August 15, 2013
Tracking Russian Meteor Debris Field Offers Insight Into Future Events
[WATCH VIDEO: Meteor Debris Around The World In Four Days]
Brett Smith for redOrbit.com - Your Universe Online
Using satellite data and computer models, NASA scientists were able to track and study the debris of the meteor that exploded over Chelyabinsk, Russia in February, giving them a better picture of how similar future events might affect the Earth’s atmosphere.
Just after sunrise on February 15, a meteor measuring about 59 feet across and weighing over 12,000 tons exploded 14.5 miles above Chelyabinsk with a force approximately 30 times the energy of the Hiroshima atomic bomb. While some pieces of the meteor fell to the ground, the explosion also sent hundreds of tons of dust into the Earth’s stratosphere.
Approximately 3.5 hours after the explosion, the NASA-NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) satellite was able to detect the resulting dust plume about 25 miles above the Earth and moving east at about 190 mph.
"We wanted to know if our satellite could detect the meteor dust," said Nick Gorkavyi, an atmospheric physicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland and former Chelyabinsk resident. "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 (meteor) plume."
One day after the explosion, the satellite watched as the plume continued eastward, eventually reaching Alaska’s Aleutian Islands. While some of the larger, heavier particles began to lose altitude, the smaller, lighter bits of dust stayed aloft and adrift – matching wind speed variations at the different altitudes.
Four days after the explosion, higher portions of the dust plume had wrapped around the Northern Hemisphere and back to Chelyabinsk and at least three months later, a detectable belt of dust could still be found around the planet.
In a report, which was published in the journal Geophysical Research Letters, the NASA scientists modeled simulations, based on weather conditions and initial Suomi NPP data. The simulations confirmed the observed progression of the plume, in both location and vertical structure, the study said.
"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 dust from] the [meteor] and understand its evolution as it moves around the globe."
Study researchers suggested that their findings could allow for more precise measuring of tiny atmospheric particles, enabling new studies on high-altitude atmospheric physics. Tons of small material from space encounter Earth on a daily basis and are suspended in the upper atmosphere. While the layer where the dust from the Chelyabinsk resides is kept fairly clean, the stratospheric layer just below collects natural aerosols from volcanoes and other sources.
"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 (meteor) 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."