Map of Cepheus E emphasizing the jets of material flowing to the upper left and lower right from the protostar. The protostar itself is the central yellow-red 'blob" in the colored background map of hydrogen emission made at a wavelength of 4.5 microns by the Spitzer infrared space telescope. The contour curves show the strength of emission from cool carbon monoxide gas measured by the Plateau de Bure radio telescope located in the French Alps. Lefloch et al. used GREAT on SOFIA to measure the amount and velocity of hot carbon monoxide gas at multiple positions along both "wings" of the outflow jet.
Credits: Lefloch et al. 2015. Figure 1
Scientists on board NASA’s flying telescope, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, caught sight of roiling material streaming from a newly formed star, which could spark the birth of a new generation of stars in the surrounding gas clouds.
Many stars in the early stages of formation expel large amounts of
super-heated material in two streams, known as bipolar outflows or jets,
which flow in opposite directions. A team of scientists led by Bertrand
Lefloch from the University of Grenoble Alpes, France, observed these
jets coming from Cepheus E, a massive protostar at the earliest stage of
star formation, located 2,400 light years from Earth in the
constellation Cepheus. Lefloch’s team is studying how such outflows
originate and the effects those jets have on star formation in the
surrounding clouds.
“The SOFIA observations have unveiled new clues to how these jets
powered by protostars actually form, and clarified the physical
conditions reigning in these objects,” Lefloch said. Lefloch’s team has
determined that the jets are less than 1,000 years old, making this
process astronomically very young. The powerful jets are shown to extend
out to a distance of 118 billion miles and the jet material is moving
at speeds between 200,000 and 300,000 mph.
The team’s observations were made using SOFIA’s Upgraded German Receiver at Terhertz Frequencies, upGREAT,
to make a map of the hottest and densest portions of the matter ejected
from Cepheus E. The researchers identified three main parts of the
outflow: the jet itself, regions of the surrounding gas and dust cloud
through which the jets have plowed through, and the shock waves at the
farthest ends of the jets affecting the surrounding cloud.
The last area is of particular interest, in that it could be the
future birthplace of additional stars. The formation of new stars is
thought to be triggered by these shocks. The team was able to map the
hottest material because of the unique wavelength range available to
SOFIA and the upGREAT instrument. The maps also contained more detail
than other observatories because of the size of SOFIA’s telescope.
“The upGREAT instrument now has more detectors, allowing us to make
more detailed maps of celestial gas molecules very rapidly,” said
Universities Space Research Association’s SOFIA Science Mission Director
Harold Yorke. “The physical conditions in the outflowing gas are still
poorly known, and we are just now employing new instruments enabling us
to study this process. These observations demonstrate that SOFIA is a
powerful tool to map the areas around star-forming regions, providing
data that are helping to develop a more comprehensive picture of star
formation.”
Astronomers are excited about these SOFIA observations because they
provide high-resolution data that are complemented by observations
conducted by ground and space-based telescopes, including the Atacama
Large Millimeter Array, ALMA, and the Herschel Space Observatory. Results from the Le Floch team’s observations were published in the journal Astronomy and Astrophysics.
Further investigations of this target will be necessary to definitively
determine how this violent activity impacts star formation.
SOFIA is a Boeing 747SP jetliner modified to carry a 100-inch
diameter telescope. It is a joint project of NASA and the German
Aerospace Center, DLR. NASA’s Ames Research Center in California’s
Silicon Valley manages the SOFIA program along with science and mission
operations in cooperation with the Universities Space Research
Association headquartered in Columbia, Maryland, and the German SOFIA
Institute (DSI) at the University of Stuttgart. The aircraft is based at
NASA Armstrong Flight Research Center's Hangar 703, in Palmdale,
California.
For More Information:
Study SOFIA's science mission and scientific instruments at: http://www.sofia.usra.edu • http://www.dsi.uni-stuttgart.de/index.en.html
Editor: Kassandra Bell
Source: NASA/SOFIA
