Red Aurora Over Australia
29.01.2017

Why would the sky glow red? Aurora. A solar storm in 2012, emanating mostly from active sunspot region 1402, showered particles on the Earth that excited oxygen atoms high in the Earth's atmosphere. As the excited element's electrons fell back to their ground state, they emitted a red glow.

Comet Leonard from Space
15.12.2021

What does Comet Leonard look like from space? Today's featured image from Origin.Space's Yangwang-1 space telescope shows not only the currently bright comet -- but several other space delights as well. Taken...

Dark Dunes on Mars
20.07.2016

How does wind affect sand on Mars? To help find out if it differs significantly from Earth, the robotic Curiosity rover on Mars was directed to investigate the dark Namib Dune in the Bagnold Dune Field in Gale Crater. Namib is the first active sand dune investigated up close outside of planet Earth.

The Moon During a Total Lunar Eclipse
25.05.2021

How does the Moon's appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse.

Dark Sky, Bright Sun
14.02.1999

In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced this dramatic...

The First Lunar Observatory
11.11.2000

The first, and so far only, lunar astronomical observatory was deployed by the Apollo 16 crew in 1972. The Far Ultraviolet Camera / Spectrograph used a 3-inch diameter Schmidt telescope to photograph the Earth, nebulae, star clusters, and the Large Magellanic Cloud.

Bright Venus
8.03.2001

Have you seen a bright evening star in the western sky lately? That's no star, that's planet Venus the second "rock" from the Sun. Blazing at -4.6 magnitude, Venus, after the Sun and Moon, is the third brightest celestial body in planet Earth's sky.

CMB Dipole: Speeding Through the Universe
15.06.2014

Our Earth is not at rest. The Earth moves around the Sun. The Sun orbits the center of the Milky Way Galaxy. The Milky Way Galaxy orbits in the Local Group of Galaxies. The Local Group falls toward the Virgo Cluster of Galaxies.

Perseverance Sol 354
25.02.2022

This Navcam mosaic from Perseverance looks out over the car-sized rover's deck, across the floor of Jezero crater on Mars. Frames used to construct the mosaic view were captured on mission sol 354. That corresponds to Earth calendar date February 17, 2022, nearly one Earth year after the rover's landing.

Julius Caesar and Leap Days
29.02.2020

In 46 BC Julius Caesar reformed the calendar system. Based on advice by astronomer Sosigenes of Alexandria, the Julian calendar included one leap day every four years to account for the fact that an Earth year is slightly more than 365 days long.