Friday, December 13, 2013
By BERNIE REIM
(Continued from page 1)
This chart represents the sky as it appears over Maine during March. The stars are shown as they appear at 9:30 p.m. early in the month, at 9:30 p.m. at midmonth and at 8:30 p.m. at month’s end. Jupiter is shown in its midmonth position. To use the map, hold it vertically and turn it so that the direction you are facing is at the bottom.
Sky Chart Prepared by George Ayers
There are two comets visible in March, one of which could get as bright as second magnitude. Comet PanSTARRS, named after a telescope in Hawaii that is searching for potentially hazardous asteroids, will reach perihelion March 10, when it will get inside the orbit of Mercury at just 0.3 a.u. away from the sun. It will probably grow a nice tail by then since the pressure on it due to the solar wind will be about 100 times what it was just a month earlier when it was much farther out and moving slower. Look for the comet starting early in March low in the western evening sky half an hour after sunset.
It will be 10 degrees up or one fist at arm's length by March 12, when a beautiful slender waxing crescent moon will pass very close to the comet in the deepening twilight. This will create a great photo opportunity for us to better appreciate some of our close celestial neighbors.
Then continue to follow this comet for the next three months. It will get higher in the evening sky and pass near Polaris by the end of May. It will pass very close to our sister galaxy, the Andromeda, on April 4, creating another wonderful photo op, reminiscent of Comet Ikeya-Zhang's very close approach to this same galaxy exactly 11 years ago.
Our two largest planets, Jupiter and Saturn, will be the only planets visible in March. Jupiter is noticeably moving in direct or eastward motion again towards Gemini. It will remain in Taurus in March and form some interesting geometric shapes with the brighter stars in Taurus.
The other interesting phenomenon that is always visible at this time in the western sky about an hour after sunset is the zodiacal light. Creating a ring around our solar system in the ecliptic plane, this is interplanetary dust mostly from disintegrated comets that has gradually spiraled into the inner solar system. Forming a subtle haystack or pyramid of eerie light over the western horizon, you are seeing the sunlight bouncing off these particles.
The zodiacal light is actually the brightest thing in our solar system after the sun. It reflects more sunlight than Venus or Jupiter, if you could collect it into one spot. Your other good chance to see this subtle and rare phenomenon is during the fall about an hour before sunrise in the eastern sky. I have only seen it twice.
• March 4. Last quarter moon is at 4:53 p.m.EST.
• March 9. Comet PanSTARRS should become visible by now low in the western evening sky. You may need binoculars if it doesn't brighten as predicted.
• March 10. Daylight-Saving time starts at 2 a.m.
• March 11. New moon is at 3:51 p.m. EDT.
• March 12. Look for a waxing crescent moon near the comet tonight and tomorrow night.
• March 14. Albert Einstein was born on this day in 1879. He defined gravity by seeing it as the shape, or topography of the fourth dimensional space-time continuum within which everything is embedded.
Bernie Reim of Wells is co-director of the Astronomical Society of Northern New England.