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Fire in the Sky


Asteroid Vesta Has Mountain Three Times as Tall as Everest

New view shows huge peak on Vesta's south polar region.

Vesta's south polar region, as seen in a digital model based on NASA images.
The asteroid 4 Vesta hosts a mountain three times as high as Mount Everest, seen in a new picture from NASA's Dawn spacecraft.

The unexpected peak rises from the center of a crater in the asteroid's south polar region. The mountain is about 13 miles (22 kilometers) high and spreads about 112 miles (180 kilometers) at its base.

By contrast, the biggest known mountain in the solar system, Mars's Olympus Mons, stands 16 miles (25 kilometers) high and spreads 374 miles (624 kilometers).


Did A Comet Cause Solar Explosion? Hardly, Ignorant Experts Say

A huge solar eruption that occurred right after a comet plunged into the sun was likely a coincidence, experts say.

The so-called "sungrazing" comet streaked toward the sun Saturday (Oct. 1) and disintegrated after getting too close. The sun then unleashed a massive eruption of solar plasma known as a coronal mass ejection, which can rocket through space at 3 million mph (5 million kph). But there's no reason to think the two dramatic events were related, scientists said.

"There still remains zero evidence for a link between sungrazing comets and coronal mass ejections (CMEs) that can't be better explained than by simple coincidence," Karl Battams of the U.S. Naval Research Laboratory wrote in a blog post Tuesday (Oct. 4). [Stunning Photos of Solar Flares & Sun Storms]

Solar astronomers with the sun-watching Solar and Heliospheric Observatory agreed.

"The question of whether a sungrazing comet can somehow trigger a coronal mass ejection is an intriguing one," SOHO scientists wrote in a website update this week. "So far, the feeling is that [the] apparent relationship between some comets and some mass ejections is simply one of coincidence."


A Meteorite Visits the Comettes

© Universe Today
This egg-sized meteorite broke through the roof of the Comette family.

When your last name is Comette, I'm sure the occasional astronomy-themed joke is never far away. But it's no joke that the Comette family living in Draveil, a suburb south of Paris, was paid a visit by a real extraterrestrial a couple of weeks ago - in the form of an 88-gram (3.5 oz.) meteorite that broke through their roof!

The Comettes were on vacation at the time, so didn't realize their house had been struck by a space rock until they noticed a leak in the roof. When they called in a roofer it was discovered that a thick tile had been completely broken through.

The meteorite was found wedged in insulation.

Mineral scientist Alain Carion investigated the meteorite and determined that it's an iron-rich chondrite, a 4.57-billion-year-old remnant of the early Solar System that most likely came from the main asteroid belt between the orbits of Mars and Jupiter. About 3/4 of all meteorites that have been observed landing on Earth are chondrites.


France: Meteorite believed to be more than 4bn years old smashes through roof of home on outskirts of Paris

© Nasa/EPA
The meteorite which hit the Comette family home is thought to have come from the asteroid belt between Mars and Jupiter.
When your name is Comette you may get used to jokes about rockets and space and planets. But French schoolboy Hugo Comette, 11, had the last laugh when of all the places, in all the countries on Earth, a piece of rock from outer space landed on his home.

An egg-sized meteorite believed to be 4.57bn years old smashed through the roof of the Comette family home on the outskirts of Paris some time over the summer when everyone was away on holiday.

And there the rock, blackened by its journey through Earth's atmosphere stayed, buried in the roof insulation, until Hugo's mother, civil servant Martine Comette, 32, noticed the roof was leaking and called out someone to fix it.


October 6, 2011: 50 reports of fireball sightings over Southeastern USA


Huge fireball spotted over Southeastern US on January 12 this year.
The American Meteor Society has so far received approximately 50 reports of a dazzling fireball over the southeastern USA including Florida, Georgia, Alabama and Mississippi. This event occurred near 8:40pm EDT (7:40pm CDT) Thursday evening October 6th. Of the reports received so far, green is the by far the most mentioned color. Vivid green fireballs are not unusual and in the case of slow meteors, such as this one, are usually caused by a particular element such as nickel or copper present in the meteor. The green color observed in swift fireballs are more likely caused by ionized oxygen caused by the passage of the meteor through the atmosphere. The average brightness reported by witnesses was near the light produced by a full moon.

A fireball is a meteor that is larger than normal. Most meteors are only the size of small pebbles. A meteor the size of a softball can produce light equivalent to the full moon for a short instant. The reason for this is the extreme velocity at which these objects strike the atmosphere. Even the slowest meteors are still traveling at 10 miles per SECOND, which is much faster than a speeding bullet. Fireballs occur every day over some parts of the Earth. It is rare though for an individual to see more than one or two per lifetime as they can also occur during the day or on a cloudy night. Observing during one of the major annual meteor showers can increase your chance of seeing another bright meteor.


Draconid Meteor Update

According to worldwide observers reporting to the International Meteor Organization, there was indeed an outburst of Draconid meteors on October 8th. Preliminary counts suggest a peak rate of 660 meteors per hour at 2010 UT (4:10 pm EDT).

Most Draconids in the outburst were faint, but not all. Göran Fredriksson photographed this fireball splitting the evening twilight over Örnsköldsvik, Sweden:

© Göran Fredriksson
Image Taken: Oct. 8, 2011
Location: Örnsköldsvik, Sweden
The meteor rate and overall faintness of the display was in good accord with predictions by leading forecasters such as Jeremie Vaubaillon of the Institute for Celestial Mechanics in France and analysts at NASA's Meteoroid Environment Office.


US: Four Orange Fireballs Cross Michigan Skies 'at a steady pace'

© Wikipedia.
As reported recently in New Jersey, four fireballs crossed Michigan skies on October 1, 2011, and the witness was able to capture all four on video.
A Michigan couple report "four consecutive fireballs" crossed the sky "traveling straight at a steady pace," according to October 2, 2011, testimony from the Mutual UFO Network (MUFON) witness reporting database.

The couple was driving home from dinner when they noticed the first "orange fireball rising up from the horizon."

"It was travelling almost perfectly from north to south," the witness stated. "All you could really see was the v-shaped plume of fire behind it."

The witness described the size of the object.and its path.

"If you extended your arm fully out in front of you, the plume appeared the size of your pinky fingernail. It was travelling straight, at a steady pace."

But then more fireballs were seen.

"What was really odd was that after it traversed the sky and went out of site, about 20 seconds later, another one appeared from the same origin, travelling the exact same path-pace as the first one. Even stranger, this happened a total of four times."


A Meteor Breaks Up in Earth's Atmosphere

NASA's Marshall Space Flight Center recorded a meteor breaking up in Earth's atmosphere on Sept. 30 at 8:37 p.m. EDT. Watch below.

Also, notice the star-like object moving slowly toward the upper middle of the screen. Orbiting 500 miles above Earth, it's the booster rocket that launched the Russian Cosmos 2219 intelligence satellite in 1992. The empty rocket body can get bright enough to be seen with the naked eye.

Comment: The same video in slow-motion from Space.com:


Triple Asteroid Crash Created Sudan Meteorites

© Peter Jenniskens (SETI Institute/NASA Ames)
The black fragment of Almahata Sitta meteorite number 15 shows up black against the lighter coloured rocks of the Nubian desert in northern Sudan.

Meteorites that fell over Sudan in 2008 could have come from a space rock that was formed by a triple-asteroid pileup - a collision between three different types of space rocks, a new study finds.

Scientists analyzed meteorite fragments that fell to Earth exactly three years ago today, on Oct. 7, 2008, and found that they contain an unusual mix of material from both primitive and evolved types of asteroids.

"Because falls of meteorites of different types are rare, the question of the origin of an asteroid harboring both primitive and evolved characteristics is a challenging and intriguing problem," study leader Julie Gayon-Markt, of the Observatoire de la Cote d'Azur in France, said in a statement.

The meteorites came from asteroid 2008 TC3, which impacted the Earth and rained more than 600 fragments across the Nubian Desert in Sudan. The meteorite fragments are collectively known as Almahata Sitta, which is Arabic for "Station Six," a train station between the Sudanese cities of Wadi Halfa and Khartoum, near where the fragments were found.

"Our recent studies of the dynamics and spectroscopy of asteroids in the main asteroid belt shed light on the origin of the Almahata Sitta fragments," Gayon-Markt said. "We show that the Nysa-Polana asteroid family, located in the inner main belt is a very good candidate for the origin of 2008 TC3."


Draconid Meteor Outburst October 8th

On October 8th, Earth will pass through a network of dusty filaments shed by Comet 21P/Giacobini-Zinner. Forecasters expect the encounter to produce anywhere from a few dozen to a thousand meteors per hour visible mainly over Europe, northern Africa and the Middle East. The meteors will stream from the northern constellation Draco--hence their name, the "Draconids."

Peak rates should occur between 1600 UT and 2200 UT (noon - 6 pm EDT) as Earth grazes a series of filaments nearly intersecting our planet's orbit. Analysts at the NASA Meteoroid Environment Office prepared this plot showing how the meteor rate is likely to vary:

© NASA Meteoroid Environment Office
If the maximum around 1900 UT reaches 1000 meteors per hour, the 2011 Draconids will be classified as a full-fledged meteor storm. The question is, will anyone see it? Bright moonlight over Europe, Africa and the Middle East will reduce the number of visible meteors 2- to 10-fold. The situation is even worse in North America where the shower occurs in broad daylight.