Archive for April 16, 2018

04/16/2018 – Ephemeris – The Virgo cluster of galaxies

April 16, 2018 Comments off

Ephemeris for Monday, April 16th. The Sun rises at 6:56. It’ll be up for 13 hours and 32 minutes, setting at 8:29. The Moon, 1 day past new, will set at 9:16 this evening.

The stars around the constellation Leo and Virgo below and left of it feature relatively few stars, compared to those around Orion and the other winter constellations. That isn’t just a lot of blank sky, but beyond what can be seen with the naked eye in the region of southwestern Virgo, just to the lower left of the tail star Denebola of Leo is a vast cluster of galaxies that outnumber the stars of the same brightness in that direction. It is the Virgo Galaxy Cluster. Astronomers shorten the name to the Virgo Cluster. Two centuries ago the comet hunter Charles Messier swept this region with his small telescope and found many fuzzy bodies that could be confused with comets. He didn’t know what they were, but they sure weren’t comets, because they didn’t move against the stars.

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


Brighter members of the Virgo Cluster. Created using Stellarium.

Brighter members of the Virgo Cluster. Created using Stellarium. Open circles are galaxies, circles with crosses are globular star clusters, outlying members of our Milky Way galaxy. This image is from a few years ago – Saturn, above Spica, has moved on.