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The Sky This Week, 2014 March 4 - 11

Time to "Spring Forward"!
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The Moon: Eastern "shore" of Mare Imbrium
Imaged 2014 FEB 8


The Moon waxes in the evening sky this week. First Quarter occurs on the 8th at 8:27 am Eastern Standard Time. Luna’s crescent quickly climbs from the western horizon to join the stars of the Great Winter Circle. Look for Luna less than two degrees above the bright star Aldebaran on the evening of the 6th. On the evenings of the 9th and 10th she’ll be in the vicinity of bright Jupiter. She ends the week as a bright gibbous moving into the rising springtime constellations.

The 9th is the second Sunday in March, which means that it is time for most of us in the U.S. to advance our clocks by one hour to begin keeping Daylight Time. The change officially takes place at 2:00 am local time throughout the country except in Arizona and Hawai’i. This means that many of us will lose an hour of sleep over the weekend, but for stargazers it means that our favorite star patterns of the winter sky and the bright planet Jupiter get something of a reprieve from their headlong flight toward the west. Before you rush to Tweet your pleasure or displeasure over this annual ritual please note that the U.S. Naval Observatory has nothing to do with this inconvenience. The rules governing Daylight Time, time zones, and local observance of time are legislated by Congress and implemented by the Department of Transportation. The current system is a result of the Energy Policy Act of 2005. We will stay on Daylight Time until the first Sunday in November, which falls on the 2nd in 2014. You’ll get your hour of sleep back then. A brief history of Daylight Time in the U.S. may be found here.

This will be another great week to observe the Moon during her waxing phases. She climbs to her highest declination near the time of First Quarter, and owners of small telescopes can take advantage of this and spend many pleasant hours exploring her battered landscape. Each night brings new features into view along the "terminator", the line separating the lit hemisphere from the dark. During the crescent phases the scene is dominated by the broad, relatively flat lunar "seas". By the time of First Quarter the chaotic crater fields of the southern highlands come into view, bearing mute testimony to the incredible bombardment that the Moon and planets suffered during the early formation of the solar system. Most of these craters are dozens to hundreds of miles across and were blasted out by thousands of the "planetessimals" that roamed interplanetary space some four billion years ago. Very few of these impacts survive on the Earth thanks to erosion and plate tectonics, but the lifeless Moon will keep those scars for billions of years to come.

As mentioned above, setting the clocks ahead one hour effectively pushes rise and set times of celestial objects back by an hour. This is a boon to skywatchers who like to observe the evening sky, and especially those of us who enjoy Orion and his cohorts. For me the real beneficiary is Jupiter, which now gets an extra hour near the meridian and the best viewing conditions from my yard. As most of you can probably tell the giant planet is one of my favorite imaging targets, and the best pictures come from the time when Jupiter is highest in the sky. I’ll now have a bit of "extra" time to set up my scope and photograph him at his best, even after my usual after-work activities. Take advantage of this aspect of Daylight Time while you can. He won’t slow his inexorable path toward the Sun.

Daylight Time means that ruddy Mars has something of a setback in his journey to the evening sky, since once again he won’t rise until around 10:00 pm. However, he reached the first stationary point in his current apparition on March 1st, and has begun his retrograde loop as he approaches opposition next month. Once he picks up speed in this loop he will begin to rise five to six minutes earlier each night, so he’ll begin to steal some of Jupiter’s late-night thunder. He’ll also begin to close the gap with his nearby stellar neighbor Spica. He’ll pass due north of the star in another two weeks.

Daylight Time briefly pushes Saturn out of the evening sky. By the end of the week he rises just before midnight, so the best time to see him is before dawn. However, with Daylight Time you won’t have to get up at around 5:00 am to see him. You can grab a good look at him at around 6:00 am instead!

The same holds true for dazzling Venus, low in the southeast as morning twilight begins. She also takes advantage of daylight Time and is well-placed for viewing at around 6:00 am. You’ll have no trouble finding her so long as you have a clear view to the southeast. By the end of the week she forms a long line with the stars Vega and Altair, two stars of the Summer Triangle, so take heart: warmer weather is well on its way!

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