HI4PI: The Hydrogen Sky
24.10.2016

Where are the Milky Way's gas clouds and where are they going? To help answer this question, a new highest-resolution map of the sky in the universe's most abundant gas -- hydrogen -- has been completed and recently released, along with its underlying data.

X-Ray Wind From NGC 3783
1.06.2000

A black hole is supposed to inexorably attract matter. But the intense radiation generated as material swirls and plunges into its high gravity field also heats up surrounding gas and drives it away.

A Scorpius Sky Spectacular
7.04.2019

If Scorpius looked this good to the unaided eye, humans might remember it better. Scorpius more typically appears as a few bright stars in a well-known but rarely pointed out zodiacal constellation. To get a spectacular image like this, though, one needs a good camera, color filters, and a digital image processor.

Farewell Jupiter
9.03.2003

Next stop: Saturn. The Cassini spacecraft, launched from Earth in 1997, has now swung past Jupiter and should arrive at Saturn in the year 2004. Pictured to the left is a parting shot from Cassini in January that would not have been possible from Earth: Jupiter showing a crescent phase.

A Raging Storm System on Saturn
28.04.2013

It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet.

Pink Aurora Over Crater Lake
25.07.2012

Why is this aurora strikingly pink? When photographing picturesque Crater Lake in Oregon, USA last month, the background sky lit up with auroras of unusual colors. Although much is known about the physical mechanisms that create auroras, accurately predicting the occurrence and colors of auroras remains a topic of investigation.

Two Hours Before Neptune
22.09.2002

Two hours before closest approach to Neptune in 1989, the Voyager 2 robot spacecraft snapped this picture. Clearly visible for the first time were long light-colored cirrus-type clouds floating high in Neptune's atmosphere. Shadows of these clouds can even be seen on lower cloud decks.

Impact on Europa
15.08.1997

This bull's-eye pattern marks the impact of a mountain-sized comet or asteroid on the icy surface of Jupiter's moon Europa. Recorded by the Galileo spacecraft in April of this year, the composite false color image clearly reveals the telltale concentric fractures which cover about

Good Morning Mars
19.06.1998

Looking down on the Northern Hemisphere of Mars on June 1, the Mars Global Surveyor spacecraft's wide angle camera recorded this morning image of the red planet. Mars Global Surveyor's orbit...

APOD: 2023 February 22 Б Our Increasingly Active Sun
22.02.2023

Our Sun is becoming a busy place. Only two years ago, the Sun was emerging from a solar minimum so quiet that months would go by without even a single sunspot. In contrast, already...