Fire in the SkyS


Meteor

A history doomed to be repeated? Micro-meteorites rocked Earth's early climate

meteorite
© iStockphoto / duuuna
A new research has claimed that bombardments of 'micro-meteorites' on Earth and Mars four billion years ago may have caused the planets' climates to cool dramatically, hampering their ability to support life. Scientists from Imperial College London studied the effects of the Late Heavy Bombardment (LHB), a period of time in the early Solar System when meteorite showers lasting around 100 million years barraged Earth and Mars.

This bombardment discharged sulphur dioxide into the upper atmospheres of both planets and the researchers'' analysis suggests that this may have had a catastrophic impact on their environments.

Micro-meteorites come from the rocky asteroid belt between Mars and Jupiter. These space rocks, which are the size of sugar grains, get dragged by gravity towards Earth and Mars.

Sun

Spectacular Coronal Mass Ejection From Sunspot 1176 April 3, 2011

NASA twin STEREO spacecraft observed a spectacular coronal mass ejection launched from the vicinity of decaying sunspot 1176 on April 3rd around 0500 UT. The blast was not Earth directed. Nevertheless, there is a chance that the expanding cloud will deliver a glancing blow to Earth's magnetic field on or about April 6th. CME movies: STEREO-A, STEREO-B.


Meteor

Micrometeoroid? Small cracks found in three Southwest Airlines jets

Plane Holes
© BBC NewsTests on Southwest's 79 other 737-300s are expected to be completed by Tuesday evening

Small, sub-surface cracks have been found in three more Southwest Airlines planes like those thought to have caused another to develop a hole in its cabin roof mid-flight, officials say.

The National Transportation Safety Board said it had been informed there were additional crack indications in the lap joints on the Boeing 737-300s.

Nineteen other 737-300s showed no problems and will return to service.

The plane with the ruptured fuselage landed safely in Arizona on Friday.

Some of the 118 people on board the flight, which had just taken off from Phoenix, reported hearing a loud bang as a 1.5m-long gash appeared.

The hole caused a sudden drop in cabin pressure, forcing pilots to make a controlled descent from 10,485m (34,400ft) to a military base. No-one was seriously injured, though a flight attendant was slightly hurt.

Meteor

Sugar-grain sized meteorites rocked the climates of early Earth and Mars

Bombardments of 'micro-meteorites' on Earth and Mars four billion years ago may have caused the planets' climates to cool dramatically, hampering their ability to support life, according to research published today in the journal Geochimica et Cosmochimica Acta.

Scientists from Imperial College London studied the effects of the Late Heavy Bombardment (LHB), a period of time in the early Solar System when meteorite showers lasting around 100 million years barraged Earth and Mars. This bombardment discharged sulphur dioxide into the upper atmospheres of both planets and the researchers' analysis suggests that this may have had a catastrophic impact on their environments.

Micro-meteorites come from the rocky asteroid belt between Mars and Jupiter. These space rocks, which are the size of sugar grains, get dragged by gravity towards Earth and Mars. As they enter the planets' upper atmospheres, they heat up to temperatures of approximately 1000 degrees Celsius, releasing gases including sulphur dioxide. Sulphur dioxide in the atmosphere forms aerosols, consisting of solid and liquid particles, which deflect sunlight away from the surface, making planets cooler.

Meteor

Bullet or Micrometeoroid? FBI probes possible bullet hole in US Air plane

The FBI is investigating what might be a bullet hole, discovered in the side of a US Airways Group Inc (LCC.N) plane this week, the airline said on Wednesday.

The small hole in the Boeing (BA.N) 737-400 was found by a pilot on Monday at the Charlotte/Douglas International Airport in North Carolina.

"The pilot was doing his standard, pre-flight walk-around and noticed a small hole in the rear, left fuselage," said US Airways spokeswoman Michelle Mohr.

Camera

Suspected meteorite impact? Arizona, US: Plane makes emergency landing; hole reported

Passengers say blast heard on Southwest flight before safe emergency landing

Image
© via NBC newsThis picture was taken by a passenger aboard the Southwest flight as it prepared to make an emergency landing.
Yuma, Ariz. - A Southwest Airlines passenger jet flying from Phoenix to Sacramento, Calif., made an emergency landing in Yuma, Ariz., Friday after a hole opened up in the roof, officials said.

Flight 812, carrying 118 passengers, landed safely at Yuma Marine Corps Air Station/International Airport at 4:07 p.m. after experiencing "rapid decompression," the FAA said.

"Upon safely landing in Yuma, the flight crew discovered a hole in the top of the aircraft," Southwest said in a statement. "There are no reported customer injuries. One of the flight attendants, however, received a minor injury upon descent."

The cause of the decompression was not known, FAA spokesman Ian Gregor said. An FAA inspector from Phoenix was en route to Yuma.

Terrorism was not suspected because an FBI spokesman in Sacramento, Steve Dupre, said "it appears to be a mechanical issue."

Comment: In a separate report on this incident:




Meteor

NASA says spring is fireball season

What are the signs of spring? They are as familiar as a blooming Daffodil, a songbird at dawn, a surprising shaft of warmth from the afternoon sun. And, oh yes, don't forget the meteors. "Spring is fireball season," says Bill Cooke of NASA's Meteoroid Environment Center. "For reasons we don't fully understand, the rate of bright meteors climbs during the weeks around the vernal equinox."

Image
© NASAA spring fireball recorded by a NASA all-sky camera located at the Marshall Space Flight Center on March 16, 2009.

Click here to watch movie.

In other seasons, a person willing to watch the sky from dusk to dawn could expect to see around 10 random or "sporadic" fireballs. A fireball is a meteor brighter than the planet Venus. Earth is bombarded by them as our planet plows through the jetsam and flotsam of space--i.e., fragments of broken asteroids and decaying comets that litter the inner solar system. In spring, fireballs are more abundant. Their nightly rate mysteriously climbs 10% to 30%. "We've known about this phenomenon for more than 30 years," says Cooke. "It's not only fireballs that are affected. Meteorite falls--space rocks that actually hit the ground--are more common in spring as well1."

Researchers who study Earth's meteoroid environment have never come up with a satisfactory explanation for the extra fireballs. In fact, the more they think about it, the stranger it gets.

Meteor

Large meteor seen across New Zealand

A meteor that illuminated the sky with a brilliant blue and white light as it exploded over New Zealand last night was likely to have been the size of a desk.

Reports of a bright flashing light in the sky about 11pm were received from Auckland to as far south as Wellington while a sonic boom was heard by many people near Raglan.

Stardome Observatory astronomer and Auckland Astronomical Society president Grant Christie said that was likely caused by a large meteor, or bolide, at least 1m in diameter.

He compared it to another meteor which caused shockwaves and knocked people to the ground when it exploded at a height of 32kms over Wanganui.

Sun

Sunspot Profusion

Sunspots are popping up in many locations across the sun's surface, causing the sunspot number to surge above 100. Leading the way is behemoth active region 1176, shown here in a photo taken yesterday by Larry Alvarez of Flower Mound Texas.

Sunspot 1176
© Larry Alvarez
AR1176, the multi-cored ensemble at the bottom of the image, is dragging a pair of long magnetic filaments behind as it cuts aross the solar disk. Two more sunspots are visible in the active region's wake. The entire starscape spans more than 500,000 km from top to bottom--truly impressive.

"I call this picture Solar Rip," says Alvarez, "because it looks like a rip across the stellar surface." With so much happening on the sun, now is a good time to consider purchasing a solar telescope. Browse the links below for inspiration.

Blackbox

1811-12 New Madrid Earthquakes, A NEO Connection?

Great Comet of 1811
Partial projected path of the Great Comet of 1811 with locations of Burchell's comet and right triangle. Milky Way outlines are from Antonin Becvar's Atlas of the Heavens
The New Madrid seismic zone earthquakes of 1811-1812 may not have been caused by strictly run-of-the-mill seismic activity. This is a study into the possibility that some Near Earth Object (NEO), such as the "Great Comet of 1811", was an outside-the-box crustal stressor. If a NEO involvement is found, then some fear of the unknown about the timing of the next big one may come to be dispelled. See Earthquake Liquefaction Safety.

The following paragraph is extracted from the "Great Comet of 1811" article referred to above.

On November 4, [William J.] Burchell (near the Vaal River about 50 miles west of present day Kimberly, South Africa) wrote, "as I lay waiting for sleep, and amusing myself in observing the constellations above my head, I noticed a faint nebulous star of the third magnitude, which I had not been used to see in that part of the heavens. Looking at it more attentively, it appeared plainly to be a comet." He said it was located in the tail of Aquila and formed a right triangle with Alpha Cygni and Alpha Lyrae.