Southwest Mercury
15.02.2003

The planet Mercury resembles a moon. Mercury's old surface is heavily cratered like many moons. Mercury is larger than most moons but smaller than Jupiter's moon Ganymede and Saturn's moon Titan. Mercury is much denser and more massive than any moon, though, because it is made mostly of iron.

Mars Simulated View
16.07.2003

When earthdweller Patrick Vantuyne wondered what his home planet's single large moon would look like if viewed from Mars on July 17, he availed himself of the JPL Solar System Simulator. Of course...

Orion's Horsehead Nebula
25.10.1997

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the black indentation to the red emission nebula seen just to the right of center of the above photograph. The bright star near the center is located in the belt of the familiar constellation of Orion.

Hawaii
25.07.1998

Aloha! With the graceful arc of the Earth's limb in the background, the Hawaiian Island archipelago is visible in this stunning photo taken by the astronauts onboard the shuttle Discovery in October of 1988. Along with popular beaches and tropical resorts, these volcanic islands offer extreme elevations with dark, dry, cloudless skies.

October Mars
28.10.2005

This October, Mars has become a bright, yellowish star in planet Earth's sky as it approaches oppositon, the period when Mars and Earth pass close as they orbit the Sun. How close is Mars? A mere 70 million kilometers or so, close enough to allow Earth-bound astronomers excellent views of the alluring Red Planet.

Unexpected Comet Pojmanski Now Visible
5.03.2006

Have you ever seen a comet? Comets bright enough to be visible to the unaided eye appear only every few years. Right now, however, a new comet has brightened unexpectedly and is visible as a faint streak to the unaided northern observer in the eastern morning sky just before sunrise. Binoculars may help.

Comet Meets Ring Nebula: Part II
12.05.2006

Moving rapidly through planet Earth's night sky, Fragment C of crumbling comet 73P/Schwassmann-Wachmann 3 passed almost directly in front of M57 - the Ring Nebula, and faint spiral galaxy IC 1296 on May 8.

NGC 1579: Trifid of the North
25.05.2006

Colorful NGC 1579 resembles the better known Trifid Nebula, but lies much farther north in planet Earth's sky, in the heroic constellation Perseus. About 2,100 light-years away and 3 light-years across, NGC 1579 is a captivating study in color.

A Network of Microlensing Caustics
24.08.1999

A virtual sky map like this would be of interest to astronomers studying gravitational microlensing. In microlensing, the gravity of stars near the line of sight can act to magnify the light of background objects such as distant stars, or quasars. Nowhere is this magnification greater than near a gravitational lensing caustic.

NGC 1579: Trifid of the North
29.01.2009

Colorful NGC 1579 resembles the better known Trifid Nebula, but lies much farther north in planet Earth's sky, in the heroic constellation Perseus. About 2,100 light-years away and 3 light-years across...