Hubble's Caldwell Catalog

The Caldwell Catalog goes beyond the work of Charles Messier, offering backyard astronomers more cosmic wonders to explore.

Quick Fact

Browse Hubble's Caldwell catalog objects in the night sky. To explore the Caldwell Skymap, scroll, double click, or pinch/swipe to zoom. Roll over an icon to see the object, click to zero in, and click again for a detailed view. Drag the map to navigate.
Background Image: ESA/Gaia/DPAC; CC BY-SA 3.0 IGO. Acknowledgement: A. Moitinho

Overview

During the 18th century, French astronomer Charles Messier compiled a list of over 100 cosmic objects that might fool fellow comet hunters into thinking they had discovered new comets. These smudgy spots on the sky have since been revealed as distant galaxies, star clusters, and nebulae, and the Messier catalog became a guide for locating visually stunning cosmic objects.

Caldwell 33 and 34
This image of Caldwell 33 and 34, known collectively as the Veil Nebula, demonstrates Hubble's high resolution but small field of view. The large image was taken by a ground-based telescope, while the three insets are Hubble close-up views.
NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and the Digitized Sky Survey 2. Acknowledgment: J. Hester (Arizona State University) and Davide De Martin (ESA/Hubble)

In the 1980s, an Englishman named Sir Patrick Moore produced an additional list to highlight more cosmic wonders visible to amateur astronomers. Unlike the Messier catalog, which only features objects that were visible from Charles Messier’s viewing location in Europe, Moore’s Caldwell catalog includes celestial bodies that are found in both the northern and southern skies. The catalog consists of 46 star clusters, 35 galaxies, and 28 nebulae, or 109 objects in total. Moore intentionally avoided including any of the Messier objects in his catalog, hoping to expand his fellow amateur astronomers’ cosmic horizons. From nearby clouds of gas and dust that are left over from dying stars to remote galaxies that formed billions of years ago, the Caldwell catalog is brimming with surprising celestial treats.

While the Hubble Space Telescope has not taken images of every object in the Caldwell catalog, it has observed 98 of them as of August 2020. Processed images for 87 Caldwell objects are included here. More images may be added to Hubble’s catalog of Caldwell objects in the future.

Some of Hubble’s images are close-ups of a particularly interesting region of an object rather than capturing the whole thing. That’s because Hubble provides high-resolution views but of relatively small regions of the sky. Sometimes the entire astronomical object doesn’t fit in Hubble’s view, and the scientists taking the observations don’t always need to view the full object for their studies.

Other Hubble images of the Caldwell objects have an unusual staircase-like shape where an edge of the picture appears cut off or missing. These images were taken using the Wide Field and Planetary Camera 2 (WFPC2), which was in operation between 1994 and 2009. WFPC2 was made up of four light detectors with overlapping fields of view, one of which gave a higher magnification than the other three. When the four images were combined together into one picture, the high-magnification image needed to be reduced in size in order for the image to align properly. This produced an image with a layout that looked like steps.

Today, Hubble has two primary cameras to capture images of the cosmos. Called the Advanced Camera for Surveys and the Wide Field Camera 3, they work together to provide superb wide-field imaging over a broad range of wavelengths. The telescope’s visible-light observations allow us to view cosmic objects in the wavelengths of light we see with our own eyes, but in a much greater level of detail. Infrared observations extend our vision, detecting lower-energy light than our eyes can see and peering through shrouds of dust to image some of the faintest and farthest objects yet discovered. Hubble’s ultraviolet vision extends our view in the opposite direction, opening a window on the evolving universe and allowing us to glimpse some of the more violent events in the cosmos.

While Hubble provides images in exquisite detail, backyard astronomers can observe Caldwell objects with modest ground-based telescopes, though some are more challenging targets than others. The catalog features many deep-sky objects that are bright enough to see with binoculars and a few that are visible to the naked eye. Regardless of the viewing instrument, the Caldwell objects are rich in history, brimming with science, and fun to observe.

The following pages contain some of Hubble’s best images of the Caldwell objects taken thus far. This collection has been assembled for amateur astronomers to compare what they see to what Hubble sees, allowing them to see finer details in each of the objects.

Caldwell Objects
While the Messier catalog is limited to celestial objects that are visible from the Northern Hemisphere, the Caldwell catalog spans the entire sky. This all-sky map shows the locations of all the Caldwell objects. - View SVG file
Jim Cornmell (CC BY-SA 3.0)

History

Sir Patrick Moore

World-renowned amateur astronomer, Sir Patrick Moore, developed the Caldwell catalog to inspire backyard astronomers to view night-sky wonders beyond those in the Messier Catalog.

Like many avid stargazers, an Englishman named Sir Patrick Moore developed an interest in astronomy at a very young age, which blossomed into a lifelong obsession. Educated at home because of a heart condition, he discovered the world of astronomy at six years old when he read a late 19th century tome on the solar system.

Read More
headshot of an older man with gray hair and a monocle on his right eye standing in front of a brick wall
Sir Patrick Moore (1923–2012) was an English amateur astronomer, writer, and television host. He developed the Caldwell catalog to complement the Messier catalog, with a goal of enticing fellow amateur astronomers to experience more of the wonders of the night sky.
South Downs Planetarium (CC BY-SA 3.0)

Hubble’s Caldwell Catalog

Use Hubble's images to help guide your exploration of the Caldwell catalog.

Stars with four diffraction spikes dot the scene against a black backdrop.

Caldwell 1

Also known as NGC 188, this group of stars formed from a large cloud of gas making the stars roughly…

Red cloud of dust with a bright white star in the center of it. Lots of reddish and orangish stars in the background.

Caldwell 2

This shell of gas is expanding outward, away from the dying star within.

Large grouping of bright white, blue and red stars. Lightly colored blue dust surrounds the stars.

Caldwell 3

This barred spiral galaxy was first spotted by British astronomer William Herschel in April 1793 in the constellation Draco.

Large cloud of dark purple dust and gas with a few orange stars peppered throughout.

Caldwell 4

Also called the Iris Nebula, or NGC 7023, Caldwell 4 is of particular interest to astronomers.

On the left side of the image is a spiral galaxy, on the right the inset shows a zoom in with dark red stars and dust and gas.

Caldwell 5

Though bright, this spiral galaxy is very difficult to find in the crowded sky area near the Milky Way's disk…

Large clouds of white dust and gas surrounding a bright white star in the center.

Caldwell 6

Caldwell 6 is also known as NGC 6543, but is commonly called the Cat’s Eye Nebula.

C7-1

Caldwell 7

Supernova hunters may be familiar with Caldwell 7 as the galaxy hosted a supernova in 2004.

Large blue cloud of dust and gas forms a border around a grouping of yellow stars.

Caldwell 9

Also called the Cave Nebula, Caldwell 9 is an area where new stars are forming.

A bubble of blueish gas expands in the lower center of the image. Gas and dust in yellow, green, and brown hues fills the rest of the image.

Caldwell 11

Better known as the Bubble Nebula, Caldwell 11 is a colorful region of gas and dust that stretches 6 light-years…

Large spiral galaxy with bright white center, surrounded by countless blue, white, and purple stars. Light blue dust and gas surrounds it.

Caldwell 12

This majestic spiral has had ten observed supernovae in its spiral arms since 1917.

Bright blue stars pepper the dark black sky

Caldwell 14

These two bright star clusters appear side by side in the northern sky, about halfway between the constellations Perseus and…

Bright green dust and gas surrounds an inner shell of tightly wound dust and gas, in the center of it all is a bright purple star.

Caldwell 15

A blinking remnant star, called a white dwarf, sits at the heart of this colorful nebula.

Countless points of light, each of them a star, brought together in this image of a giant galaxy.

Caldwell 17

Also known as NGC 147, Caldwell 17 is a dwarf galaxy in our local group of galaxies.

Bright grouping of countless stars, getting brighter and brighter as you move to the center of the egg shaped galaxy.

Caldwell 18

Caldwell 18 is a nearby galaxy in the local group with an active galactic nucleus.

Large bright star at the top left of the image, surrounded by dark dust and gas. Stars pepper the image in the bottom right.

Caldwell 20

Nicknamed the North American Nebula because its shape resembles the continent, Caldwell 20 was discovered by William Herschel in 1786.

Large grouping of stars and bluish dust and gas. Near the center the stars create a bright white light. Galaxy is a amorphous blob.

Caldwell 21

Discovered in 1788 by astronomer William Herschel, Caldwell 21 is dwarf irregular galaxy bursting with forming stars.

Light blue dust and gas forms an egg shaped shell surrounding a bright white star in the center. There is an outer shell as well, also light blue, with some pink on the edges.

Caldwell 22

Also known as NGC 7662, Caldwell 22 is nicknamed the Snowball Nebula or Blue Snowball Nebula.

Thin line of stars and dust and gas, the side view of a galaxy. This galaxy is diagonal across the image, with the blackness of space behind it.

Caldwell 23

Spanning some 100 000 light-years, Caldwell 23 is seen exactly edge-on, revealing its thick plane of dust and interstellar gas.

Large glob of stars surrounded by dark rusty red gas and dust. Huge bright stars surround the bright galaxy in the center.

Caldwell 24

Caldwell 24 is one of the closest giant elliptical galaxies to Earth and was discovered by William Herschel in 1786.

Huge grouping of countless stars, in colors red, blue, white, yellow. The closer to the center of the image, the brighter, and whiter it gets.

Caldwell 25

Dubbed "the Intergalactic Wanderer,” Caldwell 25 is different from the Milky Way's other globular clusters.

Long thin galaxy view, nearly from the side but tilted a bit toward the viewer. Lots of white stars throughout, but they get thicker and brighter near the center.

Caldwell 26

Also called NGC 4244 and the Silver Needle Galaxy, Caldwell 23 is part of the same galactic super cluster as…

colorful streams of yellow, blue, and green gas and dust extend from the lower left to the center right. At the bottom right is a black and white image from a ground based telescope.

Caldwell 27

Also called the Crescent Nebula or NGC 6888, Caldwell 27 holds a massive, incredibly hot star at its heart.

45 degree view of a spiral galaxy. Dark blue dust and gas covers up most of its millions of stars, but the core, center of the image, is bright white.

Caldwell 29

You can spot this spiral galaxy's bright core in most backyard telescopes.

45 degree angle view of a spiral galaxy. Lots of dark purple and blue dust and gas orbits the bright yellow center.

Caldwell 30

Head to a dark sky to see this galaxy's sweeping spiral arms in larger telescopes.

Long thin side view of a galaxy. On the left side, a larger part of it, closer to the central core. Lots of gas and dust surrounding countless stars. The stars softly stretch out to the right of the image.

Caldwell 32

One of the brighter Caldwell galaxies, Caldwell 32 is similar to our own Milky Way.

Wisps of red, yellow, blue and purple dust and gas dance all over the image. The blackness of space frames the image behind it.

Caldwell 33

Caldwell 33 is the eastern part of the Veil Nebula.

A colorful rainbow chain of gas and dust stretches across the image from the lower left corner to the upper right.

Caldwell 34

Caldwell 34 is the western part of the Veil Nebula.

Large, egg shaped, white galaxy in the center, surrounded by stars and dust, other galaxies behind the center one peppered throughout.

Caldwell 35

Caldwell 35 is so far away that it takes light from the galaxy 300 million years to reach Earth traveling…

Large spiral galaxy, countless stars surround the bright center core of the galaxy in the middle of the image. The arms of the galaxy are dusty red clouds of gas enmeshed by blue stars throughout.

Caldwell 36

Northern Hemisphere observers can spy this beauty in the spring, while Southern Hemisphere observers should look for it in the…

Thin side view of a galaxy, surrounded by dark plumes of gas and dust, blocking most of the stars on the outer edges. But in the center, a bright white light which is the core of the galaxy.

Caldwell 38

Also called "The Needle" galaxy, or NGC 4565, Caldwell 38 was discovered by astronomer William Herschel in 1785.

At the center of the image is the dying star. It's surrounded by a white-and-orange wispy "cloud" of gas. Farther away, more gas and dust creates an orange-and-yellow circular "ring" around the center.

Caldwell 39

A dying star at Caldwell 39's heart began shedding its outer layers 10,000 years ago.

A spiral galaxy has a glowing white center and wispy arms of gas that are reddish-brown at the thickest parts and whitish-pink for the smaller arms. The galaxy is surrounded by a bluish-white glow.

Caldwell 40

Hubble’s Wide Field Camera 3 helped astronomers better understand the cores of galaxies like Caldwell 40.

This is a globular cluster, a sphere of tens of thousands of stars. Most of them are a whitish color, and more concentrated in the center of the sphere. As you move farther from the center, there are fewer stars.

Caldwell 42

Globular clusters like Caldwell 42 are relics of our galaxy's youth.

The pinkish-brown disk of a spiral galaxy, viewed from head-on and looking like a straight line, stretches across the picture. The center of the galaxy is glowing white and looks spherical, and a white glow radiates outward from it, encompassing the whole galactic disk.

Caldwell 43

Known as the “Little Sombrero,” Caldwell 43 was documented by British astronomer William Herschel in 1784.

A "barred spiral" galaxy is shaped like a backward S, with its arms of gas and dust made up of whites, pinks, red-browns, and pale blues. The center of the galaxy (the middle of the S) is a glowing white sphere.

Caldwell 44

Shaped like a backward "S," Caldwell 44 is visible in autumn from the Northern Hemisphere and in spring from the…

This spiral galaxy is shaped like a hurricane, with a glowing white spherical center. The arms of gas and dust closest to the center are orange, red, brown, and pale yellow in color. Farther away from the center, the arms are layers of brown and blue.

Caldwell 45

Hubble captured reddish-pink clouds of star-forming regions in this spiral galaxy.

This nebula is shaped like a fan, with the star glowing white in the bottom left. Trailing upwards away from it, like a veil, the gas and dust is bluish-white closest to the star, then turns to a light blue farther away, and then to a deep turquoise at the ends, which are on the top right.

Caldwell 46

This fan-shaped cloud of gas and dust shines by the light of a bright star at the bottom end of…

This is a globular cluster, a sphere of tens of thousands of stars. Most of them are a whitish color, and more concentrated in the center of the sphere. As you move farther from the center, there are fewer stars.

Caldwell 47

Hubble helped provide clues to the origin of young, hot, blue stars in Caldwell 47.

A galaxy with a large, yellow core shines against black space, surrounded by feathery, short spiral arms laced with dark brown dust and blue regions of star formation.

Caldwell 48

Majestic Caldwell 48 offers a color contrast with its bright-yellow heart and sparkling young, hot, blue stars in its dusty…

Tens of thousands of tiny dots of varying colors, each one its own star in C51, look like dust against the black backdrop of space. A few larger objects like reddish disks of spiral galaxies can be seen.

Caldwell 51

This irregular dwarf galaxy is in the constellation Cetus.

An elliptical galaxy emits a bright white glow that surrounds it like a halo.

Caldwell 52

Slightly larger than the Andromeda galaxy, this massive elliptical distorts its neighbors with its gravitational influence.

Black background dotted with stars. Image center holds an elliptical haze of white light. Along the horizontal axis of the ellipse is a band of brighter light. The center of the ellipse holds a small, bright sphere of light.

Caldwell 53

Astronomers estimate that the black hole at Caldwell 53's heart has a mass roughly one billion times the mass of…

A bright pink central star is surrounded by a football-shaped rim of dense blue and red gas. The cavity and its rim are trapped inside smoothly-distributed greenish material in the shape of a barrel and comprised of the star's former outer layers. At larger distances, and lying along the long axis of the nebula, a pair of red "ansae", or "handles" appears. Each ansa is joined to the tips of the cavity by a long greenish jet of material.

Caldwell 55

Also known as the Saturn Nebula and NGC 7009, Caldwell 55 holds a dying star at its heart.

Near the center of the image is a bright orange star, and in the upper left, are two reddish-pink stars near each other. The entire image is filled by a turquoise, cloud-like "bubble".

Caldwell 56

The best time to observe Caldwell 56 is during the Northern Hemisphere’s autumn and the Southern Hemisphere’s spring.

Tens of thousands of stars fill this image as tiny dots, more concentrated in the upper left corner. Stars taper off as you move down and to the right.

Caldwell 57

Also called NGC 6822, this galaxy was discovered in 1884 by American astronomer E. E. Barnard and is often called…

Several very bright stars are scattered throughout the field of view, with many fainter ones behind them. Most of the brightest stars are bluish-white, while the rest have a reddish-orange hue, and some slightly-less-bright stars are deep red.

Caldwell 58

Caldwell 58 is also called Caroline’s Cluster in honor of astronomer Caroline Herschel.

A blue star shining at the center of the nebula is surrounded by a thick white bubble, which turns pale orange at the outer edges. It has a small red "flare" outside this bubble at either pole, and a thick spherical layer of blue around the whole structure.

Caldwell 59

Also called NGC 3242 and the Ghost of Jupiter, Caldwell 59 was discovered by astronomer William Herschel in 1785.

Two galaxies merge, a larger one at the top of the image and a smaller one below it. Both galaxies glow with a yellowish center, have rings of pink and bluish-white stars around them, and are connected by a large cloud of dust, brown, red, and pink.

Caldwell 60/61

Better known as the Antennae galaxies, Caldwell 60 and 61 are a pair of interacting spiral galaxies.

The galaxy's nucleus is visible here as a bright, whitish patch, surrounded by a mixture of bluish-white stars and blackish clouds of gas and dust.

Caldwell 62

This dwarf spiral is also known as the Needle's Eye galaxy.

This zoomed-in image of the Helix nebula seems to make a rainbow outwards from the star. It's blue at the center, fading to white, then yellow, then orange, and finally red at the outer edges.

Caldwell 63

Better known as the Helix Nebula, Hubble's image of Caldwell 63 is one of its most iconic.

In this wide-field image, the center of the galaxy is on the left, surrounded by dark clouds of gas, which make several "rings" of spiral arms around the center that extend farther and farther out to the right, filled with white stars in between.

Caldwell 65

Also called the Sculptor galaxy, Caldwell 65 was discovered in 1783 by British astronomer Caroline Herschel while she was hunting…

Bright-white spherical cluster of stars in the upper left corner. Stars taper off down and out to the right of the cluster against a black background. Reddish-orange stars dot the scene.

Caldwell 66

Also known as NGC 5694, Caldwell 66 was discovered by William Herschel in 1784 and is one of the oldest,…

A white ring of stars surrounds the orangey center glow. Two reddish-brown arms of gas and dust emerge from opposite sides around the center. These arms become more bluish, with scattered trails of pink, at the ends.

Caldwell 67

This beautiful spiral galaxy is best viewed in early summer from the Southern Hemisphere or early winter from the Northern…

Two bright stars shine a distance away from each other, looking like eyes. An orangey haze emanates around and between them.

Caldwell 68

A young star whose brightness fluctuates over time illuminates this reflection nebula.

Two lobes of gas and dust expand outward from the center toward the lower left and upper right of the image. The center of each lobe is bright-white ringed by a rose-pink and then a rusty, orange-brown. The nebula is on a black background dotted with stars.

Caldwell 69

A dying Sun-like star is ejecting layers of gas to create Caldwell 69, giving it the more common names of…

The very center of the galaxy glows bright white. All around it, the white stars of its spiral arms resemble grains of sand. There are scattered dark tufts of dust and gas scattered throughout.

Caldwell 70

Also known as NGC 300, Caldwell 70 is a member of a nearby Sculptor group of galaxies.

Several very bright stars are scattered throughout the field of view, with many fainter ones behind them. Of the four brightest stars, two have a reddish-orange hue, one is reddish-white, and one is bluish-white.

Caldwell 71

Backyard observers can find this group of stars by using the bright stars Sirius and Canopus as guides.

The center of the galaxy glows in a pinkish-white, and is tilted diagonally, going up-right and down-left. Black clouds of dust are visible around the center, and in the lower left corner, thick blue "clumps" of stars.

Caldwell 72

This galaxy is similar to, but smaller than, the Large Magellanic Cloud.

This is a globular cluster, a sphere of tens of thousands of stars. Most of them are a whitish color, but there are many bright red, yellow, and blue stars mixed in. The stars are more concentrated in the center of the sphere. As you move farther from the center, there are fewer stars.

Caldwell 73

Caldwell 73 may be a remnant of two clusters that collided within a dwarf galaxy that once hosted them both.

A bright star shines at the center of a rainbow-colored "bubble" spreading outward from it. The inner oval around the star is a turquoise color, which has a yellow ring around it, which then turns to orange, and has red wisps at the outer edges.

Caldwell 74

Also known as the Southern Ring, this beautiful nebula is the result of a small dying star at its heart.

Several bright stars in colors of blue-white and red against the black background of space.

Caldwell 76

This bright star cluster was first cataloged by the Italian astronomer Giovanni Battista Hodierna.

C77 is a mixture of prominent dark dust lanes and bright yellow glowing areas sprinkled with red groupings of stars.

Caldwell 77

Better known as Centaurus A, Caldwell 77 is the closest active galaxy to Earth.

A bright, compact, spherical cluster of stars in colors of white, blue and red.

Caldwell 78

This beautiful globular cluster is best seen from equatorial latitudes.

A field of large bright yellow stars and smaller blue and white stars.

Caldwell 79

Caldwell 79, also called NGC 3201, was discovered by Scottish astronomer James Dunlop in 1826.

A compact spherical cluster of so many stars that their light blurs together.

Caldwell 80

Better known as Omega Centauri, Caldwell 80 is home to around 10 million stars.

A cluster of bright blue and yellow stars against the black background of space. A single bright red star is to the far right.

Caldwell 81

Located in the constellation Ara, the Altar, Caldwell 81 was discovered in 1826 by Scottish astronomer James Dunlop while he…

Several very bright whitish stars are clustered together, with a number of smaller and dimmer red stars around them.

Caldwell 82

This bright open cluster of stars is just visible to the unaided eye away from light polluted skies.

Dark lanes of dust and gas are scattered with red and white stars. The image has the step-shape format caused by the WFPC2 camera.

Caldwell 83

Caldwell 83 is interesting to astronomers because it is the source of the first water megamaser.

The nearly spherical globular star cluster Caldwell 84 is dense and thick with stars. Whiter stars appear near the center and blue and red stars farther out.

Caldwell 84

Scattered light from a nearby bright star can interfere with observing this beautiful cluster.

A cluster of bright blue, red and white stars against the black background of space.

Caldwell 86

Caldwell 86 is a true cosmic relic at a staggering 13.4 billion years old.

A spherical cluster of bright white, red, and blue stars.

Caldwell 87

This image combines observations from Hubble’s Wide Field Camera 3 in visible and ultraviolet light with infrared observations from its…

This black and white image is dominated by a single large, bright star with x-shaped beams of light emanating from it across the image. Other, smaller stars are visible around it.

Caldwell 89

This cluster is visible in binoculars, and a small telescope can resolve some of its stars.

A cloud of white-gray gas with a star at its center, with a scattering of small red stars around it.

Caldwell 90

A dying Sun-like star gave us Caldwell 90.

A tumultuous landscape of gas and dust, filled with bright glowing clouds, knots of darker gas, and stars.

Caldwell 92

Better known as the Carina Nebula, Caldwell 92 offers us a wealth of science and beautiful images.

A collection of many white stars against the black background of space. They are more concentrated in the center of the cluster.

Caldwell 93

Hubble’s observations of Caldwell 93 also uncovered an unexpected galaxy.

Several bright white stars with x-shaped spikes of light are located to the left of the image. A few more, inclucing some reddish stars, are at the edge of the image to the right. Smaller scattered stars are in the background against black space.

Caldwell 94

This open cluster is a relative youngster at about 16 million years old.

Scattered white and reddish stars on a black background, with the largest and brightest stars to the left and right of the image.

Caldwell 96

Caldwell 96 was first recorded by the French astronomer Nicolas-Louis de Lacaille in 1751 from the Cape of Good Hope…

A handful of bright stars amidst and around a blue misty blob of glowing gas.

Caldwell 99

Visible to the unaided eye as it obscures part of the Milky Way, dark Caldwell 99 is better known as…

A rusty-orange background is dotted with dark clouds. One large, dark cloud at upper right, two medium-sized dark clouds at the bottom; one left, the other right, of center. The upper left corner is blacked-out in a step pattern.

Caldwell 100

With dark clouds, an emission nebula, and embedded star clusters, Caldwell 100 offers a wealth of things to see.

A large spiral galaxy fills the frame. A bright core of stars, just left of center. Dust-filled spiral arms wrap around toward the top, right, and bottom of the image.

Caldwell 101

Caldwell 101's spiral shape is more than 200,000 light-years across, well beyond this Hubble view.

Tones of rusty-brown, blue, white, and a smattering of red fill the scene. Left of center holds bright-white tendrils of gas and a star cluster. Surrounding the cluster are tendrils and clumps of rusty-brown gas. Upper-left background glows faintly dark blue, while the lower half of the image holds a black background. Many stars dot the scene, their light shining within or through the nebula.

Caldwell 103

Better known as the Tarantula Nebula or 30 Doradus, Caldwell 103 the brightest star-forming region in our galaxy.

A spherical mass of stars fills the scene. Bright-white stars are concentrated at image center. They taper off as you move toward the image's edge. Yellow and blue-white stars dot the region beyond the core.

Caldwell 104

The stars of Caldwell 104 have a surprisingly high metal content, which means that it formed more recently than expected.

Black background littered with stars. Slightly denser number of stars at center that taper off toward the image's edge. A few bright stars with diffraction spikes and an orangish halo.

Caldwell 105

This colorful cluster was discovered by French astronomer Nicolas-Louis de Lacaille in 1751 during a journey to South Africa.

c106-1

Caldwell 106

Hubble observations of Caldwell 106 revealed a dynamic conveyor belt of star motion within the cluster.

A grouping of blue and reddish stars against the black background of space.

Caldwell 107

This loosely-packed cluster of stars was first observed in 1826 by Scottish astronomer James Dunlop.

Scattered blue and white stars against a black background. A black line runs horizontally through the image.

Caldwell 108

The colorful stars of Caldwell 108 offer clues to the cluster's internal dynamics and subsequent evolution.

A grayish oval nebula with a star at its center. Four red stars are located near the top of the nebula.

Caldwell 109

A dying star at Caldwell 109's heart shed its outer layers, creating a shell of gas around the star.