MessageToEagle.com - When the sun rose over Russia's Ural Mountains on Friday, Feb. 15th, many residents of
nearby Chelyabinsk already knew that a space rock was coming. Later that day, an asteroid named 2012 DA14 would pass
by Earth only 17,200 miles above Indonesia.
There was no danger of a collision, NASA assured the public.
Maybe that's why, when the morning sky lit up with a second sun and a shock wave shattered windows in hundreds
of buildings around Chelyabinsk, only a few people picking themselves off the ground figured it out right away.
This was not a crashing plane or a rocket attack. "It was a meteor strike—the most powerful since the Tunguska
event of 1908," says Bill Cooke of NASA's Meteoroid Environment Office.
In a coincidence that still has NASA experts shaking their heads, a small asteroid completely unrelated to
2012 DA14 struck Earth only hours before the publicized event. The impactor flew out of the blue, literally
from the direction of the sun where no telescope could see it, and took everyone by surprise.
"These are rare events and it is incredible to see them happening on the same day," says Paul Chodas of NASA's
near-Earth Object Program at JPL. Researchers have since pieced together what happened.
The most telling information came from a network of infrasound sensors operated by the Comprehensive Test Ban Treaty Organization
Their purpose is to monitor nuclear explosions. Infrasound is a type of very low-frequency sound wave
that only elephants and a few other animals can hear. It turns out that meteors entering Earth's atmosphere cause
ripples of infrasound to spread through the air of our planet.
By analyzing infrasound records, it is possible to learn how long a meteor was in the air, which direction it
traveled, and how much energy it unleashed.
The Russian meteor's infrasound signal was the strongest
ever detected by the CTBTO network.
The furthest station to record the sub-audible sound was 15,000km away in Antarctica. Western Ontario
Professor of Physics Peter Brown analyzed the data: "The asteroid was about 17 meters in diameter and
weighed approximately 10,000 metric tons," he reports.
Infrasonic waves from the meteor that broke up over Russia's Ural mountains on 15 Feb. 2013 were the largest ever recorded by the CTBTO's International
Monitoring System. Watch this animation and hear the infrasound recording of the meteor after it has been
filtered and the signal accelerated. Credit: CTBTO
"It struck Earth's atmosphere at 40,000 mph and broke apart about 12 to 15 miles above Earth's surface. The energy of
the resulting explosion exceeded 470 kilotons of TNT."
Click on image to enlarge
For comparison, the first atomic bombs produced only 15 to 20 kilotons. Based on the trajectory of the fireball,
analysts have also plotted its orbit.
"It came from the asteroid belt, about 2.5 times farther from the sun than
Earth," says Cooke. Comparing the orbit of the Russian meteor to that of 2012 DA14, Cooke has shown that there
is no connection between the two. "These are independent objects," he says.
"The fact that they reached Earth on the same day, one just a little closer than the other, appears to be
a complete coincidence." Infrasound records confirm that the meteor entered the atmosphere at a shallow angle
of about 20 degrees and lasted more than 30 seconds before it exploded. The loud report, which was heard and
felt for hundreds of miles, marked the beginning of a scientific scavenger hunt.
Thousands of fragments of the meteor are now scattered across the Ural countryside, and a small fraction have already
Preliminary reports, mainly communicated through the media, suggest that the asteroid was made mostly of stone with
a bit of iron—"in other words, a typical asteroid from beyond the orbit of Mars," says Cooke.
"There are millions more just like it." And that is something to think about as the cleanup in Chelyabinsk continues.
The Wandering Stars
In ancient civilizations, people pondered the meanings of the stars, watching for clues to their survival: the beginning of planting and
harvesting times, the seasons, and even portents of danger.
They soon noticed that certain stars didn't stay in place, but wandered amongst the fixed star field.
"The Most Profound Mystery In All Of Science" -
Little is known about this force and its its repulsive gravity, which is causing the expansion of the universe to accelerate.
The riddles of dark matter and cosmic inflation, along with dark energy, these are the three pillars of modern cosmological theory,"
and none of them can be explained with physics that we know," Michael Turner, director of the Kavli Institute for Cosmological Physics says.
Doesn't Secret Dark Matter Exist?
The more scientists study dark matter they know lesser and are not particularly optimistic about their results.
After completing this study, we know less about dark matter than we did before," said Matt Walker, of the Harvard-Smithsonian Center for Astrophysics.
A mysterious and still unknown substance is totally invisible in the Universe and reveals its presence only through its gravitational pull.
Mysteries Of A Dark Universe
Cosmology, the study of the universe as a whole, has been turned on its head by a stunning discovery that the universe is flying apart in all directions at an ever-increasing rate. Is the universe really as we think it should be? Or is nature somehow fooling us?
The astronomers whose data revealed this accelerating universe have been awarded the Nobel Prize for Physics.
Black Holes With No 'Table Manners' Eat Two Courses At Once!
It is still unknown how the supermassive black holes (SMBH) in galaxy centres accrete gas and grow.
Researchers from the University of Leicester (UK) and Monash University in Australia have investigated how some black holes got so big so fast that they are billions of times heavier than the sun.
Mercury Surprises Scientists
On March 17, MESSENGER (MErcury Surface, Space Environment, GEochemistry, and Ranging) completed its one-year primary mission, orbiting Mercury, capturing nearly 100,000 images, and recording data
that reveals new information about the planet's core, topography, and the mysterious radar bright material in the permanently shadowed areas near the poles.
Living Earth Simulator - Supercomputer Predicting The Future
In Douglas Adams book the Hitchhikers Guide to the Galaxy we encounter a machine called Deep Thought. It is the most powerful computer ever built. Deep Thought is capable of answering questions
concerning life, the Universe, and simply everything. Now scientists are planning to create a similar machine. It is called the Living Earth Simulator (LES).
Warp-Speed Planets Are Some Of The Fastest Objects In The Milky Way
Warped planets are some of the fastest objects in the Milky Way and they zoom through space near the speed of light.
Some years ago astronomers were astonished when they they found the first runaway star flying out of our Galaxy at a speed of 1.5 million miles per hour.
The discovery intrigued theorists, who wondered: If a star can get tossed outward at such an extreme velocity, could the same thing happen to planets?
Though the universe is filled with billions upon billions of stars, the discovery of a single variable star in 1923 altered the
course of modern astronomy. And, at least one famous astronomer of the time lamented that the discovery had shattered his world view.
Kepler Will Find Goldilocks Planet Within The Next Two Years
NASA's Kepler spacecraft is discovering a veritable avalanche of alien worlds. Recent finds include planets with double suns, massive
"super-Earths" and "hot Jupiters," and a miniature solar system.
The variety of planets circling distant suns is as wonderful as it is surprising.