Tag: CleanSpace One

News From Space: ESA Sets Sights on Space Debris

space_debrisIt’s no secret that the orbital space lanes are clogged with debris. In fact, our upper atmosphere is so clogged with the remains of dead satellites, old rockets, and assorted space garbage, that initiatives are being planned to remedy the situation. The ESA, for example, has the Clean Space Initiative; and the e.DeOrbit mission that aims to send debris-hunting satellites into orbit to clean up the mess.

The aim of this mission is to clean up the important polar orbits between altitudes of 800 to 1,000 km (500 to 625 mil) that face the prospect of becoming unusable due to the increasing buildup of space debris. As part of the plan, the ESA is also investigating the possibility of using space harpoons to capture large items, such as derelict satellites and the upper stages of rockets.

https://i0.wp.com/images.gizmag.com/gallery_lrg/space-harpoon.jpgThis is just the latest in a series of possible plans to capture debris. In the past, the ESA has revealed that it was looking at capturing space debris in a net, securing it with clamping mechanisms, or grabbing hold of it using robotic arms. However, the latest possibility calls for using capturing debris with a tethered harpoon, which would pierce the debris with a high-energy impact before reeling it in.

Such an approach would not be practical for smaller debris, but is aimed at reeling in uncontrolled multitonne objects that threaten to fragment when colliding with other objects. These sorts of collisions result in debris clouds that would steadily increase in density due to the Kessler syndrome – a scenario in which the density of orbital debris is high enough that collisions generates more debris, increasing the likelihood of further collisions.

Airbus Defence and Space's preliminary design for a space harpoon system (Image: Airbus De...The ESA says the space harpoon concept has already undergone initial investigations by Airbus Defense and Space in Stevenage – two aerospace developers based in the UK. The preliminary design incorporates a penetrating tip, a crushable cartridge to help embed it in the target satellite structure, and barbs to keep it sticking in so the satellite can then be reeled in.

The initial tests involved shooting a prototype harpoon into a satellite-like material to assess its penetration, the strength of the harpoon and tether as the target is reeled in, and the potential for the target to fragment, which would result in more debris that could threaten the e.DeOrbit satellite. The ESA now plans to follow up these initial tests by building and testing a prototype version of the harpoon and its ejection system.

space_laserThe project will examine the harpoon impact, target piercing and the reeling in of objects using computer models and experiments, ultimately leading up to a full hardware demonstration. The space agency has put out the call for bidders to compete for the project contract, and hopes to be sending a working model into orbit by 2021 to conduct some much-needed housecleaning.

Naturally, there are other proposals being considered for debris-hunting. Between the ESA and NASA, there’s also the EPFL’s CleanSpace One debris hunter, and the Universities Space Research Association anti-collision laser concept. And while these remains still very much in the RandD phase, clearing the space lanes is likely to become a central issue once regular missions are mounted to Mars and the outer Solar System.

Sources: gizmag.com, esa.int

Space Junk: The of Bane of the Space Age

janitorOneSpace, or at least the portion which sits in low orbit around our planet, is quite literally a junkyard. Currently, it is estimated that there over 500,000 bits of debris floating above our world, which takes the form of satellite and rocket components, as well as broken down satellites that ceased functioning long ago. Naturally, these objects pose hazards for space flight, and collisions between objects have been known to occur.

In fact, just three years ago, a U.S. and Russian satellite collided over Siberia, generating an estimated 1,000 pieces of new debris at least 4 inches across. In addition, the International Space Station has to periodically adjust its orbit just to get out of the way of traffic. And since exploration and commercial travel to and from the Moon is expected within the near future, something needs to be done to take the garbage out.

cubesatAnd that’s where CleanSpace One comes into play, a janitor satellite that the Swiss Space Center in the Swiss Federal Institute for Technology (EPFL) began developing last year. Specifically designed to target derelict satellites that threaten our communications and information networks. The satellite has a price tag of 11 million dollars, and is expected to be deployed in three to five years.

Naturally, the task before it is a tricky one. In order to do a “launch and seize” operation, the satellite would have to get onto the same orbital plane as its target, latch onto it at high speed, and then de-orbit it. To do this, EPFL is working on an “ultra-compact motor” to get the janitor onto the right track, as well as a grasping mechanism to grab hold of the space junk once its aligned and within distance of it.


And then there’s the efficiency factor. As it stands, a vessel like the CleanSpace One is a one-shot deal design. Once it’s latched onto space junk, it essentially re-enters the atmosphere with it and drops it below, meaning it is unable to gather up multiple pieces of debris and dispose of them discreetly. As such, it would take even a large fleet of janitor satellites quite a long time before they made a dent in all the space junk.

Luckily, there’s another option that has been on the table even longer than the janitor satellite. The reasoning behind this concept is, if you don’t the means to de-orbit all that space junk, just hit it with some photons! When you consider all the debris in orbit and the havoc it plays with the space lanes, not to mention how its only getting worse, a “targeted” approach may just be what the doctor ordered.

space_laserBack in 2011, James Mason, a NASA contractor at the Universities Space Research Association in Moffett Field, Calif., and his colleagues presented a paper claiming that an anti-collision laser system which would target space debris was feasible. Although they acknowledged that more study was required before it could be implemented, they also claimed that lab simulations suggested that the idea would work in practice.

The idea would center around the deployment of a medium-powered laser of 5 to 10 kilowatts to essentially nudge debris off a potential collision course. Rather than eradicate the junk that clutters up the space lanes, this system would be responsible for anticipated crashes and preventing them by ensuring space junk didn’t cross paths with the ISS, satellites, or orbiting shuttles.

space_debrisAnd even that doesn’t represent the entirety of proposed solutions. In addition to janitor satellites and laser, the Russian Space Agency has also been batting around an idea for an orbital pod that would sweep away satellite debris. Details remain sketchy and little information has been released to the public, but the RSA has claimed that they hope to have such a craft ready to go no later than 2023.

Yes, it seems we as a species are entering into phase two of the Space Age. And in this segment of things, orbital pods, offworld habitations, and exploration into the outer Solar System may very well be the shape of things to come. As such, we’re going to need clearer skies above our heads if anything hopes to make it off of Earth without a series fender bender!

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Sources: news.cnet, cbsnews.com