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06/04/2013 – Ephemeris – A cluster of not stars but galaxies

June 4, 2013 Comments off

Ephemeris for Tuesday, June 4th.  Today the sun will be up for 15 hours and 24 minutes, setting at 9:23.   The moon, half way from last quarter to new, will rise at 4:08 tomorrow morning.  Tomorrow the sun will rise at 5:58.

The constellation Virgo which contains the bright star Spica and for this and the last two years the planet Saturn is in a sparse region of the sky as far as stars go.  We are almost directly looking out the side of our Milky Way Galaxy.  That milky band has been banished to the northern horizon.  But while the stars may be few, we are also looking out past a gulf of 50 million light years to a great cluster of galaxies we call the Virgo Cluster.  The galaxies here count into the thousands and overflow Virgo itself into adjacent constellations.  I found that an 8 inch diameter telescope can easily pick up the brightest of them.  In its heart is a giant elliptical galaxy M87 which has a black hole of 6.6 billion sun masses.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

M87

This deep image of the Virgo Cluster obtained by Chris Mihos and his colleagues using the Burrell Schmidt telescope shows the diffuse light between the galaxies belonging to the cluster. North is up, east to the left. The dark spots indicate where bright foreground stars were removed from the image. Messier 87 is the largest galaxy in the picture (lower left).