Retrograde Mars
11.05.2008

Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun.

A Waterspout in Florida
17.07.2013

What's happening over the water? Pictured above is one of the better images yet recorded of a waterspout, a type of tornado that occurs over water. Waterspouts are spinning columns of rising moist air that typically form over warm water.

Equinox Earth
28.09.2013

From a geostationary orbit 36,000 kilometers above the equator, Russian meteorological satellite Elektro-L takes high-resolution images our fair planet every 30 minutes. But only twice a year, during an Equinox, can it capture an image like this one, showing an entire hemisphere bathed in sunlight.

M31: The Andromeda Galaxy
30.07.2014

Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it.

APOD: 2020 August 15 Б Mars at the Moons Edge
15.08.2020

Does the Moon ever block out Mars? Yes, the Moon occasionally moves in front of all of the Solar System's planets. Just this past Sunday, as visible from some locations in South America, a waning gibbous Moon eclipsed Mars.

Night Sky Reflected
13.09.2021

What's that in the mirror? In the featured image of the dark southern sky, the three brightest galaxies of the night are all relatively easy to identify. Starting from the left, these are the Small Magellanic Cloud (SMC), the Large Magellanic Cloud (LMC), and part of the central band of our Milky Way Galaxy.

The Galactic Core in Infrared
17.01.2015

What's happening at the center of our Milky Way Galaxy? To help find out, the orbiting Hubble and Spitzer space telescopes have combined their efforts to survey the region in unprecedented detail in infrared light. Milky Way's center because visible light is more greatly obscured by dust.

The Long Shadow of the Moon
27.11.2003

The long shadow of the Moon fell across the continent of Antarctica on November 23rd, during the second total solar eclipse of 2003. In this view from orbit, based on data from the MODIS instrument on board the Earth observing Aqua satellite, the Moon's shadow stretches for almost 500 kilometers.

The NTT SUSI Deep Field
15.09.1998

What happens if you point a large telescope at nothing? The above New Technology Telescope SUSI Deep Field photograph isolated a small patch of sky picked to contain no bright objects at all.

Old Faithful Below a Yellowstone Sky
7.08.2007

You don't have to be at Yellowstone to see a sky this beautiful, but it helps. Only at Yellowstone National Park in Wyoming, USA, would you see the picturesque foreground of the famous Old Faithful Geyser erupting in front an already picturesque sky.