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THe All-Sky Chart for August 2012 (Tristate Astronomers / July 30, 2012) |
The August Sky
As summer winds down, some familiar star patterns make their return to the early evening skies in the east, as others fade below the western horizon. Face east to see the great square of Pegasus the Flying Horse, rising earlier each night throughout the month.
Turn around to face west and look a little to your right to see the Big Dipper high in the northwestern sky. The outside edge of the cup will be facing down toward the north while the handle will be pointing back to the south.
Finally, look almost directly overhead to spot the bright white star, Vega, which is part of the constellation Lyra the Harp. This is also the brightest star in the Summer Triangle, which is completed with the stars Altair, found in Aquila the Eagle, and Deneb, found in Cygnus the Swan.
For a more detailed tour of the night sky check out Skylights, the monthly podcast tour of the night sky, downloadable at http://www.antpod.com/.
The August Solar System
Evening Planets
MARS, the red planet, finally catches Saturn and Spica about half way through the month. Moving in from the west, Mars will pass between golden Saturn and blue Spica on the nights of Aug. 13-14.
SATURN will be paired with Spica all month and will shine at 0.8 magnitude, just a little brighter than 1.0 magnitude Spica. Saturn moves slowly to the east throughout the month and will be slightly above Spica in the sky.
NEPTUNE will rise in the evening, but won’t be high in the sky until mid-morning. As always, Neptune can not be spotted with the naked eye.
URANUS also rises in the evening and reaches its highest point mid-morning as well. As with Neptune, a telescope or binoculars are necessary to spot this giant planet.
Morning Planets
JUPITER rises above the eastern horizon after midnight at the beginning of the month and around midnight near the end of the month and shines at a -2.3 magnitude.
VENUS, which is quickly moving away from Jupiter to the east, does not rise until midmorning, around 3 a.m., and reaches greatest elongation on August 15.
MERCURY rises about 1 ½ hours before the sun at midmonth, but will rise later and later until it’s rising 20-30 minutes before the sun at month’s end.
Sun and moon
On Aug. 1, sunrise is at 6:10 a.m. and sunset at 8:24 p.m., for 14 hours and 14 minutes of daylight. By Aug. 31, sunrise isn’t until 6:38 a.m., with the sun setting at 7:44 p.m. for 13 hours and 6 minutes of daylight - a 68-minute decrease from the beginning of the month.
On Aug. 20, the sun leaves Cancer the Crab and enters the constellation Leo the Lion. The change is caused by Earth’s revolution around the sun. The sun seems to line up with distant background stars from our viewpoint here on Earth, so the sky changes by seasons and months.
Full moon is Aug. 2, last quarter on Aug. 9, new moon on Aug. 17, and first quarter on Aug. 24. We’ll also have a special second full moon this month on Aug. 31. This second full moon within one calendar month is what is known as a blue moon, and they happen once every two to three years. Though the name may suggest a change in color, this is not the case. The moon will appear the same color as it would on any night with the same atmospheric conditions.
Special events
• The Perseids meteor shower will peak this year on the night of Saturday, August 11 into the morning hours of Sunday August 12. The Perseids often have long trains and can reach peaks of over 50 meteors per hour. While the Perseids will make for great viewing here on Earth, an even more exciting event will be taking place this month, millions of miles away on Mars.
• The Mars Science Laboratory rover, Curiosity, will be delivered to the surface of Mars in the early morning on Monday Aug. 6, in a land formation known as the Gale Crater.
High-resolution video of portions of the descent will be taken as the rover is lowered to the landing site via rockets, parachute and finally, sky crane.
After approximately four days of testing of the rover’s systems and surroundings, Curiosity will set out on its mission to help achieve the four main goals of the Mars Exploration Program. These include sampling the environment to determine whether conditions ever existed on Mars that were conducive to life, characterization of the climate and geology of Mars, and to prepare for human exploration of the red planet.
If all goes according to plan Curiosity’s primary mission will last for almost two Earth years, and will take the rover up to twelve miles from its landing site. This will be another big step toward the goal of eventually sending a manned mission to Mars. For more information on this mission visit http://mars.jpl.nasa.gov/msl/.
William Brish Planetarium/Tristate Astronomers
The William Brish Planetarium will re-open in mid-August. For more information, visit www.wbplanetarium.weebly.com.
The next meeting for the TriState Astronomers will be held at the William Brish Planetarium on Sept. 19 at 7:30 p.m. All are welcome! For more information, visit http://www.tristateastronomers.org/.
