DART-DOUBLE ASTEROID REDIRECTION TEST

SOURCE –INDIAN EXPRESS

CONTEXT

DART (Double Asteroid Redirection Test) spacecraft collided with the space rock Dimorphos .It deflected the trajectory of the pair of space rocks.

WHAT IS THE KICK METHOD

• Compared to the massive Dimorphos, DART is a tiny Goliath, crashing at a breakneck speed of 23,760 kilometers per hour, the momentum is adequate to slash the angular momentum of Dimorphos, making it speed up and move closer to Didymos.
• All of these reduce the orbital period and the time taken for the moonlet to go around the primary asteroid.
• The pair’s trajectory is thus deflected as the net result of these dynamics.
• The extent of trajectory change depends on the context
• Close-up images transmitted by the DART moments before the fatal collision indicate that Dimorphos is more like a pile of rubble loosely held by gravity, if true the impact will eject a cascade of debris, each piece carrying away a bit of momentum and energy.
• And as a net result, the asteroid will suffer a considerable loss.
• It will speed up more, and the orbit will become nearer to Didymos. The orbital period will then reduce by as much as 10 minutes.

AIM

• Save humanity from potential cataclysmic collision by safely deflecting a killer asteroid on its course toward earth.
• It could fuel space mining technologies and unleash the space economy

DART FEATURES

DRACO –Didymos Reconnaissance and Asteroid Camera for Optical navigation

• This is a camera to observe collisions and their consequences.

Light Italian CubeSat 

• This is for imaging asteroids.
• Hovering 50 kilometers from the asteroid, the two cameras aboard the CubeSat have captured the plume of debris ejected by the collision.

ASTEROIDS

• These are leftover materials from the formation of the sun, earth, and planets, through the accretion and agglomeration of giant gas and rocks scattered.
• Some of these cross their path and collide with earth from time to time, resulting in a spectacular meteor shower.
• Most of the rocks are so small that they burn up completely in the atmosphere due to frictional heating.

IMPACT

• If the asteroid is large enough, the charred piece falls through as a meteorite. The falling piece from a meteoroid 140metres wide or more will be capable of completely wiping out a city like Chennai.

RARE EARTH MINERALS

• Rare Earth elements-Yttrium ,niobium ,rhodium ,palladium ,osmium ,iridium and scandium
• For developing green energy technologies –electric vehicles, solar panels, wind turbines, and energy storage devices and ushering in the low carbon economy of the future rare earth elements are critical.
• But they are in short supply
• It is believed that asteroid mining could solve this problem.

POSSIBILITIES

• China is set to deflect a 40 m diameter earth crossing asteroid called 2020 PN1 sometime in 2026, while the drive comes from a desire to protect the earth from killer asteroids, perhaps the lure of space mining lurks behind.
• Mining rare earth elements come with a high environmental cost, in the coming years, the penalty for polluting could make space mining economically viable.
• The kick techniques that deflect asteroids can be used to move a small asteroid into a convenient position for space mining 
• NASA‘s Asteroid Redirect Mission (ARM) aimed at precisely this by bringing a 20-tonne space rock near earth to study and mine.