Black Hole Signature From Advective Disks
15.01.1997

What does a black hole look like? If alone, a black hole would indeed appear quite black, but many black hole candidates are part of binary star systems. So how does a black hole binary system look different from a neutron star binary system? The above drawings indicate it is difficult to tell!

Sirius: The Brightest Star in the Night
11.06.2000

Sirius is the brightest star in the night sky. Sirius is visible on the far left of the above photograph, to the left of the constellation of Orion and Comet Hale-Bopp. Intrinsically, Sirius is over 20 times brighter than our Sun and over twice as massive.

HD 188753: Triple Sunset
5.08.2005

Although it looks like fiction, this artist's vision of sunset on an alien world is based on fact -- the recent discovery of a hot, jupiter-sized planet orbiting in triple star system HD 188753.

The Case of the Very Dusty Binary Star
25.09.2008

For astronomers, close binary star system BD+20 307 originally stood out because it is extremely dusty. A substantial amount of warm dust surrounding it causes the system to appear exceptionally bright at infrared wavelengths. Of course, dust associated with planet formation is often detected around young stars, stars only a few million years old.

X Ray Stars of 47 Tucanae
24.05.2001

A deep optical image (left) of 47 Tucanae shows an ancient globular star cluster so dense and crowded that individual stars can not be distinguished in its closely packed core. An x-ray image of its central regions (inset right) from the Chandra Observatory reveals a wealth of x-ray stars hidden there.

BHB2007: A Baby Binary Star in Formation
16.10.2019

How do binary stars form? To help find out, ESO's Atacama Large Millimeter Array (ALMA) recently captured one of the highest resolution images yet taken of a binary star system in formation. Most...

Upsilon Andromedae: An Extra Solar System
16.04.1999

Yesterday, astronomers announced the discovery of the first system of planets around a normal star other than our Sun. Previously, only single planet star systems had been found. Subtle changes in the wobble of Upsilon Andromedae, a Sun-like star in the constellation of Andromeda, allowed astronomers led by R. Paul Butler (AAO) and Geoffrey W.

APOD: 2024 April 30 Б GK Per: Nova and Planetary Nebula
30.04.2024

The star system GK Per is known to be associated with only two of the three nebulas pictured. At 1500 light years distant, Nova Persei 1901 (GK Persei) was the second closest nova yet recorded. At the very center is a white dwarf star, the surviving core of a former Sun-like star.

T Pyxidis: Recurrent Nova
25.09.1997

What happens when a thermonuclear blast occurs on the surface of a white dwarf star? Over the years astronomers have watched (at a safe distance ...) as, 6,000 light years from Earth in the southern constellation Pyxis, a binary star known as T Pyxidis repeatedly produces these fearsome explosions.

The Nearest Stars
18.03.2001

Which stars are closest to the Sun? The closest is Proxima Centauri, one of three stars that orbit each other about 4 light-years away in the Alpha-Centauri system. Alpha Centauri is easily visible from Earth's