Unknown Dark Material on Mercury
6.07.2009

What is that strange material on Mercury? When flying by Mercury last October, the robotic MESSENGER spacecraft imaged much of the solar system's innermost planet in unprecedented detail. As common in science, new data bring new mysteries.

A Superior Conjunction Of Mercury
8.09.1999

In astronomical parlance, an interior planet is at superior conjunction when it is located on the opposite side of the Sun from Earth. Mercury, the solar system's innermost planet, zips past this point in its orbit today.

Mercury And The Moon
11.11.1999

Mercury is the closest planet to the Sun and never moves far from our parent star in Earth's sky. Racing around its tight orbit, this well-done world is a little over 1/3 the diameter of Earth and is often lost to our view in the solar glare.

Mercury Astronauts and a Redstone
6.04.1997

Space suited project Mercury astronauts John H. Glenn, Virgil I. Grissom, and Alan B. Shepard Jr. (left to right) are pictured here posing in front of a Redstone rocket in this vintage 1961 NASA publicity photo. Project Mercury was the first U.S. program designed to put humans in space.

Mercurys Transit: An Unusual Spot on the Sun
14.11.2006

What's that dot on the Sun? If you look closely, it is almost perfectly round. The dot is the result of an unusual type of solar eclipse that occurred last week. Usually it is the Earth's Moon that eclipses the Sun.

Planets in the West
24.06.2005

This weekend three planets will grace the western sky, forming a lovely trio easily visible shortly after sunset. Saturday evening in particular will find Saturn, Venus, and Mercury all within a 2 degree circle (about the size of your thumb held at arm's length) above the western horizon.

Mercury Astronauts and a Redstone
18.09.1999

Space suited project Mercury astronauts John H. Glenn, Virgil I. Grissom, and Alan B. Shepard Jr. (left to right) are posing in front of a Redstone rocket in this vintage 1961 NASA publicity photo. Project Mercury was the first U.S. program designed to put humans in space.

Mercury Astronauts and a Redstone
4.04.1998

Space suited project Mercury astronauts John H. Glenn, Virgil I. Grissom, and Alan B. Shepard Jr. (left to right) are posing in front of a Redstone rocket in this vintage 1961 NASA publicity photo. Project Mercury was the first U.S. program designed to put humans in space.

Mercury Astronauts and a Redstone
7.01.1996

Space suited project Mercury astronauts John H. Glenn, Virgil I. Grissom, and Alan B. Shepard Jr. (left to right) are pictured here posing in front of a Redstone rocket in this 1961 NASA publicity photo. Project Mercury was the first U.S. program designed to put humans in space.

Sky and Planets
10.03.2000

On February 10th, an evocative evening sky above Rocklin, California, USA inspired astrophotographer Steve Sumner to record this remarkable sight - five planets and the Moon. Near its first quarter phase, the bright Moon...