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Monthly Messier
Star-Hop; May #3 This
month we go with Messier 49 and Messier 61,
both of which are galaxies located in the constellation Virgo.
Before tackling these star-hops, it is important to remember that the
Springtime brings us that part of the sky known as "the Realm of the Galaxies." In practical terms, this means that
if you are observing in the area of the constellations of Virgo,
Coma Berenecies, Canes Venatici, or Ursa Major, if
you see one galaxy, you'll see a lot of galaxies. This also means that
it's relatively easy to get lost if you don't pay attention to where you
are in the sky and where your telescope is pointed. Star-Hop #1. M49, NGC
4472
Star-Hop #1. M49,
NGC 4472. Located in the constellation Virgo,
M49 is a relatively bright,
8.4 magnitude galaxy located just south of a line between the prominent
star Vindamiatrix and the star Nu Virginis. Starting at Vindamiatrix, extend an imaginary line
from Vindamiatrix to the star
Nu Virginis. About 8 degrees, or a little
less than half way from Vindamiatrix
to Nu Virginis, extend a line
southwest for less than one degree, or the distance spanned by your little
finger against the night sky. Here, in a low power telescope or binoculars
you'll find M49 as the brightest
of a number of galaxies located
in this region of Virgo. In
the Atlanta Astronomy Club's 20 inch reflector, and at moderate power,
M49 appears small and round in appearance. Its nucleus predominates and is significantly
brighter than its halo. At high
power, the halo is much more pronounced, and appears to be somewhat flattened. Star-Hop #2. M61,
NGC 4303. Our last Messier object is the galaxy M61.
This 9.6 magnitude galaxy is located about 4 degrees south-southwest of
M49. However, for this final Messier star-hop, we'll start at the star
Porrima, Gamma Virginis. From Porrima,
extend an imaginary line to the star Omicron
Virginis. M61 is a little
more than halfway along this line to Omicron
Virginis, and just slightly to the northeast. Search this area in
the low power view of a telescope or a set of binoculars. Most of the
Virgo galaxies are located to the north of M49,
so if you find a bright galaxy in this area, it is M61.
Using the club's 20 inch reflector at low magnification, M61 appears to have a generally round halo with a stellar nucleus
visible in averted vision. At high power the nucleus is visible in direct
vision, and the halo appears to have some mottling.
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