icy. That's because ice in the early solar system is thought to have
ice on its surface.
The team found the water signal by measuring the spectrum of infrared light radiated by the object.
, a second team has found the water ice signature using the same telescope, NASA's Infrared Telescope Facility in Hawaii.
That is surprising, since the asteroid's distance from the sun means it should lose about 1 metre of ice each year.
"This ice is unstable, and therefore we need a process to explain why there is ice on the surface now," said Campins.
One possibility is that an icy object might have collided with 24 Themis, leaving behind a layer of ice.
Two polar scientists hot on the trail of an arctic mystery have a new
tool for exploration: a hovercraft, specially outfitted for week-long
trips over the ice with scientific instruments and solar panels.
© Hall and Kristofferson The hovercraft
Their
quarry is a nearly 22,000 square-mile patch of disturbed Arctic sea
floor that could be evidence of a massive asteroid strike. John Hall, a
now-retired geoscientist, discovered the anomaly during his late-'60s
graduate work aboard Fletcher's Ice Island, a huge berg U.S. scientists
inhabited for several decades.
Since then, no scientific vessel has been back over the area
to collect more data. The massive icebreakers that have crunched
through the Arctic since the 1990s can't reach the spot, said Yngve
Kristofferson, a scientist and explorer at the University of Bergen in
Norway.
Kristofferson became intrigued with Hall's data and in 2004,
the two of them met in Bergen to talk Arctic science from eight in the
morning to 10 in the evening. At the end of their time together, they
came to a decision: They needed a hovercraft.
Luckily, Hall is a partial heir to the fortune his
grandfather made as head of the American Chicle Company, the trust that
ran the American bubble gum game early in the 20th century, so he was
able to buy the vehicle with private funds. A customized Griffon
Hovercraft 2000TD, it is now going through the paces, hitting the
Arctic from its home at Longyearbyen for the first time in 2008, and
hoping to reach its full potential next spring.
Hall delivered a speech detailing the craft's capabilities and
mission at Columbia University's Lamont Doherty Earth Observatory on
Oct. 6.
"The neat thing with a hovercraft is that you drive with the
same ease over 10 centimeter-thick ice as you do with five meter thick
ice," Kristofferson told Wired.com.
Despite their futuristic reputation, hovercraft have been
commercially available for decades. The concept is actually quite
simple. A big engine or turbine pumps air into a rubber skirt that
allows the vehicle to tread lightly on whatever it's touching. The R/H
Sabvabaa, for example, weighs six tons but exerts no more pressure on
any patch of ice than a seagull standing on one leg would by standing
on it. The rest of the power from the engine is devoted to propulsion,
allowing the craft to skip along at speeds up to 50 miles per hour.
For the strange terrain of the Arctic, it works perfectly, Hall and Kristofferson wrote in an article in the journal
The Leading Edge in August.
"The craft has proved to be useful for a variety of scientific
tasks," they wrote. "It appears more efficient than any other platform
for ice-thickness measurements and oceanographic work."
Their hovercraft push comes as money has flooded into Arctic
research. With Arctic ice melting, the nations adjacent to the ocean
are rushing to stake their claims not just on the water, but on the oil
and natural gas that lie under the sea floor, leading to calls to
establish a National Park to protect the area.
The most fascinating target for the hovercraft is the area of
very thick ice closer to Ellesmere Island and northern Greenland. Not
even nuclear-powered icebreakers have ventured into the region. It was
just Hall's good fortune to have been aboard the floating ice island
doing research when it passed near this apparent sea floor anomaly. The
duo, along with several other colleagues, described the discovery in a
2008 paper in the
Norwegian Journal of Geology .
© Hall and Kristofferson Fletcher’s Ice Island Camp
"The
upper couple hundred meters of sediment at the bottom of the Arctic
Ocean is just like a carpet that is draped over the topography except
for these areas where 150 meters are just blown away and the seabed is
severely deformed," Kristofferson said.
To Kristofferson and Hall, the evidence suggests that a
pressure wave caused by a pieces of a large asteroid crashing into the
Arctic Ocean created these strange features.
"Our working hypothesis is that the spectrum and scale of the
observed disturbances are best explained as the effect of a shock wave
generated by the impact of an extraterrestrial object," they wrote.
But the hypothesis remains just that without more data. The
hovercraft works well, but with its on-board fuel, its range is limited
to around 500 miles. For that reason, the scientists imagine they'll
use a larger vessel as a base of operations.
"What we really want to do is go along with an icebreaker into
the Arctic. You can greatly enhance the scientific output if you have a
hovercraft. If you have more of them, even better," Kristofferson said.
"We can go out and do our own science and be away for many days. If the
icebreaker gets stuck, we're not stuck."
Still, both Hall and Kristofferson know they face an uphill
battle to get other scientists to take both the hovercraft and asteroid
impact ideas seriously.
"The task is to figure out the real message in the data - the
dream challenge for any scientist," Kristofferson told the Lamont
Doherty alumni magazine earlier this year. "So far, we have mostly met
shaking heads, which just makes it more fun."
© NU.nl/Robert Mikaelyan
Hundreds of people report seeing a spectacular fireball or meteorite over the Netherlands in Tuesday's clear evening skies.
The police emergency number, Dutch coastguard and KNMI weather bureau
report dozens of phone calls about the meteorite, which was seen in
Germany and Belgium.
'I was standing in front of my window when there was a bright
flash of light and a white fireball in the sky fell apart into three
smaller ones,' eyewitness Erik Alberts from Zuidbroek in Groningen
province told Nos tv. 'Like fireworks. A few seconds later, perhaps
half a minute, there was a low rumble and the windows shook.'
© University of Western Ontario A
Space
rocks formed when the solar system was created billions of years ago
are believed to have fallen to Earth near Grimsby in a fiery light show
two weeks ago.
Astronomers will be digging through farmers' fields Thursday
and Friday on the hunt for hunks of a meteor that blazed across the
skies of southern Ontario Sept. 25 shortly after 9 p.m.
The beachball-sized meteor was first picked up by cameras
operated by the University of Western Ontario's physics and astronomy
department 100 kilometres above Guelph as the fireball streaked
southeastward at a speed of about 75,000 km/h.
Astronomers at the university have traced the meteor's path
and believe chunks of it may have landed above the escarpment within a
10-km radius of Grimsby.
"We're pretty certain something came down," said Phil
McCausland, a postdoctoral fellow with the university's astronomy
department.
"It's hard to put an X on the map and say, 'There,'
because what happens is at the end of the fireball path the lights go
out. There's no camera record of that."
It's likely small pieces of the meteor - anywhere between the
size of a golf ball or a fist - made it through the atmosphere and hit
the ground, he said.
"It could be dozens, it could be one or two. It's hard to say,
but if it's one or two, they will be on the largish size - probably
more than a kilogram."
Researchers are keen to find any of the meteorites because
it's extremely rare to have their fall to Earth documented so well with
photo evidence.
Based on all of the information already known about the rocks,
it's possible for astronomers to determine which orbit they came from
and learn more about the early history of the solar system.
"There's only a handful, perhaps a dozen, meteorites that have this kind of orbital information," McCausland said.
The rural area where the meteorites are believed to have landed is largely farmland with some forest.
McCausland has already spent several days over the past week searching for the rocks and interviewing landowners in the area.
He was expected to be back on the hunt again Thursday with other researchers.
"Even though the (cameras) we have narrows it down quite
nicely, it's still a large area to search. We're still talking about 12
to 16 kilometres," he said.
Doug Welch, an astrophysicist at McMaster University, will be joining the search.
Welch monitors one of Western's meteor-seeking sky cameras at the Hamilton university.
The fireball that torched across the sky two weeks ago practically went directly overhead of the Hamilton camera.
"It's really spectacular. ... I've seen them live, but
it's very rare for them to be this bright," he said.
Recovering meteorites that may have fallen gives researchers a
rare opportunity to learn more about the formation of the solar system,
he said.
"These are free samples from elsewhere in the solar system
delivered to your door. We have sample-return missions that cost
hundreds of millions of dollars."
Meteorologist and Grimsby resident Kerry-Ann Lecky Hepburn spends much of her spare time photographing the stars and planets.
But the night the fireball streaked towards Grimsby, she didn't
have her camera trained on the sky. She was watching TV with her
meteorologist husband in their home atop the escarpment.
"We saw a bright flash and thought, 'How can it be a thunderstorm. There shouldn't be any storms around.'"
A quick check online the following morning confirmed for Lecky Hepburn the bright light was a meteor.
"It would have been nice to see something other than just the bright flash," she said.
Researchers are calling for anyone who has found pieces of
meteorite to contact them, as well as people in the area who witnessed
the fireball.
Meteorites are typically dark, smooth on the surface, heavier
than rocks of a similar size and able to attract magnets because of the
metals they contain.
Under Canadian law, meteorites become the property of whoever owns the property where they are recovered.
Photos and video footage of the meteor can be found
online .
The Grimsby space rock has been found.
A fragment of meteorite the size of a golf ball smashed in the
windshield of a Grimsby family's sport utility vehicle on Sept. 25,
according to a media release from the University of Western Ontario.
Astronomers released a video Oct. 7 of a blinding
meteor streaking across the skies of Southern Ontario three weeks ago,
estimating pieces may have landed in Grimsby or West Lincoln.
Meteorite hunters have been scouring the area ever since.
A press conference to discuss the find is scheduled for Friday morning.
Scientists think a fireball that flew over New Mexico may have been close enough to actually hit the ground.
A Santa Fe astronomer was able to catch the fiery streak on video.
Thomas Ashcraft says the fireball didn't disintegrate when it hit the
atmosphere. It may have landed somewhere near Taos.
"If we can get other camera angles, than we can put all the positions
together and possibly hunt for an important--scientifically
important--meteorite," he said.
The event was also captured by cameras at Sandia National
Labs. Scientists estimate the meteor was about the size of a basketball
all the way up to that of a small car.
Scientists at Sandia think it disintegrated over Chaco Canyon.
A mysterious basin off the coast of India could be the largest,
multi-ringed impact crater the world has ever seen. And if a new study
is right, it may have been responsible for killing the dinosaurs off 65
million years ago.
© Geological Society Of America Three-dimensional
Sankar
Chatterjee of Texas Tech University and a team of researchers took a
close look at the massive Shiva basin, a submerged depression west of
India that is intensely mined for its oil and gas resources. Some
complex craters are among the most productive hydrocarbon sites on the
planet. Chatterjee will present his research at this month's Annual
Meeting of the Geological Society of America in Portland, Oregon.
"If we are right, this is the largest crater known on our
planet," Chatterjee said. "A bolide of this size, perhaps 40 kilometers
(25 miles) in diameter creates its own tectonics."
By contrast, the object that struck the Yucatan Peninsula, and
is commonly thought to have killed the dinosaurs was between 8 and 10
kilometers (5 and 6.2 miles) wide.
It's hard to imagine such a cataclysm. But if the team
is right, the Shiva impact vaporized Earth's crust at the point of
collision, leaving nothing but ultra-hot mantle material to well up in
its place. It is likely that the impact enhanced the nearby Deccan
Traps volcanic eruptions that covered much of western India. What's
more, the impact broke the Seychelles islands off of the Indian
tectonic plate, and sent them drifting toward Africa.
The geological evidence is dramatic. Shiva's outer rim forms a
rough, faulted ring some 500 kilometers in diameter, encircling the
central peak, known as the Bombay High, which would be 3 miles tall
from the ocean floor (about the height of Mount McKinley). Most of the
crater lies submerged on India's continental shelf, but where it does
come ashore it is marked by tall cliffs, active faults and hot springs.
The impact appears to have sheared or destroyed much of the
30-mile-thick granite layer in the western coast of India.
The team hopes to go India later this year to examine rocks
drill from the center of the putative crater for clues that would prove
the strange basin was formed by a gigantic impact.
"Rocks from the bottom of the crater will tell us the telltale
sign of the impact event from shattered and melted target rocks. And we
want to see if there are breccias, shocked quartz, and an iridium
anomaly," Chatterjee said. Asteroids are rich in iridium, and such
anomalies are thought of as the fingerprint of an impact.
NASA's intrepid Mars rover Opportunity has found yet another meteorite on the surface of the red planet.
Opportunity stumbled upon this new meteorite, dubbed "Shelter Island,"
less than three weeks after driving away from a larger meteorite that
the rover examined for six weeks.
The rover began its approach to the meteorite with a 92-foot
(28-meter) backwards drive on Oct. 1, the rover's 2,022nd day on Mars.
Opportunity and its twin rover Spirit - which is currently
embedded in a soft spot of soil called Troy - have been on the Martian
surface for more than five years.
Shelter Island is a pitted rock is about 18.5 inches
(47 cm) long. The meteorite was first detected in images taken two
Martian days earlier. (A Martian day is 24 hours and 40 minutes long.)
Two Martian days after its backward drive, Opportunity turned
around to face the meteorite. In the days that followed, it made a
final 3.3-foot (1-meter) move to put the rock within reach of the rover
robotic arm . Mission managers are now planning to use the arm to
contact the meteorite and make measurements.
Opportunity has driven about 2,300 feet (700 meters) since it
finished studying the meteorite called "Block Island" on Sept. 11,
2009.
Block Island weighs at least half a ton, is composed of iron
and nickel, and is likely too large to have plunged through the current
thin atmosphere of Mars without being obliterated upon impact,
scientists say.
Both meteorites have been found during Opportunity's trek to its next target, Endeavour Crater.
Opportunity also found a third meteorite, Heat Shield Rock, in 2004.
Comment: You can read a report of this sighting
here
© Mail News and Media LTD Experts believe the 4lb dark grey object had been orbiting Earth for at least a decade
Pensioner
Peter Welton was amazed when a piece of red-hot debris crashed through
his roof in July. Now experts have confirmed the object had travelled
hundreds of miles from outer space.
The 75-year-old had been in his bedroom when he heard a smash
and found the football-sized lump of extra terrestrial debris in the
loft of his home in Hull.
The great-grandfather said: 'It was a hell of a shock. If it
had landed in the street and hit anybody it would have killed them.'
As it was too hot to handle he brought it downstairs using oven gloves.
The 4lb dark grey object was removed by Humberside Police before being taken away by the Ministry of Defence for investigation.
Mr Welton and wife Mair, 62, then received a phone call from the RAF, who said the metal mass was
most likely to be space junk.
This could mean anything from part of a spacecraft to a piece of abandoned satellite.
RAF spokesman Squadron Leader Jeff Brock confirmed the finding, which
was the first the RAF's Defence Flying Complaints Investigation Team
had encountered.
© Mail News and Media LTD Peter Welton, 76, was in his home is Hull when the space debris slammed into his loft
He
said: 'Following consultations with the European Space Agency and Nasa,
we are confident the object is more than likely space debris which was
orbiting in excess of a decade.
'This is the first bit of space debris that we have got our
hands on - we have never until this occasion had anything relating to
it at all.'
The DFCIT, based in Henlow, in Bedfordshire, investigates
complaints related to military flying. Experts initially thought the
object may have come from an aircraft.
However, its size and appearance was found to be 'entirely
consistent' with space junk, and its heavy mass meant it was more
likely to have been in a state of decaying orbit for a decade or more.
Russia (then the Soviet Union) put the first object into space
just 51 years ago - Sputnik One. Since then we have created a swarm of
perhaps tens of millions of items of space junk. The debris ranges in
size from paint flecks to defunct satellites.
The oldest piece of space junk still circling is the Vanguard
1 communications satellite that was launched by the U.S in 1958, but
stopped working in 1964.
Most hug close to the surface, 200-300 miles up in
low-earth-orbit, where they are a hazard to telescopes and the
astronauts on the International Space Station.
© Mail News and Media LTD The 4lb piece of debris fell to Earth and landed in West Hull
Most
debris will eventually burn up in the atmosphere, but larger objects
can reach the ground intact. Most have come down over the Pacific Ocean
or sparsely populated areas.
There has only been one recorded incident of a person being
hit by human-made space debris. In 1997, Lottie Williams from Oklahoma
was hit in the shoulder by a 5.1" piece of blackened metal. It was
later confirmed to be part of the a rocket fuel tank launched the year
before. Luckily she was not injured.
Despite narrowly escaping being hit, Mrs Mair said she was excited to hear the experts' findings.
'I think it's wonderful,' she said.
Mail's online video report on the event
Scientists say a golf ball-sized rock that smashed through the
windshield of an SUV is a meteorite, possibly from a spectacular
fireball that streaked across the sky above Hamilton three weeks ago.
University of Western Ontario researchers confirmed the rock was a meteorite. It will be unveiled today at a media conference.
The fireball was captured on video Sept. 25 by a network of
cameras administered by Western that regularly watch the skies at
night. One of the cameras is located at McMaster University.
For the past two weeks, a search team headed by Phil
McCausland, a postdoctoral fellow at Western's Centre for Planetary
Science and Exploration, has been scouring the Grimsby area after
working out mathematical models that suggest the fireball crashed
there.
McCausland believes there are other meteorites on the ground
that have yet to be found because the meteor weighed as much as a tonne
when it hit Earth's atmosphere.
He returned to Grimsby yesterday with a search team of a few
people looking around the residential area where the meteorite was
discovered by a Grimsby resident.
"It was a very unusual rock, so the finder just held onto it,"
McCausland said. "They began to think it was a meteorite after the
media coverage happened."
He would not be specific about where the rock was located,
only that it was "just barely" within the 12-square-kilometre area
south of the town of Grimsby that searchers were focusing on.
Tests are being done to try to find out more about the 50-gram object.
The discovery, he said, has buoyed enthusiasm that other pieces
will be found and it will turn out to be a major find for the astronomy
community.
Meteorites are relatively common, but it is highly unusual to find one from a meteor videotaped coming through the atmosphere.
"You don't stop when you find one piece. You keep going," said
McCausland. "Finding one is confirmation that something came down here
and there are probably many others."
They are looking intensively in the area of the first find
because "meteorites don't care where they land. They could hit a house,
a roof. They can end up anywhere."
mmcneil@thespec.com
905-526-4687
Washington - Reports indicate that hundreds of people in the
Netherlands and Germany have reported seeing a huge exploding fireball
in the sky on October 13.
According to a report in
National Geographic News , amateur photographer Robert Mikaelyan captured the phenomenon on camera.
Mikaelyan managed to capture several shots of the fireball as
it swung low over the northern city of Groningen, Netherlands, and
began to break apart into smaller chunks.
"I suddenly saw a light in the sky coming fast and quickly got the pictures taken," Mikaelyan said.
A few seconds after the fireball had been sighted, witnesses heard a
sonic boom followed by low rumbles that rattled windows-signatures of a
high-altitude explosion.
The object was most likely a rogue space rock that
disintegrated shortly after hitting Earth's atmosphere, according to
experts, who speculate that pieces of the meteor may have landed in the
North Sea.
"Indeed it was a huge event," said Theo Jurriens, of the Kapteyn Astronomical Institute at the University of Groningen.
Earth is constantly being bombarded by smaller debris from comets, asteroids, and even other rocky planets in the solar system.
But a fireball of this size and brightness is likely seen anywhere in the world only every 20 to 25 years , according to Jurriens.
Comment: Every 20-25 years? Somebody's not been paying attention. These are from the past 3 weeks:
October 9th : Caught on camera: Meteorite streaks across New Mexico sky
October 5th : Video: Fireball lights up sky over Iceland
Septmber 28th : Cosmic shock and awe: Fireball explodes over Argentina
September 25th : Spectacular Fireball filmed over Canada
Kaohsiung - An amateur astronomer who discovered an asteroid earlier
this year presented a model of his new discovery to Kaohsiung Mayor
Chen Chu Monday to share it with all residents of the southern Taiwan
port city.
Tsai Yuan-sheng discovered the asteroid along with an
assistant at the Lulin Observatory on Yushan, also known as Jade
Mountain, March 20 and tentatively named it "Kaohsiung" after his
hometown.
In August, the International Astronomical Union's
Committee on Small Body Nomenclature (IAU's CSBN) -- an international
organization responsible for the naming of asteroids and comets --
formally approved the designation and gave Tsai's discovery a permanent
number "215080." It was the first asteroid discovered by an amateur
Taiwanese astronomy buff to have won international recognition.
The asteroid, located between Mars and Jupiter, is similar in
size to Kaohsiung International Airport. At perihelion, the closest
point to the sun in its orbit, the asteroid is 350 million kilometers
from the sun and at aphelion, its most distant point from the sun in
its orbit, it is about 450 million kilometers from the sun.
It takes about four years for the newly identified asteroid to complete its orbit around the sun.
Tsai and Lin Chi-sheng, an astronomical observation assistant
at Lulin Observatory, spotted the asteroid using highly advanced
digital equipment.
Tsai recalled that he first detected that the body could both
rotate around its own axis and circle the Sun and that its position
coordinates varied each day.
"I then took photos of the object consecutively for analytical
comparison and finally came to the conclusion that it was an asteroid
that had never been documented before," Tsai recalled.
According to Tsai, most larger asteroids have been discovered
and only small asteroids that cannot be detected with the naked eye are
still left to be spotted with highly sophisticated instruments.
Tsai, 40, began to develop his interest in observing the stars
while studying at a military preparatory school as a teenager. At the
time, he was required to stand guard at night, and the long hours with
nothing to do led him to fall in love with stargazing.
He later dropped out of the naval academy to pursue his hobby
more freely. He now often takes his wife and children high into the
mountains to observe the stars at night.
Tsai has documented 13 asteroids, but "Kaohsiung" is the only one to have been recognized by the IAU's CSBN.
"I was so jubilant to obtain international recognition of my
latest discovery and thus decided to name it 'Kaohsiung' to honor my
beloved homeland," Tsai said.
"I also want to share my happiness in discovering the new body
with all fellow Kaohsiung residents, " Tsai said at the asteroid model
presentation ceremony at the city's Gangho Elementary School.
For her part, Mayor Chen said the discovery of the asteroid
and its designation as "Kaohsiung" are not only the "pride of
Kaohsiung" but also the "pride of Taiwan." Noting that Tsai's
achievement has inspired a "star chasing" fad in the city, Chen said
the city government will step up efforts to promote astronomical
education and cultivate more talent in the field.
Chen said she has directed the city's Bureau of Education to
allocate NT$1 million (US$31,056) annually to help finance the
operations of the Gangho Elementary School's astronomy observatory.
She also proposed that an astronomy-themed science park be
established after Kaohsiung City and Kaohsiung County merge next year.
Tsai Ching-hua, director of the municipal education bureau,
said the discovery of the asteroid has set a good model for the city's
astronomy education and pledged to study the feasibility of setting up
an astronomy theme park in the new Kaohsiung municipality.
© Jefferson Teng
The
Orionid meteor shower is underway. Earth is passing through a stream of
dusty debris from Halley's Comet, and this is causing meteors to shoot
out of the constellation Orion. Earlier today, amateur astronomer
Jefferson Teng photographed an Orionid fireball over Shanghai, China.
"I woke up early in the morning to observe the shower through
my bedroom window," says Teng. "This one was quite bright considering
the light pollution in Shanghai."
Forecasters expect the shower to peak on Wednesday, Oct. 21st,
with dozens of meteors per hour. The best time to look is during the
dark hours before sunrise. For best results, get away from city lights,
but as Teng discovered, country darkness is not absolutely necessary.
© Unknown
Investigators Say Radiation Levels Normal
Scientists were investigating Monday whether a large crater found in a
meadow in northern Latvia had been created by meteorite. One expert
said it was likely a hoax.
Experts in the Baltic country rushed to the site after reports
that a metorite-like object had crashed late Sunday in the Mazsalaca
region near the Estonian border.
Uldis Nulle, a scientist at the Latvian Environment, Geology
and Meteorology Center, said his first impression after observing the
site late Sunday was that the 27-foot (nine-meter) wide and nine foot
(three-meter) deep crater had been caused by a meteorite. He said there
was smoke coming out of the hole when he arrived.
© Unknown
However,
Dainis Ozols, a nature conservationist who examined the hole in
daylight on Monday, said it appeared to be a hoax. Ozols said he
believes someone dug the hole and tried to make it look like a
meteorite crater by burning some pyrotechnic compound at the bottom. He
added he would analyze some samples taken from the site.
When asked about Ozols' theory, Nulle refused to comment, saying he needed more time to make tests at the site.
Inga Vetere of the Fire and Rescue Service said they received a
call about the alleged meteorite on Sunday evening from an eyewitness.
She said a military unit was dispatched to the site and found that
radiation levels were normal. There were no injures.
Experts outside Latvia said it would be unusual for such a
In 2007, a meteorite crashed near Lake Titicaca in Peru, causing a
crater about 40 feet (12 meters) wide and 15 feet (five meters) deep.
© Unknown
Asta
Pellinen-Wannberg, a meteorite expert at the Swedish Institute of Space
Research, said she didn't know the details of the Latvian incident, but
that a rock would have to be at least three feet (one meter) in
diameter to create a hole that size.
Henning Haack, a lecturer at Copenhagen University's
Geological Museum said more information was needed to confirm that the
crater was indeed caused by a meteorite.
"With all these kind of reports we get there always is a pretty large margin of error," he said.
A fiery object struck farmland creating a large crater near a small town in northern Latvia.
No-one was injured in the incident and geologists are now studying the object, which may be a meteorite.
Locals claimed the object fell near a farmhouse on the outskirts of Mazsalaca town in the district of Valmiera last night.
It created a crater which measured 50 feet across and 16 feet deep.
A witness who claimed to have seen the incident described the
'meteorite' as making a noise similar to the one of an aircraft flying
at a low altitude.
ldis Nulle, a scientist at the Latvian Environment, Geology
and Meteorology Center, said there was smoke coming out of the crater
when he arrived at the crash site late Sunday in the Mazsalaca region
near the Estonian border.
'My first impression is that, yes, it was a meteorite,' he
said. 'All the evidence suggests this when compared to pictures of real
meteorite craters.'
© Reuters
He
said the rim of the crater was slightly raised and there was a
black-grayish scar at the bottom - both signs of a meteorite impact.
Experts outside Latvia said it was unusual for such a large
In 2007, a meteorite crashed near Lake Titicaca in Peru, causing a
crater about 40 feet (12 metres) wide and 15 feet (5 metres) deep.
Asta Pellinen-Wannberg, a meteorite expert at the Swedish
Institute of Space Research, said she didn't know the details of the
Latvian incident, but that a rock would have to be at least three feet
(one metre) in diameter to create a hole that size.
Henning Haack, a lecturer at Copenhagen University's
Geological Museum said more information was needed to confirm that the
crater was indeed caused by a meteorite.
© Unknown
'With all these kind of reports we get there always is a pretty large margin of error,' he said.
In Latvia, Nulle said a group of experts would examine the
crater today and bring rock samples back to the capital, Riga, for
testing.
Nulle rushed to the site after people in the area reported seeing a fiery object falling from the sky.
Inga Vetere of the Fire and Rescue Service said a military unit
has tested the site and found that radiation levels are normal. There
were no injures.
She said police have cordoned off the area to prevent souvenir hunters from taking away the soil.
'We are not finally sure that this is a meteorite,' she told
Itar-Tass news agency. 'Eyewitnesses said something fell from the sky
and fire started.'
Russian blogs posted YouTube video that claimed to show the
remains of the meteor burning brightly shortly after the crash, but the
validity of the video has not yet been confirmed.
© AFP/Getty Images
© Unknown
No one was injured after a meteorite fell near a small town in northern Latvia on Sunday, local Latvian media reported.
According to media reports, the meteorite fell near a residential house
on the outskirts of Mazsalaca town in the Valmiera district of Latvia,
leaving a crater of some 20 meters (66 feet) in diameter and 10 meters
(33 feet) deep.
A spokesperson for the Latvian State Fire and Rescue Service
said that rescuers and soldiers immediately cordoned off the territory,
however, it is still not clear whether it was an asteroid or a space
satellite.
"The territory has been immediately cordoned off as we still
do not know what fell down from the sky. According to preliminary
information, it was a meteorite. However, it is possible that it was a
[space] satellite or its fragment. A radioactive contamination is also
possible," she said.
A witness, who saw the object falling from the sky and leaving
a burning trace behind, said it was making a noise similar to the one
of an aircraft flying at a low altitude.
On March 2 this year, a 35-meter asteroid came within
72,000 kilometers of Earth. The size of the space rock was comparable
to the asteroid that caused the Tunguska disaster, but there was no
danger of a collision.
On June 30, 1908, an explosion equivalent to between 5 and 30
megatons of TNT occurred near the Podkamennaya Tunguska River in a
remote region of Russia's Siberia.
The Tunguska blast flattened 80 million trees, destroying an area of around 2,150 sq km (830 sq miles).
It is assumed that a huge meteorite had hit the area, although research expeditions failed to find an obvious crater.
Comment: Update: This incident appears to have been staged
'Meteorite' that landed in Latvia is a hoax, experts say
It was the student prank that apparently fell to earth after experts
dismissed a meteorite crash in Latvia as an elaborate hoax today.
Dramatic video of a fireball at the bottom of an impact crater
on farmland outside the town of Mazsalaca was shown all over the world,
taken by a group of film students who said that they had heard the
meteor strike.
But experts who examined the scene were less star-struck. Dr
Ilgonis Vilks, chairman of the scientific council at the University of
Latvia's Institute of Astronomy, said: "It's a fake. It's very
disappointing, I was full of hope coming here, but I am certain it is
not a meteorite."
Setting aside the astronomical odds of a group of film
students happening to be at the ready when a meteorite hits the Earth,
Dr Vilks said that several other tell-tale signs had given the game
away.
There was green grass inside the crater despite the
intense heat supposedly generated by the meteorite. The impact crater,
initially reported as 10 metres deep, was actually only 3 metres
including a lip of soil a metre high around the hole.
Dr Vilks said that there was neither ejected material from the
hole nor any fragments of meteorite on the surrounding land. Finally,
there was the flaming "meteorite" itself.
"It's a ball of clay that was burning. We took some samples
from it and geologists from the university will examine it," Dr Vilks
said. "There was a small blast heard by local people but this was not
strong enough to create the crater and there's only a small area in the
hole that is burnt."
Dainis Ozols, a nature conservationist who also examined the
scene, said that he believed somebody had dug the hole and burnt a
pyrotechnic compound at the bottom to make it appear like a meteorite
crater.
The alert was first raised on Sunday evening by Ancis
Steinbergs, who said that he had been out filming for a university
project with his girlfriend and a fellow undergraduate. He was refusing
to answer his telephone tonight to answer questions about the experts'
assessments.
He had earlier told
The Times that the trio had
heard a loud roaring sound "like an airplane falling from the sky"
seconds before the alleged meteorite hit the field behind some trees.
Mr Steinbergs said: "We saw something burning in the sky like
a ball and it was moving very fast and then there was a loud noise. We
went to find it and there was this big hole with fire burning in it.
"It was so hot that the camera was misting up. We thought it was really dangerous because there might be an explosion."
Video taken by the group showed them approaching the lip of the
crater and filming the glowing hot "meteor" at the bottom as they
talked excitedly among themselves. The clip bears similarities in style
to the
Blair Witch Project , a 1999 film based on supposedly "amateur" footage shot by three missing film students.
Mr Steinbergs said that he called Latvia's Fire and Rescue Service.
Inga Vetere, a spokeswoman, said that fire crews had attended the site
and cordoned it off. Tests had recorded normal levels of radiation and
nobody had been hurt.
Local news agencies reported that the landowner, Larisa
Gerasimova, had been quick to capitalise on interest surrounding the
crater and had begun to charge curious visitors $2 to view the site.
Earth is bombarded by thousands of small celestial objects
every year but most burn up in the atmosphere before they reach the
surface. The last recorded meteorite strike on land was in 2007 near
Lake Titicaca in Peru, when it left a crater 12 metres wide (40ft) and
five metres deep (15ft).
As the US government ponders a strategy to deal with threatening
asteroids, a dramatic explosion over Indonesia has underscored
how blind we still are to hurtling space rocks.
On 8 October an asteroid detonated high in the atmosphere above South
Sulawesi, Indonesia, releasing about as much energy as 50,000 tons of
TNT, according to a NASA estimate released on Friday. That's about
three times more powerful than the atomic bomb that levelled Hiroshima,
making it one of the largest asteroid explosions ever observed.
However, the blast caused no damage on the ground because of
the high altitude, 15 to 20 kilometres above Earth's surface, says
astronomer Peter Brown of the University of Western Ontario (UWO),
Canada.
Brown and Elizabeth Silber, also of UWO, estimated the
explosion energy from infrasound waves that rippled halfway around the
world and were recorded by an international network of instruments that
listens for nuclear explosions.
The explosion was heard by witnesses in Indonesia.
Video images of the sky following the event show a dust trail characteristic of an exploding asteroid.
Sudden impact
The amount of energy released suggests the object was about 10 metres
across, the researchers say. Such objects are thought to hit Earth
about once per decade.
No telescope spotted the asteroid ahead of its impact .
That is not surprising, given that only a tiny fraction of asteroids
smaller than 100 metres across have been catalogued, says Tim Spahr,
director of the Minor Planet Center in Cambridge, Massachusetts. Yet
objects as small as 20 or 30 metres across may be capable of doing
damage on the ground, he says.
"If you want to find the smallest objects you have to build
more, larger telescopes," says Spahr. "A survey that finds all of the
20-metre objects will cost probably multiple billions of dollars."
The White House must develop a policy to address the asteroid
hazard by October 2010 under a deadline imposed by Congress. It is
likely to be influenced by a report from the National Research Council
on the asteroid problem, which is expected by year's end.
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