Astronomers get rare peek at early stage of star formation

Mar 14, 2012
New observations show 'pristine' example of second stage of star formation shown in this graphic. (Images not to scale.) CREDIT: Bill Saxton, NRAO/AUI/NSF

(PhysOrg.com) -- Using radio and infrared telescopes, astronomers have obtained a first tantalizing look at a crucial early stage in star formation. The new observations promise to help scientists understand the early stages of a sequence of events through which a giant cloud of gas and dust collapses into dense cores that, in turn, form new stars.

The scientists studied a giant cloud about 770 light-years from Earth in the constellation Perseus. They used the European Space Agency's Herschel Space Observatory and the National Science Foundation's Green Bank Telescope (GBT) to make detailed observations of a clump, containing nearly 100 times the , within that cloud.

Stars are formed, astronomers think, when such a cloud of gas and dust collapses gravitationally, first into clumps, then into dense cores, each of which can then begin to further collapse and form a young star. The details of how this happens are not well understood. One difficulty is that most regions where this process is underway already have formed stars nearby. Those stars affect subsequent nearby through their and when they explode as supernovae.

"We have found the first clear case of a clump of potentially star-forming gas that is on the verge of forming dense cores, and is unaffected by any nearby stars," said James Di Francesco, of the University of Victoria, Canada.

"Finding such a 'pristine' clump of gas that may be starting to form dense cores is a key to gaining a fuller understanding of the early stages of star formation," said Sarah Sadavoy, a graduate student also of the University of Victoria. "This is a rare find," she added.

The far-infrared images from the Herschel were obtained as part of the Herschel Gould Belt Survey key program. They revealed previously-unseen substructures within the clump that may be precursors to cores with the potential to form individual stars. The astronomers used the GBT to study the motions and temperatures of molecules, primarily ammonia, within these substructures. These GBT observations indicated that one of the substructures is likely to be gravitationally bound and thus farther along the path to condensing into a core than the others.

"This may be the first observation ever of a core precursor," DiFrancesco said.

The entire clump, the scientists say, could be expected to form about ten new stars.

"This region appears to be an excellent candidate for future core formation, and thus is an ideal area for additional studies that can help us understand how this process works without the triggering effect of winds from other stars and shocks from supernova explosions," Sadavoy said.

The scientists will publish their results in the journal Astronomy & Astrophysics.

Explore further: Millisecond pulsars clearly demonstrate that pulsars are neutron stars

Related Stories

Herschel finds a hole in space

May 11, 2010

(PhysOrg.com) -- ESA's Herschel infrared space telescope has made an unexpected discovery: a hole in space. The hole has provided astronomers with a surprising glimpse into the end of the star-forming process.

AKARI's view on birth and death of stars

Aug 28, 2006

AKARI, the Japan Aerospace Exploration Agency (JAXA) infrared astronomical satellite with ESA participation, is continuing its survey of the sky and its mapping of our cosmos in infrared light. New exciting ...

Young stars flicker amidst clouds of gas and dust

Feb 29, 2012

(PhysOrg.com) -- Astronomers have spotted young stars in the Orion nebula changing right before their eyes, thanks to the European Space Agency's Herschel Space Observatory and NASA's Spitzer Space Telescope. ...

Stellar embryos

Jan 23, 2012

(PhysOrg.com) -- Stars form as gravity coalesces the gas and dust in interstellar clouds until the material produces clumps dense enough to become stars. But precisely how this happens, and whether or not ...

Baby stars in the Rosette cloud

Apr 12, 2010

Herschel's latest image reveals the formation of previously unseen large stars, each one up to ten times the mass of our Sun. These are the stars that will influence where and how the next generation of stars ...

Recommended for you

How small can galaxies be?

Sep 29, 2014

Yesterday I talked about just how small a star can be, so today let's explore just how small a galaxy can be. Our Milky Way galaxy is about 100,000 light years across, and contains about 200 billion stars. Th ...

The coolest stars

Sep 29, 2014

One way that stars are categorized is by temperature. Since the temperature of a star can determine its visual color, this category scheme is known as spectral type. The main categories of spectral type are ...

Simulations reveal an unusual death for ancient stars

Sep 29, 2014

(Phys.org) —Certain primordial stars—those 55,000 and 56,000 times the mass of our Sun, or solar masses—may have died unusually. In death, these objects—among the Universe's first-generation of stars—would ...

User comments : 0