Jupiter stars in planetary landscape
Jupiter rules the night this winter while Mars lingers in the sunset glow for another two months. Mercury meets Mars in February, and Saturn takes the evening sky from Jupiter in late spring. Venus is presently lost in the sun’s glow for more than two months, but it will reappear in the evening sky starting in late April.
Super bright Jupiter is now dominating both the evening and the night sky with its radiance until it sets around 3 a.m. During its time above the horizon, Jupiter’s intense light outshines all the bright stars of winter and sparkles three times brighter than Sirius, winter’s brightest star.
An easy way to locate Jupiter is to find winter’s classic constellation, Orion the hunter. Orion is currently found high in the south at 9 p.m. and there is no mistaking its pattern of four bright stars that outline the hunter’s distinctive hourglass shape. This stellar arrangement forms one of the sky’s most notable constellations of bright stars.
Looking to the center of Orion, three obvious stars in a row form this mythical figure’s belt. An imaginary line drawn upward though the belt stars leads to a pastel orange star named Aldebaran (a line drawn downward leads to Sirius). This is the marker star of Taurus and is considered the right eye of the bull. Extending the pretend line further upward leads to an extra “star” in Taurus — this is Jupiter.
Although this giant planet is now setting in the middle of the night, just like the stars, Jupiter will become visible slightly more to the west each evening because of Earth’s eastward — and faster — orbital motion around the sun. This small, daily westward shift is different, however, from the apparent westward movement of the stars, planets, moon and the sun across the sky each day resulting from Earth’s rotation.
Jupiter will be shining low in the western twilight by mid-May and by June it will be positioned too close to the sun to be seen. On June 19, Earth’s orbital motion places the sun between us and Jupiter. After mid-July, the planet will emerge into the eastern predawn sky, rising before 4 a.m. Jupiter will then be back in the eastern evening sky by the end of 2013. By that time, Jupiter’s own motion around the sun will have moved it one constellation of the zodiac eastward from Taurus to Gemini the twins.
Mars has been hanging on in the dusk sky since the end of last July. Its fast motion around the sun has moved it quickly enough eastward against the stellar background to compensate for its apparent westward shift in position due to Earth’s orbit. The result has been that Mars becomes visible at essentially the same altitude every evening in the west.
But not much longer. Earth’s motion has begun to prevail and now Mars will become visible slightly lower each successive evening. Nonetheless, Mars will continue to “hang around” for a short time. It is found low in the afterglow of sunset through the middle of March. A clear, unobstructed west to southwestern horizon and a pair of binoculars will most likely be necessary to find Mars.
Assisting in the search for Mars will be Mercury. The innermost planet creeps into the west-southwestern twilight sky at the end of January and becomes visible higher in that direction each evening through mid-February. After that, Mercury starts out lower each evening and is gone by the end of the month.
Mercury will appear closest to Mars on Feb. 8 and the two planets will appear in the same binocular field of view for a few days around that date. Be sure to start your search in a clear sky before 6 p.m. This hunt could be challenging! Remember that planets look like stars through binoculars. The best sight will be during the early evening of Feb. 11 when a thin crescent moon is above Mars and Mercury.
This appearance of Mercury in the evening sky is only one of three that will take place this year. Mercury will also be visible in the west-northwest after sunset from mid-May through the third week in June. Then it will have a poor appearance in the evening sky during September and October. In between these dates, Mercury will be found above the eastern horizon before sunrise.
Rings and more
Saturn and its rings are visible through early October. The Ringed Planet is against the stars of Libra the scales, so it remains low during the night as it arches from its current rising point in the east-southeast to its setting position in the west-southwest. Saturn is now rising before 1 a.m. but by the end of April, it will be visible all night long.
Of course, what makes Saturn so special when viewed through a telescope is its spectacular system of rings. The rings of this butterscotch-colored planet always offer a stunning view regardless of the size of the telescope. Saturn’s rings are open toward the Earth and will be tilted into our view all year. After mid-November, Saturn will be seen before sunrise above the east-southeastern horizon.
Through the first week in February, Venus is positioned very low near the southeastern horizon just before sunrise, but it is deep in the glare of dawn. Venus will appear to pass under the sun at the end of March from Earth’s viewpoint. Then in early April, it will pass close to Mars on the sky background but this will be an unseen event since the apparent positions of both planets will be very near the sun. However, by early May, Venus will start to be the evening “star” and remain so for the rest of the year.
Comets in 2013
Keep those binoculars nearby because there are two comets that have the possibility of becoming bright celestial objects this year. The first is Comet Panstarrs. It seems to be on track to be an impressive sight, but its brightness could be dulled by its position in the twilight sky.
Start looking for this comet above the western horizon 30 to 40 minutes after sunset on March 12. A thin crescent moon will be to its west that evening so the two could make a memorable sight.
Comet Panstarrs should continue to be visible through the first week of April. Each successive day it will come into view slightly more toward the northwest, reaching that point during the first week of April. If Comet Panstarrs doesn’t “pan” out, there’s another potentially bright comet coming in December.
Richard Monda is an astronomer living in the Capital Region.