Small object WT1190F. It will become the first chunk of space debris whose time and location of re-entry has been predicted. This image, acquired October 9, is from the University of Hawaii’s 2.2 meter telescope on Mauna Kea, Hawaii. Image via B. Bolin, R. Jedicke and M. Micheli.
Since 1957, when Sputnik 1 became Earth’s first artificial satellite, an unintended consequences of spaceflight has been a growing population of debris – space junk – orbiting Earth. Much of debris will eventually fall back into Earth’s atmosphere, and incinerate. But space junk does pose an increasing hazard, and, over the years, the uncontrolled reentry of large chunks of debris have caused some nail biting. This week, astronomers said that – for the first time – they’ve predicted just when and where a chunk of space debris will make its fiery return to Earth. They say the object temporarily designated as WT1190F – naturally nicknamed WTF – is due to Earth’s atmosphere on November 13, 2015 – at 1:20 a.m. EST (520 UTC) – over the Indian Ocean, in the vicinity of Sri Lanka.
Planetary astronomer Nick Moskovitz of Lowell Observatory in Flagstaff is one of many observers around the world helping to study object WT1190F. He told EarthSky:
This is the first time we have ever been able to predict something to the time and location of reentry.
With this information, other astronomers are able to point telescopes in that location and study the reentry.
We’ve also been able to narrow down the point of reentry to a fairly small location, which we know will be out over the ocean.
Experts estimate 20,000 objects larger a softball in Earth orbit. The estimated population of marble-sized particles is approximately 500,000. The number of particles smaller than marble-sized exceeds 100 million. Much of this debris is leftover fragments from spacecraft.
Astronomers said this week that WT1190F likely measures in the range of three to six feet (1-2 meters) in diameter. They said they think it might be a spent rocket body or other component from a spacecraft bound for the moon. The Catalina Sky Survey (CSS), based near Tucson, pinpointed object WT1190F on October 3. Later, they realized they’d spotted it twice before, in 2013.
Those combined observations let astronomers create a computer model of WT1190F’s orbit around Earth, and it let them predict when and where it’ll reenter.
Moskovitz said the debris and will probably burn up after entering the atmosphere. He said:
We don’t know what it is so we don’t know its shape and how it’s going to fragment. A piece of a solar panel, for instance, would behave differently than a booster tank. There is certainly the possibility that pieces could make it to the ground, though I think it’s unlikely.
He added:
We’re not 100% sure it’s artificial but we’re trying to solve that over the next couple of nights. Its orbit shows us that the object will undergo a close encounter with Earth this week, so we’ll be able to collect data on it.
Moskovitz said he plans to remotely observe the object with the Southern Astrophysical Research (SOAR) telescope in Chile, collecting images and spectral data. His colleagues in Italy and at the Jet Propulsion Laboratory in California will use data from his observations to refine the orbit, which will help pinpoint the place of entry on November 13.
Moskovitz said he hopes the team can then set up instruments to observe and collect data as the debris hurtles through the atmosphere at a speed of nearly seven miles per second (11 kps).
Artist’s concept of space debris surrounding Earth.
Bottom line: For the first time, astronomers say they know just when and where a chunk of space debris will strike Earth’s atmosphere. It’ll be November 13, 2015 – at 1:20 a.m. EST (520 UTC) – over the Indian Ocean, in the vicinity of Sri Lanka. WT1190F likely measures in the range of three to six feet (1-2 meters) in diameter. It’ll likely burn up on reentry.
from EarthSky http://ift.tt/1N8H1Nu
Small object WT1190F. It will become the first chunk of space debris whose time and location of re-entry has been predicted. This image, acquired October 9, is from the University of Hawaii’s 2.2 meter telescope on Mauna Kea, Hawaii. Image via B. Bolin, R. Jedicke and M. Micheli.
Since 1957, when Sputnik 1 became Earth’s first artificial satellite, an unintended consequences of spaceflight has been a growing population of debris – space junk – orbiting Earth. Much of debris will eventually fall back into Earth’s atmosphere, and incinerate. But space junk does pose an increasing hazard, and, over the years, the uncontrolled reentry of large chunks of debris have caused some nail biting. This week, astronomers said that – for the first time – they’ve predicted just when and where a chunk of space debris will make its fiery return to Earth. They say the object temporarily designated as WT1190F – naturally nicknamed WTF – is due to Earth’s atmosphere on November 13, 2015 – at 1:20 a.m. EST (520 UTC) – over the Indian Ocean, in the vicinity of Sri Lanka.
Planetary astronomer Nick Moskovitz of Lowell Observatory in Flagstaff is one of many observers around the world helping to study object WT1190F. He told EarthSky:
This is the first time we have ever been able to predict something to the time and location of reentry.
With this information, other astronomers are able to point telescopes in that location and study the reentry.
We’ve also been able to narrow down the point of reentry to a fairly small location, which we know will be out over the ocean.
Experts estimate 20,000 objects larger a softball in Earth orbit. The estimated population of marble-sized particles is approximately 500,000. The number of particles smaller than marble-sized exceeds 100 million. Much of this debris is leftover fragments from spacecraft.
Astronomers said this week that WT1190F likely measures in the range of three to six feet (1-2 meters) in diameter. They said they think it might be a spent rocket body or other component from a spacecraft bound for the moon. The Catalina Sky Survey (CSS), based near Tucson, pinpointed object WT1190F on October 3. Later, they realized they’d spotted it twice before, in 2013.
Those combined observations let astronomers create a computer model of WT1190F’s orbit around Earth, and it let them predict when and where it’ll reenter.
Moskovitz said the debris and will probably burn up after entering the atmosphere. He said:
We don’t know what it is so we don’t know its shape and how it’s going to fragment. A piece of a solar panel, for instance, would behave differently than a booster tank. There is certainly the possibility that pieces could make it to the ground, though I think it’s unlikely.
He added:
We’re not 100% sure it’s artificial but we’re trying to solve that over the next couple of nights. Its orbit shows us that the object will undergo a close encounter with Earth this week, so we’ll be able to collect data on it.
Moskovitz said he plans to remotely observe the object with the Southern Astrophysical Research (SOAR) telescope in Chile, collecting images and spectral data. His colleagues in Italy and at the Jet Propulsion Laboratory in California will use data from his observations to refine the orbit, which will help pinpoint the place of entry on November 13.
Moskovitz said he hopes the team can then set up instruments to observe and collect data as the debris hurtles through the atmosphere at a speed of nearly seven miles per second (11 kps).
Artist’s concept of space debris surrounding Earth.
Bottom line: For the first time, astronomers say they know just when and where a chunk of space debris will strike Earth’s atmosphere. It’ll be November 13, 2015 – at 1:20 a.m. EST (520 UTC) – over the Indian Ocean, in the vicinity of Sri Lanka. WT1190F likely measures in the range of three to six feet (1-2 meters) in diameter. It’ll likely burn up on reentry.
from EarthSky http://ift.tt/1N8H1Nu
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