Crescent Moon and Venus
6.03.2009

Last Friday, the Moon and Venus shared the early evening sky in a beautiful conjunction. Separated by only about 2 degrees, they also were both in a crescent phase. Just like our Moon, Venus can appear as a full disk or a thin crescent.

A Sun Pillar Over Maine
2.01.2006

Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. Ice sometimes forms flat, stop-sign shaped crystals as it falls from high-level clouds.

Sunlight Through Saturn's Rings
11.05.1996

Normally, Earth based astronomers view Saturn's spectacular ring system fully illuminated by reflected sunlight. However, this November 1995 Hubble Space Telescope composite image was made to take advantage of an unusual perspective, with the Sun actually illuminating the rings from below.

Stars Over Easter Island
12.10.2009

Why were the statues on Easter Island built? No one is sure. What is sure is that over 800 large stone statues exist there. The Easter Island statues, stand, on the average, over twice as tall as a person and have over 200 times as much mass.

The Firework Nebula
4.07.1995

The Firework Nebula, known to astronomers as "GK Per", is the result of a type of stellar explosion called a nova. In a nova, a very compact star called a white dwarf blasts away gas that had accumulated on its surface.

Impact on Jupiter
28.07.1998

In 1993, a strange string of comet pieces was discovered near the planet Jupiter. So unusual a sight, Comet Shoemaker-Levy 9 (SL9) quickly became the object of much scientific curiosity. Studies showed that the Sun would soon perturb the orbit of SL9 so that it would actually

A Mars Glint
8.06.1998

If aligned just right, even a planet can produce a glint. The above combined pictures of Mars make the red planet appear unusually elongated - Mars is really almost spherical. However, these pictures were taken when the Sun was nearly directly behind the Mars Global Surveyor (MGS) spacecraft.

Lasers in Eta Carinae
11.01.1996

Have you heard about the great LASER light show in the sky? Well, nobody had until it was announced just yesterday by a team led by K. Davidson (U. Minnesota) and S. Johansson (U. Lund).

Northern Summer Twilight
19.06.2021

Nights grow shorter and days grow longer as the summer solstice approaches in the north. Usually seen at high latitudes in summer months, noctilucent or night shining clouds begin to make their appearance. Drifting...

Terkezi Oasis in the Sahara Desert
12.11.2002

Dominating the top third of Africa is the largest band of dry land on Earth: the Sahara Desert. Stretching across the Sahara are vast planes of sand and gravel, seas of sand dunes, and barren rocky mountains.