After NASA filmed the moment that a meteorite impact triggered a massive explosion on the surface of the moon, scientists warned that the Earth could be next if we do not develop the technology to ward off the threat of meteoroids and asteroids threatening the planet. And as part of efforts to protect the Earth from a catastrophic impact event, NASA launched the Double Asteroid Redirection Test (DART) to build a spacecraft that can be launched to bounce off an asteroid threatening the Earth.
The 880-pound meteor, which collided with the lunar surface on September 11, 2013, at a speed of 37, 900 mph, was filmed by NASA scientists. Experts warned after the event that the incident highlighted the grave danger the Earth faces from meteoroids and asteroids orbiting near and crossing the path of its orbit. According to scientists, it is only a matter of time before the Earth experiences a major impact event that could wipe out human civilization if we fail to develop the technology to ward off the threat.
NASA scientists warned that the 2013 impact event demonstrated the danger that the human civilization is facing from the ever-present risk of a major impact event. The impact released energy comparable to an explosion caused by 15 tons of TNT. It was three times more powerful than the previous largest explosion observed on March 17, 2013. It excavated a crater about 131 feet wide, triggering the brightest lunar explosion that scientists had ever observed. The explosion illuminated the night sky with the intensity of a magnitude 4 star. Anyone watching the moon with unaided eyes through a cloudless night sky would have seen the flash at about 8:07 GMT, according to scientists.
“For the past eight years NASA has been monitoring the Moon for signs of explosions caused by meteors. They’ve just seen the biggest explosion in the history of the program.”
Meteor weighing less than 100 pounds hits Moon; impact visible to naked eye! Express (UK), Fri., Jul. 7, 2017: https://t.co/7CyYD7CF3O— Steven Broiles (@sbroiles) July 7, 2017
“It exploded in a flash 10 times as bright as anything we’ve seen before. Anyone looking at the Moon at the moment of impact could have seen the explosion – no telescope required.”
However, experts pointed out that a meteor about the size of the rock that hits the lunar surface is unlikely to pass through the thick blanket of the Earth’s atmosphere. Friction on contact with the Earth’s protective atmosphere means that smaller space objects falling towards the Earth burn up completely before they make impact. However, occasionally, a large meteor survives the entry and eventually impacts the surface or explodes in the air close to the surface.
The Chelyabinsk meteor, for instance, was a 20-meter object that impacted the Earth’s atmosphere, traveling at a speech of about 43,000 mph. It exploded over Chelyabinsk, generating an airburst roughly equivalent to 33 Hiroshima bombs. The airburst damaged about 7,000 buildings and more than 1,500 people were injured.
NASA is now working with the European Space Agency (ESA) to develop a spacecraft that can be used to deflect an asteroid found to be on a collision course with Earth. The agency hopes to be able to conduct the first tests of the new “kinetic impactor” technology in 2022. The test will involve flying a spacecraft toward Didymos, a binary system made up of a large rock, Didymos A, and a smaller rock, Didymos B, orbiting the large rock.
As the spacecraft approaches the Didymos system, it will fire itself, hitting Didymos B at a speed nine times faster than a bullet. It is hoped that the impact of the collision would be sufficient to deflect the asteroid from its course.
Data from the impact will help scientists learn how to carry out controlled impacts that can shift an asteroid away from a course threatening Earth.
“DART would be NASA’s first mission to demonstrate what’s known as the kinetic impactor technique to defend against a potential future asteroid impact,” Lindley Johnson, a NASA planetary defense expert said, according to the Independent.
[Featured Image by Marc Ward/Shutterstock]