{"id":21884,"date":"2021-12-05T10:23:36","date_gmt":"2021-12-05T04:38:36","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=21884"},"modified":"2021-12-05T14:33:33","modified_gmt":"2021-12-05T08:48:33","slug":"one-way-phone-call-at-mars","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/one-way-phone-call-at-mars\/","title":{"rendered":"One-way phone call at Mars"},"content":{"rendered":"\n

This November, ESA\u2019s Mars Express spacecraft carried out a series of experimental communication tests with the Chinese (CNSA) Zhurong Mars rover. Mars Express successfully caught data sent up \u2018in the blind\u2019 by the rover and relayed them to Earth where they were forwarded to the Zhurong team in China.<\/p>\n\n\n\n

The Zhurong rover, commanded by the Tianwen-1 orbiter, points its radio up at the Martian sky. Any minute now, ESA\u2019s Mars Express will begin to pass overhead. Zhurong starts transmitting a signal up into space. It has no way of knowing if its message is being received.<\/p>\n\n\n\n

Landers and rovers on Mars gather data that help scientists answer fundamental questions about the geology, atmosphere, surface environment, history of water, and potential for life on the Red Planet.<\/p>\n\n\n\n

To get these insights to Earth, they first transmit the data up to spacecraft in orbit around Mars. These orbiters then use their much larger, more powerful transmitters to \u2018relay<\/a>\u2019 the data across space to Earth.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

\u201cNormally, an orbiter like ESA\u2019s Mars Express first sends down a hail signal to a rover as a \u2018hello\u2019,\u201d says James Godfrey, Mars Express Spacecraft Operations Manager.<\/p>\n\n\n\n

\u201cThe rover then sends back a response to establish stable communications and begin the two-way exchange of information. But this relies on the rover\u2019s radio system being compatible with the orbiter\u2019s.\u201d<\/p>\n\n\n\n

As Mars Express transmits its \u2018hello\u2019 signal using communication frequencies that are different from those the Chinese Zhurong Mars rover receives, two-way communication is not possible.<\/p>\n\n\n\n

But in the other direction, Zhurong can transmit<\/em> a signal using a frequency that Mars Express can receive.<\/p>\n\n\n\n

The relay radio on Mars Express has a mode that allows this one-way communication \u2013 communication \u2018in the blind\u2019 where the sender can\u2019t be sure if their signal is being received \u2013 but until now, the technique hadn\u2019t been tested on the spacecraft.<\/p>\n\n\n\n

In November, ESA\u2019s Mars Express and CNSA\u2019s Zhurong teams carried out a series of experimental communication tests<\/a> in which Mars Express used this \u2018in the blind\u2019 mode to listen for signals sent to it by the Zhurong Rover.<\/p>\n\n\n\n

The experiments culminated in a successful test on 20 November.<\/p>\n\n\n\n

\u201cMars Express successfully received the signals sent by the rover, and our colleagues in the Zhurong team confirmed that all the data arrived on Earth in very good quality.\u201d says ESA\u2019s Gerhard Billig.<\/p>\n\n\n\n

\u201cWe\u2019re looking forward to carrying out more tests in the future to continue to experiment and further improve this method of communicating between space missions.\u201d<\/p>\n\n\n\n

The data relayed by Mars Express arrived on Earth at ESA\u2019s ESOC space operations centre<\/a> in Darmstadt, Germany, via deep-space communication antennas. From there, these data were forwarded to the Zhurong team at the Beijing Aerospace Flight Control Center, who confirmed the success of the test.<\/p>\n","protected":false},"excerpt":{"rendered":"

This November, ESA\u2019s Mars Express spacecraft carried out a series of experimental communication tests with the Chinese (CNSA) Zhurong Mars rover. <\/p>\n","protected":false},"author":2,"featured_media":21885,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[38,17,20],"tags":[],"class_list":["post-21884","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-curiosity","category-research","category-space-news"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",889,500,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-200x200.png",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-675x380.png",675,380,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-768x432.png",750,422,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-675x380.png",675,380,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",889,500,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",889,500,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",889,500,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",870,489,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",600,337,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",600,337,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-760x490.png",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-550x360.png",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express-95x65.png",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",640,360,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",96,54,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/12\/mars-express.png",150,84,false]},"author_info":{"info":["RevoScience"]},"category_info":"Curiosity<\/a> Research<\/a> Space\/ AstroPhysics<\/a>","tag_info":"Space\/ AstroPhysics","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/21884","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=21884"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/21884\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/21885"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=21884"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=21884"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=21884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}