230227 - M100 "Blowdryer" galaxy
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click image to enlarge
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ASTRO:
type=Grand Design Spiral galaxy const=Coma Berenices mag=9.4 dist=55 M ly size=107 k ly IMAGE: location=EB Driveway BrtlCls=4 moon=53% WxHalf exposure=CMOS OSC 65x180s (3.3h), Gain100 EQUIPMENT: camera=ZWO ASI2600MC-Pro optics=ES102 w24mmEP afocal, F(eff.)=1238mm, f/12.1 (eff.) filter=Optolog L-Pro LPS mount=Celestron AVX guiding=Orion 60x240mm, ZWO ASI224MC SOFTWARE: acquisition=Stellarium, APT, PHD2 processing=PixInsight, RCAstro, PhotoshopCC, Lumenzia, APF-R, LrC |
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Majestic on a truly cosmic scale, Messier 100 (or M100 - the 100th object listed in the Messier catalog) is appropriately named the "Blowdryer Galaxy". Also known as NGC 4321, it is a stunning example of a grand-design spiral galaxy that is oriented almost perfectly face-on from our point of view here on Earth. Its prominent spiral arms consist of dusty structures that swirl around the galaxy’s nucleus and are marked by a flurry of star formation. M100’s characteristic arms also host several small black holes, including the youngest one ever observed in our cosmic neighborhood.
The Blowdryer is a large galaxy of over 100 billion stars, similar to our own Milky Way Galaxy. One of the brightest members of the Virgo Cluster of galaxies, it is appx 55 million light-years away toward the constellation of Berenice's Hair (Coma Berenices). At that distance, it is calculated to be appx 107,000 light-years in diameter, which is appx 60% the size of the Milky Way. This image of M100 shows in blue and red colors, winding dust lane arms which are hallmarks of this class of galaxy. Studies of variable stars within M100 have played an important role in determining the size and age of the Universe.
The galaxy was discovered in 1781 by the French astronomer Pierre Méchain, who was Charles Messier’s fellow comet hunter, and who discovered eight comets in his lifetime. Then 29 days later, it was seen and recorded by Charles Messier in his catalogue of "of non-comet-like objects". M100 was one of the first spiral galaxies to be discovered, and was listed as one of fourteen spiral nebulae by Irish astronomer, naturalist and engineer Lord William Parsons of Rosse in 1850. NGC 4323 and NGC 4328 are satellite galaxies of M100. They are plainly visible in this image above and to the upper right of larger galaxy, although they may be mistaken for stars. NGC 4323 is connected with M100 by a bridge of dark, dusty matter.
After the discovery of M100 by Méchain, Charles Messier observed and wrote about the galaxy, describing it as a nebula without a star. He pointed out that it was difficult to recognize because of its faintness. William Herschel was able to identify a bright cluster of stars within the "nebula" during his observations; and, his son John Herschel expanded his father's findings in 1833 when using a more advanced telescope, he reported seeing a round, bright galaxy. Then in 1844, English Royal Navy officer, hydrographer, astronomer and numismatist William Henry Smyth extended the studies of M100, detailing it as a pearly white nebula and pointing out diffuse spots.
M100 is considered a starburst galaxy with the strongest star formation activity concentrated within a ring in its center, and with two tightly wound spiral arms attached to a small nuclear bar. Scientists believe star formation has been taking place there for at least 500 million years. As is usual for spiral galaxies in the Virgo Cluster, the rest of M100's disk sees a deficiency of both star formation and neutral hydrogen when compared to isolated spiral galaxies of similar type and size in other parts of the universe.
M100 appears very dim in the night sky. Its apparent magnitude of 9.4 means that, while it can be seen in very dark skies through small telescopes; it appears only as a very faint patch of light. Larger telescopes (200mm and larger) are needed to resolve more details. Imagers on the other hand can capture it quite readily using modestly sized equipment.
M100 comes into view above the eastern horizon in the early mornings of November. It then progresses to evening visibility in March. It is best observed during May when high in the sky where observers and imagers may look through the thinnest part of Earth's atmosphere. It remains visible throughout the summer until it disappears below the western horizon in September, not to return again until the early mornings of late November.
The Blowdryer is a large galaxy of over 100 billion stars, similar to our own Milky Way Galaxy. One of the brightest members of the Virgo Cluster of galaxies, it is appx 55 million light-years away toward the constellation of Berenice's Hair (Coma Berenices). At that distance, it is calculated to be appx 107,000 light-years in diameter, which is appx 60% the size of the Milky Way. This image of M100 shows in blue and red colors, winding dust lane arms which are hallmarks of this class of galaxy. Studies of variable stars within M100 have played an important role in determining the size and age of the Universe.
The galaxy was discovered in 1781 by the French astronomer Pierre Méchain, who was Charles Messier’s fellow comet hunter, and who discovered eight comets in his lifetime. Then 29 days later, it was seen and recorded by Charles Messier in his catalogue of "of non-comet-like objects". M100 was one of the first spiral galaxies to be discovered, and was listed as one of fourteen spiral nebulae by Irish astronomer, naturalist and engineer Lord William Parsons of Rosse in 1850. NGC 4323 and NGC 4328 are satellite galaxies of M100. They are plainly visible in this image above and to the upper right of larger galaxy, although they may be mistaken for stars. NGC 4323 is connected with M100 by a bridge of dark, dusty matter.
After the discovery of M100 by Méchain, Charles Messier observed and wrote about the galaxy, describing it as a nebula without a star. He pointed out that it was difficult to recognize because of its faintness. William Herschel was able to identify a bright cluster of stars within the "nebula" during his observations; and, his son John Herschel expanded his father's findings in 1833 when using a more advanced telescope, he reported seeing a round, bright galaxy. Then in 1844, English Royal Navy officer, hydrographer, astronomer and numismatist William Henry Smyth extended the studies of M100, detailing it as a pearly white nebula and pointing out diffuse spots.
M100 is considered a starburst galaxy with the strongest star formation activity concentrated within a ring in its center, and with two tightly wound spiral arms attached to a small nuclear bar. Scientists believe star formation has been taking place there for at least 500 million years. As is usual for spiral galaxies in the Virgo Cluster, the rest of M100's disk sees a deficiency of both star formation and neutral hydrogen when compared to isolated spiral galaxies of similar type and size in other parts of the universe.
M100 appears very dim in the night sky. Its apparent magnitude of 9.4 means that, while it can be seen in very dark skies through small telescopes; it appears only as a very faint patch of light. Larger telescopes (200mm and larger) are needed to resolve more details. Imagers on the other hand can capture it quite readily using modestly sized equipment.
M100 comes into view above the eastern horizon in the early mornings of November. It then progresses to evening visibility in March. It is best observed during May when high in the sky where observers and imagers may look through the thinnest part of Earth's atmosphere. It remains visible throughout the summer until it disappears below the western horizon in September, not to return again until the early mornings of late November.