Nasa has just turned an asteroid into an ‘oblong watermelon’
Nasa has managed to change the shape of an asteroid by just hitting it.
The space agency’s Double Asteroid Redirection Test (DART) smashed a refrigerator-sized spacecraft into a stadium-sized asteroid in September to see if they could nudge it.
The test was a bid to see if we could detect and move a hazardous space rock if one was on a collision course with Earth.
The DART mission targeted a 70-meter-wide beast known as Dimorphos, which orbits a larger near-Earth asteroid called Didymos
Before the impact, Dimorphos was roughly symmetrical and had an oblate spheroid shape, similar to a squashed ball that’s wider than its tall.
It could also orbit Didymos in 11 hours and 55 minutes.
However, after DART collided with it, not only did its orbit change but so did its shape.
Dr Shantanu Naidu, who led the study, said: ‘When DART made impact, things got very interesting.
‘Dimorphos’ orbit is no longer circular: Its orbital period is now 33 minutes and 15 seconds shorter. And the entire shape of the asteroid has changed, from a relatively symmetrical object to a ‘triaxial ellipsoid’ – something more like an oblong watermelon.’
The asteroid now orbits its host in 11 hours, 22 minutes, and 3 seconds.
To look at its new shape, the scientists used telescopes on Earth to watch how light reflected off the two asteroids and when the asteroids would cast a shadow on each other and saw Dimorphos was no longer symmetrical.
The team also had access to the spacecraft images, which saw the asteroid as it approached it.
Dr Steve Chesley, a senior research scientist at JPL and study co-author said: ‘Before impact, the times of the events occurred regularly, showing a circular orbit.
‘After impact, there were very slight timing differences, showing something was askew. We never expected to get this kind of accuracy.’
The models are so precise, that they even show that Dimorphos rocks back and forth as it orbits Didymos.
Dr Tom Statler, lead scientist for solar system small bodies at
Nasa said: ‘Seeing separate groups analyze the data and independently come to the same conclusions is a hallmark of a solid scientific result.
‘DART is not only showing us the pathway to an asteroid-deflection technology, it’s revealing new fundamental understanding of what asteroids are and how they behave.’