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Fire in the Sky


Kenya's Rain of Meteorites

© Michael Farmer
Meteorite hunter Michael Farmer poses with Rose Kamande, who found this 7.7-pound (3.5-kg) stone on July 17, 2011 — one day after meteorites fell from the sky in the villages surrounding Thika, Kenya.
Statistically, every year roughly 1,400 meteorites of pebble size and larger fall somewhere on Earth's lands. But few of these are ever found - and even fewer (about 3%) are actually seen as they arrive. Because they're rare, these witnessed falls are especially prized both by scientists (because the stones are fresh and unweathered) and by meteorite collectors (they command higher prices).

As it happens, a bunch of meteorites fell from the sky over east-central Africa on July 16th, and only now are details of this extraterrestrial special delivery coming to light.

On that morning, residents in villages near Thika, Kenya, heard a loud explosion but didn't know what to make of the strange stones that fell around them. Local police were called to investigate a sizable one that dropped into a cornfield and carted it off for further study.

This is a desperately poor region, and it didn't take long for local villagers to realize that these plain-looking rocks might be worth something. Word of the event soon reached meteorite hunters, and within hours the chase was on.


Comet Elenin - the Final Prospect

As many readers already know, Comet Elenin has begun the irreversible process of breaking up. We spoke earlier about the probablility of such an outcome, but I considered it less than 50%. On the graph at left you can see a selection of ten comets that approach the Sun closer than 0.5 a.u. The red line shows the boundary, to the left of which, derived from J. Bortle's formula, is the safe zone, but to the right is the zone of disintegration. The yellow color shows Comet Elenin, with absolute magnitude obtained by visual observations, and the blue is from JPL-NASA data. As we see, Bortle's formula, all-in-all, doesn't work too badly. Although there is a bright exception - the green triangle belongs to the unique comet 96P/Machholtz, about which I will speak next time.

Now it is absolutely clear that the comet's drop in brightness, first noted by Michael Mattiazzo on Aug. 20th, was not coincidental - the decay process had already begun, and over the course of the next several days the comet changed greatly. Its pseudo-nucleus became diffuse and extended, and later vanished completely. On images from Sept. 1st in the comet's coma there was no condensation visible, and that meant the comet had already broken up into fairly small pieces, with a maximum size of not more than a hundred meters.


Space Junk Rising Exponentially (and No, It's Not Man-Made)

© Getty Images
Forget man-made space junk, the real threat is coming from further out in our solar system.
Scientists warn of 'tipping point' but shuttle's demise means there is no easy way to remove defunct satellites

The amount of junk in space is rising exponentially, with continuous collisions between abandoned equipment, spent rockets and other debris creating ever growing clouds of dangerous fragments, an influential report warned on Thursday.

The report, commissioned by NASA, says the quantity of hazardous material circling the Earth has reached a "tipping point" and poses a real and increasing danger to satellites and the International Space Station.

It suggests developing a clean-up strategy, which could include catching debris with nets, magnets or giant umbrellas.


US: That unidentified flaming object in Northland skies? It was a fireball, experts say

That object seen in the skies over the Northland last Saturday afternoon was a meteor bright enough to be seen during the day, according to the website of the American Meteor Society. The term for that is a daylight fireball.

It was a fireball.

That object seen in the skies over the Northland last Saturday afternoon was a meteor bright enough to be seen during the day, according to the website of the American Meteor Society. The term for that is a daylight fireball.

After Saturday's Eh? column reported someone seeing a "large object with flames coming from the back of it" over Lake County about 5:20 p.m. Aug. 27, several readers called and e-mailed with their observations.

Rita O'Connell said she and her mother, Millicent O'Connell, saw it about 5:23 p.m. when they were at the Moose Lake exit on Interstate 35. "In the sky high in front of us, about due north, we saw a flaming object falling at about an 80 degree angle from high left to lower right," she wrote.


Search for meteorite in west of Ireland

© Unknown
A meteor is seen in the sky above Spain last year
An appeal has been launched for help in locating a meteorite after a fireball was seen blazing across Irish skies last week.

An appeal has been launched for help in locating a meteorite that fell on Ireland.

Astronomy Ireland says it has received reports from around the country of a fireball seen blazing across the sky last week. The fireball was caused as fragments of a comet entered the Earth's atmosphere over Ireland on the night of Monday 22 August.

While most meteors are around the size of a grain of sand - fireballs such as the one seen last week are caused by larger objects hitting the Earth's atmosphere at speeds of around 100,000mph.

It is thought pieces of the meteorite may have survived the fall to the ground and landed in the west.


India: Delhi boys discover asteroid

Vaibhav Sapra and Sharanjeet Singh of Bal Bharati Public School, Pitampura, have discovered a Main Belt Asteroid, ensuring for themselves a name in history.

Conducted by non-government organisation Science Popularisation Association of Communicators and Educators (SPACE) in collaboration with the United States-based International Astronomical Search Collaboration, the All-India Asteroid Search Campaign-2011 concluded in August. It involved school and college students from across the country working with a special software to discover asteroids. The students, divided into groups of two each, collaborated and analysed their data for asteroid hunting. It was a difficult and challenging task for Vaibhav and Sharanjeet, both Science students, to jointly detect the asteroid from a series of pictures of the sky.


Wales, UK: Cardiff student discovers two new asteroids

© WalesOnline
Hannah Blyth: Helped discover asteroids on work experience
A stargazing schoolgirl made quite an impact on work experience when she discovered 22 new asteroids and a disintegrating comet.

Hannah Blyth, 18, had been chosen to do a summer work placement on the University of Glamorgan's Faulkes Telescope project when she made the remarkable finds.

The St John's College pupil single-handedly discovered two new asteroids, and together with astronomer Nick Howes and two of the world's leading comet and asteroid imagers, Giovanni Sostero and Ernesto Guido, discovered 20 others - not to mention the comet.

"I was not really expecting to be involved with the asteroids, never mind expecting to find new ones - and it was quite a rush, to tell the truth," said Hannah, from Castleton, who is hoping for a career in science.

"It was an extremely exciting moment when we discovered the asteroids, and something to remember. I'm very proud of the fact that I was part of something like that, I had a lot of fun."


US: 'Too Bright' Meteor Streaks Over Atlanta Skies

A very bright meteor streaked across the skies of Atlanta Sunday night, NASA scientists revealed Monday.

NASA said that the meteor was "too bright for the all-sky camera in Cartersville to accurately determine the center of light."

The Meteoroid Environment Office reported the meteor's initial speed was around 23.6 km per second (52,800 mph).

The all-sky camera in Cartersville, Georgia, operated by NASA's Marshall Space Flight Center in Huntsville, Ala., captured a video and photos of the spectacular meteor.

© NASA/MSFC/Meteoroid Environment Office
View of meteor from all sky camera located at Cartersville, Georgia.


China: Huge Bubble Cloud over Beijing Skies Mystifies Observers

Photos were posted online of a mysteriously huge bubble cloud over the skies of Beijing and surrounding areas Thursday, which raised concerns and discussions among netizens.

"At first, it's relatively small and bright, the upper part is something like a semi-circle, a spherical ring of light, it's obviously becoming bigger and bigger then."

When the observation team set their instruments at the bubble, it gradually became bigger and thinner. The entire occurrence lasted for less than 15 minutes. Observers took pictures of the whole process and posted them online.


Comet Elenin Could Be Disintegrating

© Michael Mattiazzo
C/2010 X1 Elenin, on Aug 29, 2011.
Astronomers monitoring Comet Elenin have noticed the comet has decreased in brightness the past week, and the coma is now elongating and diffusing. Some astronomers predict the comet will disintegrate and not survive perihelion, its closest approach to the Sun.

On August 19, a massive solar flare and coronal mass ejection hit the comet, which may have been the beginning of the end for the much ballyhooed lump of ice and dirt.

Comet Elenin as seen by the STEREO HI1-B on Aug. 6, 2011, from about 7 million kilometers from the spacecraft.
We've been following it in the STEREO spacecraft images and a number of amateurs have been following it in their telescopes," said Australian amateur astronomer Ian Musgrave, author of the Astroblog website. "Shortly after the coronal mass ejection the comet flared up and you could see some beautiful details in the tail, with the tail was twisting about in the solar wind. But shortly after that Earth- bound amateurs reported a huge decrease in the intensity of the comet. We think it may presage a falling apart of the comet."

One journalist joked that maybe Comet Elenin just couldn't take all the doomsday talk and publicity.

"It really has been a beautiful little comet and it deserves a better fate than to be overhyped by doom-sayers," said Musgrave.