Pierre Méchain, one of Charles Messier’s colleagues, discovered the Pinwheel galaxy in 1781. Located 25 million light-years away from Earth in the constellation Ursa Major, M101 has an apparent magnitude of 7.9.
The giant spiral disk of stars, dust and gas is 170,000 light-years across — nearly twice the diameter of our galaxy, the Milky Way. M101 is estimated to contain at least one trillion stars.
https://www.nasa.gov/feature/goddard/2017/messier-101-the-pinwheel-galaxy"... M101 has a smaller apparent size of 30' by 27' — but that’s still as big as the Full Moon!...And M101 contains 11 nebulae bright enough to have their own NGC numbers — more than any other galaxy.
The most likely reason for M101’s record number of NGC objects is that astronomers believe M101 has undergone tidal interactions with dwarf galaxies in its group. The dwarf galaxy NGC 5477 is the leading suspect. Computer simulations of a close interaction between such a dwarf and a classic spiral galaxy generate a good approximation of M101’s appearance with a decidedly off-center core and far-flung spiral arms."
https://astronomy.com/magazine/news/2020/03/discover-the-secrets-of-the-northern-pinwheel-galaxyThe First time we worked on this fascinating galaxy it was acquired the data between Dec 2019 and May 2020. Stacking the sessions was a bit of a challenge due the differences presented in the rotation and seeing condition. Only one session was done with the filter Enhance but was enough to bring up a bit more details in the bright nebulas that are present around its arms.
Maurizio has done several other sessions of this galaxy this year and I hope to work it in the future because that data was done with Extreme and Enhance filters plus the Ra camera and bring more details of the nebulae in the galaxy. Its a magnificent galaxy that deserved a special attention and dedication.
Also impressive are the several galaxies present in the area with different shapes and forms, older and younger.
Process January 20th, 2021.
https://twitter.com/AstroOtus/status/1354795551817150495
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