{"id":159835,"date":"2025-09-25T16:18:08","date_gmt":"2025-09-25T16:18:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/159835\/"},"modified":"2025-09-25T16:18:08","modified_gmt":"2025-09-25T16:18:08","slug":"trouble-for-hayabusa2-asteroid-target-smaller-than-expected","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/159835\/","title":{"rendered":"Trouble for Hayabusa2? Asteroid target smaller than expected"},"content":{"rendered":"<p><img fetchpriority=\"high\" decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2025\/09\/Hayabusa2-asteroid-1998ky26-september-2025.jpg\" alt=\"Hayabusa2: A small spacecraft with rectangular solar panels descending onto a much bigger irregular, gray rocky body.\" width=\"800\" height=\"488\" class=\"size-full wp-image-522851\"  \/>Artist\u2019s impression of the Hayabusa2 spacecraft touching down on asteroid 1998 KY26. A new study reveals this asteroid is smaller and spinning much faster than once thought. Image via <a href=\"https:\/\/www.eso.org\/public\/images\/eso2515a\/\" rel=\"noopener nofollow\" target=\"_blank\">ESO<\/a>\/ M. Kornmesser\/ T. Santana-Ros et al.\/ SuperTKG.<\/p>\n<p><a href=\"https:\/\/www.eso.org\/public\/news\/eso2515\/\" rel=\"noopener nofollow\" target=\"_blank\">The European Southern Observatory published this original article on September 18, 2025. Edits by EarthSky.<\/a><\/p>\n<p>Hayabusa2\u2019s target asteroid is smaller and spinning faster than once thought<\/p>\n<p>New observations of asteroid 1998 KY26, the next target of Japan\u2019s Hayabusa2 spacecraft, reveal the space rock to be almost three times smaller and spinning much faster than previously thought. Hayabusa2 is scheduled to touch down on the asteroid in 2031. This is part of the spacecraft\u2019s extended mission following its <a href=\"https:\/\/earthsky.org\/space\/hayabusa-2-spacecraft-approaches-asteroid-ryugu\/\" title=\"Hayabusa 2 arrives at asteroid Ryugu\" rel=\"noopener nofollow\" target=\"_blank\">touchdown on asteroid Ryugu in 2018<\/a>.<\/p>\n<p>Astronomer <a href=\"https:\/\/www.researchgate.net\/profile\/Toni-Santana-Ros\" rel=\"noopener nofollow\" target=\"_blank\">Toni Santana-Ros<\/a>, who led the study on 1998 KY26, <a href=\"https:\/\/www.eso.org\/public\/news\/eso2515\/\" rel=\"noopener nofollow\" target=\"_blank\">said<\/a>:<\/p>\n<p>We found that the reality of the object is completely different from what it was previously described as.<\/p>\n<p>The new observations, combined with <a href=\"https:\/\/www.science.org\/doi\/10.1126\/science.285.5427.557\" rel=\"noopener nofollow\" target=\"_blank\">previous radar data<\/a>, reveal that the asteroid is just 11 meters wide. This means it could easily fit inside the dome of the Very Large Telescope (<a href=\"https:\/\/www.eso.org\/public\/teles-instr\/paranal-observatory\/vlt\/\" rel=\"noopener nofollow\" target=\"_blank\">VLT<\/a>) unit telescope used to observe it. It is also spinning about twice as fast as previously thought. One day on the asteroid lasts only 5 minutes. Previous data indicated that the asteroid was around 30 meters (98 feet) in diameter and completed a rotation in around 10 minutes. <\/p>\n<p>Co-author <a href=\"https:\/\/www.eso.org\/~ohainaut\/\" rel=\"noopener nofollow\" target=\"_blank\">Olivier Hainaut<\/a> said:<\/p>\n<p>The smaller size and faster rotation now measured will make Hayabusa2\u2019s visit even more interesting, but also even more challenging.<\/p>\n<p>This is because a touchdown maneuver, where the spacecraft \u2018kisses\u2019 the asteroid, will be more difficult to perform than anticipated. <\/p>\n<p>The researchers <a href=\"https:\/\/www.nature.com\/articles\/s41467-025-63697-4\" rel=\"noopener nofollow\" target=\"_blank\">published<\/a> the study in the <a href=\"https:\/\/www.nature.com\/ncomms\/editorial-policies\/peer-review\" rel=\"noopener nofollow\" target=\"_blank\">peer-reviewed<\/a> journal Nature Communications on September 18, 2025.<\/p>\n<p>The final target of Hayabusa2<\/p>\n<p>1998 KY26 is set to be the final target asteroid for the Japanese Aerospace eXploration Agency (JAXA)\u2019s Hayabusa2 spacecraft. In its <a href=\"https:\/\/earthsky.org\/space\/hayabusa-2-spacecraft-approaches-asteroid-ryugu\/\" title=\"Hayabusa 2 arrives at asteroid Ryugu\" rel=\"noopener nofollow\" target=\"_blank\">original mission<\/a>, Hayabusa2 explored the 900-meter-diameter <a href=\"https:\/\/earthsky.org\/space\/asteroid-ryugu-potential-to-break-apart-on-impact\/\" title=\"What asteroid Ryugu told us\" rel=\"noopener nofollow\" target=\"_blank\">asteroid 162173 Ryugu<\/a> in 2018. It returned asteroid samples to Earth in 2020. <\/p>\n<p>With fuel remaining, the spacecraft was sent on an extended mission until 2031. That\u2019s when it\u2019s set to encounter 1998 KY26, aiming to learn more about the smallest asteroids. This will be the first time a space mission encounters a tiny asteroid. All previous missions have visited asteroids with diameters in the hundreds or even thousands of meters. <\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2025\/09\/hayabusa2-ryugu-1998KY26-size-comparison-eso-september-2025.jpg\" alt=\"A large, squarish rocky body on the left, with a comparatively minuscule rock to the right, both labeled.\" width=\"800\" height=\"500\" class=\"size-full wp-image-522855\"  \/>Size comparison between asteroids Ryugu, which Hayabusa2 visited in 2018, and 1998 KY26, which it is scheduled to reach in 2031. Illustration via <a href=\"https:\/\/www.eso.org\/public\/images\/eso2515b\/\" rel=\"noopener nofollow\" target=\"_blank\">ESO<\/a>\/ M. Kornmesser\/ T. Santana-Ros\/ JAXA\/ University of Aizu\/ Kobe University.<br \/>\nNew observations<\/p>\n<p>Santana-Ros and his team observed 1998 KY26 from the ground to support preparation for the mission. Because the asteroid is very small and, hence, very faint, studying it required waiting for a close encounter with Earth and using a number of large telescopes around the world, including ESO\u2019s Very Large Telescope (VLT) in Chile\u2019s Atacama Desert.<\/p>\n<p>The observations show that the asteroid has a bright surface and likely consists of a solid chunk of rock, which might have originated from a piece of a planet or another asteroid. However, the team could not completely rule out the possibility that the asteroid is made up of rubble piles loosely sticking together.<\/p>\n<p>Santana-Ros said:<\/p>\n<p>We have never seen a 10-meter-size asteroid in situ, so we don\u2019t really know what to expect and how it will look. The amazing story here is that we found that the size of the asteroid is comparable to the size of the spacecraft that is going to visit it! And we were able to characterize such a small object using our telescopes, which means that we can do it for other objects in the future. Our methods could have an impact on the plans for future near-Earth asteroid exploration or even asteroid mining.<\/p>\n<p>Hainaut added:<\/p>\n<p>Moreover, we now know we can characterize even the smallest hazardous asteroids that could impact Earth, such as the one that hit near <a href=\"https:\/\/earthsky.org\/space\/chelyabinsk-meteor-exploded-over-russia-feb-15-2013\/\" title=\"Chelyabinsk meteor: February 15, 2013\" rel=\"noopener nofollow\" target=\"_blank\">Chelyabinsk, in Russia in 2013<\/a>, which was barely larger than KY26.<\/p>\n<p>Bottom line: New observations of the asteroid that Hayabusa2 is scheduled to touch down on in 2031 reveal it\u2019s smaller and spinning much faster than once thought.<\/p>\n<p><a href=\"https:\/\/www.nature.com\/articles\/s41467-025-63697-4\" rel=\"noopener nofollow\" target=\"_blank\">Source: Hayabusa2 extended mission target asteroid 1998 KY26 is smaller and rotating faster than previously known<\/a><\/p>\n<p><a href=\"https:\/\/www.eso.org\/public\/news\/eso2515\/\" rel=\"noopener nofollow\" target=\"_blank\">Via ESO<\/a><\/p>\n<p>                    EarthSky Voices<br \/>\n                    <a href=\"https:\/\/earthsky.org\/author\/earthskyblog\/\" class=\"post-author-link\" rel=\"nofollow noopener\" target=\"_blank\">View Articles<\/a><\/p>\n<p>                    About the Author:<\/p>\n<p>Members of the EarthSky community &#8211; including scientists, as well as science and nature writers from across the globe &#8211; weigh in on what&#8217;s important to them.<\/p>\n","protected":false},"excerpt":{"rendered":"Artist\u2019s impression of the Hayabusa2 spacecraft touching down on asteroid 1998 KY26. A new study reveals this asteroid&hellip;\n","protected":false},"author":2,"featured_media":159836,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":{"0":"post-159835","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/159835","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=159835"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/159835\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/159836"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=159835"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=159835"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=159835"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}