Map of galactic clouds where stars are born takes shape

Sep 11, 2013
Map of galactic clouds where stars are born takes shape
The Mopra Telescope in Coonabarabran, NSW, Australia, that is used to map the location of the giant gas clouds in the Milky Way where stars are born. Credit: UNSW

A UNSW-led team of astronomers has begun to map the location of the most massive and mysterious objects in our galaxy – the giant gas clouds where new stars are born.

Using a telescope at Coonabarabran that narrowly escaped devastation in a recent bushfire, the team identifies the galactic clouds of molecular gas - which can be up to 100 light years across - from the carbon monoxide they contain.

"On Earth, carbon monoxide is poisonous – a silent killer. But in space, it is the second most abundant molecule and the easiest to see," says Professor Michael Burton, of the UNSW School of Physics, who leads the team.

"One of the largest unresolved mysteries in galactic astronomy is how these giant, diffuse clouds form in the . This process plays a key role in the cosmic cycle of birth and death of stars."

A research paper on the first stage of the work – covering a region of the sky about the size of four full moons – is published in the journal Publications of the Astronomical Society of Australia.

The carbon monoxide survey of the Southern Milky Way is being carried out with the 22 metre Mopra millimetre wave telescope at Coonabarabran. While the adjoining workshop, office, and accommodation wing were destroyed in the bushfire in January, the telescope's control room survived because it was encased in brick.

The international team is also searching for "dark" clouds – unseen clouds that contain very little . It is assumed these clouds are mostly made up of which is too cold to detect.

The team is using telescopes in Antarctica and Chile to search for these dark clouds, based on the presence of , rather than , in the clouds.

"Taken together, these three surveys will provide us with a picture of the distribution and movement of gas clouds in our galaxy," says Professor Burton.

Dark clouds, if found, could also be the "missing" source of gamma rays, which are produced when high-energy cosmic rays interact with the nuclei of gas atoms or molecules they encounter when travelling through space.

"The source of more than 30 per cent of gamma rays remains unidentified – another big mystery our research could throw light on," says Professor Burton.

Some of the options for how large giant molecular clouds form include the gravitational collapse of an ensemble of small clouds into a larger one, or the random collision of small clouds which then agglomerate.

About one star per year, on average, is formed in the Milky Way. Stars that explode and die then replenish the , as well as moving the gas about and mixing it up.

Explore further: Planet-forming lifeline discovered in a binary star system

More information: journals.cambridge.org/action/… e=online&aid=8970394

add to favorites email to friend print save as pdf

Related Stories

Free-floating planets may be born free

Aug 19, 2013

Tiny, round, cold clouds in space have all the right characteristics to form planets with no parent star. New observations, made with Chalmers University of Technology telescopes, show that not all free-floating ...

Hubble finds source of Magellanic Stream

Aug 08, 2013

(Phys.org) —Astronomers using the NASA/ESA Hubble Space Telescope have solved the 40-year-old mystery of the origin of the Magellanic Stream, a long ribbon of gas stretching nearly halfway around the Milky ...

Today in the Milky Way: Cloudy skies

Jul 02, 2012

(Phys.org) -- Adam Block of the UA's Mount Lemmon SkyCenter brings us a rare view of the clouds wafting through our Milky Way in this Astronomy Picture of the Day.

Dark clouds in space

Sep 13, 2011

(PhysOrg.com) -- Infrared dark clouds (IRDCs) are dark patches in the sky seen against the continuous, bright infrared background produced by our galaxy. IRDCs are rich in molecules and relatively dense, cool ...

Recommended for you

Planet-forming lifeline discovered in a binary star system

18 hours ago

Scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) have detected a streamer of dust and gas flowing from a massive outer disk toward the inner reaches of a binary star system. This never-before-seen ...

Astronomy & Astrophysics: Planck 2013 results

22 hours ago

Astronomy & Astrophysics is publishing a special feature of 31 articles describing the data gathered by Planck over 15 months of observations and released by ESA and the Planck Collaboration in March 2013. ...

Existence of a group of 'quiet' quasars confirmed

23 hours ago

Aeons ago, the universe was different: mergers of galaxies were common and gigantic black holes with masses equivalent to billions of times that of the Sun formed in their nuclei. As they captured the surrounding ...

Tremendously bright pulsar may be one of many

Oct 27, 2014

Recently, a team of astronomers reported discovering a pulsating star that appears to shine with the energy of 10 million suns. The find, which was announced in Nature, is the brightest pulsar – a type ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.