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M90 & IC3583

Classification: Sprial Galaxy M90, NGC4569
Constellation: Virgo (VIR)
Object Location: Ra 12h 37m 37s Dec +13° 04’
Size & Distance: 9.5 x 4.4 Apx 60 Million light years

Date & Location: 04-18-2015 Little Blair Valley, CA.
Exposure: LRGB; 90, 45, 45, 45. All 15min. (bin 1x1)
Optics: Telescope Engineering Company APO180FL @ f/7.36 using an Astro-Physics 160FF, F/L 1325mm.
Mount: Astro-Physics 1200 GTO / ATS 10x36 pier.
Camera: FLI-MLx694 @-20c / CFW2-7 / FLI-Atlas focuser / Guided by SBIG ST-I / w OAG.
Filters: Astrodon G2 LRGB
Software: MaxImDL 6.08, Photoshop CS5, CCDStack 2.82, Topaz Labs.

Notes: Sky conditions: Poor seeing, Light wind, Temp, low 60’s
Cropped Image Field of view is 19.1 x 23.4 arcmin.
IC3583 1.8 x 0.9 an Irregular Galaxy just above M90

M90,  NGC 4569 is a spiral galaxy about 60 million light-years away in the constellation Virgo. It was discovered by Charles Messier in 1781. Messier 90 is a member of the Virgo Cluster and one of its largest and brightest spiral galaxies, with an absolute magnitude of around -22 (brighter than the Andromeda Galaxy). The galaxy is located approximately 1°.5 away from the subgroup centered on Messier 87. As a consequence of the galaxy's interaction with the intracluster medium in the Virgo Cluster, the galaxy has lost much of its interstellar medium. As a result of this process, which is referred to as ram-pressure stripping, the galaxy's interstellar medium and star formation regions appear severely truncated compared to similar galaxies outside the Virgo Cluster and there're even H II regions outside the galactic plane.

Consequently, the galaxy's spiral arms appear to be smooth and featureless, rather than knotted like galaxies with extended star formation, which justifies why this galaxy, along with NGC 4921 in the Coma Cluster has been classified as the prototype of an anemic galaxy