An Aurora Before the Storm
19.05.2000

Early April brought some of the most intense auroral storms this decade. An aurora on April 6 was reported to be the largest visible on Earth since 1989, and was seen throughout Europe and much of northern North America.

GK Per: Nova of 1901
5.11.2011

Early in the 20th century, GK Persei briefly became one of the brightest stars in planet Earth's sky, an event known as Nova Persei 1901. Documented in this modern day composite of two images from 2003 and 2011 the ejecta from the explosion, popularly called the Firework Nebula, continues to expand into space.

Coronal Rain on the Sun
26.02.2013

Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that produced both a Coronal Mass Ejection and a moderate solar flare. What was more unusual, however, was what happened next.

GRAIL Maps the Moons Gravity
19.03.2013

How did the Moon form? To help find out, NASA launched the twin Gravity Recovery and Interior Laboratory (GRAIL) satellites in 2011 to orbit and map the Moon's surface gravity in unprecedented detail.

Comet 57P Falls to Pieces
2.08.2002

Comet 57P has fallen to pieces, at least 19 of them. Orbiting the Sun every 5.9 years or so this faint comet - also christened Comet 57P/du Toit-Neujmin-Delporte for its three 1941 co-discoverers - is simply...

APOD: 2024 July 24 Б Exaggerated Moon
24.07.2024

Our Moon doesn't really have craters this big. Earth's Moon, Luna, also doesn't naturally show this spikey texture, and its colors are more subtle. But this digital creation is based on reality.

Ancient Volcanos of Mars
8.08.2002

Findings of ancient martian microbial fossils in meteorites and liquid water related features on Mars' surface are currently controversial issues. But one thing long established by space-based observations of the Red Planet is the presence of volcanos, as Mars supports some of the largest volcanos in the solar system.

Galileo's First Color Image of Io
19.07.1996

Above is the first color image of Jupiter's volcanic moon Io released by the Galileo Project. (Io sounds like "eye-oh".) The image was made on June 25 when the Galileo spacecraft approached within 1.4 million miles.

A Flight of Helios
24.07.2011

An example of solar-powered flight, NASA's Helios aircraft flew almost one hundred years after the Wright brothers' historic flight on December 17, 1903. Pictured here at 3,000 meters in in skies northwest of Kauai, Hawaii, USA in August 2001, the remotely piloted Helios is traveling at about 40 kilometers per hour.

North Star: Polaris and Surrounding Dust
28.04.2021

Why is Polaris called the North Star? First, Polaris is the nearest bright star toward the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to revolve around Polaris, but Polaris itself always stays in the same northerly direction -- making it the North Star.