Orbits of Potentially Hazardous Asteroids
29.08.2021

Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth.

Flying Past Pluto
6.10.2015

What would it look like to fly past Pluto? The robotic New Horizons spacecraft did just this in late July and continues to return stunning pictures of the dwarf planet. Some well-chosen flyby images have now been digitally sequenced to create the featured video.

Total Solar Eclipse Shadow from a Balloon
27.08.2018

Where were you during the Great American Eclipse of 2017? A year ago last week, over 100 million of people in North America went outside to see a partial eclipse of the Sun, while...

Colors of the Moon
15.05.2022

What color is the Moon? It depends on the night. Outside of the Earth's atmosphere, the dark Moon, which shines by reflected sunlight, appears a magnificently brown-tinged gray. Viewed from inside the Earth's atmosphere, though, the moon can appear quite different.

Cassini Spacecraft Crosses Saturn's Ring Plane
15.02.2010

If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear.

Venus South Polar Vortex
28.09.2010

What's happening over the South Pole of Venus? To find out, scientists have been studying images taken by the robotic Venus Express spacecraft when it passes over the lower spin axis of Earth's overheated twin.

The Supernova and Cepheids of Spiral Galaxy UGC 9391
6.06.2016

What can this galaxy tell us about the expansion rate of the universe? Perhaps a lot because UGC 9391, featured, not only contains Cepheid variable stars (red circles) but also a recent Type Ia supernova (blue X).

Manhattanhenge: A New York Sunset
13.07.2007

Today, if it is clear, well placed New Yorkers can go outside at sunset and watch their city act like a modern version of Stonehenge. Manhattan will flood dramatically with sunlight just as the Sun sets precisely on the centerline of every street.

Flying Over the Columbia Hills of Mars
19.05.2008

What it would be like to fly over Mars? Combining terrain data from the orbiting Mars Global Surveyor spacecraft (now dormant) with information about the robotic Spirit rover currently rolling across Mars has resulted in a digital movie that shows what a flight over the Columbia Hills might look like.

Galaxy Group Hickson 31
22.02.2010

Will the result of these galactic collisions be one big elliptical galaxy? Quite possibly, but not for another billion years. Pictured above, several of the dwarf galaxies of in the Hickson Compact Group 31 are seen slowly merging.