Monitoring M2-9
18.06.2007

Exploring the myriad shapes found in the cosmic zoo of planetary nebulae, some astronomers have focused on the intriguing example of M2-9. About 2,100 light-years away and over one light-year across, M2-9 is known as a twin jet or butterfly nebula in reference to its striking bipolar symmetry.

Mira: The Wonderful Star
5.05.2005

To seventeenth century astronomers, Omicron Ceti or Mira was known as a wonderful star - a star whose brightness could change dramatically in the course of about 11 months. Modern astronomers now recognize an entire class of long period Mira-type variables as cool, pulsating, red giant stars, 700 or so times the diameter of the Sun.

Proxima Centauri: The Closest Star
18.01.2016

Does the closest star to our Sun have planets? No one is sure -- but you can now follow frequent updates of a new search that is taking place during the first few months of this year. The closest star, Proxima Centauri, is the nearest member of the Alpha Centauri star system.

XZ Tauri System Ejects Gas Bubble
21.09.2000

Why is the binary star system XZ Tauri emitting a hot bubble of expanding gas? Although astronomers can only presently speculate, the Hubble Space Telescope clearly documents this unusual behavior in three dramatic photographs over the past five years.

HD 163296: Jet from a Star in Formation
22.06.2021

How are jets created during star formation? No one is sure, although recent images of the young star system HD 163296 are quite illuminating. The central star in the featured image is still forming but seen already surrounded by a rotating disk and an outward moving jet.

Symbiotic R Aquarii
29.06.2017

A long recognized naked-eye variable star, R Aquarii is actually an interacting binary star system, two stars that seem to have a close, symbiotic relationship. About 710 light years away, it consists of a cool red giant star and hot, dense white dwarf star in mutual orbit around their common center of mass.

Stars of NGC 206
2.04.1999

Nestled within the dusty arms of the large spiral galaxy Andromeda (M31), the star cluster NGC 206 is one of the largest star forming regions known in our local group of galaxies. The beautiful...

X Ray Stars in M15
20.09.2001

Side by side, two x-ray stars greeted astronomers in this false-color Chandra Observatory x-ray image of a region near the core of globular star cluster M15. The greeting was a pleasant surprise, as all previous x-ray images of the cluster showed only one such source where Chandra's sharper x-ray vision now reveals two.

HH111's 12 Light-Year Star Jet
21.03.2000

The complex interactions of three stars in the Orion B molecular cloud complex have resulted in the ejection of particles along a 12 light-year long jet. One of the stars in the HH111 system has apparently also been ejected leaving two stars tightly bound in a binary orbit.

HR 4796A: A Recipe for Planets
22.04.1998

Two hundred and twenty light years from Earth, planets are forming. Recent observations of the binary star system HR 4796 have shown that one of the stars is surrounded by a dusty gaseous disk. This disk is of the right size, age, and density for dust pellets to accrete surrounding matter.