NASA's ComPair mission will fly to 133,000 feet using high-tech balloon

About the instrument 

The name of the instrument is derived from the two basic approaches for detecting and measuring gamma rays, Compton scattering, and pair creation. 

“Compton scattering occurs when light hits a particle, such as an electron, and transfers some energy to it. Pair production happens when a gamma ray grazes the nucleus of an atom. The interaction converts the gamma ray into a pair of particles – an electron and its antimatter counterpart, a positron,” explained NASA. 

Furthermore, the sophisticated instrument is comprised of four major components: a tracker, a pair of calorimeters, and a detector.

The tracker, which is made up of ten layers of silicon detectors, can pinpoint the exact location of incoming gamma rays in the sky. A high-resolution calorimeter, on the other hand, specifically monitors "lower-energy Compton-scattered gamma rays." Another calorimeter calculates "higher energies of electron-positron pairs."  

And lastly, an anticoincidence detector detects any high-energy charged particles known as cosmic rays that may interfere with the observation, eventually allowing other sensors to disregard them.

As per NASA, ComPair will particularly detect gamma rays with intensities ranging from 200,000 to 20 million electron volts.

The instrument will fly at an altitude of about 133,000 feet

NASA's Goddard Space Flight Center in Greenbelt, Maryland, constructed and tested the ComPair equipment. To evaluate its overall performance, it was tested inside a huge thermal vacuum chamber at Goddard. 

Following successful testing, the instrument will soar to the skies next month on a high-tech balloon facility. “NASA’s scientific balloons offer frequent, low-cost access to near-space to conduct scientific investigations and technology maturation in fields such as astrophysics, heliophysics, and atmospheric research,” noted the statement. 

The balloon flight will take ComPair to a height of nearly 133,000 feet (40,000 meters), which is roughly four times higher than the flying altitude of a typical airliner.

This mission is a collaboration with Goddard, the Naval Research Laboratory in Washington, Brookhaven National Laboratory in Upton, New York, and Los Alamos National Laboratory in New Mexico.