From Greenbelt, Md., however, NASA's Gorkavyi and colleagues witnessed a never-before-seen view of the atmospheric aftermath of the explosion.
Model and satellite data show that four days after the bolide explosion, the faster, higher portion of the plume (red) had snaked its way entirely around the northern hemisphere and back to Chelyabinsk, Russia.
Image Credit: NASA's Goddard Space Flight Center Scientific Visualization
Shortly after dawn on Feb. 15, 2013, the meteor, or bolide, measuring 59 feet (18 meters) across and weighing 11,000 metric tons, screamed into Earth's atmosphere at 41,600 mph (18.6 kilometers per second). Burning from the friction with Earth's thin air, the space rock exploded 14.5 miles (23.3 kilometers) above Chelyabinsk.
The explosion released more than 30 times the energy from the atom bomb that destroyed Hiroshima. For comparison, the ground-impacting meteor that triggered mass extinctions, including the dinosaurs, measured about 6 miles (10 kilometers) across and released about 1 billion times the energy of the atom bomb.
ome of the surviving pieces of the Chelyabinsk bolide fell to the ground. But the explosion also deposited hundreds of tons of dust up in the stratosphere, allowing a NASA satellite to make unprecedented measurements of how the material formed a thin but cohesive and persistent stratospheric dust belt.
"We wanted to know if our satellite could detect the meteor dust," said Gorkavyi, of NASA's Goddard Space Flight Center in Greenbelt, Md., who led the study, which has been accepted for publication in the journal Geophysical Research Letters. "Indeed, we saw the formation of a new dust belt in Earth's stratosphere, and achieved the first space-based observation of the long-term evolution of a bolide plume."
Gorkavyi and colleagues combined a series of satellite measurements with atmospheric models to simulate how the plume from the bolide explosion evolved as the stratospheric jet stream carried it around the Northern Hemisphere.
About 3.5 hours after the initial explosion, the Ozone Mapping Profiling Suite instrument’s Limb Profiler on the NASA-NOAA Suomi National Polar-orbiting Partnership satellite detected the plume high in the atmosphere at an altitude of about 25 miles (40 kilometers), quickly moving east at about 190 mph (more than 300 kph).
The day after the explosion, the satellite detected the plume continuing its eastward flow in the jet and reaching the Aleutian Islands. Larger, heavier particles began to lose altitude and speed, while their smaller, lighter counterparts stayed aloft and retained speed – consistent with wind speed variations at the different altitudes.
By Feb. 19, four days after the explosion, the faster, higher portion of the plume had snaked its way entirely around the Northern Hemisphere and back to Chelyabinsk. But the plume’s evolution continued: At least three months later, a detectable belt of bolide dust persisted around the planet.
The scientists' model simulations, based on the initial Suomi NPP observations and knowledge about stratospheric circulation, confirmed the observed evolution of the plume, showing agreement in location and vertical structure.
"Thirty years ago, we could only state that the plume was embedded in the stratospheric jet stream," said Paul Newman, chief scientist for Goddard's Atmospheric Science Lab. "Today, our models allow us to precisely trace the bolide and understand its evolution as it moves around the globe."
The full implications of the study remain to be seen. Every day, about 30 metric tons of small material from space encounters Earth and is suspended high in the atmosphere. Even with the addition of the Chelyabinsk debris, the environment there remains relatively clean. Particles are small and sparse, in contrast to a stratospheric layer just below where abundant natural aerosols from volcanoes and other sources collect.
Still, with satellite technology now capable of more precisely measuring tiny atmospheric particles, scientists can embark on new studies in high-altitude atmospheric physics. How common are previously unobservable bolide events? How might this debris influence stratospheric and mesospheric clouds?
Scientists previously knew that debris from an exploded bolide could make it high into the atmosphere. In 2004, scientists on the ground in Antarctica made a single lidar observation of the plume from a 1,000-ton bolide.
"But now in the space age, with all of this technology, we can achieve a very different level of understanding of injection and evolution of meteor dust in atmosphere," Gorkavyi said. "Of course, the Chelyabinsk bolide is much smaller than the 'dinosaurs killer,' and this is good: We have the unique opportunity to safely study a potentially very dangerous type of event."Kathryn Hansen
Maria-Jose, Vinas Garcia | EurekAlert!
Filling the gap: High-latitude volcanic eruptions also have global impact
20.11.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences
Antarctic landscape insights keep ice loss forecasts on the radar
20.11.2017 | University of Edinburgh
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Physics and Astronomy
21.11.2017 | Life Sciences