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·!lit ' into rtteteot'tle
The wOrst effects l'ecOrded were on 15 Feb 2013
when a meteoroid exploded over Chelyabinsk
Oblast in the Urals in Russia. Around 1,200
people were injured, mostly from flying glass
caused by the shock wave following the fireball.
Astronomer Alan Harris has calculated that
the odds of being killed by an asteroid are 1 in
700,000. Scientists have suggested an asteroid
bigger than 10 km (6.2 mi) across would kill most
of humanity; fortunately, these only arrive once
every 100 million years.
Largest meteorites
• Overall: Hoba meteorite
-59 tonnes (130,000 lb),
found in 1920 at Hoba West
in Namibia.
• Exhibited in a museum:
Cape York meteorite -
30,883 kg (68,085 lb), found
in 1897 near Cape York in
the west of Greenland; now
at the Hayden Planetarium
in New York City, USA.
• From Mars: Zagami
meteorite - 18 kg (40 lb),
found on 3 Oct 1962 near
Zagami, Nigeria.
Largest tektite
Tektites are glassy pieces of
rock formed by the melting
and cooling of terrestrial
rocks after meteor impacts.
A tektite weighing 10.8 kg
(23 lb 13 oz) was discovered
in 1971 in Thailand.
-five times that of all
explosives used in
World War II. While
' ther.e are no eact
figures on record
from 1908, there are
acqurate measurements
of jhe·recent grelftest
measured impact
• on,Earth. This was the
· Cheabinsk impact of -
· 15 F"b 2013 (see above) .
.
.
Largest impact c;:rater
on Earth .
· T)le Vredefort crater, near
· Johannesburg in South
' Africa, may have lost the title
··of olaest impact crater
1o Greel)land's Maniitsoq
crater (see right), but it
remains the largest crater,
'lj(ith an estimated diameter
of around 300 km (186 mi).
The crater was formed by
an impact that occurred
about 2 billion years ago.
as the Maniitsoq crater, the structure Is around
100 km (62 mi) across. Much of it has eroded and
it may once have been much bigger. If such a
crater was formed in an impact with Earth today,
most life would be wiped out.
Crash trash: NASA litter fine
On 11 Jul 1979, the defunct US space station
Skylab (left) re-entered Earth's atmosphere
and disintegrated. Large chunks of the station
survived to crash in Western Australia, and
the Australian Shire of Esperance imposed a
AUS$400 (now £800) fine on NASA for littering,
which NASA didn't pay. The bill was finally settled
on their behalf in 2009 by US radio host Scott
Barley, who raised the money from his audience
for the 30th anniversary of Skylab's demise.
Pieces of Skylab are on display in Esperance's
museum, as is a poster declaring the fine paid.
Numerous space missions
have sought to return sample
material to Earth:
• Apollo (1 969-72): 2,415
samples of Moon rock
weighing a total of 382 kg
• Luna (1959-76): Soviet
robotic probe missions that
collected 326 g of lunar
samples
• Orbital Debris Collector on
Mir (1 996-97) brought back
interplanetary dust
• Genesis (2001 -04): NASA
project to collect solar wind
molecules (first material
collected beyond the Moon)
www.guinnessworldrecords.com 033