Mercury Crosses a Quiet Sun
2.12.2019

What's that black dot crossing the Sun? The planet Mercury. Mercury usually passes over or under the Sun, as seen from Earth, but last month the Solar System's innermost planet appeared to go just about straight across the middle.

Tail Wags of Comet Ikeya Zhang
15.05.2002

As Comet Ikeya-Zhang approached the Sun two months ago, it developed a complex blue ion tail. The tail was composed of ions that boiled off the nucleus and were pushed away from the Sun by the out-flowing fast-moving particles of the solar wind.

Pluto in True Color
19.03.2001

Pluto is mostly brown. The above picture captures the true colors of Pluto as well as the highest surface resolution so far recovered. No spacecraft has yet visited this most distant planet in our Solar System.

Golden Comet Holmes
3.11.2007

Surprising Comet Holmes remains easily visible as a round, fuzzy cloud in the northern constellation Perseus. Skywatchers with telescopes, binoculars, or those that just decide to look up can enjoy the solar system's latest prodigy as it glides about 150 million kilometers from Earth, beyond the orbit of Mars.

Jupiter s Swimming Storm
10.09.2020

A bright storm head with a long turbulent wake swims across Jupiter in these sharp telescopic images of the Solar System's ruling gas giant. Captured on August 26, 28, and September 1 (left to right) the storm approximately doubles in length during that period.

Venus and Mars: Passing in the Night
29.03.2022

When two planets pass on the night sky, they can usually be seen near each other for a week or more. In the case of this planetary conjunction, Venus and Mars passed within 4 degrees of each other earlier this month.

Comet ISON Approaches
7.10.2013

How impressive will Comet ISON become? No one is sure, but unfortunately, as the comet approaches the inner Solar System, it is brightening more slowly than many early predictions. Pictured above, Comet ISON is seen about two weeks ago as it continued to develop a tail.

The Largest Rock Known
2.01.2000

There, that faint dot in the center - that's the largest rock known. It is larger than every known asteroid, moon, and comet nucleus. It is larger than any other rocky planet. (Nobody knows...

Deimos: A Small Martian Moon
15.11.1998

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 9 miles across.

Planets Around Sun-Like Stars
31.01.1996

Do many Sun-like stars have planets? Speculation on this point has been ongoing since humanity's realization that other stars existed. Only in the past year, however, have answers and discoveries been realized. The above plot summarizes the four known cases of normal stars having planets.