Leonine Galactic Triplets

Monday night I was able to take out the imaging telescope for the first time this year, after spots of bad weather and poor conditions the last few weeks. Fortunately, conditions were pretty good and I was able to get several images, including the following image of the charming collection of galaxies known as the Leo Triplet.

The two galaxies near the top were spotted by Charles Messier in 1780, and bear the Messier numbers 65 (left) and 66 (right) respectively. The bottom galaxy was faint enough to elude his small telescope and was discovered instead by Sir William Herschel (who also discovered the planet Uranus) in 1784. It has the NGC number 3628. These three galaxies form what is believed to be a physical group at a distance of about 35 million light-years.

Each of the three galaxies is roughly the size of our own Milky Way galaxy, and it seems likely that some or all of them have had close gravitational interactions in the past. M66 in particular appears to show signs of gravitational disturbance, visible in the slightly distorted shape of the top spiral arm in this image. It's a bit harder to tell with the other two, lying nearly edge-on to us as they do, although you can kind of make out that the dust lane running across NGC 3628 is bent, tell-tale evidence of past (and ongoing) interaction.

All three galaxies show pretty nice dust lanes, really, whether they're edge-on or more face-on to us.