OBSERVER’S CHALLENGE* – June, 2023
by Glenn Chaple
NGC 5774/5 Galaxies in Virgo (NGC 5774 Magnitude 12.1, Size 3.0’ X 2.4’; NGC 5775 Magnitude 11.4, Size 4.2’ X 1.0’)
About 2 degrees northeast of the 4th magnitude star 109 Virginis is the interacting galactic pair NGC 5774 and NGC 5775. Both are spirals, the former being somewhat face-on, while the latter is basically edge-on. Their difficulty for visual observation is evidenced by the fact that the brighter of the two, NGC 5775, was designated as a Class III object (Very Faint Nebulae) by William Herschel, who discovered it in 1786. The even fainter NGC 5774 remained undetected until the mid-1800s when the Irish engineer/astronomer Bindon Stoney spotted it with William Parson’s great 72-inch reflecting telescope (the “Leviathon of Parsonstown”).
While NGC 5774/5 can be captured visually with today’s smaller but optically superior instruments, you’ll need reasonably dark skies if you expect to view them with an 8 to 10-inch scope. Start with the brighter NGC 5775, which is located at 2000.0 coordinates RA 14h53m57.7s, Dec +3o32’40.1”. If you find it, NGC 5774 should appear as a fainter roundish glow 4.5 arc-minutes to its northwest. Even knowing exactly where to look directly or with averted vision, I saw neither with my 10-inch f/5 reflector under magnitude 5 suburban skies. Most guides assign NGC 5775 a magnitude of around 11.4. However, Burnham’s Celestial Handbook gives it a magnitude of 12.3, which would be more in keeping with a Class III Herschel object (and a handy excuse for my being unable to see it with my 10-inch!). Greg Crinklaw’s Skyhound website (observing.skyhound.com) agrees with Burnhan’s magnitude for NGC 5775 and lists NGC 5774’s as 12.8. Suffice it to say, these galaxies will challenge the experienced visual observer.
Image by Mario Motta