{"id":622701,"date":"2026-09-12T19:02:11","date_gmt":"2026-09-12T19:02:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/622701\/"},"modified":"2026-09-12T19:02:11","modified_gmt":"2026-09-12T19:02:11","slug":"the-heavy-disco-ball-satellite-designed-to-do-nothing","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/622701\/","title":{"rendered":"The Heavy Disco-Ball Satellite Designed To Do\u2026 Nothing"},"content":{"rendered":"

Launched in 1976, LAGEOS-1 (LAser GEOdynamic Satellite) is unusual<\/a> in that it contains no instrumentation, no electronics, no power supply, and no means of propulsion. It\u2019s spherical, weighs just under 407 kg, and looks a bit like a disco ball. It may not be accurate to say it does nothing, but unlike most satellites its role is entirely passive. It\u2019s also one of the oldest scientific satellites still in service.<\/p>\n

\"\"<\/a>The lens-like objects covering the surface of LAGEOS-1 are corner cube retroreflectors, which have the nifty effect of always reflecting incident light right back towards its source.<\/p>\n

Ground stations fire short laser pulses at it and measure the time it takes for the light to return, a form of time-of-flight ranging. Since LAGEOS-1\u2019s orbit is highly stable, it provides a reliable reference point for measuring even tiny changes in the Earth itself. The size, shape, rotation, and more of our planet can be measured as a result. LAGEOS data (LAGEOS-2<\/a> was launched in 1992) has also been used in tests of general relativity.<\/p>\n

Its orbit and construction were deliberately chosen so that atmospheric drag and other disturbances would be minimal. The simple, maintenance-free design combined with an extraordinarily stable orbit means LAGEOS is expected to circle our world for millions of years to come.<\/p>\n

LAGEOS-1 also contains a message to the future in the form of two identical plaques prepared by Dr. Carl Sagan<\/a> just in case there\u2019s anyone around to find it some day. Check out the short 1975 video from NASA, embedded just below.<\/p>\n","protected":false},"excerpt":{"rendered":"Launched in 1976, LAGEOS-1 (LAser GEOdynamic Satellite) is unusual in that it contains no instrumentation, no electronics, no…\n","protected":false},"author":2,"featured_media":622702,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[61,60,82,247],"class_list":["post-622701","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-ie","tag-ireland","tag-science","tag-space"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/622701","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=622701"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/622701\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/622702"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=622701"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=622701"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=622701"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}