Ring Nebula M57
Ring Nebula, 57th in the Messier catalog, is a planetary nebula about 2,000 light-years away. It is the glowing remains of a sun-like star. NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration

As Earth approaches the debris field left behind by Halley’s Comet from its last visit to the inner solar system in 1986 — a transit that produces the annual Orionid meteor shower, which will peak in the early hours of Oct. 21 this year — NASA has released a new version of the Messier catalog. The newly released images of the non-comet Messier objects were all captured by the Hubble Space Telescope.

French astronomer Charles Messier first put together a catalog of non-comet celestial objects, called "Catalogue des Nébuleuses et des Amas d’Étoiles" ("Catalogue of Nebulae and Star Clusters"), in 1774 to help comet seekers by telling them what they should not waste their time on. It included, at the time of his death, 103 objects, but the catalog was revised in the 20th century to include a total of 110 objects, all of which can be observed from Earth’s northern hemisphere.

The Hubble catalog gallery currently shows 90 photographic images of 63 of these so-called Messier objects. Most of these are images taken from the archives of over 1.3 million photographs taken by the space telescope. Eight photographs, however, have never been released by NASA before and are newly processed. Among the older images, some "represent the first Hubble views of the objects, while others include newer, higher resolution images taken with Hubble’s latest cameras," according to a NASA statement Thursday.

The first image in the Messier catalog, called M1, was that of the Crab Nebula, which Messier mistook for the Halley’s Comet — his inspiration for creating his catalog. The Hubble image of the nebula, which is 6,500 light-years from Earth, is a combination of 24 separate exposures taken over three months.

Crab Nebula
The crab nebula was created as a result of a supernova explosion. The orange filaments are the tattered remains of the star and consist mostly of hydrogen. The blue in the filaments in the outer part of the nebula represents neutral oxygen. Green is singly ionized sulfur, and red indicates doubly ionized oxygen. NASA, ESA, J. Hester and A. Loll (Arizona State University)

The other objects in the Messier catalog have been named M2, M3, M4 and so on. Below are some of the spectacular Hubble images of some of these objects.

M4 Globular Cluster
M4 is a globular cluster 5,500 light-years away from Earth, the closest object of its kind. It is home to over 100,000 stars and is more than twice as old as the solar system. ESA/Hubble & NASA
M8 Herschel 36
M8 is a nebula, and the bright star near the center of this is called Herschel 36. NASA, ESA, J. Trauger (Jet Propulsion Laboratory)
Eagle Nebula - Pillars of Creation
M16 is better known as the Eagle Nebula, and this image shows the equally well-known Pillars of Creation — towers of cosmic gas and dust at its heart. The nebula is located 7,000 light-years away. NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Trifid Nebula M20
M20 is a star-forming nebula located 9,000 light-years away from Earth in the constellation Sagittarius. Also known as the Trifid Nebula, it was named after the three wing-like bands of thick dust in its center. NASA, ESA, and the Hubble Heritage Team (AURA/STScI) Acknowledgment: F. Yusef-Zadeh (Northwestern Univ.)
Orion Nebula M42
Popularly known as the Orion Nebula, M42 was believed to be the cosmic fire of creation by the Maya of Mesoamerica. The nebula is only 1,500 light-years away, making it the closest large star-forming region to Earth. This image was created using 520 individual exposures by Hubble in different wavelengths. NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team
Sunflower Galaxy M63
M63, or Sunflower Galaxy, is a flocculent spiral, which is to say, it appears to have many discontinuous arms instead of the well-defined arms as seen in our home galaxy, the Milky Way. M63 is about 27 million light-years away. ESA/Hubble & NASA
Spindle Galaxy M102
M102 is a spindle galaxy, which are likely formed when two spiral galaxies collide at right angles to each other and then merge. This is an edge-on view of the galaxy, located 44 million light-years from Earth. NASA, ESA, and the Hubble Heritage Team (STScI/AURA) Acknowledgment: W. Keel (University of Alabama, Tuscaloosa)
Sombrero Galaxy M104
Better known as the Sombrero galaxy after its apparent shape, M104 is seen almost edge-on from Earth. The galaxy, located 28 million light-years away, likely has a black hole at its center whose mass is one billion times the sun's. NASA and the Hubble Heritage Team (STScI/AURA)

Even though only 63 Messier objects are in the Hubble catalog currently, a total of 93 Messier objects have been imaged by the telescope as of September 2017. Not all images obtained by the space telescope are photographic, however. Some of these images are spectra — a breakup of the object’s light into component wavelengths that help identify properties like the object’s chemical composition, temperature and the velocity it is traveling at. These spectral images were not included in the newly released catalog.

There are limitations of Hubble’s capacity (it has a relatively small field of view, even though it’s magnification is very efficient) and on the observation time, imposed by demands from scientists and astronomers around the world for various research purposes. This is partially why the Hubble catalog of Messier objects does not include all the 110 objects in the original.

The colors seen in the Hubble images released by NASA are not how the objects will appear to the human eye. The telescope can see in wavelengths of light beyond the human capacity for vision, and features visible only in such wavelengths are given false colors to make them visible to humans.

NASA has made all the Hubble photographs (as well as a portrait of Messier) of Messier objects available on this Flickr page.

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