Planets In The Sun
5.05.2000

Today, all five naked-eye planets (Mercury, Venus, Mars, Jupiter, Saturn) plus the Moon and the Sun will at least approximately line-up. As viewed from planet Earth, they will be clustered within about 26 degrees, the closest alignment for all these celestial bodies since February 1962, when there was a solar eclipse!

Worlds of a Distant Sun: 47 Ursae Majoris b
5.10.1997

In the last few years, observational astronomy has given humanity evidence of the existence of worlds beyond the solar system. Solar-type stars are now inferred to harbor planets of approximately Jupiter mass - some residing in temperature zones which could conceivably support liquid water and therefore life!

The 47 Ursae Majoris System
17.08.2001

Watching and waiting, astronomers have uncovered the presence of more than 70 planets orbiting stars other than the Sun. So far almost all these extrasolar planets have crazy elongated orbits, lie uncomfortably close to their parent stars, or are found in bizarre, inhospitable systems.

Moon, Planets, and Rocket Trails
14.07.1999

Are you an early riser? Over the last month or so, the bright planets Jupiter and Saturn have come to adorn eastern skies before sunrise. In fact, astrophotographer Joe Orman anticipated that an early...

Pluto: The Frozen Planet
28.12.1997

The Hubble Space Telescope imaged Pluto and its moon Charon in 1994. Pluto is usually the most distant planet from the Sun but because of its elliptic orbit Pluto crossed inside of Neptune's orbit in 1979 and will cross back out again in 1999.

Pluto and Charon Eclipse a Triple Star
11.09.2002

Occasionally, a planet in our Solar System will pass in front of a bright star. Since stars and planets take up so little space on the sky, such events are quite rare. Two months ago, however, Pluto and its large moon Charon passed in front of a comparatively bright triple star system known as P126.

Pluto: The Frozen Planet
13.02.1999

This portrait of Pluto and its companion Charon was taken by the Hubble Space Telescope in 1994. Pluto is usually the most distant planet from the Sun but because of its eccentric orbit Pluto crossed inside of Neptune's orbit in 1979.

51 Pegasi: A New Planet Discovered
1.12.1995

Are we alone in the universe? Do other stars have planets too? Humanity took one step closer to answering these questions in October 1995 when it was announced that the star 51 Pegasi harbors at least one planet.

UB313: Larger than Pluto
7.02.2006

What do you call an outer Solar System object that is larger than Pluto? Nobody is yet sure. The question arose recently when 2003 UB313, an object currently twice as far out as Pluto and not in the plane with the rest of the planets, was verified recently to be 30 percent wider than Pluto.

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.