The Gisborne Herald
Wed, 05 Nov 2008 20:26 UTC
Makaraka residents awoke with a start yesterday as a loud explosion rattled windows in the area.
Tony Walker said his first thought when he heard and felt the shock
wave at about 6.10am was that something had hit his family's house.
"All our neighbours in Granny Tarr and Tory Street also
thought something had hit their house. When I heard it I looked out the
window and saw someone had a fire going and thought it may have been an
aerosol can or something, but it sounded more like a sonic boom.
"It's not the first one, either - there was one around Christmas and it broke a mirror in the house."
Another Makaraka resident, Roger Handford, thought it sounded more earthbound.
"It wasn't coming from above, and it was too powerful to be fireworks.
It sounded like it was contained and there was a definite jolt."
A loud bang that was heard over a wide area last summer turned
out to be young men playing with acetylene near Back Ormond Road,
although Mr Walker did not think the explosion he heard was acetylene.
"I know what acetylene bombs sound like - I thought this explosion sounded more like a sonic boom."
The universe is full of water, mostly in the form of very cold ice
films deposited on interstellar dust particles, but until recently
little was known about the detailed small scale structure. Now the
latest quick freezing techniques coupled with sophisticated scanning
electron microscopy techniques, are allowing physicists to create ice
films in cold conditions similar to outer space and observe the
detailed molecular organisation, yielding clues to fundamental
questions including possibly the origin of life.
© iStockphoto/Christine Balderas
Physicists are creating ice films in cold conditions similar to outer space and observe the detailed molecular organization.
Physicists are creating ice films in cold conditions similar to outer space and observe the detailed molecular organization.
Researchers have been surprised by some of the results, not least
by the sheer beauty of some of the images created, according to Julyan
Cartwright, a specialist in ice structures at the Andalusian Institute
for Earth Sciences (IACT) of the Spanish Research Council (CSIC) and
the University of Granada in Spain.
Recent discoveries about the structure of ice films in
astrophysical conditions at the mesoscale, which is the size just above
the molecular level, were discussed at a recent workshop organised by
the European Science Foundation (ESF) and co-chaired by Cartwright
alongside C. Ignacio Sainz-Diaz, also from the IACT. As Cartwright
noted, many of the discoveries about ice structures at low temperatures
were made possible by earlier research into industrial applications
involving deposits of thin films upon an underlying substrate (ie the
surface, such as a rock, to which the film is attached), such as
manufacture of ceramics and semiconductors. In turn the study of ice
films could lead to insights of value in such industrial applications.
But the ESF workshop's main focus was on ice in space,
usually formed at temperatures far lower than even the coldest places
on earth, between 3 and 90 degrees above absolute zero (3-90K). Most of
the ice is on dust grains because there are so many of them, but some
ice is on larger bodies such as asteroids, comets, cold moons or
planets, and occasionally planets capable of supporting life such as
Earth.
At low temperatures, ice can form different structures at the
mesoscale than under terrestrial conditions, and in some cases can be
amorphous in form, that is like a glass with the molecules in effect
frozen in space, rather than as crystals. For ice to be amorphous,
water has to be cooled to its glass transition temperature of about 130
K without ice crystals having formed first. To do this in the
laboratory requires rapid cooling, which Cartwright and colleagues
achieved in their work with a helium "cold finger" incorporated in a
scanning electron microscope to take the images.
As Cartwright observed, ice can exist in a combination of
crystalline and amorphous forms, in other words as a mixture of order
and disorder, with many variants depending on the temperature at which
freezing actually occurred. In his latest work, Cartwright and
colleagues have shown that ice at the mesoscale comprises all sorts of
different characteristic shapes associated with the temperature and
pressure of freezing, also depending on the surface properties of the
substrate. For example when formed on a titanium substrate at the very
low temperature of 6K, ice has a characteristic cauliflower structure.
Most intriguingly, ice under certain conditions produces
biomimetic forms, meaning that they appear life like, with shapes like
palm leaves or worms, or even at a smaller scale like bacteria. This
led Cartwright to point out that researchers should not assume that
lifelike forms in objects obtained from space, like Mars rock, is
evidence that life actually existed there. "If one goes to another
planet and sees small wormlike or palm like structures, one should not
immediately call a press conference announcing alien life has been
found," said Cartwright.
On the other hand the existence of lifelike biomimetic
structures in ice suggests that nature may well have copied physics. It
is even possible that while ice is too cold to support most life as we
know it, it may have provided a suitable internal environment for
prebiotic life to have emerged.
"It is clear that biology does use physics," said Cartwright.
"Indeed, how could it not do? So we shouldn't be surprised to see that
sometimes biological structures clearly make use of simple physical
principles. Then, going back in time, it seems reasonable to posit that
when life first emerged, it would have been using as a container
something much simpler than today's cell membrane, probably some sort
of simple vesicle of the sort found in soap bubbles. This sort of
vesicle can be found in abiotic systems today, both in hot conditions,
in the chemistry associated with 'black smokers' on the sea floor,
which is currently favoured as a possible origin of life, but also in
the chemistry of sea ice."
This is an intriguing idea that will be explored further in
projects spawned by the ESF workshop. This may provide a new twist to
the idea that life arrived from space. It may be that the precursors of
life came from space, but that the actual carbon based biochemistry of
all organisms on Earth evolved on this planet.
The workshop, Euroice2008, was held in Granada, Spain in October 2008.
Adapted from materials provided by European Science Foundation.
The Register
Wed, 05 Nov 2008 04:21 UTC
Lester Haines
Aficionados of meteor showers should cast their eyes heavenwards on 5
and 12 November for what are expected to be "unusually good" displays
from the Taurids, possibly including fireball-inducing larger meteors
colliding terminally with Earth's atmosphere.
The Taurid meteors - so named because they appear to emanate
from the constellation Taurus - are the streamed remains of a
disintegrated comet which "probably coalesced into a cluster due to
gravitational tugs from Jupiter", as New Scientist puts it.
This cluster orbits the Sun every 3.4 years, so we don't always pass
through it. But this year we're making a "glancing pass" of the debris;
this began in October and will peak this month. The Taurids don't
entertain with as many meteors as the Leonids or Perseids, but this
time around they might offer around 20 burn-ups per hour.
The night of 5 November is reckoned to be the best bet, since
the 12th is an almost full Moon. Northern hemisphere skywatchers will
get the best view, although their southern hemisphere counterparts can
take advantage of three to five hours of activity "around midnight on
Wednesday, when the constellation Taurus is above the horizon".
The Taurids aren't the only remains of the
disintegrated comet - it also left comet 2P/Encke which NASA hoped to
examine with its CONTOUR spacecraft back in 2003. However, the probe
went awol in 2002, apparently as a result of an engine firing which
broke it in two.
© NASA/JPL/University of Arizona
A
trough carved by erosion in Mars' north polar region. The conical mound
indicates a buried crater underneath the ice-rich soil.
A
trough carved by erosion in Mars' north polar region. The conical mound
indicates a buried crater underneath the ice-rich soil.
New
images taken by NASA's Mars Reconnaissance Orbiter have revealed rare
evidence of an impact crater in Mars' north polar region.
Around the red planet's north pole is a feature called the north polar layered deposits, which are a series of ice-rich layers deposited over time and up to several kilometers thick.
The new images from MRO's
High Resolution Imaging Science Experiment (HiRISE) camera revealed an
odd, solitary hill rising part-way down an eroding slope of the layered
terrain.
The exposed section of the deposits is about 1,640 feet (500
meters) thick, and the conical mound is about 130 feet (40 meters)
high.
"The mound may be the remnant of a buried impact
crater, which is now being exhumed," said HiRISE team member Shane
Byrne, of the University of Arizona.
If it sounds backwards for a crater to be revealed by a mound, there's a fairly simple explanation:
The crater formed as the north polar ice layers were being
deposited. The crater itself would have been filled in by ice after it
formed.
Most of these craters are buried under the Martian surface and
inaccessible to scientists and their instruments. But this crater and
its associated ice mound were exhumed as erosion formed a trough above
and around it.
"For reasons that are poorly understood right now, the ice
beneath the site of the crater is more resistant to this erosion, so
that as the trough is formed, ice beneath the old impact site remained,
forming this isolated hill," Byrne said.
At high resolution, the HiRISE image shows that the mound is made up of polygonal blocks as big as 33 feet (10 meters) across.
The blocks are covered by the reddish dust that is ubiquitous
on Mars, but otherwise resemble ice-rich blocks seen in other images of
the north polar layered deposits.
Another new HiRISE image showed a small impact crater on the surface of Planum Boreum, or the north polar cap. This smaller crater is only about 125 yards (115 meters) in diameter.
The dearth of craters around Mars' north polar region has led
scientists to suggest that either the north polar cap is only about
100,000 years old, and therefore would have accumulated fewer impacts,
or that the craters disappear as the ice relaxes, just as imperfections
in an old window disappear as the glass relaxes.
Canada: Northern Alberta meteor crater identified
Alexandra Pope
Whitecourt Star
Wed, 05 Nov 2008 04:30 UTC
© Alexandra Pope
Chris
Herd, a professor in the University of Alberta's department of earth
and atmospheric sciences, photographs a crowd of local officials
gathered in the basin of a 1,000-year-old meteorite crater located on
Whitecourt's east mountain.
Chris
Herd, a professor in the University of Alberta's department of earth
and atmospheric sciences, photographs a crowd of local officials
gathered in the basin of a 1,000-year-old meteorite crater located on
Whitecourt's east mountain.
What local hunters in
Whitecourt thought for years was a sinkhole is actually the crater left
behind by a meteor that fell to earth 1,000 years ago and is now
attracting international attention from researchers.
George VanderBurg, MLA for Whitecourt-Ste. Anne, said he was
very surprised to learn about the crater. He recalled going hunting
with his father and using the site as a meeting point. Deer could often
be found drinking rainwater that collected in the bottom of the crater,
he said.
"All of us that have grown up here have known about it, but we didn't know it was the big scientific thing that it is," he said.
Chris Herd, a professor with the University of Alberta's department of
earth and atmospheric sciences who is leading the research on the
meteor crater, said he couldn't believe his ears when someone from the
area told him about the crater last year.
"We still joke about how skeptical I was on the phone, because
we literally get hundreds of these calls every year," Herd said in an
interview at the crater site last Monday. "This is very exciting."
The crater is 36 metres wide and six metres deep, which is
small as far as most craters go, Herd said. At an estimated 1,000 years
old, it is also one of the youngest craters in the world. The
second-youngest crater in Canada, located in Quebec, is 1.2 million
years old.
Herd said the meteor, which was made primarily of iron, was
probably formed very early in the life of the solar system by the same
process that formed the earth's core. Herd thinks the meteor came from
the asteroid belt and measured one metre across. However, researchers
have so far found 74 different pieces of the original meteor - which is
called a meteorite once it hits the ground - scattered around the
crater, some up to 70 metres away.
"The big mystery is the relationship between the meteorites and the event," Herd said.
Herd explained that most meteors travel so fast, they are completely
vaporized when they hit the earth. In some cases the pressure of
earth's atmosphere slows a meteor down enough to leave a portion of it
relatively intact when it lands.
But something happened to the Whitecourt meteor on its way to
earth, Herd said. The meteorites found around the crater have sharp
edges, which tell researchers a story about what might have happened to
the meteor before it hit the ground.
"The rock was ripped apart on impact or at a low altitude,"
Herd said. "Otherwise the atmospheric pressure would have rounded (the
edges of the meteorites)."
The site is one of only 12 of its kind in the world and has been very well preserved, Herd said.
"It's a phenomenal opportunity for the research that I do," he said.
Lindsay Blackett, Alberta minister of culture and community
spirit, said the big concern for local authorities is how to prevent
meteorite hunters from coming to the site and digging up meteorite
fragments.
The province will designate the site as a historic resource
and post signs asking visitors to do their part in preserving it, but
researchers fear that won't stop some meteorite collectors from
stealing rocks.
"You really just have to count on the local community to keep
an eye on it," Blackett said. "I think people having a vested interest
in this site will (encourage them) to keep an eye on it."
VanderBurg said once the researchers have finished their work,
the site could be a great educational opportunity for the public and
local students.
"This is the kind of place that inspires kids to go out and seek careers in science," he said.
Unidentified bright light seen streaking across Front Range
Denver - Just before 7 a.m. on Sunday morning, viewers from across the Front Range began contacting the 9NEWS Information Center saying they had seen what they thought was a meteor.
From Lakewood up to Fort Collins, viewers report seeing a large
red/orange ball with a green tail streaking across the sky, between
6:36 and 6:39 a.m.
Calls and e-mails sent to the University of Denver's
Department of Physics and Astronomy, the Denver Astronomical Society,
and the Fiske Planetarium on the campus of the University of
Colorado-Boulder were not immediately returned.
The Denver Museum of Nature and Science says the color is due to the
chemical composition of the meteor. It creates different colors as it
burns through the atmosphere.
The museum is not sure where the meteor landed. Museum
officials would like to hear from anyone on the western slope who saw
it. They also would like to see any video of the meteor. To report
meteor sightings or video to the museum, go to www.cloudbait.com and fill out the meteor report.
NASA Surprised by Unexpected Meteor Outburst
Space.com
Tue, 11 Nov 2008 06:25 UTC
When NASA meteor expert Bill Cooke arrived at the Marshall Space Flight
Center and checked his email Sept. 9, 2008, he was very surprised to
learn that he'd slept through a dramatic event.
A flurry of shooting stars had lit up the pre-dawn skies, including more than two dozen fireballs brighter than Venus. Cooke's all-sky Sentinel camera recorded the whole thing and had left him an email summarizing the outburst.
"Our Sentinel system consists of a computer-controlled camera,
fisheye lens and digital video recorder," Cooke explained. "It was
developed by researchers at the University of Western Ontario for
studies of meteors over Canada, and now we've adapted it for our
purposes. Every night, Sentinel patrols the sky, looking for the
unexpected, and it never gets sleepy."
© NASA/MSFC
The
unexpected September Perseid meteor shower was captured by the
automated Sentinel all-sky camera in this composite of images from
Sept. 9, 2008.
The
unexpected September Perseid meteor shower was captured by the
automated Sentinel all-sky camera in this composite of images from
Sept. 9, 2008.
An annual meteor shower around Sept. 9
was known to scientists, but it has always involved a few dim streaks
coming from the constellation Perseus. It is called the September
Perseids, and it had never measured up to the more dramatic August Perseid meteor shower. So few if any meteor enthusiasts ever bothered to watch the September event.
"Now we know better," Cooke said in a statement yesterday. "The September Perseids of 2008 were fantastic."
[The November Taurid meteor shower may generate a few bright fireballs through tomorrow.]
A meteor shower is typically generated by debris left behind by a comet
-- grains of ice and dirt ranging from the size of sand grains to peas.
The comet responsible for the September Perseids is unknown, but it
must have laid down multiple debris streams as it orbited the sun. This
year, Earth ran into a denser stream, Cooke figures.
There could be many unknown streams of debris crossing Earth's
orbit, in fact. "We can discover new meteoroid streams that could pose
a threat to spacecraft and satellites -- or just put on a pretty show
from time to time," Cooke said.
Cooke's team has since set up a second camera, 100 miles away,
to make the Sentinel system able to determine the direction from which
a meteor comes. This would allow scientists to figure out the orbit of
the comet involved.
The first successful test of the two-station Sentinel system came on
Oct. 1, when a centimeter-sized meteoroid hit Earth's atmosphere over
the southeastern United States with about as much energy as 500 pounds
of TNT. Both cameras recorded the fireball.
© NASA/MSFC
On
Oct. 1, 2008, a centimeter-sized meteoroid hit Earth's atmosphere over
the southeastern United States with about as much energy as 500 pounds
of TNT. It was captured by the automated Sentinel all-sky camera.
On
Oct. 1, 2008, a centimeter-sized meteoroid hit Earth's atmosphere over
the southeastern United States with about as much energy as 500 pounds
of TNT. It was captured by the automated Sentinel all-sky camera.
Using software developed by Rob Weryk of the University of Western
Ontario, the Sentinel system automatically calculated the orbit of the
meteoroid and emailed the results to Cooke. "It came from the asteroid
belt," he said.
Arkansas, US: Loud booms in Fort Smith area may be due to meteors
KFSM.com
Tue, 11 Nov 2008 17:22 UTC
Jared Broyles
Fort
Smith - A loud boom sounding similar to an explosion rocked the quiet
western Arkansas night. No police or fire responded to an accident
scene though. So what did Northwest Arkansas and River Valley residents
hear? 5NEWS investigated and found a logical explanation.
Not only did residents in our region hear the massive boom,
one from Spiro and several from Beaver Lake reported seeing yellow and
green flashes of light. A spokesman for NASA says he's not aware of
what it was but didn't disagree with the theory that a meteor might be
to blame.
Calls started pouring into the Fort Smith P.D. between 8:30 and 9 Sunday night.
"Have ya'll had any reports of anything blowing up or an explosion or
anything?" One man said when he called into Fort Smith Police. "We
heard an explosion and the house shook," another woman reported.
Eureka Springs Police took several calls from residents near
beaver lake who reported seeing yellow and green streaks like these.
Meanwhile, dispatchers and police were puzzled about what it could be.
"We can't find anything we checked all over," a Fort Smith dispatcher told authorities at Fort Chaffee.
On spaceweather.com a Spiro, Oklahoma man reported seeing quote
'several taurid fireballs'. With human explosions ruled out as a
possibility, UA expert Professor Derek Sears says a solar source may be
to blame.
"It is feasible for large meteors to make sonic booms," Sears told 5NEWS.
Basically, a meteor is bright trail that appears in the sky when space debris burns and gives off light.
"Sometimes if it was a really big object it would stay around for 10,
20 seconds," Sears said. "If it was a fairly small object and it's
burning up high in the atmosphere it could just be a flash."
But while meteor expert Derek Sears admits the fireballs may
have been taurids, he says leonids are more likely. Sears says they are
bigger, stronger meteors that come from the constellation Leo, not
Taurus.
Interestingly enough, Sears says the event was so big that it
may have had nothing to do with either the taurid or leonid showers.
He says it could simply have been a random event. According to Sears it
would take at least three separate videos of the fireball to know for
sure.
UK: Fireball spotted over Worcester
Sally Jones
Worcester News
Wed, 12 Nov 2008 00:39 UTC
A "fireball" was spotted over Worcester this evening. Joseph Smith, of
Beaconhill Drive, St John's, had stepped outside for a cigarette at
about 5.30pm when he saw a large ball of orange.
"It was the size of the moon," he said. "I've never seen anything like it. It looked like a fireball."
Mr Smith said the unidentified object looked to be over the racecourse direction.
Did you see the object? If so contact the newsdesk on 01905 742244.
Meteor showers appearing back-to-back next week
The China Post
Wed, 12 Nov 2008 09:16 UTC
People in many areas of Taiwan will have the opportunity of witnessing
two waves of rare and spectacular meteor showers are set to appear next
week.
Astronomers at the Taipei Astronomical Museum said people will
be able to see the upcoming meteor showers with naked eyes under fair
weather conditions.
Most shooting stars of the Leonid meteor shower are most likely to appear on next Monday, Nov. 17.
Star gazers may see an average of 20 meteors appear every hour.
The shooting stars of the Alpha-Monocerotids (commonly known as "kirin"
in Chinese) will have the highest concentration at around 5:25 p.m. on
next Friday, Nov. 21.
Astronomers said the two waves of meteor showers take place regularly during the month of November each year.
The most ideal time for appreciating the meteor showers starts from 11:30 p.m. until dawn the next day.
The lucky ones may see both meteor showers at the same time
because they sometimes appear in the sky simultaneously, said the
astronomers.
Indiana, US: Official says boom, shake not an earthquake
Green County Daily World
Wed, 12 Nov 2008 09:26 UTC
Nick Schneider
A spokesman with the U.S. Geological Society says a "boom and shake"
felt in the Bloomfield area on Tuesday evening was not related to
earthquake activity.
The Greene County Daily World received a call from a female
caller about 6 p.m. Tuesday, who inquired if there were any reports of
an earthquake in the area north Bloomfield. She said there was a boom and some shaking felt.
An initial check with the U.S. Geological Society -- the agency that
tracks earthquake activity -- showed there was no earthquake activity
in any region of the state of Indiana on Tuesday.
A follow-up call on Wednesday morning, confirmed the earlier
determination that the shaking was probably caused by something other
than seismic activity.
Randy Baldwin, a geophysicist with U.S. Geological Society's
Earthquake Center in Colorado, said, "I've been sitting here all night
and there was nothing in that region. I don't see anything. It could
have been a sonic boom."
A real-time map showing current seismic activity can be accessed by clicking on the following link.
Seattle, Washington - What was that bright light?
Several people called KOMO Thursday evening to report they had just
witnessed a brilliant light streak across the southern skies.
"It's amazing, it was probably a 3-second little light show," said one caller.
"And I saw what I thought was a shooting star and it shot
across the sky and it was white -- and you could see a tail," said
another.
Stephen Moran with the American Astronomical Society says based on reports, the second caller was on the right track.
"Normally when you say 'shooting star', it's not all that bright --
something you can see on any dark night if you wait long enough," Moran
told KOMO 1000 News. "But one that got the attention of people while
they're driving -- that's rarer and much brighter and called a
'fireball.' You will normally see them for a few seconds. Some very big
ones you can see for maybe 10 seconds. It's just a very small piece of
space debris, maybe just the tip of a comet or asteroid that comes too
close to the Earth and falls to the atmosphere and burns up."
The streak could be related to the Taurid Meteor Shower, which
spans several weeks in the autumn and Thursday was just a few days
after the peak. Astronomers report this year's shower has had several
fireball sightings.
Moran says while these meteor bits burn up long before it hits the ground, scientists have found that tiny, microscopic pieces of these meteor strikes will survive and trickle down to Earth.
"Statistically, there's probably one or two pieces in your hair
right now," Moran said of "space dust" due to past meteor burn-ups over
the ages.
Here are some images captured a few days ago in the Midwest, for those that saw Thursday night's streak to compare.
If you captured images or video of the event, or perhaps have a
surveillance or web camera that might have captured the event, e-mail
us or post it in our YouNews site and we might show it on air.
Comment: More
and more scientists are now quietly slipping in the fact that
meteorites actually leave behind dust that stays in the upper
atmosphere and eventually falls to earth.
There is much, much more about this phenomenon in the article New Light on the Black Death: The Cosmic Connection.
Suspected Ohio plane crash may have been meteor
Associated Press
Fri, 14 Nov 2008 14:13 UTC
Authorities who spent four hours searching for a plane crash in
northeast Ohio now think what people saw and heard may have been a
meteor.
Reports Thursday afternoon of a bright light and trail
of smoke in the sky and a separate call about a crashing sound in Lake
County northeast of Cleveland sparked a search that involved three
helicopters, several police and fire departments and the State Highway
Patrol.
Madison Township police Sgt. Rick Barson says based on what
the witnesses reported, investigators believed an ultralight plane had
gone down. But Barson says no wreckage was found.
He says a meteor would be "highly unusual," though he says even a small one has an explosion on impact.
By nightfall, no evidence of a meteor had turned up either.
Shooting stars to decorate evening sky
Steve Marroni
Evening Sun
Sun, 16 Nov 2008 03:19 UTC
A little friendly advice for this weekend. Brace yourselves.
The Earth is heading at 66,000 miles per hour into a field of cosmic
debris. Meteors will plummet to the planet, some as fast as 150,000
miles per hour.
Don't worry, though. This happens every year. And, most of
that space junk just burns up in the atmosphere. But, it will make for
one pretty cool light show.
Bill Kreiger, assistant professor of Earth science at
York College, said that Sunday through Tuesday will be the best days to
see a meteor shower - a persistent firing of shooting stars streaming
across the evening sky.
You can see them through the end of the month, but starting this weekend will be the best show.
You're often lucky to catch a glimpse of a shooting star on a
normal night, but on these nights, all you have to do is look up into a
dark, clear sky. Meteors can be seen as frequently as one per minute,
he said.
The debris of the Leonid meteorites was left behind by the
Tempel-Tuttle Comet, which passes through our neck of the solar system
every 33 years. Kreiger explained as the icy comet shoots through, it
leaves behind a cloud of dust and rocks. The biggest storms can be seen
in the years after the comet passes through.
Kreiger said a comet is a lot like a snowball rolling down the
road. It picks up rocks and dirt. As it flies through space, the icy
ball of the comet dissipates, leaving behind potential meteor showers
if a planet happens to orbit through the area.
Tempel-Tuttle's last pass was in 1998, so there's still plenty of space junk to put on a light show.
Junk might not actually be the right word for what meteorites are.
"Meteorites are so valuable," Kreiger said.
They're packed with information about the atmosphere and the universe,
he said. "Their chemical composition indicates quite a bit," he said.
Most meteorites burn up in the atmosphere, but some do not
completely vaporize and actually land. A large chunk is usually the
size of a walnut, sometimes bigger.
Six meteorites have been recorded to have landed in
Pennsylvania, Kreiger said. The 1907 Shrewsbury Meteorite is on display
at the Pennsylvania Academy of Science Museum.
They look pretty, he said, but they can be a danger to satellites.
According to stardate.org,
the best time to see the meteor shower is in the early morning hours.
They can best be seen on a dark night. The moon rises in the late
evening. Bright moonlight often makes meteor-gazing difficult.
If you live near a lot of bright lights, drive out into the
country for a better view. Let your eyes adjust to the dark, and as
soon as you can see all the stars of the Little Dipper, your eyes are
ready for the show.
The showers will seem to fall from the area of the constellation of Leo.
Early warning of dangerous asteroids and comets
David Chandler
MIT News
Mon, 17 Nov 2008 16:46 UTC
© MIT Lincoln Laboratory
Pan-STARRS 1 prototype, part of the Panoramic Survey Telescope and Rapid Response System, Haleakala mountain, Maui
Pan-STARRS 1 prototype, part of the Panoramic Survey Telescope and Rapid Response System, Haleakala mountain, Maui
Detectors developed at Lincoln Laboratory deployed in powerful telescope
Silicon chips developed at MIT Lincoln Laboratory are at the heart of a
new survey telescope that will soon provide a more than fivefold
improvement in scientists' ability to detect asteroids and comets that
could someday pose a threat to the planet.
The prototype telescope installed on Haleakala mountain, Maui,
will begin operation this December. It will feature the world's largest
and most advanced digital camera, using the Lincoln Laboratory silicon
chips. This telescope is the first of four that will be housed together
in one dome. The system, called Pan-STARRS (for Panoramic Survey
Telescope and Rapid Response System), is being developed at the
University of Hawaii's Institute for Astronomy.
"This is a truly giant instrument," said University of
Hawaii astronomer John Tonry, who led the team developing the new
1.4-gigapixel camera. "We get an image that is 38,000 by 38,000 pixels
in size, or about 200 times larger than you get in a high-end consumer
digital camera."
Pan-STARRS, whose cameras cover an area of sky six times the
width of the full moon and can detect stars 10 million times fainter
than those visible to the naked eye, is also unique in its ability to
find moving or variable objects.
Lincoln Laboratory's charge-coupled device (CCD) technology is
a key enabling technology for the telescope's camera. In the mid-1990s,
Lincoln Laboratory researchers Barry Burke and Dick Savoye of the
Advanced Imaging Technology Group, in collaboration with Tonry, who was
then working at MIT, developed the orthogonal-transfer charge-coupled
device (OTCCD), a CCD that can shift its pixels to cancel the effects
of random image motion. Many consumer digital cameras use a moving lens
or chip mount to provide camera-motion compensation and thus reduce
blur, but the OTCCD does this electronically at the pixel level and at
much higher speeds.
The challenge presented by the Pan-STARRS camera is its exceptionally
wide field of view. For wide fields of view, jitter in the stars begins
to vary across the image, and an OTCCD with its single shift pattern
for all the pixels begins to lose its effectiveness. The solution for
Pan-STARRS, proposed by Tonry and developed in collaboration with
Lincoln Laboratory, was to make an array of 60 small, separate OTCCDs
on a single silicon chip. This architecture enabled independent shifts
optimized for tracking the varied image motion across a wide scene.
"Not only was Lincoln the only place where the OTCCD had been
demonstrated, but the added features that Pan-STARRS needed made the
design much more complicated," said Burke, who has been working on the
Pan-STARRS project. "It is fair to say that Lincoln was, and is,
uniquely equipped in chip design, wafer processing, packaging, and
testing to deliver such technology."
The primary mission of Pan-STARRS is to detect
Earth-approaching asteroids and comets that could be dangerous to the
planet. When the system becomes fully operational, the entire sky
visible from Hawaii (about three-quarters of the total sky)
will be photographed at least once a week, and all images will be
entered into powerful computers at the Maui High Performance Computer
Center. Scientists at the center will analyze the images for changes
that could reveal a previously unknown asteroid. They will also combine
data from several images to calculate the orbits of asteroids, looking
for indications that an asteroid may be on a collision course with
Earth.
Pan-STARRS will also be used to catalog 99 percent of stars in
the northern hemisphere that have ever been observed by visible light,
including stars from nearby galaxies. In addition, the Pan-STARRS
survey of the whole sky will present astronomers with the opportunity
to discover, and monitor, planets around other stars, as well as rare
explosive objects in other galaxies.
Detailed information about the Pan-STARRS design and its science applications can be found here. The project was funded by the U.S. Air Force Research Laboratory.
Wales: No explanation after 'earthquake'
Tue, 18 Nov 2008 16:16 UTC
BBC News
People
living on Anglesey have been left baffled about the cause of a loud
noise which shook their homes and made pots and pans rattle.
Anona Jones said she was in the kitchen of her home at Llanddaniel near
Gaerwen when she heard a loud "rumbling" noise at 1425 GMT.
A spokesman at the British Geological Survey in Edinburgh said no seismic activity had been measured in the area.
But he added that a number of calls had been received about the noise.
"It was a very obvious noise, and I thought there had been an earthquake," said Mrs Jones.
"I was in the house with my husband and a local farmer, and
we'd just sat down to have a cup of tea at about 2.25 this afternoon."
"We all heard this rumbling getting nearer and nearer the house.
"The cooker hood began to shake and the saucepans on top of the microwave rattled," she added.
Mrs Jones said she had rung her sister-in-law in Llanfairpwll and she too had heard the noise.
A spokesman at the British Geological Survey in Edinburgh said no instruments in Wales had measured a seismic event on Tuesday.
'Sonic boom'
"We have had quite a few people from the Gaerwen area of
Anglesey ringing us asking about it, but there are no reports of
tremors, no detection that it was a seismic event," he said.
The most probable explanation was that it was some kind of sonic boom, which could be created by aircraft, he added.
"I don't know if that is what it was, but sonic booms have all the characteristics of this kind of event," he said.
In May 2006 people living on the island, as well as on the
mainland of north Wales, were woken in the middle of the night by a
tremor.
The shock wave measured 1.4 on the Richter scale at 0322 BST.
Comment: Another
probable explanation is that the sonic boom and the quake were produced
by a small meteorite impact within the area. These sightings and
reports are becoming more frequent in recent years.
Massive fireball lights up Canadian Prairie skies
Laura Drake
Edmonton Journal
Fri, 21 Nov 2008 16:00 UTC
It wasn't a bird, and it sure as heck wasn't a plane, but whatever was
in the sky over western Canada on Thursday night was very exciting for
the people who saw it.
In Edmonton and across the Prairies, hundreds of people
reported seeing a bright flaming object light up the sky around 5:30
p.m. local time. It was variously described as green, yellow, purple or
blue, and appeared as either an explosion or an object streaking
through the sky.
Sightings came from across the Prairies; from as far south as
Medicine Hat, Alta., to as far north as Beauval, Sask. - 600 kilometres
from Edmonton.
A mysterious bright light lit up the evening sky over Edmonton just
before 5:30 p.m. There are reports that the phenomenon was seen as far
north as Fort McMurray and as far east as Saskatchewan.
Marcel Gobeil, who lives on a farm south of Edmonton, was in
his living room when he heard what he describes as a "loud boom,"
followed by bright colourful light in the sky.
"At first I thought it was fireworks," said Gobeil. "I've
never seen anything like it; it was green and blue and then turned to
bright red. It was pretty big."
Gobeil said he thought the object hit the ground about 10 seconds later.
"It seemed like it fell on Beaumont, but it's more likely it landed in Manitoba or Saskatchewan if it was a meteorite," he said.
Hundreds of kilometres to the east, farmer Bruce Trapp also saw the light show.
"It lit up the yard almost like midday, but just for an instant," said
Trapp, who farms about 70 kilometres southwest of Saskatoon. "It was
far brighter than any lightning strike I've ever seen."
Shawn Mitchler was pumping gas at Radisson, Sask., about 60
kilometres northwest of Saskatoon, when the sky flashed green and
yellow.
"It seemed like fireworks or a missile coming down," said Mitchler, who estimates the light show lasted five to 10 seconds.
"My heart just started racing because I didn't know what it was."
Edmonton International Airport spokesman Jim Rudolph said "the skies east of the airport lit up" at 5:27 p.m.
"According to NavCanada, it appears that this was the result of
a meteorite, but that has not been confirmed," said Rudolph, adding
that operations at the airport were not affected.
"What we probably saw was a fireball, which is the result of a
rock coming into the atmosphere," said Chris Herd, an associate
professor in the University of Alberta's department of earth and
atmospheric sciences and curator of the university's meteorite
collection.
"The big question now is whether or not anything hit the ground."
Richard Huziak, a member of the Royal Astronomical Society who
lives in Saskatoon, believes it was likely a meteor that did land
somewhere near the Alberta-Saskatchewan border.
It may be possible to determine a more precise location, since
fireball video cameras designed to begin recording when a bright light
appears in the sky are located in Saskatoon, Regina, Moose Jaw,
Edmonton and Calgary.
"It's very likely this one has been caught. It will show the
track through the sky and might show the orbit back into space," Huziak
said.
But while many of the witnesses claimed to see something land,
Herd said this was most likely an optical illusion. Since the fireball
was a bright light several kilometres up in a dark sky, it would have
appeared close to anyone who could see it. If something did fall to the
Earth, it's extremely unlikely anyone would have witnessed it, Herd
said. As the object fell through the Earth's atmosphere, it would slow
down and the resulting decrease in friction would cause it to stop
burning.
"What we know about fireballs is that they're bright burning
up for a certain amount of time in the atmosphere, but then they stop
burning brightly. If there's a rock that continues after that, it's
falling in dark flight," he said.
"This could literally be a couple of kilometres up in the air
and it could fall the whole rest of the way without giving off any
light. It could drop like a rock to the ground."
Herd said while fireballs are quite frequent, they don't generally happen over populated areas.
"Something as bright as this is pretty rare," he said.
If something did ultimately hit the ground, Herd said, it would be a very exciting find.
"It's not often that something actually lands and is found, because of
all the factors that are working against you," he said, adding he hopes
anyone who finds a new rock in their yard tomorrow will get in touch
with him.
Meteorites often fall to Earth, but very few cause damage
because the rocks often disintegrate as they travel through the
atmosphere.
For those who witnessed the fireball, Herd suggested they
report it to the Meteorites and Impacts Advisory Committee to the
Canadian Space Agency, which can be found at Miac.uqac.ca.
With files from Jamie Hall, Lana Haight, Saskatoon StarPhoenix
Edmonton, Canada: Mysterious fireball lights up night sky
CTV Edmonton
Fri, 21 Nov 2008 22:37 UTC
Numerous people living in Edmonton and surrounding areas are reporting seeing a meteorite-like fireball that lit up the sky.
It not been confirmed as a meteor by official sources, but many
witnesses report seeing "bright orange flames" with a large tail that
shot horizontally across the sky and then disappeared.
Others said it looked like horizontal lightning, where all the clouds in one huge swath were lit up.
Richard Bellington said he was driving north of Highway 2 on his way to Edmonton when he saw the sky light up.
The flames were so bright and appeared to travel so close to the ground that he called 911.
South Edmonton resident Peter Koroluk said it was hard to tell where it landed.
"It came down with a huge tail following and it had lit up past
way behind it attached to the ball," he said. "This ball was about the
size of a football."
Callers as far as Onoway, Beaumont and Cold Lake also report seeing the
ball of flames. Stations as far north as Fort McMurray are also passing
along sightings.
Some experts say the fireball could be part of the Leonids
meteor showers, where activity has been predicted to begin on Nov. 17.
Officals with NORAD, or the North American Aerospace Defence
Command, confirm it was not a man-made object and it poses no threat to
North American security.
Chris Herd, a meteorite scientist at the University of Alberta, said people shouldn't panic after seeing such a sight.
"The sky's a big place," he said. "It can play tricks, these
fireballs can play tricks with you and it can look like they fell over
there, when it actually can be tens of thousands of kilometres away.
The fact that we've got reports as far away as Cold Lake, Saskatoon and
Airdrie tells you can see it from a long ways away."
Comment: Yes, perhaps it is so. But it doesn't
mean that people shouldn't panic, especially if there is a heavily
populated city or perhaps an industrial area located 'tens of thousands
of kilometres away'.
This is no word whether the meteorite actually hit land.
Meteor lights up the Thanksgiving sky
Komo News
Thu, 27 Nov 2008 06:54 UTC
Seattle -- They say timing is everything. Boy, were we lucky.
Our Queen Anne Tower camera just happened to be rolling on air during
KOMO 4 News at 5 a.m. and captured a meteor fireball streaking across
the Seattle sky.
Just as anchor Mike Dardis was welcoming viewers back form a
commercial break at 5:15, there went the shooting star right on cue.
It's at least the second time this month a meteor has streaked across the sky. We also received several reports of a fireball on the evening of November 13th.
The streak could be related to the Taurid Meteor Shower, which spans
several weeks in the autumn. Astronomers report this year's shower has
had several fireball sightings.
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