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The Sky This Week, 2012 April 17 - 24

Look up for dark skies!
marsc8_120414_0248small.jpg satc8_120414_0423small.jpg

Mars, 2012 April 14, 02:48 UT 

Saturn, 2012 April 14, 04:23 UT

The Last Orbit for Discovery
Imaged from the U.S. Naval Observatory, 2012 April 17

The Moon returns to the early evening sky during the latter part of this week. New Moon occurs on the 21st at 3:18 am Eastern Daylight Time. You might be able to catch your first glimpse of her thin waxing crescent on the 22nd as she perches just three degrees north of Jupiter low in the western sky about half an hour after sunset. You should have little trouble spotting her over the next several nights as she makes her way past dazzling Venus. The two are closest together on the 24th, when the Moon is some six degrees to the south of the brilliant planet.

You have until the night of the 20th to make your observations to contribute to the "Globe At Night" campaign. So far the program has amassed about 11,000 observations of the sky from people all around the world. The goal is to collect 15,000 observations to map the distribution of bright and dark nighttime skies throughout the world. To add to the awareness of the dark sky as a resource and natural wonder, the International Dark-Sky Association is observing International Dark-Sky Week, an event created in 2003 by a Virginia high-school student. Both events wrap up on the evening of the 20th, but the spirit of sky awareness that they hope to inspire should last a lifetime for those who take the time to participate. All of these events are part of a world-wide celebration of Global Astronomy Month, which will culminate on April 28th with Astronomy Day. We’ll have more details on activities for this fun family event next week.

If the weather is clear on the early morning of the 22nd, head to a dark location to observe the Lyrid meteor shower. This display is the product of Comet Thatcher (C/1861 G1), and is noted for occasional outbursts in activity. This year it is expected to peak at around 2:00 am on the east coast, with up to 18 to 20 meteors visible per hour coming from a point in the sky a few degrees away from the bright star Vega. After a lull of several months, it is the first shower of the building summer of meteor displays.

You can still catch Jupiter this week in the bright twilight of the western sky, but you’ll have to act fast and have a clear western skyline. By the week’s end he’s only five degrees above the horizon at 8:30 pm, and he sets by around 9:00. He will slip behind the Sun in another few weeks, returning to the morning sky in early June.

Dazzling Venus still lights up the early evening sky, but her time is now beginning to run out. By the end of the week she slowly begins to set earlier each night. Soon this will turn into a headlong plunge toward the Sun, and by early June she will be gone, crossing Old Sol’s face on June 5th and then leaping into the morning sky afterward. If you look at her now with a small telescope she will present a thick crescent phase. Over the next few weeks this crescent will become much thinner, but the apparent diameter of her disc will grow dramatically. This is the best time to watch her change her appearance through the eyepiece.

Ruddy Mars continues to loll among the stars of Leo, the Lion, just east of the bright star Regulus. Mars has begun a slow drift eastward after reaching his second stationary point last week. The red planet will slowly seem to pick up speed over the next few weeks as he begins a frantic race to outpace the Sun. He’ll travel a third of the way around the sky by the time he starts slipping into twilight by the year’s end. You can still see quite a bit of detail with a modest telescope pointed at his shrinking disc, but these features will rapidly become more difficult to glean in another few weeks.

Saturn, just past opposition, rises to prominence in the late evening hours along with the bright star Spica in the constellation Virgo. I never tire of gazing at this distant world with its mysterious rings, and now that he rises over the roofline of my house at a decent hour he’ll be garnering more of my attention with the telescope. I am often accused of trickery whenever I show Saturn to friends and visitors. His strange appearance always elicits "oohs" and "aahs" from almost everyone who glimpses him. I’m looking forward to showing him off until well into the summer.

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