Asteroid 2000.QW7 passed at 3 millions km from Earth

Interview with Michael Martin-Smith, gatered by A. Autino

Dear Michael, I listened, by a minor tv news, that an asteroid 500 meters large, the name seems to me 2000.QW7, passed some days ago at 3.5 millions km from Earth. They said:

  1. If the asteroid came nearer could cause a very big disaster, even not impacting our planet.
  2. If the asteroid came on Earth, it could cause the death of 25% of humans.
  3. (listen!) though we have a proper international institution, named Spaceguard, properly dedicated to discover potentially dangerous incoming objects, the object was discovered only 6 days before the passage.

I think such news are offensive towards Spaceguard, and completely defective, as far as the main information: the news left to believe that it makes some difference if we acknowledge a possible impact six days or six months before, and that it was a guilty, by Spaceguard, to have given to the alarm only 6 days before! In truth, not having any means to defend us, it does not make a great difference. Moreover, the press gives of usual very insufficient relief to this kind of news, and so the governmental authorities: I would not be surprised if Spaceguard was trying to get the Institutions attention since some week! Moreover, creed that Spaceguard would be happiest for increasing the own efficiency, if it enjoyed better financings, as it should be perfectly reasonable to expect, by a species that had a real intention to survive in this Universe.

Thank you from your friend Adriano


Dear Adriano,

You are quite right, it is true that an asteroid was found a few weeks ago which passed 3.5 million kilometres away from Earth ( about 10 times as far as the Moon. It is estimated at about 400 metres in diameter, or about 5 times larger in diameter (125 times more volume) than the object which hit Tunguska in 1908.

  1. This object was thought to have been a cometary fragment from Comet Encke and exploded in the atmosphere like a hydrogen bomb, giving about 20 megatons TNT worth of energy 2000 square kilometres of Siberian forest were flattened and surely any city which would have been hit would have been ruined!
  2. Object 2000 QW7 would impact with an energy equivalent of about 1,200 megatons, or a major nuclear war It would only be dangerous for us IF it hit the Earth - on land or sea, but its orbit is such that it will have opportunities for close encounter every 19 years or so - but, so far, none is expected to actually hit us. The number of casualties from such an impact is hard to ascertain for sure, but if it hit an ocean( odds of 2 to 1) it would raise a tsunami of about 250-300 metres high at 1000 kilonmmetres away and 80 or so metres at 3000 kilometres away,. Thus in the Atlantic - for instance - many of the world's major cities would receive a wave 80 metres high; consider that the earthquake generated tsunami in Papua New Guinea 2 years ago was 10 metres high, and took 8,000 lives at least A continental impact would cause a regional disaster with the loss of perhaps tens of millions of lives and of course economic and social wreckage beyond counting. Our world is very tightly interlinked so the ramifications are very complicated.
  3. As for Spaceguard, the real criticism is that is still, after all the publicity, only a small but dedicated band of professionals with no real budget. Japan, China, and NASA , as well as Italy all have serious astronomers looking for asteroids, but there is as yet no international Government co-ordinated and funded programme specifically for Spaceguard; Australia indeed has a view of 33% of the night sky from the Southern Hemisphere but their leading watcher Duncan Steel has bee deprived of funds. NASA's stated goal is to locate 90% of 1 kilometre objects within 10 years- which still leaves rook for new comets many thousand objects of the size of 2000QW7 and a few dozen large objects. It is a major effort but still only a start.

This story illlustrates two things:

  1. That we are nowhere near, yet, knowing all the objects that can one day hit us.
  2. The Global Community, ie governments, have a long way to go in supporting and co-ordinating such work as Spaceguard has been doing.

It is good that there has been media criticism, since otherwise we could assume there was no public interest in self preservation at all; what the media have yet to learn however is to direct their attacks to the proper quarters! The public have yet to learn that our Destiny is not to be read in the charts of astroger fortune tellers, but to be actively built from the solid objects which threaten our future!

Ciao Michael

AA, MMS - TDF 3/2000 - 14/10/2000