Ganymede from Juno
14.06.2021

What does the largest moon in the Solar System look like? Jupiter's moon Ganymede, larger than even Mercury and Pluto, has an icy surface speckled with bright young craters overlying a mixture of older, darker, more cratered terrain laced with grooves and ridges.

Asteroids in the Distance
16.03.1998

Rocks from space hit Earth every day. The larger the rock, though, the less often Earth is struck. Many kilograms of space dust pitter to Earth daily. Larger bits appear initially as a bright meteor. Baseball-sized rocks and ice-balls streak through our atmosphere daily, most evaporating quickly to nothing.

A Live View from the International Space Station
2.06.2019

If you were floating above the Earth right now, this is what you might see. In 2014, a robotic SpaceX Dragon capsule that delivered supplies to the Earth-orbiting International Space Station (ISS) also delivered High Definition Earth Viewing (HDEV) cameras that take and transmit live views of Earth.

Apollo 13 Views of the Moon
3.03.2020

What if the only way to get back to Earth was to go around the far side of the Moon? Such was the dilemma of the Apollo 13 Crew in 1970 as they tried to return home in their unexpectedly damaged spacecraft.

Streak and Plume from SpaceX Crew2 Launch
24.04.2021

What's happening in the sky? The pre-dawn sky first seemed relatively serene yesterday morning over Indian Harbor Beach in Florida, USA. But then it lit up with a rocket launch. Just to the north, NASA's SpaceX Crew-2 Mission blasted into space aboard a powerful Falcon 9 rocket.

Annular Solar Eclipse over New Mexico
31.08.2016

What is this person doing? In 2012 an annular eclipse of the Sun was visible over a narrow path that crossed the northern Pacific Ocean and several western US states. In an annular solar...

Jupiters Europa from Spacecraft Galileo
27.09.2016

What mysteries might be solved by peering into this crystal ball? In this case, the ball is actually a moon of Jupiter, the crystals are ice, and the moon is not only dirty but cracked beyond repair. Nevertheless, speculation is rampant that oceans exist under Europa's fractured ice-plains that could support life.

Rainbow Airglow over the Azores
18.04.2021

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

Apollo 12: Surveyor 3 and Intrepid
8.04.1999

On April 20, 1967, NASA's robot spacecraft Surveyor 3 landed on the moon, touching down on the inside slope of a small lunar crater in the Ocean of Storms. Over 2 1/2 years...

The Potsdam Gravity Potato
14.12.2014

Why do some places on Earth have higher gravity than others? Sometimes the reason is unknown. To help better understand the Earth's surface, sensitive measurments by the orbiting satellites GRACE and CHAMP were used to create a map of Earth's gravitational field.