What's Up - January 2016

What's Up for January? A meteor shower, a binocular comet, and the winter circle of stars!

Hello and welcome. I’m Jane Houston Jones from NASA’s Jet Propulsion Laboratory in Pasadena, California.

In case you missed last month’s Geminid and Ursid meteor showers, January 4th’s Quadrantids will either sizzle or fizzle for observers in the U.S. The shower may favor the U.S., or it could favor Europe, depending on which prediction turns out to be correct. The shower’s radiant, in the obsolete constellation Quadrans Muralis, is in a star-poor but familiar area in the northeast sky. It makes a triangle with Ursa Major and Ursa Minor – the big and little dippers. U.S. Observers should begin looking at 08:00 Universal Time – that’s midnight Pacific or 3 a.m. Eastern - and European observers should look 8 hours earlier at 00 UT. The peak should last about two hours, with rates of 120 meteors per hour predicted in areas with a dark sky.

In the middle of the month, midnight through pre-dawn will be prime time for viewing comet Catalina. It’s also near Ursa Major this month. It should be visible in binoculars if you have a dark sky, but a telescope would be ideal. Between the 14th and the 17th, the comet will pass by two stunning galaxies: M51, the Whirlpool galaxy and M101, a fainter spiral galaxy.

Winter is also the best time to view the constellation Orion in the southeastern sky. Even from the city, you’ll see that its stars have different colors. No telescope needed. Just look up a few hours after sunset. Orion’s shoulder star Betelgeuse is a red giant while its opposite knee is blue. And below the familiar belt stars is the Orion Nebula, a star-forming region, easily visible with binoculars.

The colorful stars of Orion are part of the Winter Circle of Stars. Let’s start with Orion’s blue star Rigel, and work clockwise to create the circle. At 6 o’clock, notice the brilliant white of Sirius, the brightest star in our northern hemisphere skies. Next up is faint yellow Procyon at 8 o’clock, and the colorful Gemini Twins Pollux and Castor at 10 o’clock. Brighter Pollux is faint orange and Castor is white. Yellow Capella appears at 12 o'clock. Finally at 2 o'clock stunning orange Aldeberan is near the Pleiades, in the constellation Taurus the bull. In the middle of our circle lies red Betelgeuse.

A star’s color reveals the star’s temperature and age. In a flame, the hottest part is blue, and the cooler parts are yellow and red. Stars work the same! The hotter a star, the more blue light it produces. The cooler the star, the more red light it produces. Medium-hot stars like our sun are yellow.

You can learn about all of NASA’s studies of the stars and much more at www.nasa.gov

That's all for this month. I'm Jane Houston Jones.