A claret-colored cloud with a massive heart

Oct 21, 2008
This image, based on data obtained with the Wide Field Imager camera attached to the 2.2-m Max-Planck/ESO telescope through four different filters (B, V, R, and H-alpha), shows the amazing intricacies of the vast stellar nursery Gum 29. At its centre lies the cluster of young stars Westerlund 2. One object at the bottom of the cluster is in fact a system of two of most massive stars known to astronomers. Credit: ESO

(PhysOrg.com) -- Gum 29 is a huge region of hydrogen gas that has been stripped of its electrons (ionised) by the intense radiation of the hot young stars located at its centre. Astronomers call this an HII (pronounced "H-two") region, and this particularly stunning example stretches out across space for over 200 light-years. The name stems from the fact that it is the 29th entry in the catalogue published by Australian astronomer Colin Stanley Gum in 1955.

Embedded deep within the huge, nebulous expanse of Gum 29, the relatively little known cluster of Westerlund 2 is clearly seen in the centre of this image. The latest measurements indicate that it lies at a distance of some 26 000 light-years from Earth, placing it towards the outside edge of the Carina spiral arm of the Milky Way. The cluster's distance has been the subject of intense scrutiny in the past, as it is one of the parameters needed to understand this intriguing object. Westerlund 2 is very young too, with an age of only 1—2 million years.

Previous observations have shown that two stars to the bottom right of the cluster are true leviathans. Together they form what is known as a double system. The two stars have masses of 82 and 83 times that of our Sun and rotate around each other in approximately 3.7 days. They are amongst the most massive stars known to astronomers.

Detailed observations of this intriguing pair have also shown that they are both Wolf-Rayet stars. These are massive stars nearing the end of their lives, expelling vast quantities of material as their final swansong. Observations made in X-rays have subsequently shown that streams of material from each star continually collide, creating a blaze of X-ray radiation.

The image was obtained with the Wide Field Imager (WFI) camera attached to the 2.2-m Max-Planck/ESO telescope at ESO's La Silla observatory site in Chile. Located at an altitude of 2400 metres in the arid Atacama Desert, this observatory sits under some of the clearest and darkest skies on Earth. The WFI excels at studying the farthest depths of the Universe from this unrivalled vantage point.

Provided by ESO

Explore further: POLARBEAR detects curls in the universe's oldest light

add to favorites email to friend print save as pdf

Related Stories

Toothpaste fluorine formed in stars

Aug 21, 2014

The fluorine that is found in products such as toothpaste was likely formed billions of years ago in now dead stars of the same type as our sun. This has been shown by astronomers at Lund University in Sweden, ...

Professor-turned-producer learns the movie biz

Sep 09, 2008

It's not every day that a research scientist and university professor gets to see his work on the silver screen. But in just a few months, Richard W. Siegel will get to watch his name scroll down the giant ...

Recommended for you

Big black holes can block new stars

15 hours ago

Massive black holes spewing out radio-frequency-emitting particles at near-light speed can block formation of new stars in aging galaxies, a study has found.

POLARBEAR seeks cosmic answers in microwave polarization

16 hours ago

An international team of physicists has measured a subtle characteristic in the polarization of the cosmic microwave background radiation that will allow them to map the large-scale structure of the universe, ...

New radio telescope ready to probe

19 hours ago

Whirring back and forth on a turning turret, the white, 40-foot dish evokes the aura of movies such as "Golden Eye" or "Contact," but the University of Arizona team of scientists and engineers that commissioned ...

Exomoons Could Be Abundant Sources Of Habitability

Oct 20, 2014

With about 4,000 planet candidates from the Kepler Space Telescope data to analyze so far, astronomers are busy trying to figure out questions about habitability. What size planet could host life? How far ...

Partial solar eclipse over the U.S. on Thursday, Oct. 23

Oct 17, 2014

People in most of the continental United States will be in the shadow of the Moon on Thursday afternoon, Oct. 23, as a partial solar eclipse sweeps across the Earth. For people looking through sun-safe filters, from Los Angeles, ...

User comments : 0