Sunshine, Earthshine
19.03.2015

Today's date marks an Equinox and a New Moon. Remarkably, while the exact timing of both geocentric events occur within a span of only 13 hours, the moon also reaches its new phase only 14 hours after perigee, the closest point in its orbit.

Lightning over Colorado
5.12.2016

Have you ever watched a lightning storm in awe? Join the crowd. Oddly, nobody knows exactly how lightning is produced. What is known is that charges slowly separate in some clouds causing rapid electrical discharges (lightning), but how electrical charges get separated in clouds remains a topic of much research.

Selfie at Vera Rubin Ridge
26.01.2018

On sol 1943 of its journey of exploration across the surface of Mars, the Curiosity Rover recorded this selfie at the south rim of Vera Rubin Ridge. Of course a sol is a Martian solar day, about 40 minutes longer than an Earth day. Curiosity's sol 1943 corresponds to Earth date January 23, 2018.

APOD: 2024 September 2 Б A Triangular Prominence Hovers Over the Sun
2.09.2024

Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence. Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months.

Io Rotating
24.10.2000

The surface of Io is continually changing. Jupiter's moon is the home to many powerful volcanoes so active they are effectively turning the moon inside out. The above time-lapse sequence is a composite of images taken during two space missions that approached the violent moon: Voyager and Galileo.

The Last Moon Shot
4.05.1997

In 1865 Jules Verne predicted the invention of a space capsule that could carry people. In his science fiction story "From the Earth to the Moon", he outlined his vision of a cannon in Florida so powerful that it could shoot a "Projectile-Vehicle" carrying three adventurers to the Moon.

Solstice Sun In Soft X-rays
21.12.1998

The solstice occurs today at 8:56 PM Eastern Standard Time. At the solstice the sun reaches its most southerly position in the sky and winter begins for the Northern Hemisphere while summer starts South of the Equator.

The Solar Spectrum
27.02.2005

It is still not known why the Sun's light is missing some colors. Shown above are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.

Thirteen Seconds After Impact
5.07.2005

Fireworks came early on July 4th when, at 1:52am EDT, the Deep Impact spacecraft's probe smashed into the surface of Comet Tempel 1's nucleus at ten kilometers per second. The well-targeted impactor probe was vaporized as it blasted out an expanding cloud of material, seen here 13 seconds after the collision.

Martian Chiaroscuro
29.08.2020

Deep shadows create dramatic contrasts between light and dark in this high-resolution close-up of the martian surface. Recorded on January 24, 2014 by the HiRISE camera on board the Mars Reconnaissance Orbiter, the scene spans about 1.5 kilometers.