{"id":2690,"date":"2017-04-12T02:02:27","date_gmt":"2017-04-12T02:02:27","guid":{"rendered":"http:\/\/chief-exec.com\/?p=2690"},"modified":"2017-05-12T16:03:20","modified_gmt":"2017-05-12T16:03:20","slug":"space-junk-too-fast-too-furious","status":"publish","type":"post","link":"https:\/\/chief-exec.com\/?p=2690","title":{"rendered":"Space junk: too fast, too furious"},"content":{"rendered":"

The European Space Agency estimates there are 750,000 objects larger than 1 cm orbiting Earth. The risks from collisions are growing as the outer atmosphere becomes increasingly crowded, reports James Fitzgerald<\/em>.<\/span><\/h4>\n

Most people wouldn\u2019t step out onto a road with thousands of vehicles travelling at 40,000 km\/h, and neither would they put an expensive piece of equipment in the way of such formidable traffic. But this is the scenario faced by space agencies as they launch multi-million dollar satellites into Earth\u2019s orbit.<\/p>\n

The European Space Agency estimates there are 750,000 objects larger than 1 cm orbiting Earth. Many will be fragments from collisions in space. About 18,000 of these projectiles are regularly monitored by existing surveillance systems<\/a>, but the risks from collisions are growing as the outer atmosphere becomes increasingly crowded, with the prospect of large constellations of communication satellites entering the fray.<\/p>\n

\u201cSeveral thousand new satellites are planned for launch into low Earth orbit in the next few years,\u201d says Marshall Kaplan of Launchspace Technologies. \u201cThat will make the debris problem much worse. At some point, no one knows when, there will be so many collisions that we won\u2019t be able to operate safely in low Earth orbit anymore.\u201d<\/p>\n

The \u00a0American company plans to send platforms the size of football pitches into low orbit to sweep up debris, which would also have sensors to track satellites and miscellaneous objects \u2013 potentially more accurately than ground-based systems.<\/p>\n

Each orbital collision creates debris that further increases the chances of collisions in a cascade effect that was outlined by NASA scientist Donald Kessler in a 1978 paper. The \u201cKessler syndrome\u201d will be on the minds of scientists, engineers, managers, space operators and policy-makers at the European conference on space debris later this month. Although there is a consensus among spacefaring nations about the need to mitigate effects from collisions and the cascade effect, it has become evident that remediation measures will be required to limit the number of objects in circulation.<\/p>\n

Traditionally satellites facing retirement either meet a fiery end, after being directed into the lower atmosphere to burn out, or are elevated 200km above active satellites into a grave region. This will soon happen with Meteosat-7, a weather satellite that has a geostationary orbit 36,000km above the Indian Ocean.<\/p>\n

However, even this zone may one day need to be cleared out.<\/p>\n

\u201cWe recognise that the graveyard orbit can only be a temporary solution,\u201d Milan Klinc, a flight dynamics engineer at EUMETSAT, recently told Space.com. \u201cWe are only in the early, theoretical stages at the moment, but we need to look at a permanent solution involving removing or collecting the old satellites.\u201d<\/p>\n

In March, during a spacewalk around the International Space Station (ISS), two NASA astronauts lost a thermal shield, which entered an orbit close to the station.<\/p>\n

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‘Peggy I don’t have a shield’: ISS astronauts lose key piece of equipment \u2013 video https:\/\/t.co\/rl24K2dbZh<\/a><\/p>\n

\u2014 The Guardian (@guardian) March 31, 2017<\/a><\/p><\/blockquote>\n