Tonight's Sky

Dave Leake's preview of 2019 sky events can be foundhere.  

For: December 31 – January 6

Happy New Year!  We have some wonderful events coming up, including a lunar eclipse in a couple of weeks.  You can find my 2019 preview on the planetarium web site under “Resources” then “Tonight’s Sky.”  I bet you’ve heard about this “Christmas comet” on social media.  Comet Wirtanen was discovered in 1948 and takes only five years to orbit the Sun, but it’s coming a little closer to us this time around.  People have seen the comet in binoculars.  It’s large but its surface brightness is low so it’s best seen in a dark sky (meaning without the Moon).  The problem is the comet is in a star poor constellation called Lynx.  Check back next week for how to locate it. 

For: January 7-13

We introduced Comet Wirtanen last week.  This Wednesday evening the comet is right next to the nose of Ursa Major, our Great Bear.  Try looking in binoculars above the Dipper’s bowl in the northeast.  The comet will move nightly, heading for a rendezvous with the Bear’s front legs in early February.  Look for a fuzzy cotton ball.  At Thursday’s CU Astronomical Society meeting (7pm, planetarium) we’ll preview the sky for 2019.  Watch early in the evening all week as the crescent Moon treks further eastward until Saturday when a nearly first quarter Moon is just below and left of Mars in the southwest.  Mars continues to fade as the Earth pulls away from it in its faster orbit.  

For: January 14-20

The planetarium opens to public audiences this weekend with the return of “Winter Prairie Skies,” “Cosmic Colors” and our Big Bird show.  The big event, however, happens Sunday night as we’ll experience a total lunar eclipse.   In the eclipse realm, this is it for us this year unless you travel.  The Moon enters the Earth’s shadow at 9:33pm.  It will be completely inside the shadow for about an hour starting at 10:41pm.  Unlike their solar counterparts, lunar eclipses is safe to view.  If you want to see the event through a telescope, the CU Astronomical Society will be at the planetarium beginning at 9:30pm.  This event is weather permitting.  Let see if the Moon takes on a reddish hue during totality.  

For: January 21-27

If you heard this full Moon is a “supermoon,” that is accurate but the change in apparent size of the Moon from its closest to its farthest point is something the human eye can’t detect.  In other words, “supermoons” aren’t that big of a deal, despite what you might read on social media.  If you see the Moon rising and it looks large, that’s an optical illusion.  Google the “moon illusion” for the story.  Even star constellations look larger near the horizon.  Friday morning, look before sunrise for Venus and Jupiter, side by side, in the southeast.  The star Antares will be right of the pair.  Each successive morning now Venus will get lower and Jupiter higher.  

For: January 28 – February 3

As the sky darkens, look eastward for the constellation Orion.  Three stars in a line fit within a large rectangle.  The three belt stars point towards the horizon at Sirius, the brightest nighttime star.  Look left of Sirius for the star Procyon.  The name means “Before the dog” as Procyon rises just before Sirius does, announcing the coming of Sirius.  These two stars and the shoulder of Orion (upper left in the rectangle) make our “winter triangle.”  The triangle isn’t an official constellation but it’s something to find in light polluted skies.  Friday, the planetarium welcomes Dr. May Berenbaum for our next science talk on spiders at 7pm.  Admission is $2 at the door.

See Dave Leake's "Prairie Skies" column in the Champaign-Urbana News-Gazette each Monday morning.