APOD: 2025 September 9 Б Up from the Earth: Gigantic Jet Lightning
8.09.2025

What's that rising up from the Earth? When circling the Earth on the International Space Station early in July, astronaut Nicole Ayers saw an unusual type of lightning rising up from the Earth: a gigantic jet. The powerful jet appears near the center of the featured image in red, white, and blue.

Jagged Hills on Jupiters Callisto
28.08.2001

Why does Jupiter's moon Callisto have unusual jagged hills? This mystery came to light after the robot spacecraft Galileo, in orbit around Jupiter since 1995, swooped past the dark moon in May. The resulting pictures were the highest resolution yet obtained for a Jovian moon: objects as small as 3 meters across are discernable.

The Clouds of Jupiter
20.09.1997

What makes the colors in Jupiter's clouds? With a mean temperature of 120 degrees Kelvin (-153 degrees Celsius) and a composition dominated by hydrogen (about 90%), and helium (about 10%) with a smattering...

Mars Opposition
26.07.2018

Look opposite the Sun in the sky tonight and you'll see Mars at its brightest. Also within days of its closest approach Mars rises at sunset, near its brightest and best for telescopic observers too, except for the dust storm still blanketing the Red Planet.

BATSE's Biggest Gamma Ray Burst (Yet)
1.10.1996

Something big exploded but astronomers have no idea what. On September 24^th, the Burst and Transient Source Experiment (BATSE) onboard the orbiting Compton Gamma Ray Observatory recorded the most intense gamma ray burst in its five year history.

IC 4603: Reflection Nebula in Ophiuchius
21.07.2003

Why does this starfield photograph resemble an impressionistic painting? The effect is created not by digital trickery but by large amounts of interstellar dust. Dust, minute globs rich in carbon and similar in size to cigarette smoke, frequently starts in the outer atmospheres of large, cool, young stars.

Reflections on NGC 6188
25.08.1999

NGC 6188 is an interstellar carnival of young blue stars, hot red gas, and cool dark dust. Located 4000 light years away in the disk of our Galaxy, NGC 6188 is home to the Ara OB1 association, a group of bright young stars whose nucleus forms the open cluster NGC 6193.

Twelve Lunar Eclipses
28.02.2008

Welcome to the extra day in the Gregorian Calendar's leap year 2008! To celebrate, consider this grid of lunar eclipse pictures - starting in leap year 1996 and ending with February's eclipse - with the date in numerical year/month/day format beneath each image.

Home from Above
14.11.2010

There's no place like home. Peering out of the windows of the International Space Station (ISS), astronaut Tracy Caldwell Dyson takes in the planet on which we were all born, and to which she would soon return.

Corona from Svalbard
30.03.2015

During a total solar eclipse, the Sun's extensive outer atmosphere, or corona, is an inspirational sight. Streamers and shimmering features that engage the eye span a brightness range of over 10,000 to 1, making them notoriously difficult to capture in a single photograph.