Bode's Galaxy -- Messier 81 in UMa
Captured 23 April 2022, ~22:00 hrs ET, Springfield, VA, USA. Bortle 8 skies, Celestron 8 inch SCT at f/6.3 (eff. fl 1290mm), Orion Atlas AZ/EQ-G Pro mount. QHY 294M Pro camera @ -10C, bin 1, exposure 60 seconds, gain 2100, stack of 10 subframes, no calibration frames subtracted. Baader Luminance filter. Reprocessed in Siril and PS on 25 May 2023.
Clouds: partly cloudy
Seeing: avg
Transparency: avg
Moon phase: quarter
FOV: 30 x 24 arcmin.
Resolution: 0.9 arcsec/pixel.
Appearance: Face-on spiral galaxy with two arms.
From Wikipedia:
Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a grand design spiral galaxy about 12 million light-years away, with a diameter of 90,000 light years, in the constellation Ursa Major. Due to its proximity to our galaxy, large size, and active galactic nucleus (which harbors a 70 million M☉ supermassive black hole), Messier 81 has been studied extensively by professional astronomers. The galaxy's large size and relatively high brightness also makes it a popular target for amateur astronomers. In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst.
Messier 81 was first discovered by Johann Elert Bode on 31 December 1774. Thus, it is sometimes referred to as "Bode's Galaxy". In 1779, Pierre Méchain and Charles Messier reidentified Bode's object, hence listed it in the Messier Catalogue.
Most of the emission at infrared wavelengths originates from interstellar dust. This interstellar dust is found primarily within the galaxy's spiral arms, and it has been shown to be associated with star formation regions. The general explanation is that the hot, short-lived blue stars that are found within star formation regions are very effective at heating the dust and thus enhancing the infrared dust emission from these regions.
It is estimated M81 has 210 ± 30 globular clusters. In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst.
Only one supernova has been detected in Messier 81. The supernova, named SN 1993J, was discovered on 28 March 1993 by F. García in Spain. At the time, it was the second brightest supernova observed in the 20th century, peaking at an apparent magnitude of 10.7. The spectral characteristics of the supernova changed over time. Initially, it looked more like a type II supernova (a supernova formed by the explosion of a giant star) with strong hydrogen spectral line emission, but later the hydrogen lines faded and strong helium spectral lines appeared, making the supernova look more like a type Ib.
Moreover, the variations in SN 1993J's luminosity over time were not like the variations observed in other type II supernovae, but did resemble the variations observed in type Ib supernovae. Hence, the supernova has been classified as a type IIb, a transitory class between type II and type Ib. The scientific results from this supernova suggested that type Ib and Ic supernovae were formed through the explosions of giant stars through processes similar to those taking place in type II supernovae. Despite the uncertainties in modeling the unusual supernova, it was also used to estimate a very approximate distance of 8.5 ± 1.3 Mly (2.6 ± 0.4 Mpc) to Messier 81. As a local galaxy, the Central Bureau for Astronomical Telegrams (CBAT) tracks novae in M81 along with M31 and M33.
Messier 81 is the largest galaxy in the M81 Group, a group of 34 in the constellation Ursa Major. At approximately 11.7 Mly (3.6 Mpc) from the Earth, it makes this group and the Local Group, containing the Milky Way, relative neighbors in the Virgo Supercluster.
Gravitational interactions of M81 with M82 and NGC 3077 have stripped hydrogen gas away from all three galaxies, forming gaseous filamentary structures in the group. Moreover, these interactions have allowed interstellar gas to fall into the centers of M82 and NGC 3077, leading to vigorous star formation or starburst activity there.
Bode's Galaxy -- Messier 81 in UMa
Captured 23 April 2022, ~22:00 hrs ET, Springfield, VA, USA. Bortle 8 skies, Celestron 8 inch SCT at f/6.3 (eff. fl 1290mm), Orion Atlas AZ/EQ-G Pro mount. QHY 294M Pro camera @ -10C, bin 1, exposure 60 seconds, gain 2100, stack of 10 subframes, no calibration frames subtracted. Baader Luminance filter. Reprocessed in Siril and PS on 25 May 2023.
Clouds: partly cloudy
Seeing: avg
Transparency: avg
Moon phase: quarter
FOV: 30 x 24 arcmin.
Resolution: 0.9 arcsec/pixel.
Appearance: Face-on spiral galaxy with two arms.
From Wikipedia:
Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a grand design spiral galaxy about 12 million light-years away, with a diameter of 90,000 light years, in the constellation Ursa Major. Due to its proximity to our galaxy, large size, and active galactic nucleus (which harbors a 70 million M☉ supermassive black hole), Messier 81 has been studied extensively by professional astronomers. The galaxy's large size and relatively high brightness also makes it a popular target for amateur astronomers. In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst.
Messier 81 was first discovered by Johann Elert Bode on 31 December 1774. Thus, it is sometimes referred to as "Bode's Galaxy". In 1779, Pierre Méchain and Charles Messier reidentified Bode's object, hence listed it in the Messier Catalogue.
Most of the emission at infrared wavelengths originates from interstellar dust. This interstellar dust is found primarily within the galaxy's spiral arms, and it has been shown to be associated with star formation regions. The general explanation is that the hot, short-lived blue stars that are found within star formation regions are very effective at heating the dust and thus enhancing the infrared dust emission from these regions.
It is estimated M81 has 210 ± 30 globular clusters. In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst.
Only one supernova has been detected in Messier 81. The supernova, named SN 1993J, was discovered on 28 March 1993 by F. García in Spain. At the time, it was the second brightest supernova observed in the 20th century, peaking at an apparent magnitude of 10.7. The spectral characteristics of the supernova changed over time. Initially, it looked more like a type II supernova (a supernova formed by the explosion of a giant star) with strong hydrogen spectral line emission, but later the hydrogen lines faded and strong helium spectral lines appeared, making the supernova look more like a type Ib.
Moreover, the variations in SN 1993J's luminosity over time were not like the variations observed in other type II supernovae, but did resemble the variations observed in type Ib supernovae. Hence, the supernova has been classified as a type IIb, a transitory class between type II and type Ib. The scientific results from this supernova suggested that type Ib and Ic supernovae were formed through the explosions of giant stars through processes similar to those taking place in type II supernovae. Despite the uncertainties in modeling the unusual supernova, it was also used to estimate a very approximate distance of 8.5 ± 1.3 Mly (2.6 ± 0.4 Mpc) to Messier 81. As a local galaxy, the Central Bureau for Astronomical Telegrams (CBAT) tracks novae in M81 along with M31 and M33.
Messier 81 is the largest galaxy in the M81 Group, a group of 34 in the constellation Ursa Major. At approximately 11.7 Mly (3.6 Mpc) from the Earth, it makes this group and the Local Group, containing the Milky Way, relative neighbors in the Virgo Supercluster.
Gravitational interactions of M81 with M82 and NGC 3077 have stripped hydrogen gas away from all three galaxies, forming gaseous filamentary structures in the group. Moreover, these interactions have allowed interstellar gas to fall into the centers of M82 and NGC 3077, leading to vigorous star formation or starburst activity there.