Moonrise and Mountain Shadow
13.03.2020

What phase of the Moon is 3.14 radians from the Sun? The Full Moon, of course. Even though the Moon might look full for several days, the Moon is truly at its full phase when it is 3.14 radians (aka 180 degrees) from the Sun in ecliptic longitude.

Full Flower Moonrise
8.05.2020

Rising as the Sun set, the Moon was bright and full in planet Earth skies on May 7 and known to some as a Flower Moon. Near the horizon it does seem to take on rose pink hues of reddened sunlight in this reflective twilight scene.

Moon Setting Behind Teide Volcano
21.03.2020

These people are not in danger. What is coming down from the left is just the Moon, far in the distance. Luna appears so large here because she is being photographed through a telescopic lens.

Morning, Planets, Moon, and Montreal
19.03.2020

Dawn's early light came to Montreal, northern planet Earth, on March 18, the day before the vernal equinox. At the end of that nearly equal night the Moon stands above a dense constellation of urban lights in this serene city and skyscape. Of course the Moon's waning crescent faces toward the rising Sun.

Biking to the Moon
1.10.2020

As you watched October's first Full Moon rise last night, the Full Moon closest to the northern autumnal equinox, you were probably asking yourself, "How long would it take to bike...

Mare Frigoris
7.10.2020

Lighter than typically dark, smooth, mare the Mare Frigoris lies in the far lunar north. Also known as the Sea of Cold, it stretches across the familiar lunar nearside in this close up of the waxing gibbous Moon's north polar region. Dark-floored, 95 kilometer wide crater Plato is just left of the center.

Deimos: A Small Martian Moon
2.09.2001

Mars has two tiny moons, Phobos and Deimos. Pictured above is Deimos, the smaller moon of Mars. In fact, Deimos is one of the smallest known moons in the Solar System measuring only nine miles across.

Colors of the Moon
10.11.2020

What color is the Moon? It depends on the night. Outside of the Earth's atmosphere, the dark Moon, which shines by reflected sunlight, appears a magnificently brown-tinged gray. Viewed from inside the Earth's atmosphere, though, the moon can appear quite different.

APOD: 2020 August 13 Б Jupiter and Saturn Rising Beyond Alien Throne Rock
12.08.2020

Whatбplanets are those behind that unusualбrock spire? Saturn (lower left) and Jupiter.б This month, after sunset, the bright planetary duo are quite prominent toward the southeast.б Now your view of our Solar...

Great Conjunction over Sicilian Lighthouse
7.12.2020

DonБt miss the coming great conjunction. In just under two weeks, the two largest planets in our Solar System will angularly pass so close together in Earth's sky that the Moon would easily be able to cover them both simultaneously. This pending planetary passage -- on December 21 -- will be the closest since 1623.