APOD: 2004 August 27- The Sedna Scenario
27.08.2004

The discovery of Sedna (aka 2003 VB12), the most distant known object orbiting the Sun, presents a mystery. Pluto's orbit averages about 40 AU in radius, where an AU (Astronomical Unit) is the Earth-Sun distance.

Leonids Above Torre de la Guaita
15.11.2014

Leonids Meteor Shower came to an impressive crescendo in 1999. Observers in Europe saw a sharp peak in the number of meteors visible around 0210 UTC during the early morning hours of November 18. Meteor counts then exceeded 1000 per hour - the minimum needed to define a true meteor storm.

Sputnik: Traveling Companion
3.10.1998

Sputnik means "traveling companion". Despite the innocuous sounding name, the launch of the Earth's first "artificial moon", Sputnik 1, by the Soviets on October 4, 1957 shocked the free world, setting in motion events which resulted in the creation of NASA and the race to the Moon.

A Setting Sun Trail
29.07.2002

The Sun appears to move on the sky because the Earth rotates. The extreme brightness of the Sun, however, makes it difficult to capture a sun-trail -- the path the Sun traces on the sky.

Liftoff With the Space Shuttle
23.10.2002

What would it look like to see a Space Shuttle liftoff from just above the shuttle? Because the answer has value in assessing spacecraft performance, NASA attached a small RocketCam to the side of the External Tank on the launch of the Space Shuttle Atlantis earlier this month.

Sputnik: Traveling Companion
27.04.1997

Sputnik means "traveling companion". Despite the innocuous sounding name, the launch of the Earth's first "artificial moon", Sputnik 1, by the Soviets on October 4, 1957 shocked the free world, setting in motion events which resulted in the creation of NASA and the race to the Moon.

Globular Cluster M3
19.07.1998

This huge ball of stars predates our Sun. Long before mankind evolved, before dinosaurs roamed, and even before our Earth existed, ancient globs of stars condensed and orbited a young Milky Way Galaxy.

Discovery Orbiter Anaglyph
16.09.2006

Approaching the International Space Station on STS-121 in July, the Shuttle Orbiter Discovery posed for a series of photographs. The process was part of an inspection to check for damage to the orbiter, but against the backdrop of planet Earth 300 kilometers below, the pictures themselves are stunning.

Planets and Fire by Moonlight
9.07.2008

On July 5th, wandering planets, bright stars, and a young crescent Moon graced western skies after sunset. Arrayed along the solar system's ecliptic plane, the three celestial beacons forming this skyscape's eye-catching line-up with the Moon are Saturn (upper left), then Mars, and finally Regulus, alpha star of the constellation Leo.

Teide Sky Trails
12.02.2010

The snow capped Teide volcano is reflected in a pool of water in this nearly symmetric night sky view from the Canary Island Tenerife. Bright north star Polaris stands above the peak in an exposure that also captures the brilliant trail of a polar orbiting Iridium satellite.