APOD: 2026 February 16 Б Unexplained Shocks Around a White Dwarf Star
16.02.2026

How is RXJ0528+2838 creating such shock waves? A recently discovered white dwarf star, the farther left of the two largest white spots, RXJ0528+2838, was found 730 light-years away from Earth. Most stars...

Inside Mars
23.03.2000

What's inside Mars? From orbit, the Mars Global Surveyor (MGS) spacecraft has recorded detailed images of the red planet since July 1997. Still, its cameras can not look beneath the surface. But minute...

Dust and the Helix Nebula
31.12.2009

Dust makes this cosmic eye look red. The eerie Spitzer Space Telescope image shows infrared radiation from the well-studied Helix Nebula (NGC 7293) a mere 700 light-years away in the constellation Aquarius.

Water Ice Detected Beneath Moons Surface
25.10.2010

Is there enough water on the moon to sustain future astronauts? The question has important implications if humanity hopes to use the Moon as a future outpost. Last year, to help find out, scientists crashed the moon-orbiting LCROSS spacecraft into a permanently shadowed crater near the Moon's South Pole.

Comet and CME on the Sun
5.10.2011

Did a sun-diving comet just cause a solar explosion? Probably not. This past weekend a comet dove toward the Sun and was followed very quickly by a Coronal Mass Ejection (CMEs) from the other side of the Sun.

MESSENGER s First Day
8.10.2011

One solar day on a planet is the length of time from noon to noon. A solar day lasts 24 hours on planet Earth. On Mercury a solar day is about 176 Earth days long.

Cosmic Rays at Voyager 1
8.09.2012

Launched on a grand tour of the outer planets in 1977, by good fortune the twin Voyager spacecraft were also headed in the general direction of the Sun's motion relative to nearby stars. Thirty five years later, Voyager 1 appears to be nearing the boundary of the Sun's heliosphere and interstellar space.

The Map of Dione
6.11.2014

This cylindrical projection global map is one of six new color maps of Saturn's midsized icy moons, constructed using 10 years of image data from the Cassini spacecraft. Discovered by Cassini (the astronomer) in 1684, Dione is about 1,120 kilometers across.

Equinox on a Spinning Earth
19.03.2017

When does the line between day and night become vertical? Tomorrow. Tomorrow is an equinox on planet Earth, a time of year when day and night are most nearly equal. At an equinox, the Earth's terminator -- the dividing line between day and night -- becomes vertical and connects the north and south poles.

Young Star Cluster Trumpler 14 from Hubble
14.05.2019

Why does star cluster Trumpler 14 have so many bright stars? Because it is so young. Many cluster stars have formed only in the past 5 million years and are so hot they emit detectable X-rays.