The phases of the Moon are determined by the relative positions of the Moon, Earth, and Sun.
With astronomy being celebrated around the globe this month, join the fun by participating in a unique lunar observing challenge: track down 20 features once thought to show evidence of change from weather, geology, and even life.
It's easy to take high-quality images of the lunar disk.
Baptized in the fire of yesterday's total solar eclipse, a very young crescent Moon emerges into the night sky.
Like "catching some rays"? This weekend's Blue Moon invites us to explore the beauty and dazzle of crater rays, the tracks left by powerful impacts in the not-so-distant past.
Walk in the astronauts' footsteps as you explore the places they visited in the heyday of Apollo program. Use these helpful maps to start you on your way.
With the Moon riding high this week, what better time to look for its three best-known yet enigmatic "ring" craters? We welcome back the waxing Moon this week. It's a chance for many of us to put dark-sky targets on the back burner and give some love to she who lights the night. During fall, the evening Moon…
With a subtle beauty all its own, the earthshine we see glowing in the lunar night invites us to consider Earth's many connections to the Moon.
Explore the Moon with binoculars or a telescope.
The perpetuation of the supermoon myth is mostly motivated by desire for publicity. But much of what we call the supermoon is just our eyes playing tricks on us.
Learn the phase of the Moon tonight, the day you were born, or on any historical date.
As the moon wanes in the gibbous phase in the nights to come, see if you can find and observe some of 100 of Charles Wood's classic lunar hit list, including craters, basins, mountains, rilles, and domes.
We'll see a "blue Moon" next Friday, but what does that mean? From the Middle Ages to the game of Trivial Pursuit, a folklorist explores the origin of the phrase.
You can see 9% more Moon than just what's on the near side thanks to lunar libration.
Tycho is the most conspicuous crater visible near full Moon, shining brilliantly and radiating great long rays. But the rays from Tycho that partially encircle the full Moon are not distributed equally in all directions.
The crater Plato is one of the superstars for observers of the Moon. It's big, conspicuous with its dark floor ringed by a bright rim, and long a subject of speculation, and controversy.
Oblique impact resolves the mystery of one of the most bizarre crater pairs on the Moon: Messier and Messier A. Previous explanations for this crater pair ranged from imaginative to fantastical. All were wrong.
Mare Nectaris is the smallest of the circular maria on the Moon; lavas extend only 350 kilometers from shore to shore. But the Nectaris basin is beautifully defined by the spectacular Altai Scarp, which forms the southwestern rim of the basin.
Whatever its phase, the magnificent Moon has lots to offer.
The absolute best example of a lunar fault is the Straight Wall. This well-known lunar feature is a long thin line that never fails to impress; even through a small telescope it's a fascinating sight.
Is Friday's full Moon "blue"? Depends on who you ask, but if someone answers yes, it's because of a mistake in a 1946 issue of Sky & Telescope.
The full Moon is very bright, but there are still many fascinating features to observe during this or any phase when you look far from the terminator.
Here are some tips for hunting one of nature's most captivating sights.
On five consecutive mornings beginning January 29th, early morning risers have an opportunity to glimpse the Moon’s most spectacular "hidden" landform.
This mare is a challenging sight; view it July 16th to 19th and August 12th to 15th.