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.
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
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 mass of the Sun, 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 star formation through their stellar winds and shock waves 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 Space Observatory 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.
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Dave Finley | EurekAlert!
Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics
What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences