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View Full Version : A Bridge Too Far?



Jimi Lowrey
April 24th, 2013, 10:46 PM
NGC 5774 and NGC 5775 are a really stunning sight in most any telescope. There is a nice web page about this pair at Skyhound's site http://observing.skyhound.com/archives/may/NGC_5774.html

I have tried to see the faint bridge many times in the past with my old 25" reflector and never could get a good night to see it. There have been reports of it being seen in a 18" but over the years it has eluded me.

SDSS image
599

Last week I was observing in the area of East Virgo and I remembered this interacting pair on a night of excellent transparency and thought I would try for the bridge. At 375 X the pair was jaw dropping in the 48". I could see the faint bridge with averted vision and was surprised. I bumped up the power to 488X with a 10MM ZAO and the bridge was direct vision and almost went all the way with AV to the edge on NGC 5775. I was really excited to see it after many many years of striking out. I was able to see four galaxies in the field and did a drawing of the field.

NGC 5774
NGC 5775
IC 1060
SDSS J145355.82+033431.8 MAG 18.0V

601

If you get a chance to view this beautiful pair I highly recommended it in any size telescope and please let me know if you see the bridge that eluded me for years.

Ivan Maly
April 25th, 2013, 06:21 AM
Dramatic view! NED gives redshift-independent distance for -74 and -75 as 30.6+-4.5 and 21.4+-4.9 Mpc (+-SD over 4 and 5 measurements respectively). The arm in -74 is clearly extending asymmetrically, indicating gravitational distortion, but the "bridge" in this case is probably only as physical as in the case of M51, i.e. primarily a projection effect. There is an intriguing blue star cloud just SW of the NW tip of NGC 5775. It is pretty well aligned with the arm in NGC 5774 that forms the "bridge" to be its continuation. If so, the "bridge" clearly misses the target or passes right through it. Regardless, a great view from Earth.