SUNSET: 
0
Photographer:
Jon Greif
Location of Photo:
Alpine, CA, USA
Date/Time of photo:
June 30 - July 1, 2023 between 10 pm and 3 am PDT
Equipment:
Takahashi FSQ-85ED with 1.01x flattener/reducer. ZWO ASI533MC Pro imaging camera. Optolong L-Pro filter. Rainbow Astro RST-135 Mount. ZWO 30mm Mini Guide Scope with ZWO ASI290 Mini guide camera. ASIAIR Plus controller. Processed in Pixinsight 1.8.9.
Description:
These two galaxies are far far away, 12 million light-years distant toward the northern constellation Ursa Major (the Great Bear). Above, with grand spiral arms and bright core is spiral galaxy M81, some 100,000 light-years across. Below, marked by red gas and dust clouds, is irregular galaxy M82. The pair have been locked in gravitational combat for a billion years. Gravity from each galaxy has profoundly affected the other during a series of cosmic close encounters. Their last go-round lasted about 100 million years and likely raised density waves rippling around M81, resulting in the richness of M81's spiral arms. M82 was left with violent star forming regions and colliding gas clouds so energetic the galaxy glows in X-rays. In the next few billion years, their continuing gravitational encounters will result in a merger, and a single galaxy will remain. [Discussion from NASA Science.] The image was from our new backyard in Alpine, 4.25 hours of exposure time two nights ago.
