{"id":482379,"date":"2026-06-17T20:00:09","date_gmt":"2026-06-17T20:00:09","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/482379\/"},"modified":"2026-06-17T20:00:09","modified_gmt":"2026-06-17T20:00:09","slug":"radar-observations-reveal-new-clues-about-europas-hidden-interior","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/482379\/","title":{"rendered":"Radar Observations Reveal New Clues about Europa\u2019s Hidden Interior"},"content":{"rendered":"

Using NASA\u2019s Goldstone Solar System Radar and NSF\u2019s Green Bank Telescope, astronomers from the University of California, Los Angeles, confirmed that the icy surface of Jupiter\u2019s moon Europa<\/a> scatters radio energy in an unusually strong and complex way not seen on rocky worlds.<\/p>\n

\"This<\/a><\/p>\n

This artist\u2019s impression shows radar waves from NASA\u2019s Goldstone Solar System Radar pinging Europa; the radar waves penetrate Europa\u2019s icy surface before bouncing back to be collected by NSF\u2019s Green Bank Telescope on Earth. Image credit: NSF \/ AUI \/ NSF\u2019s NRAO \/ P.Vosteen.<\/p>\n

Three of Jupiter\u2019s Galilean satellites \u2014 Europa, Ganymede, and Callisto \u2014 are of particular scientific interest due to their icy shells and suspected subsurface oceans.<\/p>\n

However, the radar properties of the icy satellites have not been measured since observations from 1987 to 1991.<\/p>\n

Because radio waves can penetrate pure ice to considerable depths, radar observations provide a powerful means of characterizing the subsurface properties of the icy shells of these satellites, offering key insights into planetary evolution.<\/p>\n

\u201cRadar delves below what is easily seen, because radio waves can penetrate into the ice, and carry information about its internal structure and purity,\u201d said Tunhui (Tina) Xie, a graduate student at the University of California, Los Angeles.<\/p>\n

In order to address a longstanding gap in the radar studies, Xie and her colleague, Professor Jean-Luc Margot, observed Europa using the Goldstone Solar System Radar and the Green Bank Telescope from 2011 to 2024.<\/p>\n

These observations show that Europa\u2019s radar albedo \u2014 measure of how bright it appears to radar \u2014 is much higher than that of typical planets and asteroids.<\/p>\n

The returning radar signal is dominated by the same circular polarization as the transmitted beam, a hallmark of multiple scattering inside clean, porous ice.<\/p>\n

These properties strongly support an explanation known as the coherent backscatter opposition effect, in which radio waves bounce around within the ice before returning back to the telescope, dramatically boosting the echo.<\/p>\n

Because the researchers observed Europa in a bistatic configuration \u2014 with the Goldstone radar transmitting and both Goldstone and the Green Bank Telescope receiving \u2014 they could also test how the coherent backscatter effect changes with the angle between transmitter, moon, and receiver.<\/p>\n

They found that Europa\u2019s radar brightness stayed roughly constant even when the angle increased, implying that the bright backscatter \u2018peak\u2019 must be broader than the range of angles they sampled, placing a limit on the depth that the radio waves diffused before being absorbed.<\/p>\n

This depth limit offers a new constraint on how transparent Europa\u2019s ice is, and will help scientists interpret upcoming ice\u2011penetrating radar data from spacecraft now en route to study this moon in more detail.<\/p>\n

\u201cFuture planetary science and space flight missions, like NASA\u2019s Europa Clipper, could benefit from this type of radar science,\u201d said Dr. Will Armentrout, a researcher with NSF\u2019s National Radio Astronomy Observatory who supports radar projects.<\/p>\n

\u201cAs the Green Bank Telescope\u2019s radar capabilities evolve, with new technologies currently under development, we\u2019re looking forward to providing even more radar capabilities for the scientific community.\u201d<\/p>\n

The authors will present their results<\/a> today at the 248th meeting of the American Astronomical Society (AAS)<\/a> in Pasadena, California.<\/p>\n

_____<\/p>\n

Tunhui Xie & Jean-Luc Margot. 2026. Radar observations of Europa in 2011-2024: New insights into radar scattering properties. AAS 248, abstract # 481<\/p>\n","protected":false},"excerpt":{"rendered":"Using NASA\u2019s Goldstone Solar System Radar and NSF\u2019s Green Bank Telescope, astronomers from the University of California, Los…\n","protected":false},"author":2,"featured_media":482380,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[35902,242321,59046,2027,4646,3323,111,139,126715,69,242322,56062,147,3145],"class_list":["post-482379","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-europa","tag-goldstone-solar-system-radar","tag-green-bank-telescope","tag-ice","tag-jupiter","tag-nasa","tag-new-zealand","tag-newzealand","tag-nsf","tag-nz","tag-radar-albedo","tag-radio-signal","tag-science","tag-solar-system"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/482379","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=482379"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/482379\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/482380"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=482379"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=482379"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=482379"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}