Many stargazers enjoy the challengeof spotting the moon inthe evening twilight sky as soon aspossible after its dark new moon phase. Butthis month, moon lovers should rise at dawn instead, and search for the"oldmoon" just before it passes into the sun's glare and is not visible atall.
August is not a good month to huntfor the moon just afterits new moon phase. Just after the sun sets, the ecliptic is at a veryshallowangle to the horizon, so the moon is very low. This makes the moon veryhard tospot in the glow of twilight. During new moon, the moon is at a pointin itsorbit where it is between the Earth and the sun. Because of themechanics ofthe moon, at this time it usually rises and sets with the sun. [More: HowMoonPhases Work]
This graphicshows where to look to spot the moonbefore it hits new moon at 11:09 p.m. Eastern Daylight Time on Monday,Aug. 9.
The only time you can see the moonexactly at new moon ison the rare occasions when there is a solar eclipse, and the moon isvisible ?with no detail ? as a dark object blocking the sun. But because themoon'sorbit is tilted slightly with respect to the orbit of Earth around thesun,this only happens when the paths come into certainalignment. The most recent totalsolar eclipse occurred on July 11.
At other new moons, the moon passesabove or below thesun, and it is hidden from our view by the overwhelming glare of thesun.
The morning before the date of newmoon, Sunday Aug. 8, itshould be possible to catch a last glimpse of the "old moon" in thepre-dawn sky. The slender crescent moon will rise a little after 4 a.m.localtime, about two hours before sunrise at 6 a.m. The exact times willvarydepending on where you are located in your time zone.
Observing the eastern sky justbefore dawn also gives youthe jump on the season. The slim crescent moon will be surrounded bythe brilliantstars of winter, a full six months before they come to dominate ourwinterevening sky. This is because of the rotation of the Earth and itsorbitalmotion around the sun.
Just above and to the left of themoon are the famoustwins, Castor and Pollux, in the constellation Gemini. To the right ofthe moonis Orion with its pair of first magnitude stars, red Betelgeuse andwhiteRigel, along with Orion's Belt and Sword. Higher in the sky will bebrilliantCapella in Auriga and glowing red Aldebaran in Taurus. The latter issurroundedby the Hyades star cluster, while the more famous Pleiades star clusterrideshigher still.
All in all, a summer treat, seeinga rarephase of the moon and the "winter" sky in warm temperaturesfor achange. Worth getting up early to see.
- Gallery? Amazing Moon Photos
- Telescopesfor Beginners
- More Night SkyFeatures from Starry Night Education
Thisarticle was provided to SPACE.com by Starry NightEducation, theleader in space science curriculum solutions.
