X-Rays From Sirius B
6.10.2000

In visible light Sirius A (Alpha Canis Majoris) is the brightest star in the night sky, a closely watched celestial beacon throughout recorded history. Part of a binary star system only 8 light-years away, it was known in modern times to have a small companion star, Sirius B.

Comet Stonehouse
14.05.1998

Comets move against a field of background stars. Their apparent motion is slow but carefull tracking reveals their orbits, allowing these visitors to the inner solar system to be identified as old or new acquaintances. Recently a new comet, designated 1998 H1, was discovered by observer Patrick L.

Collinder 399: The Coat Hanger
22.12.2008

Is this coat hanger a star cluster or an asterism? This cosmic hang-up has been debated over much of last century, as astronomers wondered whether this binocular-visible object is really a physically associated open cluster or a chance projection. Chance star projections are known as asterisms, an example of which is the popular Big Dipper.

Arp 78: Peculiar Galaxy in Aries
7.07.2011

Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries, some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy. Also known...

NGC 602 and Beyond
13.01.2013

Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust, NGC 602 is featured in this stunning Hubble image of the region.

Where Your Elements Came From
24.01.2016

The hydrogen in your body, present in every molecule of water, came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen.

Spiral Galaxy NGC 6744
4.12.2019

Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo and appears as only a faint, extended object in small telescopes.

The Origin of Elements
8.08.2020

The hydrogen in your body, present in every molecule of water, came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen.

APOD: 2025 September 19 Б The NGC 6914 Complex
18.09.2025

A study in contrasts, this colorful cosmic skyscape features stars, dust, and glowing gas in the vicinity of NGC 6914. The interstellar complex of nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy.

APOD: 2026 April 19 Б Eye on the Milky Way
18.04.2026

Have you ever had stars in your eyes? It appears that the eye on the left does, and moreover, it appears to be gazing at even more stars. The featured 27-frame mosaic was taken in 2019 from Ojas de Salar in the Atacama Desert of Chile.