Springtime. Galaxies. For deep sky observers the two words are inseparably linked. Looking out in the direction of the Virgo-Coma Berenices border with a 8" or larger scope the sky is filled with a mass of glowing spheres and spirals-the "Realm of the Nebulae."
This region is the center of the great Virgo cluster of galaxies, which at a distance of roughly 40 million light years is the nearest rich aggregation of galaxies in the sky. The Virgo cluster thins out as it stretches north into Coma Berenices, Canes Venatici and Ursa Major. A southern arm heads down into Hydra and Centaurus. The combined "cluster of clusters" is dubbed the local supercluster and probably includes our own local group of galaxies on the outskirts.
For amateur observers the task of attacking the Virgo cluster is daunting. Where do you begin and how do you avoid getting lost in the hundreds of galaxies visible in an 8" scope and the thousands of galaxies visible in a 17.5" scope? Probably the best place to start is at the core of the cluster, roughly midway between 3rd magnitude Epsilon Virginis (Vindemiatrix) and 2nd magnitude Beta Leonis (Denebola). Sweeping this area should quickly bring up the bright pair of ellipticals M84 and M86. Heading east and north is a remarkable curving chain of galaxies known as "Markarian's Chain" which ends over the Coma border at M88. I find it easiest to simply "galaxy hop" from one object to the next in the chain. All observations below were made with my 17.5" from dark skies at Fiddletown in the Sierra foothills of Northern California.
M84 and M86 form a striking low power pair of ellipticals at 17' separation. Both appears very bright, moderately large, almost round, with intense cores and very small bright nuclei. Their halos gradually fade into the background. I find that M86 is slightly larger and more oval than M84 but has an overall slightly lower surface brightness.
Forming an equilateral triangle to the south with M84 and M86 is NGC 4388. This edge-on spiral appears as a moderately bright streak oriented east-west with a brighter core and thin extensions. The exact center of this 17' triangle is marked by another galaxy, NGC 4387. Although much smaller than its brighter neighbors, NGC 4387 appears moderately bright with a small bright core. The halo is slightly elongated NW-SE and a mag 13 star lies 2' NNW. The challenging galaxy IC 3303 can be found 8.4' WNW of NGC 4388. With the 17.5" it appears very faint, small and slightly elongated and can only be held steadily with averted vision.
Heading east of NGC 4388 by 11' will bring you to NGC 4413. This fairly faint system is slightly elongated roughly north-south and appears slightly brighter along its major axis. A mag 13 star shines just 40" north. Now, turning 13' northeast will bring you to NGC 4425. I logged this spiral as moderately bright but fairly small. It is noticeably elongated SW-NE and contains a small brighter core. A mag 13.5 star is about 1' off the west side.
Next on our tour is striking pair of galaxies, NGC 4435 and NGC 4438, sometimes referred to as "The Eyes". You'll find this pair 20' north of NGC 4425 or a similar distance east of M86. NGC 4435 is a bright oval in my 17.5" and is sharply concentrated with a bright core and a stellar nucleus. NGC 4438 lies just 4.5' SSE. This spiral is elongated north-south and although quite bright, its core is not as prominent as NGC 4435.
Returning back to M86, you'll find an edge-on system, NGC 4402 just 10' north. The elongation is in an east-west direction with a major axis of 3.0' length. There is only a slight concentration with no distinct core or nucleus.
We need to head east-northeast about 20' from the NGC 4435/4438 duo to another pair of galaxies, NGC 4458 and NGC 4461. NGC 4458 is a moderately bright elliptical appearing only 45" diameter. It contains a small bright core and a faint stellar nucleus. A mag 12 star is located about 2' east. Just 3' northeast is NGC 4461, a fairly bright spiral elongated north-south with a bright, compact core.
We now continue northeast, crossing over the Coma Berenices border to NGC 4473. This is one of brighter galaxies in our Virgo-Coma tour which was missed by Messier. This high surface brightness spiral is elongated roughly east-west and contains a small but intense core highlighted by a stellar nucleus. Another 13' north will bring us to NGC 4477. This is another fairly bright galaxy about 2.0'x1.5' in size with a slight north-south elongation. The small core is quite bright and contains a stellar nucleus. It also forms a wide pair with the much fainter NGC 4479 8' southeast.
About 25' north of NGC 4477, you'll run into a trio of galaxies, NGC 4459, NGC 4468 and NGC 4474. NGC 4459 is another bright galaxy missed by Messier. It is evenly concentrated down to a bright intense core and a stellar nucleus. The halo is slightly elongated roughly east-west. Located 9' NE is faintest of this trio, NGC 4468. Even in a 17.5" it appears faint and fairly small with only a weak concentration. The last of our trio is NGC 4474 another 6' east. This moderately bright galaxy is only 1.0' diameter but contains a very small bright core. The halo is extended in a 2:1 ratio WSW-ENE
We finally end our tour of the Virgo Mainline by continuing northeast until running into M88 or NGC 4501. This striking galaxy is very bright and quite large, with a halo measuring at least 5.0'x2.0' and a brighter core containing an intense nucleus. A pair of mag 12 stars at 30" separation are embedded at the southeast end.