{"id":5755,"date":"2023-03-13T10:00:00","date_gmt":"2023-03-13T10:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=5755"},"modified":"2023-03-02T10:46:02","modified_gmt":"2023-03-02T10:46:02","slug":"new-results-from-nasas-dart-planetary-defence-mission-confirm-we-could-deflect-deadly-asteroids","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/new-results-from-nasas-dart-planetary-defence-mission-confirm-we-could-deflect-deadly-asteroids\/","title":{"rendered":"New results from NASA\u2019s DART planetary defence mission confirm we could deflect deadly asteroids"},"content":{"rendered":"\n
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\n \n CTIO \/ NOIRLab \/ SOAR \/ NSF \/ AURA\/ T. Kareta (Lowell Observatory), M. Knight (US Naval Academy)<\/a><\/span>\n <\/figcaption>\n <\/figure>\n\nEleanor K. Sansom<\/a>, Curtin University<\/a><\/em><\/span>\n\n

What would we do if we spotted a hazardous asteroid on a collision course with Earth? Could we deflect it safely to prevent the impact?<\/p>\n\n

Last year, NASA\u2019s Double Asteroid Redirection Test (DART) mission<\/a> tried to find out whether a \u201ckinetic impactor\u201d could do the job: smashing a 600kg spacecraft the size of a fridge into an asteroid the size of an Aussie Rules football field.<\/p>\n\n

Early results from this first real-world test of our potential planetary defence systems looked promising<\/a>. However, it\u2019s only now that the first scientific results are being published: five papers in Nature have recreated the impact<\/a>, and analysed how it changed the asteroid\u2019s momentum<\/a> and orbit<\/a>, while two<\/a> studies<\/a> investigate the debris knocked off by the impact. <\/p>\n\n

The conclusion: \u201ckinetic impactor technology is a viable technique to potentially defend Earth if necessary\u201d.<\/p>\n\n

Small asteroids could be dangerous, but hard to spot<\/h2>\n\n

Our Solar System is full of debris, left over from the early days of planet formation. Today, some 31,360 asteroids<\/a> are known to loiter around Earth\u2019s neighbourhood. <\/p>\n\n

\n \"A<\/a>\n
\n Asteroid statistics and the threats posed by asteroids of different sizes.<\/span>\n NASA’s DART press brief<\/a><\/span>\n <\/figcaption>\n <\/figure>\n\n

Although we have tabs on most of the big, kilometre-sized ones that could wipe out humanity if they hit Earth, most of the smaller ones go undetected. <\/p>\n\n

Just over ten years ago, an 18-metre asteroid exploded in our atmosphere over Chelyabinsk, Russia<\/a>. The shockwave smashed thousands of windows, wreaking havoc and injuring some 1,500 people<\/a>.<\/p>\n\n

A 150-metre asteroid like Dimorphos wouldn\u2019t wipe out civilisation, but it could cause mass casualties and regional devastation. However, these smaller space rocks are harder to find: we think we have only spotted around 40% of them so far.<\/p>\n\n\n\n

The DART mission<\/h2>\n\n

Suppose we did spy an asteroid of this scale on a collision course with Earth. Could we nudge it in a different direction, steering it away from disaster? <\/p>\n\n

Hitting an asteroid with enough force to change its orbit is theoretically possible, but can it actually be done? That\u2019s what the DART mission set out to determine. <\/p>\n\n

Specifically, it tested the \u201ckinetic impactor\u201d technique, which is a fancy way of saying \u201chitting the asteroid with a fast-moving object\u201d.<\/p>\n\n\n\n

The asteroid Dimorphos was a perfect target. It was in orbit around its larger cousin, Didymos, in a loop that took just under 12 hours to complete.<\/p>\n\n

The impact from the DART spacecraft was designed to slightly change this orbit, slowing it down just a little so that the loop would shrink, shaving an estimated seven minutes off its round trip.<\/p>\n\n

A self-steering spacecraft<\/h2>\n\n

For DART to show the kinetic impactor technique is a possible tool for planetary defence, it needed to demonstrate two things:<\/p>\n\n