Mars and the Star Clusters
30.12.2022

At this year's end Mars still shines brightly in planet Earth's night as it wanders through the head-strong constellation Taurus. Its bright yellowish hue dominates this starry field of view that includes Taurus' alpha star Aldebaran and the Hyades and Pleiades star clusters.

APOD: 2025 May 9 Б IXPE Explores a Black Hole Jet
9.05.2025

How do black holes create X-rays? Answering this long-standing question was significantly advanced recently with data taken by NASAБs IXPE satellite. X-rays cannot exit a black hole, but they can be created in the energetic environment nearby, in particular by a jet of particles moving outward.

APOD: 2025 June 19 Б NGC 3521: Galaxy in a Bubble
19.06.2025

Gorgeous spiral galaxy NGC 3521 is a mere 35 million light-years away, toward the northern springtime constellation Leo. Relatively bright in planet Earth's sky, NGC 3521 is easily visible in small telescopes but often overlooked by amateur imagers in favor of other Leo spiral galaxies, like M66 and M65.

Sirius, Sun, Moon, and Southern Cross
7.07.2000

From left to right are the enclosures of Yepun (ye-poon; Sirius), Antu (an-too; Sun), Kueyen (qua-yen; Moon), and Melipal (me-li-pal; Southern Cross), pictured here as night falls at Paranal Observatory in northern Chile. These are the four 8.2 meter wide telescope units of the European Southern Observatory's Very Large Telescope (VLT).

The Last Moon Shot
9.09.1995

In 1865 Jules Verne predicted the invention of a space capsule that could carry people. In his science fiction story "From the Earth to the Moon", he outlined his vision of constructing a cannon in Florida so powerful that it could shoot a "Projectile-Vehicle" carrying three adventurers to the Moon.

Vela Satellites: The Watchers
5.11.1995

In October of 1963 the US Air Force launched the first in a series of satellites inspired by a recently signed nuclear test ban treaty. Signatories of this treaty agreed not to test nuclear devices in the atmosphere or in space.

Orion's Horsehead Nebula
2.10.1996

The Horsehead Nebula is arguably the most famous nebula on the sky. It is visible as the black indentation to the red emission nebula seen just to the right of center of the above photograph. The bright star near the center is located in the belt of the familiar constellation of Orion.

Infrared Helix
1.09.1997

Five hundred light years from Earth, in the constellation Aquarius, a sun-like star is dying. Its last few thousand years have produced the Helix, a well studied and nearby example of a Planetary Nebula - typical of this final phase of stellar evolution.

Moonquakes Surprisingly Common
27.03.2006

Why are there so many moonquakes? A recent reanalysis of seismometers left on the moon by the Apollo moon landings has revealed a surprising number of moonquakes occurring within 30 kilometers of the surface. In fact, 28 moonquakes were detected in data recorded between 1972 and 1977.

Hale Bopp: The Great Comet of 1997
31.03.2007

Ten short years ago, Comet Hale-Bopp rounded the Sun and offered a dazzling spectacle in planet Earth's night. This stunning view, recorded shortly after the comet's perihelion passage on April 1, 1997, features the memorable tails of Hale-Bopp -- a whitish dust tail and blue ion tail.