NASA will deploy a huge stratospheric balloon to study newborn stars

It will make detailed 3D maps of gases around the giant stars.

NASA's Goddard Space Flight Center Conceptual Image Lab/Michael Lentz

NASA plans to send an 8.4 foot telescope into the upper stratosphere aboard a “football stadium” sized balloon. ASTHROS (astrophysics stratospheric telescope for high spectral resolution observerations at submillimeter-wavelengths) will study the gases around newly-formed giant stars by observing the far-infrared light they emit. The goal is to get a clearer idea of how star formation and supernova explosions affect their surrounding materials.

Far-infrared wavelengths are normally blocked by our atmosphere, so ASTHROS will need to reach an altitude of 24.6 miles, or about 130,000 feet. Getting that high up with the telescope payload requires a helium-inflated balloon around 400 feet wide, NASA said.

The telescope itself consists of an 8.4-foot wide dish antenna along with mirrors, lenses and detectors designed to capture far-infrared light. Because far-infrared telescopes need to be kept cold, it will also carry a cryocooler that keeps the detectors close to -451.3 degrees Fahrenheit, just a shade above absolute zero.

The Carina Nebula star forming region in the Milky Way
NASA, ESA, N. Smith (University of California, Berkeley) et al., the Hubble Heritage Team (STScI/AURA)

The telescope will observe four targets, including star-forming Carina Nebula (above) in the Milky Way. It will measure the motion, speed and density of gases surrounding newly formed stars and check for the presence of certain types of nitrogen ions. “These nitrogen ions can reveal places where winds from massive stars and supernova explosions have reshaped the gas clouds within these star-forming regions,” NASA wrote.

Those outbursts create something called stellar feedback that can either prevent or accelerate star formation. By learning more about the process, “the team hopes to gain insight into how stellar feedback works and to provide new information to refine computer simulations of galaxy evolution.”

ASTHROS is designed to make two or three loops around the South Pole over three to four weeks, carried by stratospheric prevailing winds. At the end of that time, operators will send a command to separate the balloon from the gondola, which will float back to Earth on a parachute for eventual reuse. The tentative launch date is December, 2023 from Antarctica.