A Sundial that Shows Solstice
21.06.2017

What day is it? If the day -- and time -- are right, this sundial will tell you: SOLSTICE. Only then will our Sun be located just right for sunlight to stream through openings and spell out the term for the longest and shortest days of the year. But this will happen today (and again in December).

Starlight Reflections
14.04.1998

Wisps of dust fill the space between the stars. This dust is usually invisible, subtly acting to dim the light of more distant stars. Sometimes this dust is thick and prominent as dark patches on otherwise bright emission nebulae. Other times this dust may show itself by reflecting the light of bright, nearby stars.

Orion: The Big Picture
1.12.1997

Orion is big. Some of the stars that form the constellation of Orion are part of a giant gas cloud complex that stretches over 100 light years and appears more than 50 times the diameter of the Moon.

M104: The Sombrero Galaxy
15.08.1999

What's going on in the center of this spiral galaxy? Named the Sombrero Galaxy for its hat-like resemblance, M104 features a prominent dust lane and a bright halo of stars and globular clusters.

Skylab Over Earth
30.08.1995

Skylab was an orbiting laboratory launched by a Saturn V rocket in May 1973. Skylab was visited three times by NASA astronauts who sometimes stayed as long as two and a half months. Many scientific tests were preformed on Skylab, including astronomical observations in ultraviolet and X-ray light.

A Sun Pillar
30.12.2002

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.

Nearby Spiral M33
14.12.2004

Spiral galaxy M33 is a mid-sized member of our Local Group of Galaxies. M33 is also called the Triangulum Galaxy for the constellation in which it resides. About four times smaller (in radius) than...

Dawn s Endeavour
27.02.2010

On February 21st, the Space Shuttle Endeavour and the International Space Station (ISS) flew through the sky near dawn over Whitby, Ontario, Canada. Along with star trails, both were captured in this single time exposure. Glinting in sunlight 350 kilometers above the Earth, Endeavour slightly preceeded the ISS arcing over the horizon.

Auroras Over Both Earth Poles
14.11.2001

Auroras in the north and south can be nearly mirror images of each other. Such mirroring had been suspected for centuries but dramatically confirmed only last month by detailed images from NASA's orbiting Polar spacecraft.

Along the Milky Way
3.07.2021

You can't walk along the Milky Way. Still, under a dark sky you can explore it. To the eye the pale luminous trail of light arcing through the sky on a dark, moonless night does appear to be a path through the heavens.