APOD: 2025 July 7 Б Interstellar Comet 3I ATLAS
7.07.2025

It came from outer space. An object from outside our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, 3I/ATLAS is only the third identified macroscopic object as being so alien.

Titan s Cryovolcano
10.06.2005

Investigators suspect the domed feature detailed above is an ice volcano, or cryovolcano, seen in infrared light through the hazy atmosphere on Saturn's moon Titan. Since Titan's surface temperature is around -180...

A Sonic Boom
19.08.2007

Is this what a sonic boom looks like? When an airplane travels at a speed faster than sound, density waves of sound emitted by the plane cannot precede the plane, and so accumulate in a cone behind the plane.

An Anomalous SETI Signal
6.02.2011

No one knows for sure what caused this signal. There is a slight possibility that it just might originate from an extraterrestrial intelligence. The bright colors on the blue background indicate that an anomalous signal was received here on Earth by a radio telescope involved in a Search for Extraterrestrial Intelligence (SETI).

In the Vicinity of the Cone Nebula
12.05.2003

Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars.

Betelgeuse, Betelgeuse, Betelgeuse
16.02.1997

Betelgeuse (sounds a lot like "beetle juice"), a red supergiant star about 600 light years distant, is seen in this Hubble Space Telescope image -- the first direct picture of the surface of a star other than the Sun. A bright, as yet unexplained hotspot is revealed on its surface!

Barnards Loop Around Orion
20.04.2005

Why is the belt of Orion surrounded by a bubble? Although glowing like an emission nebula, the origin of the bubble, known as Barnard's Loop, is currently unknown. Progenitor hypotheses include the winds from bright Orion stars and the supernovas of stars long gone.

The Rosette Nebula in Hydrogen, Oxygen, and Sulfur
11.01.2000

The Rosette Nebula is a large emission nebula located 3000 light-years away. The great abundance of hydrogen gas gives NGC 2237 its red color in most photographs. The wind from the open cluster of stars known as NGC 2244 has cleared a hole in the nebula's center.

Saturns Moon Helene in Color
2.05.2012

Although its colors may be subtle, Saturn's moon Helene is an enigma in any light. The moon was imaged in unprecedented detail last June as the robotic Cassini spacecraft orbiting Saturn swooped to within a single Earth diameter of the diminutive moon.

Lyrid Meteor Streak
23.04.2020

Earth's annual Lyrid Meteor Shower peaked before dawn yesterday, as our fair planet plowed through debris from the tail of long-period comet Thatcher. In crisp, clear and moonless predawn skies over Brown County...