The TechEdSat-4 satellite, a CubeSat, was recently jettisoned from the International Space Station (ISS) and after reaching a designated orbit will use a parachute-like “exo-brake” to slow it down enough to safely reenter Earth’s atmosphere, according to NASA.
NASA testing exo-brake technology
The TechEdSat-4 satellite, a CubeSat, was recently jettisoned from the International Space Station (ISS) and after reaching a designated orbit will use a parachute-like “exo-brake” to slow it down enough to safely reenter Earth’s atmosphere, according to NASA.
Requiring no propellant, the TechEdSat-4 is being considered as a low-cost alternative for sending samples back to Earth.
The principle behind the exo-brake is the same one that causes orbital decay and sends old satellites plummeting back to Earth. Though space officially starts 62 mi (100 km) up, the atmosphere actually extends hundreds of miles above that as the exosphere. It’s extremely tenuous, but there is still enough air molecules present to gradually slow down satellites until they succumb to the pull of gravity, re-enter and burn up.
Exo-braking exploits the exosphere by deploying a drogue chute with an area of about one square meter per kilogram of satellite. The technique was first tested by TechEdSat-3 in 2013 and TechEdSat-4 is carrying a second-generation version.
“The exo-brake is a self-stabilizing exospheric deorbiting mechanism that will allow us to return a payload to Earth fairly rapidly from an orbital platform, like the International Space Station,” says Marcus Murbach, the TechEdSat-4 principal investigator at NASA’s Ames Research Center at Moffett Field, California. “We were able to send commands and receive data to and from the satellite via the onboard modem using only a laptop and email account. This capability may greatly benefit the entire nanosatellite community.”
“This is what we need. To catch up, which of course cannot be done overnight, especially if it goes about a complex process of creating complicated electronic products. Russia needs to catch up with many of its competitors. This is a well-known fact, but it is quite possible to overcome all problems and difficulties.”
