NASA: SOFIA Observes Collapsing Interstellar Clouds Give Birth to Young Stars

Scientists from NASA's airborne telescope SOFIA (Stratospheric Observatory for Infrared Astronomy) have observed an interesting phenomenon: collapsing interstellar clouds that are about to give birth to new stars.

Portions of six interstellar clouds were observed to be caving in, forming giant stars even bigger than our own sun. When gas clouds collapse, their gravity cause them to contract, which in turn produces heat friction. The heat from the contraction causes the core to ignite hydrogen fusion reactions, and out of these, the stars are born.

According to NASA, direct observations of these collapsing clouds--otherwise known as "infalls"--are rare and extremely challenging to capture as they happen quickly. The discovery also enabled astronomers to confirm theoretical models about how interstellar clouds collapse to become stars and the pace at which they fall.

"Detecting infall in protostars is very difficult to observe, but is critical to confirm our overall understanding of star formation," Erick Young of the Universities Space Research Association and SOFIA Science Mission Operations Director said in a statement.

Scientists have been exploring this stellar developmental stage in nine embryonic stars or protostars by measuring the motions of material within them using the observatory's GREAT (German Receiver for Astronomy at Terahertz Frequencies) instrument. They discovered that six of these protostars were collapsing actively.

The SOFIA team operating in Christchurch, New Zealand studies objects observable from southern latitudes, including the center of the Milky Way where star-forming regions are abundant.

"With the Southern Hemisphere deployments of SOFIA, the full inner Milky Way comes into reach for star formation studies," Friedrich Wyrowski, an astronomer at the Max Planck Institute for Radio Astronomy in Bonn, Germany said in the same statement. "This is crucial for observations of the earliest phases of high-mass star formation, since this is a relatively rapid and rare event."

The results were from observations done in the Southern Hemisphere in 2015 and were published in Astronomy and Astrophysics earlier this year. This 2016, SOFIA--a Boeing 747SP jetliner modified to carry a 100-inch diameter telescope--spent seven weeks observing from Christchurch, and the scientific teams involved in the Southern Hemisphere observations are now analyzing the gathered data.

In June this year, SOFIA has also discovered the precise amount and location of water vapor around a newly forming star. The discovery indicated that if planets form around this star, they could receive only a tiny fraction of the water in the system.