One capture concept being explored through ESA’s e.Deorbit system study for Active Debris Removal – capturing the satellite in a net attached to either a flexible tether – as seen here – or a rigid connection. ((c) ESA)
Going back in time to tackle 21st century problems, the European Space Agency (ESA) has been testing the effectiveness of some old fishing net technology as a way to grab and retrieve larger pieces of debris in space such as inactive satellites or spent rocket boosters.
The space agency tested the old fishing net technology, which has been dated to 8,300 BC, aboard a Falcon 20 aircraft that produced 20 seconds of weightlessness by flying in parabolic arcs.
“We shot nets out of a compressed air ejector at a scale-model satellite,” explained ESA engineer Kjetil Wormnes in a press release.
The ESA researchers used the compressed air ejector to shoot 20 nets traveling at different speeds toward the satellite model over a two-day period.
Delta 2nd Stage Stainless Steel Cylindrical Propellant Tank; landed in Georgetown, Texas ( NASA Orbital Debris Program Office)
The nets were colored in rainbow shades so that the experiment’s four high-speed HD cameras could easily and accurately track them. And they were weighted at each corner to allow them to better entangle the model satellite.
“The good news is they worked extremely well –- so much so that the nets usually had to be cut away with a knife before we could shoot again,” said Wormnes.
The researchers used two different types of nets in their experiments — one that was described as a thinner-spun version, and the other was thicker with a woven design. Of the two, the researchers said they found the thinner-spun type to be more effective in snagging the model satellite.
The net technology tests were done to help ESA determine the best way to snatch uncontrolled, tumbling and potentially dangerous large chunks of space debris.
ESA’s Clean Space initiative hopes to cut back on space technology threats for both space and terrestrial environments. Part of that effort is the e.Deorbit mission, set for 2021 and intended to help control the amount of large debris in busy orbits around Earth.
But, just how the space junk will be retrieved in this mission is still being determined. So far, ESA is considering the use of a robotic arm, a harpoon, an ion beam, and now perhaps this newly tested fishing net method.
Computer generated image of space debris from a distant vantage point to provide a good view of the object population in the geosynchronous region (NASA)
Wormnes said the main advantage for using the “fishing net” method, whether it’s for e.Deorbit or perhaps other future space debris removal missions, is that the nets can grab onto a wide range of target shapes that spin at varying rotation rates.
The Earth is surrounded with thousands of pieces of debris. They range from tiny paint flecks that have chipped from old spacecraft to discarded astronaut tools to inactive satellites and used rocket boosters that have accumulated in space since the beginning of the space race in the late 1950’s.
The US Military’s Space Surveillance Network, which has been using various technologies since the 1957, keeps an eye on more than 22,000 softball-sized or larger pieces of space debris.
NASA’s Orbital Debris Program (ODP) at the Johnson Space Center in Texas, is also keeping an eye on the ever-expanding junkyard of space.
Comments are closed.