Morning, Planets, Moon, and Montreal
20.03.2020

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.

Moon, Mars, Saturn, Jupiter, Milk Way
20.05.2020

It is not a coincidence that planets line up. That's because all of the planets orbit the Sun in (nearly) a single sheet called the plane of the ecliptic. When viewed from inside that plane -- as Earth dwellers are likely to do -- the planets all appear confined to a single band.

Biking to the Moon
2.10.2020

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
8.10.2020

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.

Planetary Alignment over Italy
19.12.2021

It is not a coincidence that planets line up. That's because all of the planets orbit the Sun in (nearly) a single sheet called the plane of the ecliptic. When viewed from inside that plane -- as Earth dwellers are likely to do -- the planets all appear confined to a single band.

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
11.11.2020

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.

The Full Moon of 2021
1.01.2022

Every Full Moon of 2021 shines in this year-spanning astrophoto project, a composite portrait of the familiar lunar nearside at each brightest lunar phase. Arranged by moonth, the year progresses in stripes beginning at the top.

A Moon Dressed Like Saturn
2.08.2022

Why does Saturn appear so big? It doesn't -- what is pictured are foreground clouds on Earth crossing in front of the Moon. The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight known as ashen glow.

Find the New Moon
25.07.2022

Can you find the Moon? This usually simple task can be quite difficult. Even though the Moon is above your horizon half of the time, its phase can be anything from crescent to full.