000 camera
Caldwell 9
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C9, or Sh2-155, is a diffuse nebula in the constellation Cepheus, located 2,400 light years away within a larger complex of emission, reflection and dark nebulae.
Known as the cave nebula, it is a region of ionized hydrogen with however an interesting signal although quite low in oxygen and ionized sulfur.
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Pictures :
- opposite a close-up in SHO by Destin Heilman with SV105mm telescope + QSI6120 camera
- below a large field showing the environment of C9 by Fred Lamagat with 72/400 telescope + asi 2600MC camera
Caldwell 10
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C10, or NGC 663, is a open cluster located in the constellation Cassiopeia . Its age is estimated at 20-25 million years.
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Photo: in this image by Maurice Toet , taken with Epsilon 180D + Canon 5Dmk2, Caldwell 10 is the largest cluster a little below the center. The area is particularly rich in open clusters.
Caldwell 11
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C11, or NGC 7635, also known as the Bubble Nebula, is a nebula about 10 light years in diameter located in the constellation of Cassiopeia .
Located near the open cluster Messier 52 , this nebula looks like a bubble.
It is formed by the stellar wind created by the star SAO 20575 at a speed of over 1,700 km / s. This very young (less than 4 million years old), very hot (around 35,000 degrees) and massive (20 to 40 times the solar mass ) is not in the center of the bubble because the expanding cloud meets a denser, cooler region on one side. It should explode in supernova in 10 to 20 million years.
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Pictures :
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- opposite a SHO image of Julien Fabre made with TSA120 telescope + Moravian G2-4000 camera
- below a large LRGB field by Alvaro Ibanez Perez produced with FSQ106 telescope + Atik 16200 camera, centered on Caldwell 11 and revealing the richness of this zone in H2 regions, open clusters, and dark nebulae.
Caldwell 12
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C12, or NGC 6946 nicknamed the galaxy of Fireworks , is a spiral galaxy almost front view. Straddling the constellations of Swan and of Cepheus , it is located at a distance of about 20 million light years.
It is one of the most prolific galaxies in the sky in terms of the rate of supernovae (approximately 10 times the rate of the Milky Way, which is all the more remarkable as our Galaxy contains twice the number of stars), which has earned it the nickname of the fireworks galaxy.
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Pictures :
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- a close-up view of Tim Gillespie made with a C14HD telescope + QHY 128C camera
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- a very large field by Nicolas Kizilian made with WO ZS66 telescope + Moravian G2-8300 camera (mosaic of 6 panels).
From left to right, we find the open cluster NGC6939, Caldwell 12, the dark nebula B150, the emission nebula SH2-129, the planetary nebula OU4, and finally the reflection nebula VdB140.
Caldwell 13
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C13, or NGC 457 also called "cluster of the Owl", is a very young open cluster located about 7,920 light years in the constellation of Cassiopeia . It has eighty stars and its age is estimated at 21 million years old.
Its apparent size is 20 minutes of arc , which given its distance, gives a maximum actual size of about 46 light years.
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Photo: Caldwell 13 and the planetary nebula SH2-188 by Robert Eder with Newton 130/650 and Canon 600dA cooled
Caldwell 14
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C14, the famous double cluster of Perseus, is composed of the two open clusters NGC884 and NGC869 located about 7000 light years away in the constellation of Perseus.
Aged 11 and 12 million years old respectively, they were born from the same interstellar cloud . The first contains a lot of young stars of spectral type B, in other words giant stars, while the second is essentially made up of white B stars or red M stars in the supergiant . Given their dimensions (around 100 light years each), about 200 light years actually separate these clusters.
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Photo: left of center image NGC869 and right NGC884, directed by Adam Landefeld with Epsilon 130d telescope and QHY 163m camera. Note the presence of ionized hydrogen over the entire field revealed by the long exposure times through a Halpha filter (red sky background).
Caldwell 15
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C15, or NGC 6826, is a planetary nebula located in the constellation of Swan to about 5,220 light years .
It is part of a class of planetary nebulae nicknamed "Blink Nebulae". These nebulae, like NGC 2392 , have the particularity of flashing when the observer alternates the observation between direct vision and indirect vision. In direct vision, by fixing the central star, the cloudiness which surrounds it seems to disappear. Then by observing the nebula in indirect vision, it appears very bright. If you repeat this eye movement several times, the nebula will literally blink.
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Photo: high resolution image by Stephane Gonzales (Exaxe) in lucky imaging with Newton 300mm + Neptune C-II camera (IMX464)
Caldwell 16
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C16, or NGC 7243, is a open cluster located at approximately 2,640 light years in the constellation Lizard.
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Photo : William Maxwell with telescope Meade Starfinder 8 "+ Canon T1i Full Spectrum
Caldwell 17
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C17, or NGC 147, is a spheroidal dwarf galaxy belonging to Local group, which also includes our galaxy.
2.2 million light years away and located in Cassiopeia , NGC 147 is a galaxy satellite of the Andromeda Galaxy and seems to form a couple with NGC 185 which is close enough to it for the two galaxies to interact gravitational direct.
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Pictures : the couple formed by Caldwell 17 (NGC147 on the right) and Caldwell 18 (NGC185 on the left), directed by Eric Coles with RH305mm f / 3.8 telescope + SBIG STXL 16200 camera
Caldwell 18
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C18, or NGC 185 is a spheroidal dwarf galaxy located in the constellation Cassiopeia, belonging to the local group, and distant 2.1 million light years.
Just like Caldwell 17 with whom it is in gravitational interaction, it is a satellite of the Andromeda galaxy.
NGC 185 is a Seyfert galaxy, namely a spiral galaxy characterized by an extremely bright and compact core which represents one of the largest sources of electromagnetic radiation known to the Universe, possibly due to the supermassive black hole at their center.
The Seyfert galaxies represent more than 5% of all the galaxies in the observable universe and form one of two important groups of so-called active galaxies , the other group being the quasars.
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Photo: Jean-Claude Mario with RC360mm f / 8 and CCD camera kaf16803
Caldwell 19
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C19, or IC5146 the famous Cocoon Nebula, is an emission nebula associated with an open cluster, located about 4000 light years away in the constellation Cassiopeia. It is an intense zone of star formation.
Photo: Marcel Drechsler with RASA 11 telescope and ASI1600mm camera
Caldwell 20
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C20, or NGC7000 the famous North American nebula, is an emission nebula located approximately 1,890 light years away in the constellation Cygnus.
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Pictures :
- a large SHO field with NGC7000 on the left, IC5070 the Pelican nebula on the right, and IC5068 below, made by Idir Saci with FSQ106 refractor and Moravian 16803 camera
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- a close-up SHO on "the wall" in NGC7000 made by Nicolas Puig with Newton 200/800 and asi1600mm camera
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- a very large field in natural colors of this rich region of the Milky Way, produced by Olly Penrice and Paul Kummer with FSQ106 + Atik11000 camera (mosaic of 9 panels)
Caldwell 21
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C21, or NGC 4449 is a irregular galaxy magellanic located in the constellation of Hunting dogs about 12.6 million light years away.
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A magellanic spiral galaxy is a type of spiral galaxy having only one spiral arm and which is usually small.
This type of spiral galaxy takes its name from Large Magellanic Cloud, famous galaxy visible from the Southern Hemisphere.
As for spirals, there are three major types of magellanic spiral galaxies depending on whether they are regular (without bar), crossed out (with bar) or intermediaries.
Then comes this class of irregular magellanic galaxies of which Caldwell 21 belongs, which have the beginning of a spiral arm.
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Photo: Christoph Lichtblau with C11 edgeHD telescope + 6200mm ASI camera
Caldwell 22
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C22, or NGC 7662, nicknamed the Blue snowball, is a planetary nebula located 5600 light years away in the constellation Andromeda.
Its gaseous envelope measures nearly one light year in diameter, and the temperature of the central white dwarf at the origin of the nebula exceeds 75,000 K.
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Photo: shot by Sascha Schueller & Ralf Kreuels in short exposures with Newton 400mm f / 4 + atik460 in long exposures and c11 + ASI 178mm in short exposures
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Caldwell 23
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C23, NGC 891, is a spiral galaxy side view and located about 29 million light years away in the constellation Andromeda . It measures about 100,000 light years, the same size as our Milky Way.
NGC 891 is the very prototype of the galaxies seen from the edge, and the median plane is here crossed by a thick band of dust which seems to split the galaxy into two symmetrical parts.
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Pictures :
- opposite NGC891 in the tail of comet Lovejoy in 2014 by Damian Peach with FSQ106 refractor and SBIG STL11000 camera
- below a close-up of Fabio Mirra with RC8 telescope and Moravian G2-4000
Caldwell 24
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C24, or NGC 1275, is a lenticular galaxy giant located in the constellation perseus about 240 million light years away of the Milky Way .
This Seyfert-type galaxy is located at the center of the Perseus cluster (Abell 426) of which it is the main member.
NGC 1275 actually consists of two galaxies, one central and the other of the HVS type, (high velocity system) which is in front of NGC 1275 and moves towards it at a speed of 3000 km / s . It is believed that this HVS galaxy, which is located at least 200,000 light years from NGC1275, will eventually merge with this one.
NGC 1275 also houses a supermassive black hole whose mass is about 340 million solar masses.
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Pictures :
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- opposite a close-up view by Vlad Onoprienko with MK 9 "telescope and QSI 640i camera (author's crop)
- below Caldwell 24 within the Perseus cluster by Jason Guenzel with Celestron Edge HD 800 telescope and ASI 1600mm camera
Caldwell 25
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C25, or NGC 2419, is a globular cluster located in the constellation of Lynx about 290,000 light years away .
NGC 2419 is called the "intergalactic wanderer" because it was long believed due to its great distance that it was not in orbit around the Milky Way .
Its orbit takes it to a greater distance than that of Magellanic clouds, our neighboring galaxies, so it is much further from the bulb of the Milky Way than other globular clusters.
It is now considered that it is linked to our galaxy by gravity and that its revolution around the Milky Way is about 3 billion years.
As for the globular cluster Omega Centauri (NGC 5319), it was hypothesized that NGC 2419 could be what remains of a spheroidal dwarf galaxy dissociated and captured by the Milky Way.
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Photo: Albert Van Duin with Newton 400mm f / 4 and QSI 583 camera
Caldwell 26
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C26, or NGC 4244, is a spiral galaxy seen from the side and located in the constellation of Hunting dogs about 11 million light years away .
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Photo: Jens Zippel with Newton 250/1000 and ASI 1600mm camera
Caldwell 27
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C27, or NGC6888 the Crescent Nebula, is a emission nebula located in the constellation Cygnus , about 5,000 light years .
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She comes from the rapids stellar winds created by the star Wolf-Rayet WR 136 which pushes the matter resulting from slower winds ejected by this same star when it was younger and smaller (of type red giant ) 400,000 years ago.
The shock front generates what is called a Wolf-Rayet bubble .
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Pictures :
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- opposite a very close-up shot by Rocco Sung with a 17 "CDK telescope (focal length 2939mm) and an Apogee U16000 camera
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- below a very large SHO field of this rich region of the Swan, realized by Pavel Pavlov with a canon lens of 200mm f / 2.8 and ZWO 1600mm camera, and extending from the crescent nebula at the top left to the nebula of the tulip lower right.
Caldwell 28
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NGC 752 or Caldwell 28 is a open cluster located about 1490 light years in the constellation Andromeda .
Its age is estimated at 1.34 billion years and there are 258 stars.
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Photo: Caldwell 28 and a multitude of distant galaxies in the background, realized by Herbert Walter with newton 250/1000 and Moravian G2-8300 camera
Caldwell 29
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NGC 5005 is a intermediate spiral galaxy located in the constellation from Hunting dogs about 43 million light years away of the Milky Way . It is an active Seyfert-type galaxy and it is in interaction with its beautiful neighbor NGC 5033.
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Photo: NGC5033 (left) and NGC5005 (right) by Arturas Medvedevas with Newton 130/650 and SX694 camera
Caldwell 30
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NGC 7331 is a barred spiral galaxy located approximately 42.4 million light years of the Earth in the constellation Pegasus .
With a diameter of about 100,000 light years, it is the main component of a collection of galaxies known as the Deer Lick group , although the other galaxies in this set are about 10 times farther away than it is.
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Pictures :
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opposite a close-up of Caldwell 30 and his Deer Lick group realized by John Hayes with C14 edhe HD telescope and FLI 16803 camera
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below a large field of Jérome Rudelle realized with newton 200/800 and camera Morian G2-4000. Stephan's famous quintet, a set of 5 distant interacting galaxies, is visible on the left side of the image, as well as a multitude of galaxies populating the sky background of this rich area of Pegasus.
Caldwell 31
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C31, or IC 405 the Flaming Star Nebula, is an emission and reflection nebula located about 1,500 light-years away in the constellation Coach.
It surrounds the irregular variable star AE Aurigae which has the particularity of belonging to the class of stars say "fugitive". Indeed it is estimated that she was born in the Orion Nebula about 2.7 million years ago before completing a long journey that brought him to this region of the coachman. It then gave birth to this nebula by ionizing the gas present, producing the color red due to the majority presence of hydrogen.
The blue parts are due to the reflection of the star's blue light on the surrounding dust.
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Pictures :
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- opposite a large SHO field of the Ciel Boréal team showing from left to right IC405, IC410 and IC417, and produced with RH200 telescope and G4-16000 camera
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- below a close-up of IC405 in natural colors (LRVBH) by Stefan Harry Thrun with WO GT81 refractor and 1600mm asi camera
Caldwell 32
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C32, or NGC 4631 the Whale Galaxy, is a barred spiral galaxy seen from the side and located in the constellation of Hunting dogs about 28 million light years away of the Milky Way .
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It interacts with its companion the galaxy NGC 4627, as well as with NGC 4656 the Hockey Stick Galaxy, located about half a degree to the southeast.
In addition, NGC 4631 is part of a group of galaxies which bears his name and has at least 14 members.
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Pictures :
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- opposite a close-up view of NGC 4631 and its companion NGC 4627, the couple also referred to as Arp 281, produced by Chad Leade with C8 edge HD telescope and ASI 294mm camera
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- below comet C / 2020 R4 (Atlas) heading towards the Hockey Stick galaxy and the Whale galaxy, produced by Terry Hancock with Epsilon 130 telescope and QHy600 + Epsilon 180 camera and QHY410 camera
Caldwell 33
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C33, or NGC 6992, designates the northeastern region of the gigantic Swan Lace complex.
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The Swan Lace (Cygnus loop or SNR G074.0-08.6) form a persistent of supernova located in the constellation Cygnus and whose explosion dates back to ten thousand years.
This one object is very large (about ten square degrees) and very fragmented, which has only recently received a designation that applies to the entire object. We also find the Swan Lace in the Sharpless catalog under the designation Sh2-103.
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NGC6992 also called "the big lace" is the brightest part of this afterglow. It has the shape of a comma composed of very fine filaments extending over 1.2 ° for a width of the order of ten minutes of arc .
Note that the widest part of Caldwell 33 alone bears the designation NGC 6995
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Pictures :
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- opposite the laces of the entire swan by MatthieuTequi with Askar fra400mm telescope and ASI2600mm camera (mosaic of 2 panels): Caldwell 33 is on the left
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- below Caldwell 33 by Alan Pham with Stellarvue SV4 telescope and ASI 1600mm camera​
Caldwell 34
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C34, or NGC 6960 called the small lace, designates the southwestern part of the Swan Lace complex, opposite to Caldwell 33.
North of the bright star 52 Cygni, the Little Lace consists of a filament comprising two main strands, extending for almost half a degree. On the other side of the star, the filament flares out in a south-easterly direction around three main strands.
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Pictures :
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-see Caldwell 34 by Dave Boddington with SW150 Esprit + SX46 (HRVB) and SW100 Esprit + ASI1600mm (HO) goggles
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- below a large field of the Milky Way by David Malattia made with 135mm f / 2 lens and defiltered Sony A7s digital camera (mosaic of 8 panels): the Swan lace in the lower part of the image
Caldwell 35
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C35, or NGC 4889, is a elliptical galaxy giant located in the constellation of the Berenice's hair about 296 million light years away .
It is located at the heart of the Coma Cluster, or Berenice's Hair Cluster (Abell 1656), which has more than 1000 galaxies and is also the brightest galaxy in a world. group of galaxies which bears his name and has at least 18 members.
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Photo: the central region of the coma cluster by Chen Wu made with TOA130 telescope and ASI 6200mm camera: of the two giant ellipticals in the center, Caldwell35 is the lower one, the upper one being NGC4874.
Caldwell 36
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C36, or NGC 4559, is a intermediate spiral galaxy located in the constellation of Berenice's hair about 37 million light years away of the Milky Way .
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Photo: Steve Milne with TEC140 refractor and QSI690 camera
Caldwell 37
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C37, or NGC 6885, is an open cluster located approximately 1950 light-years away in the constellation Little Fox.
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Photo: Bernhard Zimmermann with newton 200/1000 and cannon 60dA (NGC6885 is the cluster in the lower part of the image, NGC6882 being that of the upper part)
Caldwell 38
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C38, or NGC 4565, is an extensive spiral galaxy seen through the slice located in the constellation of Berenice's hair . It is at a distance between 38 and 56 million light years of the Milky Way .
Due to the very thin appearance of its disk, it is also nicknamed the Needle Galaxy.
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Photo: Anthony Husson with Newton 250/1000 and asi 294mm
Caldwell 39
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C39, or NGC 2392 The Eskimo Nebula is a planetary nebula bipolar sporting a double shell and located approximately 3750 light years in Gemini.
It is known for the exceptionally high speed of its internal shell, around 90 km / s, and the existence of a rapid bipolar flow with a radial speed approaching 200 km / s.
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Photo: Carsten Dosche with C9.25 telescope and EMCCD Andor LucaR camera in short exposures
Caldwell 40
C40, or NGC 3632, is a lenticular galaxy located in the constellation Leo about 68 million light years away.
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photo: Gary Imm with TOA130 refractor and 1600mm asi camera
Caldwell 41
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C41, called Les Hyades, is the open cluster closest to Solar system (151 light years), made up of 300 to 400 stars.
A third of the confirmed members of this cluster are in the halo and are probably on the verge of escaping the force of its gravity.
Indeed, most open clusters have a relatively short lifespan of the order of a few tens of millions of years because the stars they shelter, formed as a result of the contraction of a cloud of gas and dust, disperse over time under the action of tidal forces and end up no longer being linked to each other by gravity. Only the most massive open clusters, located at great distances from the galactic center , can survive for longer periods of time. Thus at the time of its formation the Hyades cluster probably contained a greater number of stars than today. Its age is estimated at 625 million years.
Note that the Hyades cluster and the crèche cluster M44 have the same age, the same proper movement and the same metallicity, and that they come from the same region of the galaxy and therefore have a common origin.
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Pictures :
- opposite a very large field by Amir H. Abolfath realized with Sigma Art 85mm and Canon 6D lens with among others: Hyades and Pleiades
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- below by Alberto Pisabarro with 135mm f / 2 and QSI 583wsg
Caldwell 42
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C42, or NGC 7006, is a globular cluster located about 135,000 light years away in the constellation Dolphin . Like most globular clusters it is part of the galactic halo .
Its apparent diameter is only 1.5 arc minutes.
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Photo: Caldwell 42 and many distant galaxies in the background, by Rocinante with newton 254mm f / 4.7 and orion DSI3 mono camera
Caldwell 43
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C43, or NGC 7814, is a spiral galaxy side view and located approximately 53 million light years in the constellation of Pegasus .
It is also called the "little sombrero" because of its resemblance to the famous Sombrero M104 galaxy.
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Photo: Peter Csordas (Xordi) with C8 edge HD telescope and atik one 6.0 camera
Caldwell 44
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C44, or NGC 7479, is a barred spiral galaxy with a very marked star bar seen from the front, which allows you to admire its structure.
It is located in the constellation Pegasus at a distance of 105 million light years , and has an apparent angular dimension of 4.1 by 3.2 arc minutes.
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Photo: a collaboration of Colin McGill , Detlef Hartmann, Francesco Corrao, Aldo Grassi and Lorenzo Siciliano made by mixing data from three amateur telescopes: RC 8 "+ Atik 460ex, Newton 17.5" + Sbig ST10XME, C11 + Sbig ST8XME
Caldwell 45
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C45, or NGC 5248, is a intermediate spiral galaxy located in the constellation of Bouvier about 52 million light years away of the Milky Way .
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Photo: Arnaud Peel with Newton 300mm f / 4 and ASI 1600mm camera
Caldwell 46
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C46, or NGC 2261, is a reflection nebula located at approximately 2,500 light years in the constellation of the Unicorn and who spans about 2.2 light years .
Although it was discovered by William Herschel in 1783, it is called the Hubble Variable Nebula because it was the object of the first light of hale telescope from the Mont Palomar observatory in 1949, and that it is Edwin Hubble who operated the telescope.
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She and is lit by R Monocerotis , T Tauri type variable star .
The variable brightness of NGC 2261 would not come only from the brightness variable of R Monocerotis: a proposed model invokes dense clouds of dust that would periodically obstruct the light coming from the star.
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Photo: on this close-up of Caldwell 46, Giovanni Paglioli mixed several data using his RC360mm telescope + FLI4710 camera to image the nebula, then his Epsilon 130 telescope + QSI683wsg camera to image the nebulosities of ionized hydrogen (red) that surround him
Caldwell 47
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C47, or NGC 6934, is a globular cluster located at approximately 50,000 light years in the constellation Dolphin.
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The globular clusters roam the halo of our galaxy, the Milky Way . Linked by gravity, these spherical groupings of several hundred thousand stars are older than the stars of the galactic disk. The age of Caldwell 47 is estimated to be around 10 billion years old.
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Photo: a very close-up shot by Bob Franke with 12.5 "RC telescope and SBIG ST7 camera
Caldwell 48
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C48, or NGC 2775, is a spiral galaxy located about 61 million light years away in the constellation Cancer.
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Photo: Kaori Iwakata with Newton 210mm f / 6 and SBIG ST8-XME camera
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Caldwell 49
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C49, The Rosetta Nebula, is a vast nebula in transmission (region H2) located about 4,700 light years into the constellation of the Unicorn .
It is an active star nursery relatively close and due to its vast size several objects from the NGC catalog can be found there:
- NGC 2237: the western part of the nebula
- NGC 2238 : another part of the Rosette
- NGC 2239 (or NGC2244): a very young open star cluster that ionizes the hydrogen in the nebula, giving it its red tint.
- NGC 2246 : another part of the Rosette
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Pictures :
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- Opposite C49 in SHO by Bogdan Borz with 115mm f / 7 + ASI1600mm refractor
- Below C49 in wide field by Marie Blind with 61 EDPH refractor and Canon 6D defiltered
Caldwell 50
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C50, or NGC2244, is the open cluster located in the heart of the Rosetta Nebula Caldwell 49 and which ionizes the gases of this nebula.
Located at approximately 4,710 light years in the constellation of the Unicorn, its age is estimated to be around 8 million years old .
Its apparent size is 24 minutes of arc , which, given its distance, gives a maximum actual size of about 33 light-years.
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Photo: Thomas Lelu with Newton 10 "f / 3.6 and Moravian G2-4000 camera and SHO filters
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Caldwell 51
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C51, or IC 1613, is a galaxy irregular dwarf (which combines the characteristics of irregular galaxies and dwarf spheroids) located about 2.36 million light years away in the constellation Whale. Member of our Local band , she is probably satellite of the Andromeda galaxy M31 .
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Photo: Jan Sjoerd de Vries with APM 152/1206 refractor and QSI683wsg camera
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Caldwell 52
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C52, or NGC 4697, is a elliptical galaxy located in the constellation of the Virgin about 57 million light years away. It's a active galaxy with a low-light core.
NGC 4697 is part of a group of galaxies which bears his name and has at least 19 galaxies. This group is part of the Virgo cluster.
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Photo: David Cheng with Epsilon 130d telescope and Atik one 9.0 camera. Caldwell 52 is in the upper right, and the galaxy in the center is NGC4731
Caldwell 53
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C53, or NGC 3115 also called the Spindle Galaxy, is a lenticular galaxy located in the constellation Sextant about 30 million light years away of the Milky Way .
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Photo: Frank Colosimo with C11 Edge HD and SBIG STL11000 camera
Caldwell 54
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C54, or NGC 2506, is a open cluster located approximately 11,300 light years in the constellation of the Unicorn .
His age is estimated at 1.1 billion years old and its apparent size is 12 arc minutes , which given the distance gives a maximum actual size of about 39 light years.
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Photo: David A. Churchill with AP 175 EDF telescope and SBIG STT8300 camera
Caldwell 55
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C55, or NGC 7009, is a planetary nebula located approximately 4,320 light-years away in the constellation Aquarius .
Discovered by William Herschel in 1782, she is not the first planetary nebula discovery, but it is the first to be identified as such. Herschel then proposed the term "planetary nebula" because of the shape of these often circular and bluish objects that evoke the planet. Uranus , which he had just discovered in 1781.
Caldwell 55 is called the Saturn Nebula because of its general shape which evokes the planet Saturn.
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Photo: Lukasz Sujka with Newton 250/1200 and 178mm ASI camera (short exposures)
Caldwell 56
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C56, or NGC 246 the Skull Nebula, is a planetary nebula located at approximately 1600 light years of the Earth in the constellation of the Whale . Its size is about 2.1 light years.
The white dwarf HIP 3678 at its center is part of a triple star system.
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Photo: Scott M. Stirling with CDK17 telescope and FLI16200 camera
Caldwell 57
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C57, the Barnard galaxy also referred to as NGC 6822 and IC 4895, is a barred irregular galaxy of Local group located about 1.63 million light years away in the constellation Sagittarius. It is one of the galaxies closest to ours and its composition and morphology are similar to that of Small Magellanic Cloud .
It only contains about 10 million stars (compared to 100 to 200 billion in the Milky Way), the majority of which are young stars.
Photo :
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- opposite large field with surrounding IFN nebulosities, Rabbit Zhang with fsq106 telescope and Moravian G3-16200 camera
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- below close-up of Casey Good with 17 "CDK telescope and FLI16803 camera
Caldwell 58
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C58, or NGC 2360, is a open cluster located about 6,150 light years in the constellation of the Big Dog . Its apparent size is 14 arc minutes , which, considering the distance, gives a maximum actual size of about 25 light years.
It was discovered by the astronomer German Caroline Herschel in 1783 and it is in his honor that it is called the Caroline cluster.
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Pictures :
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- opposite Jim Thommes with Megrez 80mm refractor and Artemis 285 camera
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- below a large field of Matt Harbison centered on the Nebula of the Seagull and allowing to locate Caldwell 58 in the lower right corner. Made with fsq106 telescope and QHY600 camera
Caldwell 59
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C59, or NGC 3242, is a planetary nebula located approximately 4,780 light years away in the constellation of the Hydra . Its apparent diameter is about 1.1 arc minutes in the visible range, but extends up to 5.6 arc minutes in the infrared.
Caldwell 59 is also given the name "Phantom of Jupiter" or even the Eye nebula.
A strange feature of this planetary nebula is the presence of two red lobes at the poles of the nebula's core (not visible on amateur images). These lobes are believed to be younger than the nebulae and to move faster than the rest of the gases. We do not yet know their origin and exact nature.
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Photo: Terry Robison with RC 10 "telescope and SBIG STL11000M camera
Contrary to what one might think there is no link established with the nebulosity of ionized hydrogen and oxygen on the left of the NP.
Caldwell 60
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C60, or NGC4038, is a barred spiral galaxy which forms with Caldwell 61 (NGC4039) the very famous pair of Antennae galaxies. This pair of interacting galaxies is located about 75 million light years in the constellation of Raven and the two galaxies are of type magellanic .
The Antennae galaxies are the result of a galactic collision and the two large star-shaped outgrowths, of gas, and of dust ejected out of their galaxy during this collision resemble the antennas of a insect .
In several million years, the galactic nuclei of NGC 4038 and NGC 4039 will collide and become a single nucleus surrounded by stars, gas and dust. Some observations and simulations suggest that these galaxies will eventually merge into elliptical galaxy .
This will probably also happen to the Milky Way when it collides with our neighbor the Andromeda galaxy .
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NGC 4038 and NGC 4039 are also part of a group of galaxies which has at least 27 members and bears the name of group of NGC 4038 .
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Photo: Greg Turgeon with CDK17 and FLI16803 camera (in this image Caldwell 60 is the top galaxy and Caldwell 61 the bottom galaxy)
Caldwell 61
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C61, or NGC4039, is an ordinary spiral galaxy which forms with Caldwell 60 (NGC40 38) the very famous pair of Antennae galaxies. (see Caldwell 60 description).
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Photo: Yizhou Zhang with TOA130 refractor and ASI6200mm camera. Note the presence of many galaxies in the sky background of this area, and in particular in the lower right corner the barred spiral galaxy magellanic NGC4027.
Caldwell 62
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C62, or NGC 247, is a intermediate spiral galaxy , therefore weakly barred, located about 6.82 million light years in the constellation Whale .
It is part of the Filament of the Sculptor , a group of galaxies located near the Local group, the group housing the Milky Way .
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Photo: Wellerson Lopes with and ASI1600mm camera. The cluster of galaxies on the right side of the image is called the Burbidge Range and is located 300 million light years away.
Caldwell 63
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C63, or NGC 7293 the famous Helix Nebula (Helix), is a planetary nebula located in the constellation of Aquarius. Located about 650 light years from the Earth , it is one of the closest planetary nebulae. It is presented as two intertwined rings and its strong resemblance to a human eye has earned it the nickname "the eye of God".
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Photo: image SHO by Juan Filas with Newton 250 f / 4 and ASI1600mm
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Caldwell 64
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C64, or NGC 2362, is a very young open cluster located about 4530 light years in the constellation of the Big Dog. It is about 8.2 million years old and has some 500 stars.
The apparent size of the cluster is 6 arc minutes , which given its distance gives a maximum actual size of about 7.9 light years. The central star, Tau Canis Majoris is an O-type supergiant
NGC 2362 is nearby and in physical relation to the giant nebula Sh2-310, one of the largest H2 regions in the Milky Way, which is at the same distance.
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Photo: NGC2362 and the VdB96 reflection nebula by Velimir Popov & Emil Ivanov with Newton 300mm f / 3.6 and SBIG STL11000 camera
Caldwell 65
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C65, or NGC253 the Sculptor Galaxy, is a intermediate spiral galaxy located about 10.8 million light years away in the constellation of Sculptor . It is an active Seyfert-type galaxy with a startling star formation (high birth rate).
Located in the center of Filament of the Sculptor , which is one of the galaxy groups closest to the Milky Way, she is the main member.
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Photo: Fluorite Zhu with TSA120 refractor and atik one 6.0 camera
Caldwell 66
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C66, or NGC5694, is a globular cluster located approximately 114,000 light years from the solar system in the constellation Hydra. 13 billion years old, it is one of the oldest in the Milky Way.
Its particular chemical composition suggests an extragalactic origin before being captured by our galaxy.
The apparent size of Caldwell 66 is 3.6 arc minutes.
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Photo :
- On 02/11/18, Mike Keith rents a 500mm remote telescope from Chile to photograph the passage of the Tesla roadster (launched 02/07/18) near Caldwell 66 (bottom of the image below)
- On 02/19/18 he repeats the operation while the Rover is much closer to Caldwell 66 (by perspective of course) and realizes with his images the gif opposite. The Rover is then 3.7 million km from Earth.
Caldwell 67
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C67, or NGC 1097, is a barred spiral galaxy located in the constellation Fourneau about 58 million light years from the Milky Way. She is the brightest and largest galaxy in a group of galaxies of at least 5 members that bears her name, and she also forms with one of these members named NGC1097A the pair of interacting galaxies named ARP 77 .
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Photo: Lee Borsboom with Newton 200mm f / 4.5 and QHY 178M camera. The elliptical dwarf galaxy NGC1097A is just 3.3 arc minutes or about 53,000 light years from the galactic center of Caldwell67, with which it is in gravitational interaction.
Caldwell 68
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C68, or NGC 6729, is a reflection-emission nebula located in the constellation Southern Corona just 400 light years away, making it one of the star-forming regions closest to the Sun.
Caldwell 68 is a portion of the Southern Corona Large Molecular Cloud, and it is a variable nebula that shows irregular variations in its brightness and shape.
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Photo :
- opposite Caldwell 68 and the globular cluster NGC 6723, by Matthew Sole with Newton 200/800 and ASI1600mm camera
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- below the large molecular cloud of the southern crown produced by Wei-Hao Wang with Epsilon 180ED and Nikon D800
Caldwell 69
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C69, or NGC 6302 (also called the Insect nebula or the Butterfly nebula), is a planetary nebula bipolar located about 3400 light years into the constellation of Scorpio .
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Its structure is one of the most complex ever observed in a planetary nebula. It can be roughly described as being bipolar with two primary lobes, although there is some evidence to support the existence of a second pair of lobes which may have belonged to a previous phase of mass loss. A dark band crosses the middle of the nebula, obscuring the central star at all wavelengths.
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The spectrum of NGC 6302 reveals that its central star is one of the hottest in our galaxy, with a surface temperature exceeding 200,000 K, indicating that the star from which it was formed must be very large.
This star was only recently discovered (due to its high temperature, emitting only in UV, and the disk of dust strongly absorbing light from the central region) and its current mass is around 0, 64 times the mass of the sun (the original mass was much larger, but most of it was ejected during the event that generated the planetary nebula). Its brightness and temperature indicate that it has ceased all nuclear activity and is on its way to becoming a white dwarf, cooling down at an estimated rate of 1% per year.
It is surrounded by a particularly dense equatorial disk, made up of gas and dust. This disc would be at the origin of the bipolar structure, similar to an hourglass, of the star's releases. This bipolar structure exhibits many interesting features common to planetary nebulae, such as ionization walls, nodes, and sharp edges at the lobes.
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Photo: Los Calvos Observatory team with CDK 12.5 "telescope and Moravian G4-16000 camera
Caldwell 70
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C70, or NGC 300, is a spiral galaxy located about 6.5 million light years of the Earth in the constellation of Sculptor . It spans about 36,000 light years and it appears to be in gravitational interaction with the galaxy NGC55 (Caldwell 72).
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Photo: Ray Johnson with Newton 250/1000 and ASI 1600mm camera
Caldwell 71
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C71, or NGC 2477, is a open cluster located approximately 3,990 light years into the constellation from the Stern . It is estimated to be 705 million years old, and its size of around 23 light years gives it an apparent size of 20 arc minutes.
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Photo: Andrealuna Pizzetti with Televue NP127 telescope and FLI16803 camera (Caldwell 71 on the left of center and the open cluster NGC 2451 on the right)
Caldwell 72
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C72, or NGC 55, is a side-view magellanic spiral galaxy located approximately 5.87 million light years from Earth in the constellation Sculptor. Its diameter is about 60,000 light years and it appears to be in gravitational interaction with the galaxy NGC 300 (Caldwell 70).
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Photo: Vadim Kozatchenko with Newton 500m f / 3.8 and FLI 16803 camera
Caldwell 73
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C73, or NGC 1851, is a globular cluster located about 39.5 million light years in the constellation Dove . Its age is estimated at 9.98 billion years.
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Photo: Fabian Rodriguez Frustaglia with Meade LX8550 12 "telescope and SBIG ST-8300C camera
Caldwell 74
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C74, or NGC 3132, is a planetary nebula located in the constellation Sails at around 2000 light years of the solar system.
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Nicknamed the Eight-Shard Nebula or the Southern Ring Nebula (because of its resemblance to the M57 Ring Nebula), its diameter is approximately 0.93 light year and its apparent size of 1.6 x 1 arc minute.
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The two stars in the center of NGC 3132 form a binary system whose less luminous member is the white dwarf which gave birth to this nebula. This central star, whose temperature reaches 100,000 K, has now finished blowing its outer layers of gas and makes the nebula shine by emitting its intense ultraviolet radiation.
The other star is in the last stages of its evolution and it too could give birth to its own nebula.
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Pictures :
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- opposite Kfir Simon used data from two large remote telescopes: a T1000 f / 6.8 telescope in Chile and an RC 400mm F8 in Namibia to obtain a detailed view of Caldwell 74, whose small size requires the use of substantial instruments.
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- below a large field realized with material more accessible by Capella Ben , with C9.25 and camera ASI071MC, where the resemblance with M57 is speaking.
Caldwell 75
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C75, or NGC 6124, is an open cluster located approximately 18,600 light-years away in the constellation Scorpio.
Its apparent size is 29 arc minutes, roughly the size of the full moon.
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Pictures :
- opposite a close-up view of Rodney Watters made with TSA120 telescope and QSI 683WS 8 camera
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- below an image of the Milky Way crossing the constellation Scorpio made in Chile by Thibault Sandre with a Samyang 35mm f / 1.4 lens and Canon 1100D camera allowing us to locate Caldwell 75 starting from the scorpion towards the constellation Wolf .
Caldwell 76
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C76, or NGC 6231, is an open cluster of the constellation Scorpio near the star Zeta Scorpii and NGC 4628 the shrimp nebula.
Located about 5,900 light years away, this cluster is about 3.2 million years old.
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Pictures :
- opposite a large field by Josep M. Drudis centered on IC 4628 the shrimp nebula (Prawn nebula) made with TOA130 f / 5.7 refractor and SBIG STX16803 camera
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- below a close-up view of the cluster by Connor Matherne performed with TOA 150 refractor and FLI16200 camera
Caldwell 77
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C77, or NGC5128 Centaurus A, is a lenticular galaxy located at approximately 12.4 million light years of the Milky Way in the constellation of Centaur . At this distance and with a maximum size in visible light equal to 25.7 arc minutes , we can deduce that the diameter of Centaurus A is about 90,000 light years .
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It is one of the radio galaxies closest to Earth and therefore its active galactic nucleus has been particularly studied by professional astronomers. Indeed, in radio waves, Centaurus A is one of the brightest and largest objects in the sky extending almost 20 times the apparent diameter of the Moon .
Centaurus A is described as having a morphology particular . Seen from Earth, the galaxy looks like a lenticular galaxy Where elliptical with a superimposed strip of dust. This strip of dust that crosses the galaxy is actually a disk seen from the side made up of a population of stars rich in metals , nebulae and dust clouds.
The unusual morphology of the galaxy is generally explained as being the result of a fusion between two smaller galaxies.
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Centaurus A's enormous energy output comes from gas falling into the central supermassive black hole. Some of this material is again ejected in two opposing jets at a considerable fraction of the speed of light. These jets interact with the surrounding gas and then affect the rate of star formation in the galaxy.
It is further estimated that more than 1,500 globular clusters surround NGC 5128.
Finally, Centaurus A is the main galaxy of the group of galaxies that bears its name and has at least 8 galaxies.
Photo: image produced by Rick Stevenson from Martin Pugh data acquired with CDK 17 "telescope and SBIG STXL 11002M camera. Note the visible part of the jet of matter emanating from the heart on the right of the image.
Caldwell 78
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NGC 6541 is a globular cluster located about 22,830 light years in the constellation of the Southern Crown. Its apparent size is 15 arc minutes.
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Photo: Tom Fowler with CDK 250mm telescope and QSI583wsg camera
Caldwell 79
C79, or NGC 3201, is a globular cluster located approximately 16,000 light years from the Sun in the constellation Sails and about 10 to 12 billion years old.
Caldwell 79 has a very low concentration of stars at its center and its radial speed is abnormally high, from 482 km / s to 494 km / s depending on the source, more than any other known cluster.
It corresponds to a relative speed with respect to the center of the Milky Way ( "Peculiar velocity" ) of 240 km / s which, although high, remains lower than the speed required to be released of the attraction of the Milky Way.
Note also that we discovered the 1st black hole in a globular cluster at the center of Caldwell 79.
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Photo: Paul Montague (DiscoDuck) with RC 200mm telescope and QHYCCD 8 camera
Caldwell 80
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C80, or NGC 5139 the famous Omega Centauri, is a globular cluster located approximately 15,700 light years from the Sun in the constellation Centaur.
With a diameter of about 253 light years, it is the largest globular cluster known to exist in the Milky Way. It is estimated to contain around 10 million stars and its mass is equivalent to 4 million solar masses, which also makes it the most massive known globular cluster in our galaxy.
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Different in several ways from other globular clusters in the Milky Way, it has been hypothesized that it could be the remains of a dwarf galaxy disturbed by the gravity of the Milky Way.
In fact, the density of stars in the central region is so great that it is estimated that there is only a distance of 0.1 light-years between each of them. On the other hand, the stars of Omega Centauri present a great diversity of age and metallicity which indicates that several generations of stars have followed one another in the cluster while in general, the stellar populations of the other globular clusters are more uniform and older, as suggested by the theoretical models.
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These elements are thus in favor of the hypothesis of the remains of a dwarf galaxy whose periphery would have been dispersed and absorbed by the Milky Way. Some stars, like the Star of Kapteyn , which is only 12.8 light years away from us, would have even been ejected from the dwarf galaxy and then absorbed by the Milky Way.
The nucleus of the dwarf galaxy eventually ended up in orbit in the halo of the Milky Way and would have become Omega Centauri. In support of this hypothesis, we can also cite the high orbital speed of its stars with a maximum of 7.9 km / s, its flattened shape, and the presence in its center of an intermediate black hole with a mass evaluated at a maximum of 12,000 solar masses.
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Photo: Team Magellan with AP155mm f / 7.6 refractor and Moravian G4-16000 camera
Caldwell 81
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C81, or NGC 6352, is a globular cluster located about 18,300 light years from the Sun in the constellation Altar and about 12.7 billion years old. Its apparent diameter is approximately 7 arc minutes.
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Photo: Franz Hofmann and Wolfgang Paech with CDK12.5 telescope and Canon 700d
Caldwell 82
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C82, or NGC 6193, is a open cluster located approximately 3,765 light years from the Earth in the Altar constellation and about 3 million years old.
This open cluster is associated with the famous nebula in emission of the Dragons of the Altar NGC6188 (also called nebula of the hands of God) of which it ionizes the gases composing it.
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Pictures :
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- opposite the NGC6188 nebula by Jonathan Durand with Nikon 180mm f / 2.8 lens and QHY163m camera
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- below a close-up view of the Caldwell 82 cluster in the center of the nebula (upper left part of the image) by Janco with SW100 spirit and ASi1600mm scope
Caldwell 83
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C83, or NGC 4945, is a large barred spiral galaxy seen from the edge and located in the constellation Centauri about 13.6 million light years from the Milky Way. It is classified among the active galaxies of the Seyfert type and is also one of the members of the Centaurus A group which has at least 8 galaxies.
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Photo: Xing Keyu with Newton 500mm f / 3.6 and FLI16803 camera
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Caldwell 84
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C84, or NGC 5286, is a globular cluster located at approximately 38,000 light years of the Earth in the constellation of Centaur and about 12.54 billion years old.
NGC 5286 is part of Gaia-Enceladus , an ancient dwarf galaxy accreted by the Milky Way 8 to 11 billion years ago, which is also nicknamed the Gaia sausage and which is made up of at least 8 globular clusters.
Depending on the movement of the stars in the heart of this cluster, it could be that it contains a black hole of intermediate mass which could reach 6,000 times the mass of the Sun ,
Photo: Caldwell 84 and the star M Centauri by Rolf Wahl Olsen with Newton 10 "f / 5 and camera QSI683wsg
Caldwell 85
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C85, or IC 2391 the Omicron Velorum cluster is a open cluster located about 496 light years into the constellation from Sails .
It is a well distributed open cluster, similar to Pleiades M45 , and spanning nearly 50 minutes of arc .
It has about thirty main stars and a total of 325 members and is visible to the naked eye with its magnitude of 2.5.
IC 2391 appears to be the same age as the open cluster IC 2602 (the Southern Pleiades) about 50 million years old.
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Photo: Pablo Vera Tiznado with Newton 200/800 and camera QHY168C
Caldwell 86
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C86, or NGC 6397, is a globular cluster located at approximately 7,800 light years of the Earth in the constellation of the Altar . With M4 , it is one of the two globular clusters closest to Earth. Visible to the naked eye under very good viewing conditions, it contains approximately 400,000 star s.
NGC 6397 has been used in several recent astronomical researches, notably in 2004 to estimate the age of the Milky Way (13.6 billion years), and in 2005 to establish the minimum mass that a star must have for it to be able to "Light up" (start a process of nuclear fusion ): the researchers thus obtained a mass of 0.083 solar mass.
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Photo: Julian Shaw with APM 152mm scope and Atik 460EX camera
Caldwell 87
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C87, or NGC 1261, is a globular cluster located 53.2 million light years away in the Clock constellation . Its age is estimated at 10.24 billion years.
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Photo: Daniel Verschatse with RC14.5 "f / 7 and SBIG STL11000 camera
Caldwell 88
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C88, or NGC5823, is an open cluster located approximately 3888 light years away in the constellation Compass.
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Photo: Sergio Eguivar with Newton 200/1000 and QSI 583WS camera
Caldwell 89
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C89, or NGC 6067, is a open cluster in the constellation of the Ruler . It is approximately 102 million years old and has an angular diameter of 12 arc minutes.
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Photo: Dieter Willasch with T500 f / 3 and SBIG STL 11000M camera
Caldwell 90
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C90, or NGC 2867, is a planetary nebula located in the constellation Carina about 6,000 light years from Earth. Its apparent size is only 20 arc seconds.
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Pictures :
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- opposite drawing of Bertrand Laville with Dobsonian 500mm and 3.5mm eyepiece
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- below Wes Smith with Dobson 500mm f / 5 and Olympus E-PEN2 camera
Caldwell 91
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C91, NGC 3532, is an open cluster located approximately 1590 light years from the Sun in the constellation Carina and 310 million years old. Its apparent size is 50 arcminutes, which given its distance gives a maximum actual size of around 13 light years.
Photo :
- opposite Toshiya Arai with Epsilon 130 telescope and QH600 camera
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- on this large field of Jean-Baptiste Auroux we can locate Caldwell 91 near Caldwell 92 the Carina nebula
Caldwell 92
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C92, or NGC 3372 the Carina Nebula, is a emission nebula and an reflection nebula located about 8,500 light years in the constellation of the Carène .
This nebula is one of the largest HII regions known to our galaxy with a wingspan approaching 300 light years which gives it a apparent dimension of 120 minutes of arc, that is to say 2 degrees which represents an area in the sky of 4x4 Full Moons.
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Pictures :
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- below on the left Caldwell 92 in wide field realized by Chan Yat Ping Carl with Epsilon 160 telescope and SBIG STL-11002M camera
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-below on the right a close-up view by Uri Abraham with Stellarvue SVA 130 telescope and QSI 683wsg camera
Many remarkable objects are contained in the Hull such as:
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- the great stellar association OB: Carina OB1 (group of stars whose same own movement betrays a common origin but unlike a stellar cluster within which the stars are in gravitational interaction, the stars of an association are no longer subject to this force. OB associations such as Carina OB1 are groups of supergiant blue, very warm, young and massive).
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- Carina OB1 encompasses the open clusters Trumpler 14 (one of the youngest known, only 6.8 million years old) and Trumpler 16 (in which is the brightest star known in the Milky Way WR 25, type Wolf Rayet as the name suggests), as well as the famous Eta Carinae (a hypergiant star extremely bright with mass estimates ranging from 100 to 150 times that of the Sun and whose brightness is about four million times greater than that of the Sun. Its effects on the nebula can be observed directly, including dark blood cells and some other less visible objects have tails pointing directly in the direction of this massive star) .
Trumpler 15 clusters, Collinder 228, Collinder 232, NGC 3293 and the cluster of the nebula NGC 3324 are also considered members of the Carina OB1 association.
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- the Homunculus nebula which surrounds the star Eta Carinae (a bipolar cloud ejected from the star during a huge explosion in 1841), the keyhole nebula (the dark cloud of cold molecules and dust in the center of C92, silhouetted against the much brighter background nebula), and the Mystic Mountain (nickname given to a pillar of dust and gas that the hubble space telescope photographed to celebrate his 20th birthday).
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Pictures :
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- on the left, a close-up on the North West part of Caldwell 92 with the emission nebula Gabriela Mistral IC 2599 in the upper part (associated with the open cluster NGC3324 visible on the wide field image presented above), produced by EmuHead with newton 200/800 and ASI 1600mm camera
- right close-up on the south central part of Caldwell 92 by Ignacio Diaz Bobillo with AP167FLZ telescope and Alta U8300 camera
Caldwell 93
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C93, or NGC 6752 nicknamed Starfish or Windmill, is a globular cluster of the constellation of Peacock. Located approximately 17,000 light years from galactic center , it is also one of the globular clusters closest to the Earth. Its age is estimated to be around 11.78 billion years old.
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Photo: Tom Peter with TOA150 refractor and FLI16200 camera
Caldwell 94
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C94, or NGC 4755 also called the cluster of Kappa Crucis and nicknamed the Jewelry Box, is a young open cluster located in the constellation from the Southern Cross about 6440 light years from the solar system.
Its age is estimated at 16.4 million years. and its apparent size of 10 arc minutes gives a maximum real size of about 19 light-years given its distance.
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Photo: James Langston with Newton 200/800 and QSI183mm camera
Caldwell 95
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NGC 6025 is a open cluster located at approximately 2,700 light years in the constellation of Southern triangle .
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Photo: Steve Crouch with RC360mm and SBIG STXL 16200 camera
Caldwell 96
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C96, or NGC 2516 is a open cluster known as the Sprinter's Amas, located about 1330 light years from the Sun in the constellation of the Carène .
Its age is 113 million years. and its apparent size of 22 arc minute gives , given its distance, a maximum actual size of about 8.5 light years.
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Photos: Bernard Miller with CDK 17 "telescope and SBIG STXL-11002 camera
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Caldwell 97
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C97, or NGC 3766, is a young open cluster located approximately 5,690 light years into the constellation of the Centaur.
Its age is 14 million years. and its apparent size of 15 arc minute gives , given its distance, a maximum actual size of about 25 light years.
Caldwell 97 is located close to Caldwell
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Pictures : Jonah Scott with Newton 200/1000 and Sony A5100
Caldwell 98
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C98, or NGC 4609, is a young open cluster located about 4020 light years in the constellation of the Southern Cross within the great dark coal sack nebula (C99). Its age is 78 million years and its apparent size is 6 minutes of arc, i.e. an actual size of 7 light years.
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Photo :
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- opposite Ray Caro with 107/700 refractor and Canon 80d
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- below Jeff Lepp ( Jeff2011) with Nikon 200mm f / 2 and FLI16200 camera. Caldwell 98 can be seen slightly to the right of the center of the image.
Caldwell 99
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C99, the Sack of Coal, is a dark nebula located about 600 light years of the Earth , in the constellation of the Southern Cross . Spanning 7 x 5 degrees, it is the largest dark nebula in the Milky Way.
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Pictures :
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- opposite a C99 card by Bernard Hubl with 200mm f / 2.8 and Canon 6D
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- below a mosaic of 6 images made by Gabriel Rodrigues Santos with 135mm f / 2 lens and Canon 1200D + Canon Rebel T5. Among others, and from left to right: C99 the coal sack, the southern cross, C100 the running chicken nebula, C92 the Carina nebula and in the lower right corner C102 (southern pleiades).
Caldwell 100
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C100, or IC 2944, is a open cluster associated with a emission nebula located about 5,900 light years away in the constellation Centaur .
This object is also known as the Lambda Centauri Nebula or the Running Chicken Nebula.
Note the presence of several Bok globules (dark clusters of dust and gas from the interstellar medium in which the birth of stars) in this nebula which is most likely a region of star formation .
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Pictures :
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opposite by Maicon Germiniani with 115/800 refractor and ASI1600mm (mosaic of 4 images)
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- below a close-up view of the center and Bok globules by Brian Peterson with 17 "CDK and SBIG STXL 11002 camera
Caldwell 101
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C101, or NGC 6744, is a intermediate spiral galaxy located about 25 million light years of the Earth , in the constellation of Peacock . the diameter of his disk is about 150,000 light years away.
It is considered to be one of the most Milky Way-like spiral galaxies in our immediate vicinity.
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Photo: Johnny Wang with Newton 500mm f / 3.8 and FLI 16803 camera
Note the presence of the small satellite galaxy in the upper left part of C101 as well as the multiple distant galaxies populating the sky background of this region of the Peacock.
Caldwell 102
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C102, or IC 2602 (also known as Amas Theta carinae Where Pleiades South), is a open cluster located about 479 light years from Earth in the constellation of the Hull .
Like the Pleiades of the constellation Taurus M45 , the Southern Pleiades occupy a significant part of the sky, around 50 arc minutes. They are nevertheless less brilliant with a apparent magnitude overall of 1.9.
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Photos: a close-up view of Tim Hutchison with TOA 150 scope and camera FLI16200
Caldwell 103
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C103, or NGC 2070 the Tarantula Nebula, is a HII region located in the Large Magellanic Cloud, our neighbor galaxy, 160,000 light years from Earth .
It is the largest known nebula and has a higher star birth rate there than in any region of our Galaxy.
At its center, the open cluster responsible for UV radiation that ionizes the surrounding gas and makes the nebula visible is called R136a.
- opposite the great Magellanic Cloud by Stephan Westphal with 200mm f / 2.8 and Canon 5D
- below the Tarantula by Andy Campbell with TOA 130 refractor and QSI6162 camera
Caldwell 104
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C104, or NGC 362, is a globular cluster located about 27,000 light years in the constellation of Toucan and 10.37 billion years old.
Eccentricity from orbit of NGC 362 is quite high and its period of revolution around the center of the Milky Way is 3260 years old.
It is also located right next to the small cloud of Magellan, our neighbor galaxy, although it is not part of it, however, its alignment with this satellite galaxy of ours being fortuitous.
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Photo: The Small Magellanic Cloud by Stanislav Volskiy with FSQ106 telescope and SBIG STL 11000 camera. Caldwell 104 is the globular cluster located to the left of the galaxy while the large globular cluster at the top is Caldwell 106 (47 of the Toucan)
Caldwell 105
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C105, or NGC 4833, is a globular cluster located in the constellation of the Fly about 21,500 light years of the earth. Its age is estimated at 12.5 billion years.
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Photo: Claudio Tenreiro with Vixen ED80 refractor and ASI294MC camera
Caldwell 106
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C106, or NGC 104 (47 of Toucan), is a globular cluster located about 15,300 light years in the constellation Toucan and 13.06 billion years old. Its diameter of about 140 light years in diameter gives it an apparent size of 30 arc minutes, the size of the Moon.
In 2017 a black hole of intermediate mass was detected within Caldwell 106.
Photo: Yuichi Kawamato with Newton 500mm f / 3.6 and FLI16803 camera
Caldwell 107
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C107, or NGC 6101, is a globular cluster located approximately 50,000 light years away in the constellation Bird of Paradise. It is the southernmost globular cluster in the sky and its apparent size is 10.7 arc minutes.
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Photo: Jose Joaquin Perez with RC 16 "f / 8.4 telescope and Moravian G3-16200 camera
Caldwell 108
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C108, or NGC 4372, is a globular cluster located approximately 18,900 light years in the constellation of the Fly and 12.54 billion years old.
This small globular cluster is located west of the southern end of the remarkable dark nebula of Little Bidule (Dark Doodad Nebula).
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Photo: RossG with Nikon 300mm f / 4 and ASI 1600MC camera
Caldwell 109
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C109, or NGC 3195, is a planetary nebula located approximately 5,500 light years away in the constellation of the Chameleon. Its apparent dimension is 45x37 arc seconds.
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Photo: Rolando Ligustri with DK 450/2900 telescope and camera PL16603
