How to deflect an asteroid

Gareth Collins of Imperial College London’s Department of Earth Science & Engineering explains how to defeat near-Earth objects. Sorry, Bruce Willis.
Find the threat “Near-Earth objects are pieces of rock or ice in the solar system whose orbit occasionally brings them close to Earth,” says Collins. Their small size and distance from Earth make them difficult to see, but telescope arrays have detected 85 per cent of objects more than 1km in diameter. “Thousands reach the Earth every year, but hazards are infrequent. The ten-kilotonne object over Chelyabinsk in February was a once-a-century event.”
Assess the risk The damage that an asteroid impact can cause depends on factors such as its size, speed, density and where it lands. Collins has developed a website (impact.ese.ic.ac.uk) to help estimate threats. “Asteroids about 1.5km in diameter are believed to be large enough to disperse debris worldwide,” he says. “The impact of an object the size of a city block would not cause global damage, but could have far-reaching consequences if it occurred in an ocean off a populous place.”
Deflect it Whether or not a deflection mission is possible depends on the asteroid’s size and how much warning there is. “With more than ten years’ warning, one of a number of strategies could be used to knock it off course,” Collins says. Colliding a spacecraft with the asteroid is the most practical and could be used on asteroids up to a few hundred meters across; adding a nuclear warhead would be better for objects up to 1km across. Or use a spacecraft as a “gravity tractor” to pull the object away from Earth.


Image credit: Tavis Coburn

How to deflect an asteroid

Gareth Collins of Imperial College London’s Department of Earth Science & Engineering explains how to defeat near-Earth objects. Sorry, Bruce Willis.

Find the threat
“Near-Earth objects are pieces of rock or ice in the solar system whose orbit occasionally brings them close to Earth,” says Collins. Their small size and distance from Earth make them difficult to see, but telescope arrays have detected 85 per cent of objects more than 1km in diameter. “Thousands reach the Earth every year, but hazards are infrequent. The ten-kilotonne object over Chelyabinsk in February was a once-a-century event.”

Assess the risk
The damage that an asteroid impact can cause depends on factors such as its size, speed, density and where it lands. Collins has developed a website (impact.ese.ic.ac.uk) to help estimate threats. “Asteroids about 1.5km in diameter are believed to be large enough to disperse debris worldwide,” he says. “The impact of an object the size of a city block would not cause global damage, but could have far-reaching consequences if it occurred in an ocean off a populous place.”

Deflect it
Whether or not a deflection mission is possible depends on the asteroid’s size and how much warning there is. “With more than ten years’ warning, one of a number of strategies could be used to knock it off course,” Collins says. Colliding a spacecraft with the asteroid is the most practical and could be used on asteroids up to a few hundred meters across; adding a nuclear warhead would be better for objects up to 1km across. Or use a spacecraft as a “gravity tractor” to pull the object away from Earth.

Image credit: Tavis Coburn


Posted 1 year ago with 252 notes
Tagged:Astronomyspaceasteroidearthnear earth objectsspacecraftscience

  1. cultivando-ampolletas reblogged this from xyaeger
  2. xyaeger reblogged this from spaceplasma
  3. saddlelite reblogged this from spaceplasma
  4. colourfader reblogged this from saddlelite
  5. stuckinmayhead reblogged this from dreamsrecurring
  6. dalek-survivor reblogged this from dreamsrecurring
  7. dreamsrecurring reblogged this from emmajerk
  8. therationalrobin reblogged this from spaceplasma
  9. vanesa reblogged this from we-are-star-stuff
  10. staynifty reblogged this from empyr3an
  11. financial--panther reblogged this from we-are-star-stuff
  12. mantic-misfit reblogged this from godblessvodka
  13. alldroneup reblogged this from empyr3an
  14. journeyofhumanity reblogged this from thenewenlightenmentage
  15. je-mappelle-doc reblogged this from thenewenlightenmentage
  16. holy-shit-8 reblogged this from thenewenlightenmentage
  17. toh-ska reblogged this from thenewenlightenmentage
  18. dante515 reblogged this from thenewenlightenmentage
  19. miracleman701 reblogged this from thenewenlightenmentage
  20. sighs-of-the-night reblogged this from thenewenlightenmentage
  21. stand1701 reblogged this from thenewenlightenmentage
  22. thenewenlightenmentage reblogged this from sagansense
  23. antipodian reblogged this from sagansense