Jupiter, Moon and Pleiades: together and high up

Event Date: January 20th

Time: 8:00 PM

Brief

   We have an interesting trio to witness this evening, although one of them will be somewhat "washed-out" by another: Jupiter, the Pleiades star cluster, and the waxing gibbous Moon, which is bright enough to make the Pleiades harder to see with the eye.  Although this is unfortunate, the cluster is still easily visible in binoculars, and a wide-field for a telescope.  If you can see the Pleiades with the eye however, viewing the three is fun to do.  Try doing so when all three are near transit, at the time above, and shown below.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   We are fortunate to see all three of these very high, as seen from our latitude.  At latitudes in the southern U.S., and northern Mexico, the trio is seen at or very close to zenith for each time they group.  Which latitudes see Jupiter at its highest in the sky depends where the planet is in the sky on a coordinate basis; this of course, varies from month to month, and more obviously from year to year.  The Pleiades, being fixed, will always be seen high as seen from our latitude.  As for the Moon, it and Jupiter often pair up, whether it be north of the celestial equator (not shown) or south of it.  Jupiter's 12-year cycle through the sky, along with its change of direction against the stars as seen from Earth, means that each time the Moon is seen to "catch up" with it, the separation varies: sometimes a few degrees apart, sometimes very close.  Every so often, for a few Moon-cycles in a row, it occults the planet, seen from certain parts of the world-- time zone and latitude depending.

   Enjoy the three, and if you miss it because of poor weather, the next one is seen February 17th.  The configuration will happen for the next few months, until Jupiter starts to pull away far enough from the Pleiades late in the year.