- Recorder Online - http://www.berthoudrecorder.com -
Earthsky Tonight—May 19, Moon and Mars close together
Posted By Gary Wamsley On May 19, 2010 @ 5:21 am In Earth & Sky | Comments Disabled
Courtesy of EarthSky
A Clear Voice for Science
 This evening, the rather fat waxing crescent moon  sits fairly close to the ruddy planet Mars. Yesterday  evening, a somewhat thinner lunar crescent shone closer to the Gemini stars, Castor and Pollux. Tomorrow  evening, the first quarter moon  will shine more closely to Regulus, the brightest star in the constellation Leo the Lion.
The moon, always in motion, continually goes eastward in font of the background stars. It goes full circle (360 degrees) relative to the stars every 27 and 1/3 days. That’s about 13 degrees eastward daily. For reference, your fist held at an arm length approximates 10 degrees.
Mars, the 4th planet out from the sun, has two moons of its own. Unlike Earth’s large moon (diameter: 2160 miles), Mars’ two potato-shaped moons – Phobos and Deimos – are extremely tiny. Lengthwise, Phobos and Deimos measure about 17 miles and 10 miles, respectively.
Like Earth’s moon, these moons go eastward around their parent planet, though at a much faster pace. Phobos, the inner moon, orbits Mars in 7.6 hours, whereas Deimos, the outer moon, takes about 1.3 days. In contrast, our moon’s orbital period spans some 27.322 days.
Phobos and Deimos are little rocky worlds that may have been captured from the asteroid belt .
Written by Bruce McClure
CHANDRA Photo Album 
StarDate Online 
Sky and Telescope 
National Geographic 
Space Com 
Amazing Space 
Scope City 
Article printed from Recorder Online: http://www.berthoudrecorder.com
URL to article: http://www.berthoudrecorder.com/2010/05/19/earthsky-tonight%e2%80%94may-19-moon-and-mars-close-together/
URLs in this post:
 www.EarthSky.org: http://www.EarthSky.org
 Image: http://www.berthoudrecorder.com/wp-content/uploads/2010/05/May-20_phases.jpg
 Image: http://www.berthoudrecorder.com/wp-content/uploads/2010/05/10may19_43011.jpg
 waxing crescent moon: http://earthsky.org/tonightpost/moon-phases/waxing-crescent
 Yesterday: http://earthsky.org/es-tonight/waxing-moon-castor-pollux
 Tomorrow: http://earthsky.org/es-tonight/first-quarter-moon-or-half-moon-near-regulus-and-mars
 first quarter moon: http://earthsky.org/tonightpost/moon-phases/first-quarter
 asteroid belt: http://kids.nineplanets.org/asteroid.htm
 Astronomy Picture of the Day from NASA/JPL: http://antwrp.gsfc.nasa.gov/apod/
 CHANDRA Photo Album: http://chandra.harvard.edu/photo/
 U.S. Naval Observator Astronomical Information cente: http://www.usno.navy.mil/USNO/astronomical-applications/astronomical-information-center/astronomical-information-center
 StarDate Online: http://stardate.org/
 Sky and Telescope: http://www.skyandtelescope.com/observing/ataglance/
 National Geographic: http://news.nationalgeographic.com/news/
 Space Com: http://www.space.com/nightsky/
 Amazing Space: http://amazing-space.stsci.edu/tonights_sky/
 The York County Astronomical Society: http://www.ycas.org/tonights_sky.htm
 Scope City: http://www.scopecity.net/
Copyright © 2010 Berthoud Recorder. All rights reserved.