Mercury: A Cratered Inferno
2.01.1999

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

APOD: 2025 July 2 Б Milky Way Through Otago Spires
2.07.2025

Does the Milky Way always rise between these two rocks? No. Capturing this stunning alignment took careful planning: being in the right place at the right time. In the featured image taken in June...

September Sky
29.09.2000

Star clusters, planets, and a red giant posed for this portrait of the night sky from rural Jasper County, Iowa, USA. Astrophotographer Stan Richard recorded the four minute time exposure looking east around midnight on September 3rd at Ashton-Wildwood Park.

A Mysterious Hexagonal Cloud System on Saturn
3.04.2007

Why would clouds form a hexagon on Saturn? Nobody is yet sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.

Mercury: A Cratered Inferno
12.09.2004

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

Saturns Hexagon and Rings
20.02.2013

Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.

Red Spot Jr
18.03.2006

Jupiter's Great Red Spot, is a swirling storm seen for over 300 years, since the begining of telescopic observations of the Solar System's ruling gas giant. But over the last month it has been joined by Red Spot Jr.

The Far Side
14.09.1995

This historic picture was humanity's first glimpse of the far side of the Moon. It was taken by the Soviet spacecraft Luna 3 in October of 1959. Luna 3 followed closely...

Sunspots and Solar Active Regions
1.08.2002

July was a good month for sunspots ... really big sunspots. In fact, the full disk and inset pictures above show three large groups of spots, photographed only a few days ago on July 28. Together the sunspots span a region about thirty times the diameter of planet Earth.

In Ganymede s Shadow
7.10.2022

At opposition, opposite the Sun in Earth's sky, late last month Jupiter is also approaching perihelion, the closest point to the Sun in its elliptical orbit, early next year. That makes Jupiter exceptionally close to our fair planet, currently resulting in excellent views of the Solar System's ruling gas giant.