The dispatch of an observatory to space is usually done by rocket. You stuff the spacecraft into a payload bay, launch it into space, and then deploy it into orbit around Earth. For NASA’s ASTHROS observatory, the space agency has devised a completely different strategy to bring its hardware to the edge of space: a very, very large balloon.
ASTHROS, which is short for Astrophysics Stratospheric Telescope for high-spectral resolution observations at submillimeter wavelengths, includes some high-tech instruments for observing space, but first, it has to break free of much of Earth’s atmosphere. To make that happen, NASA’s Jet Propulsion Laboratory is designing a balloon that stretches 400 feet wide, which is about the size of a football stadium.
The mega balloon will transport ASTHROS at an altitude of almost 25 miles. As NASA explains, that’s right at a sweet spot between the upper limit of commercial aircraft and the edge of space itself:
ASTHROS observes far infrared light, or light with much longer wavelengths than is visible to the human eye. To do that, ASTHROS will have to reach an altitude of approximately 130,000 feet (24.6 miles), approximately four times higher than the commercial airplanes that fly. Although it is still well below the limit of space (approximately 62 miles above Earth’s surface), it will be high enough to observe wavelengths of light blocked by Earth’s atmosphere.
The mission will see that the balloon transports the observatory around the South Pole, where it can look out into space, using its far-infrared instruments to capture light and make new observations. NASA’s Jet Propulsion Laboratory believes the balloon will be able to keep hardware flying high for up to 28 days, allowing it to circle the South Pole up to three times.
“I think stellar feedback is understood to be the primary regulator of star formation throughout the history of the universe,” Jorge Pineda, ASTHROS principal investigator at the Jet Propulsion Laboratory, said in a statement. “Computer simulations of the evolution of galaxies still cannot replicate the reality we see in the cosmos. The nitrogen mapping we’ll be doing with ASTHROS has never been done before, and it will be exciting to see how that information helps make those models more accurate. “
Once the mission is complete, the team will remotely detach the globe from the gondola that holds the ASTHROS hardware. When the nacelle is detached, a parachute will be activated which will provide the sensitive hardware with a relatively smooth landing. Scientists will then retrieve the machine and make any necessary repairs or changes before sending it back to heaven.