230418 - M53 / NGC 5053 Binary Globular Clusters
in Coma Bernices
in Coma Bernices
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click image to enlarge
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ASTRO:
type=Globular Star CLuster mag=7.7 - M53 (brighter); 9.96 - NGC 5053 (fainter) const=Coma Bernices dist=58 k ly (M53); 57 k ly (NGC 5053) size=219 ly (M53); 177 ly (NGC 5053) IMAGE: location=EB Driveway BrtlCls=4 moon=0.4% (new) exposure=CMOS OSC, 43x180s (2.2h), Gain150 EQUIPMENT: camera=ZWO ASI2600MC-Pro optics=ES102 w0.8x rdcr, F=571mm, f/5.6 filter=Optolong L-Pro LPS mount=Celestron AVX guiding=Orion 60x240mm, ZWO ASi224MC SOFTWARE: acquisition=Stellarium, APT, PHD2, DSS processing=PhotoshopCC, RCAstro, APF-R, StarNet++, LrC |
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Making for a beautiful pairing of two (2) Globular Clusters within this single image field of view, the brighter Messier 53 (or M53) and the fainter NGC 5053 are a binary pair of magnificent "Sentinels of the Milky Way Galaxy". Being two (2) of the appx 143 known globular clusters in the Milky Way (there may be more as yet undiscovered), they are located less than 1° apart from each other, with the two having nearly the same distance modulus of appx 58,000 ly from us here on Earth. Working through the math, this corresponds to a spatial separation between them of appx 6500 ly.
M53 was discovered by Johann Elert Bode in 1775. It is one of the more outlying globular clusters in the Milky Way galaxy, being about 60,000 light-years away from the Galactic Center, and almost the same distance (about 58,000 light-years) from our Solar System. It is considered a metal-poor cluster, meaning the stars have a low abundance of elements other than hydrogen and helium—what scientists term metallicity. At one time, it was thought M53 was the most metal-poor cluster in the Milky Way. Today, its binary partner NGC 5053 holds that distinction. Measurements of the stars in the red giant branch of the cluster show that most of the stars found there are first-generation stars. That is, they did not form from gas recycled from previous generations of stars. This differs from most other globular clusters which are more dominated by second generation stars. The few second generation stars found in M53 are concentrated in its core region. Overall, the stellar composition of M53 is similar to that of other clusters found in the Milky Way halo, suggesting that M53's origin is from that galactic medium.
NGC 5053 was discovered by German-British astronomer William Herschel in 1784. He described it as, "an extremely faint cluster of extremely small stars, resolvable with an instrument 8' or 10′ diameter. Then in 1888, it was verified by Danish-Irish astronomer John Louis Emil Dreyer as he reported, "The cluster appeared very faint, pretty large, [having an] irregular round shape, growing very gradually brighter at the middle". Like its binary partner, NGC 5053 is a metal-poor cluster. As recently as 1995, it was considered the most metal-poor globular cluster in the Milky Way. The chemical makeup of the stars in NGC 5053 are more similar to those found in the Sagittarius Dwarf Spheroidal Galaxy (Kowal's Object) than to those found in the Milky Way halo. Along with the kinematics of the globular cluster as it moves through space, this suggests that NGC 5053 may have been stripped away from that dwarf galaxy.
Not visible in this image, but known through sensitive measurements made by professional scientific astronomers, there is a tidal bridge-like structure that appears to connect M53 with its very diffuse neighbor NGC 5053, as well as an envelope of what appears to be stellar debris surrounding both clusters. This tends to indicate a dynamic tidal interaction has occurred between the two clusters at some time in the past. With these two GC's apparent origins being from different sources, and yet also their being tidally locked together, makes for a very interesting pair of objects under study by the scientific community. This pair of "Sentinels" are currently thought to be singularly unique within our home Milky Way galaxy, since as-yet there have been no other binary clusters found within the galaxy.
M53 was discovered by Johann Elert Bode in 1775. It is one of the more outlying globular clusters in the Milky Way galaxy, being about 60,000 light-years away from the Galactic Center, and almost the same distance (about 58,000 light-years) from our Solar System. It is considered a metal-poor cluster, meaning the stars have a low abundance of elements other than hydrogen and helium—what scientists term metallicity. At one time, it was thought M53 was the most metal-poor cluster in the Milky Way. Today, its binary partner NGC 5053 holds that distinction. Measurements of the stars in the red giant branch of the cluster show that most of the stars found there are first-generation stars. That is, they did not form from gas recycled from previous generations of stars. This differs from most other globular clusters which are more dominated by second generation stars. The few second generation stars found in M53 are concentrated in its core region. Overall, the stellar composition of M53 is similar to that of other clusters found in the Milky Way halo, suggesting that M53's origin is from that galactic medium.
NGC 5053 was discovered by German-British astronomer William Herschel in 1784. He described it as, "an extremely faint cluster of extremely small stars, resolvable with an instrument 8' or 10′ diameter. Then in 1888, it was verified by Danish-Irish astronomer John Louis Emil Dreyer as he reported, "The cluster appeared very faint, pretty large, [having an] irregular round shape, growing very gradually brighter at the middle". Like its binary partner, NGC 5053 is a metal-poor cluster. As recently as 1995, it was considered the most metal-poor globular cluster in the Milky Way. The chemical makeup of the stars in NGC 5053 are more similar to those found in the Sagittarius Dwarf Spheroidal Galaxy (Kowal's Object) than to those found in the Milky Way halo. Along with the kinematics of the globular cluster as it moves through space, this suggests that NGC 5053 may have been stripped away from that dwarf galaxy.
Not visible in this image, but known through sensitive measurements made by professional scientific astronomers, there is a tidal bridge-like structure that appears to connect M53 with its very diffuse neighbor NGC 5053, as well as an envelope of what appears to be stellar debris surrounding both clusters. This tends to indicate a dynamic tidal interaction has occurred between the two clusters at some time in the past. With these two GC's apparent origins being from different sources, and yet also their being tidally locked together, makes for a very interesting pair of objects under study by the scientific community. This pair of "Sentinels" are currently thought to be singularly unique within our home Milky Way galaxy, since as-yet there have been no other binary clusters found within the galaxy.