06 November 2008

November 2008

New Zealand: Early morning explosion 'like a sonic boom'
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."



Could Life Have Started In Lump Of Ice?
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.
ice films
© iStockphoto/Christine Balderas
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.



Taurid meteors promise Guy Fawkes fireball show
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.




Huge Meteor Crater Found Underneath Martian Ice
Martian crater
© 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.
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
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.



US: Colorado Front Range meteor?
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
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."

Perseid Metoers
© 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.
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.
Perseid Meteor
© 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.

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
meteor
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
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
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
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.



US: Bright light streaks across Puget Sound skies
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
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
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
Pan-STARRS 1 prototype
© MIT Lincoln Laboratory
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'
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
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
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
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.



Meteor streaks across the Seattle skies, captured on KOMO 4
News' Queen Anne Tower cam during the 5 a.m. newscast,
November 27, 2008.



It seems we got off lightly in the cosmic lottery. Deadly comet impacts may be much rarer in our solar system than in others nearby.

We can't directly measure the rate of comet collisions in other solar systems but we can detect signs of the dust that such smashes kick up because the dust gets warmed by the star and so gives off infrared radiation. That radiation shows up as extra infrared in the spectrum of light coming from the star. Because such dust should dissipate quickly, it is thought to provide a good snapshot of the recent collision rate.

Jane Greaves of the University of St Andrews, UK, analysed observations by the Spitzer Space Telescope and found that the vast majority of sun-like stars near us have more dust than our solar system does and therefore have had more collisions in their vicinity. Our solar system may be one of the few that have been safe for life. Greaves presented her results at the Cosmic Cataclysms and Life symposium in Frascati, Italy, this month.
comet being torn to shreds around a dead star
© C GSF/Caltech/JPL/NASA
This artist's concept illustrates a comet being torn to shreds around a dead star, or white dwarf, called G29-38.


About 25 per cent of the stars have a very strong dust signature. The rest of them have too little dust for it to be readily apparent when each spectrum is studied in isolation. Adding the measurements from these stars together, however, is like looking through a stack of slightly dusty windowpanes, making the total amount of dust easier to see. Greaves's analysis revealed that 90 per cent of solar systems are dustier and so more collision-ridden than our own.

Mark Wyatt of the University of Cambridge agrees that the rate of comet impacts is probably lower in our neck of the woods. But as the temperature of the dust found by Greaves indicates it tends to sit far from the parent stars, the impacts might not have affected life on habitable planets, which would sit closer to their star, he says.

Comment: While comet impacts may be "much rarer" in our solar system than others, it certainly does not mean they do not strike ours. For a more enlightening and detailed study, read Forget about Global Warming, We are One Step From Extinction!



'Bright as a Sun': Scientists find space rock that streaked through skies of Western Canada
canada meteorite
© The Canadian Press/Geoff Howe
University of Calgary graduate student Ellen Milley poses with fragments of a 10-tonne meteorite she found in a small pond approximately 40 kilometres from Lloydminster, Sask., Friday, Nov. 28, 2008, several days after the space rock created a massive fireball crossing the sky Nov. 20.
The light was fading late Thursday afternoon when the two scientists drove through this pretty little valley just east of the central Saskatchewan-Alberta boundary, but it was still bright enough to spot something on a modest little pond.

"It was a piece of rock frozen into the pond," said University of Calgary graduate student Ellen Milley. "It triggered us to stop."

Geologist Alan Hildebrand knew as soon as he got a close look at it and the other bits of black, dimpled rock nearby that he was looking at emissaries from outer space.

"I know what a meteorite looks like and these are meteorites, very simple," he said.

The fist-sized chunks of black, dimpled rock are small fragments of a 10-tonne meteor that blazed across Prairie skies last week, older than the Earth and from an as-yet-undetermined asteroid belt unimaginably far away.

"It is very cool," said Milley.

People in Manitoba, Saskatchewan and Alberta have been buzzing about the huge fireball that lit up the night sky over the three provinces on Nov. 20. Witnesses reported hearing sonic boom rumblings and said the fiery flash was as bright as the sun.

In all, Milley and Hildebrand collected about 12 pieces of that giant space rock in and around the pond.

The largest weighed 250 grams and smallest a mere 10 grams. Larger pieces are expected as teams search along the path the asteroid took to the Earth's surface.

As meteorites go, there doesn't seem to be anything unusual about this one, said Hildebrand. Still, any rock from space is special.

"These rocks are 4.5 billion years old," he said. "They date from the origin of the solar system.

"They tell us about a time we have no other sample of."

As well, because so many saw the meteor's descent, scientists will be able to plot where it came from.

"That's only been done nine times before," Hildebrand said.

Ian Mitchell, who owns the land where the fragments fell, said for years the family has called the small body of water that they stock with trout every summer "the fish pond."

"I guess we'll call it the meteorite pond now," Mitchell joked, adding that his 12-year-old son was thrilled to learn that bits of outer space had landed in his family's fields.

Mitchell thought there was a chance something might turn up on one of his fields.

"I was thinking it would be neat if we found something, but I never expected this. As it turns out, I've been driving by these (rocks) for several days now."

The pieces are owned by the owner of the land on which they are found. Under Canadian law, meteorites may be bought and sold, but a federal permit is required to export them.

Meteorites can be valuable, but Mitchell doesn't seem starry-eyed about that.

"For now, it's souvenirs," he said. "We'll see. Sell, donate ... I'm not really sure yet."

His biggest concern is that his land isn't overrun with rockhounds. He said he plans to restrict access as much as possible until a proper search can be organized.

The university estimated there could be thousands of meteorite pieces strewn over a 20-square-kilometre area.

Hildebrand, a co-ordinator of the Canadian Fireball Reporting Centre with the Canadian Space Agency, estimated that the meteor could have been seen as far as 700 kilometres away, into the northern United States.

It contained about one-tenth of a kiloton of energy when it entered the earth's atmosphere on Nov. 20, roughly the equivalent of 100 tons of the chemical explosive TNT.

"It would be something like a billion-watt light bulb," he said.

Besides sonic boom sounds, witnesses also reported hearing hissing or crackling noises like frying bacon.

Fireballs can act as radio transmitters, Hildebrand said, causing odd sounds.

The largest meteor shower in Canada occurred northeast of Edmonton near the town of Bruderheim in 1960. More than 700 fragments were recovered, and together they weighed a total of 300 kilograms.

This latest meteor has captured the imagination of sky watchers around the world.

Robert Haag, a space rock collector from Arizona, has offered up to $12,000 for the first one-kilogram chunk of the meteor that is found.

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