{"id":337334,"date":"2026-03-09T18:21:08","date_gmt":"2026-03-09T18:21:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/337334\/"},"modified":"2026-03-09T18:21:08","modified_gmt":"2026-03-09T18:21:08","slug":"nasas-planetary-defense-test-changed-binary-asteroids-orbit-around-the-sun","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/337334\/","title":{"rendered":"NASA\u2019s Planetary Defense Test Changed Binary Asteroid\u2019s Orbit around the Sun"},"content":{"rendered":"

New measurements show that the DART impact<\/a> in 2022 not only shortened the orbit of the moonlet Dimorphos around its parent asteroid, Didymos, but also subtly shifted the entire binary system\u2019s path around the Sun.<\/p>\n

\"This<\/p>\n

This artist\u2019s illustration shows the ejection of a cloud of debris after NASA\u2019s DART spacecraft collided with the asteroid Dimorphos. Image credit: ESO \/ M. Kornmesser.<\/p>\n

When NASA\u2019s DART spacecraft struck Dimorphos, the impact blasted a huge cloud of rocky debris into space, altering the shape of the asteroid, which measures 170 m (560 feet) wide.<\/p>\n

Because the debris carried its own momentum away from the asteroid, it gave Dimorphos an explosive thrust \u2014 what scientists call the momentum enhancement factor.<\/p>\n

The momentum enhancement factor for DART\u2019s impact was about two, meaning that the debris loss doubled the punch created by the spacecraft alone.<\/p>\n

Earlier research showed<\/a> that the moonlet\u2019s 12-hour orbital period around the 805-m- (nearly 0.5-mile-) wide Didymos shortened by 33 minutes.<\/p>\n

The new study shows the impact ejected so much material from the binary system that it also changed the binary\u2019s 770-day orbital period around the Sun by 0.15 seconds.<\/p>\n

\u201cThe change in the binary system\u2019s orbital speed was about 11.7 microns per second, or 1.7 inches per hour,\u201d said Dr. Rahil Makadia, a researcher at the University of Illinois Urbana-Champaign.<\/p>\n

\u201cOver time, such a small change in an asteroid\u2019s motion can make the difference between a hazardous object hitting or missing our planet.\u201d<\/p>\n

To prove DART had a detectable influence on the binary system, the researchers needed to measure its orbit around the Sun to exquisite precision.<\/p>\n

So, in addition to making radar and other ground-based observations of the asteroid, they tracked stellar occultations, which occur when the asteroid passes exactly in front of a star, causing the pinpoint of light to blink out for a fraction of a second.<\/p>\n

This technique provides extremely precise measurements of the asteroid\u2019s speed, shape, and position.<\/p>\n

The authors relied on volunteer astronomers around the globe who recorded 22 stellar occultations between October 2022 and March 2025.<\/p>\n

\u201cWhen combined with years of existing ground-based observations, these stellar occultation observations became key in helping us calculate how DART had changed Didymos\u2019 orbit,\u201d said Dr. Steve Chesley, a researcher at NASA\u2019s Jet Propulsion Laboratory.<\/p>\n

\u201cThis work is highly weather dependent and often requires travel to remote regions with no guarantee of success.\u201d<\/p>\n

\u201cThis result would not have been possible without the dedication of dozens of volunteer occultation observers around the world.\u201d<\/p>\n

Studying changes in Didymos\u2019 motion also helped the researchers calculate the densities of both asteroids.<\/p>\n

Dimorphos is slightly less dense than previously thought, supporting the theory that it formed from rocky debris shed by a rapidly spinning Didymos.<\/p>\n

This loose material eventually clumped together to form Dimorphos, a \u2018rubble pile\u2019 asteroid.<\/p>\n

Our results demonstrate that targeting the secondary asteroid in binary systems constitutes a possible strategy for kinetic impact deflection, adding to humanity\u2019s planetary defense capabilities.<\/p>\n

\u201cThe DART mission was already a success story. An asteroid system that poses no threat to Earth was carefully selected and NASA crashed a spacecraft into the smaller moon, causing it to orbit its parent asteroid more quickly,\u201d said Dr. Preeti Cowan, a researcher at the University of Auckland.<\/p>\n

\u201cThis new analysis reveals an even more remarkable \u2014 and still safe \u2014 outcome.\u201d<\/p>\n

\u201cThe combined \u2018kick\u2019 from the impact of the spacecraft and the material blasted off the tiny asteroid moon was enough to measurably change the path of the binary system around the Sun.\u201d<\/p>\n

\u201cThe shift may seem small, but where orbits are concerned, even a tiny change applied early enough can have profound consequences.\u201d<\/p>\n

\u201cThis is an important milestone for planetary defense,\u201d said Professor Roberto Armellin, a researcher at the University of Auckland.<\/p>\n

\u201cIn a real hazard scenario, even a very small change applied early enough could cause a potentially dangerous asteroid to miss Earth.\u201d<\/p>\n

\u201cThe next step will come with ESA\u2019s Hera mission, launched in 2024, which will visit the Didymos system later this year to measure the crater, the asteroid\u2019s mass and structure, and the efficiency of the impact.\u201d<\/p>\n

\u201cThese measurements will help turn this historic experiment into a reliable planetary defense technique.\u201d<\/p>\n

The results<\/a> appear in the journal Science Advances.<\/p>\n

_____<\/p>\n

Rahil Makadia et al. 2026. Direct detection of an asteroid\u2019s heliocentric deflection: The Didymos system after DART. Science Advances 12 (10): 10.1126\/sciadv.aea4259<\/p>\n","protected":false},"excerpt":{"rendered":"New measurements show that the DART impact in 2022 not only shortened the orbit of the moonlet Dimorphos…\n","protected":false},"author":2,"featured_media":337335,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[4474,154873,4478,4485,4483,61,60,91,42404,95809,30146,82,3630,9315,154874],"class_list":["post-337334","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-asteroid","tag-binary-asteroid","tag-dart","tag-didymos","tag-dimorphos","tag-ie","tag-ireland","tag-nasa","tag-near-earth-object","tag-near-earth-asteroid","tag-orbit","tag-science","tag-solar-system","tag-star","tag-stellar-occultation"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/337334","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=337334"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/337334\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/337335"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=337334"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=337334"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=337334"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}