[FPSPACE] Report of asteroid explosion over Indonesia earlier this month

[Peter Pesavento]

>From the Telegraph (UK):

 

http://www.telegraph.co.uk/science/space/6444895/Asteroid-explosion-over-Ind
onesia-raises-fears-about-Earths-defences.html

 


Asteroid explosion over Indonesia raises fears about Earth's defences


An asteroid that exploded in the Earth's atmosphere with the energy of three
Hiroshima bombs this month has reignited fears about our planet's defences
against space impacts.


By Tom Chivers
Published: 10:23AM GMT 27 Oct 2009

 

On 8 October, the rock crashed into the atmosphere above South Sulawesi,
Indonesia <http://www.telegraph.co.uk/news/worldnews/asia/indonesia> . The
blast was heard by monitoring stations 10,000 miles away, according to a
report by scientists at the University of Western Ontario
<http://neo.jpl.nasa.gov/news/news165.html> . 

Scientists are concerned that it was not spotted by any telescopes, and that
had it been larger it could have caused a disaster. 

The asteroid <http://www.telegraph.co.uk/science/space> , estimated to have
been around 10 metres (30ft) across, hit the atmosphere at an estimated
45,000mph. The sudden deceleration caused it to heat up rapidly and explode
with the force of 50,000 tons of TNT. 

Luckily, due to the height of the explosion - estimated at between 15 and 20
km (nine to 12 miles) above sea level - no damage was caused on the ground. 

However, if the object had been slightly larger - 20 to 30 metres (60 to
90ft) across - it could easily have caused extensive damage and loss of
life, say researchers. 

Very few objects smaller than 100 meters (300ft) across have been spotted
and catalogued by astronomers. 

Tim Spahr, director of the Minor Planet Center
<http://www.cfa.harvard.edu/iau/mpc.html>  in Cambridge, Massachusetts,
warned that it was inevitable that minor asteroids would go unnoticed. He
said: "If you want to find the smallest objects you have to build more,
larger telescopes. 

"A survey that finds all of the 20-metre objects will cost probably multiple
billions of dollars." 

The fireball was spotted by locals in Indonesia, and a YouTube video taken
that day <http://www.youtube.com/watch?v=yeQBzTkJNhs>  "appears to show a
large dust cloud consistent with a bright, daylight fireball", according to
the Ontario researchers. 

An asteroid or comet fragment around 60 meters across is believed to have
been behind the Tunguska Event <http://en.wikipedia.org/wiki/Tunguska_event>
, a powerful explosion that took place over Russia in 1908. The blast has
been estimated at equivalent to 10-15 million tons of TNT - enough to
destroy a large city. 

The White House
<http://www.telegraph.co.uk/news/worldnews/northamerica/usa/barackobama/>
is to develop a policy on the space object impact threat by October next
year. 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.friends-partners.org/pipermail/fpspace/attachments/20091027/3e6932db/attachment.html