UPDATE: NASA program debris Program Office at the Johnson Space Center, Houston, has announced that from ICESat spacecraft debris fell in the Barents Sea to the development of the Earth, it is added to our catalogue on Monday, 30, is approximately 5 a.m. EDT.
One of NASA's sentinels is expected to return to Earth evolved in a few days. The Agency's Ice Cloud and elevation satellite (ICESat) very scientific mission country completed earlier this year.NASA, for the purposes of calculating the satellite orbit last month, and then click disabled in the context of the preparation of the spacecraft re-entry. it is estimated that the satellite of the Earth's atmosphere again and to a large extent, or disc information on 29 August.
ICESat was introduced in January 2003 than three years from the date on which the operation is intended to provide information on Science, for a period of five years. It was the first kind – specifically in the fields within its mission, to consider the Earth's polar regions in space laser Altimeter Geoscience Laser Altimeter System is called or GLAS.
ICESat's lasting legacy is its effect on the ice sheet and glacier Dynamics Operation has led to a better understanding of. measurements must be carried out on the Greenland and Antarctic ice sheets, polar sea ice thickness, vegetation canopy heights and clouds and aerosols mass changes to scientific developments. ICESat data allows researchers to identify the network of Lakes of Antarctic ice below the table. ICESat was introduced new features, techniques and methods, such as the measurement of sea ice freeboard – or the amount of ice and snow, which protrudes above the surface of the ocean-sea ice thickness for evaluation.
"There is a huge scientific ICESat has been a success," said Jay Zwally, ICESat's project scientist AT NASA's Goddard Space Flight Center, Greenbelt, MD, "it has given details of how the Earth's polar ice masses are about to change and global warming, Government policy decisions where necessary, in particular, ICESat data showed that Arctic sea ice has been rapidly thinning, which contains important information on how soon Lamers may be mostly ice free in summer, most of the card. It is also shown how much ice is the Greenland sea level rise will lose and financing. ICESat gives you the ability to now know that the Antarctic ice-sheet does not lose so much ice, such as other studies have shown. "
The End of era
Orbit and 15 laser operations campaigns ICESat's seven years from the date on which the operation ended February 2010 in science a priority instrument failure.Because the spacecraft was operating condition, NASA's Science Mission Directorate approve proposals process engineering tests must be carried out using the ICESat.These trials were carried out, June 20. NASA's Earth Science Division authorized then proceeded to review the operation of the ICESat. decommissioning operations directed, within the Agency, the ICESat will be turned off for this August.
The operation of the flight controllers began ICESat's propulsion thrusters when starting the system, reduce the orbit on 23 June. Engine Ammuntoja ended on 14 July to safely reduce the spacecraft orbit 125 is located (200 km) from the lowest point of the ground. Orbit must, of course, decayed. ICESat was successfully closed from 14. development activities All remaining fuel spacecraft now depleted and atmospheric Drag slowly is degrading ICESat's orbit, until the spacecraft re-enters the Earth's atmosphere.
Earth Science mission Operations office notification summary of achievement:
"The ICESat mission operations team is working tirelessly thanked the exceptional performance over the last eleven years (four years of preparation and of the activities of seven years), overcoming the obstacles to the operation in the first years of the multiple and exclude the operation of sound set of orbital maneuvers before definitive cessation.At the end of the operation of the positive control is maintained the right to display the work, which went to the design, construction, qualification, starting and operating a successful operation, such as from ICESat and quality. "
Return to Planet Earth
The majority of ICESat store atmosphere, re-entry period. total mass of the spacecraft (about 2000 lbs.), and only a small% achieved on the surface.Some parts of the spacecraft weighing together about 200 pounds is expected to survive re-entry.This outstanding balances on Earth who come from injury risk is estimated to be extremely low.
ICESat is not designed to carry out a controlled re-entry and cannot be applied to a specific location on Earth.ICESat circles the Earth pole pole, so alive residuals can extract from almost anywhere on Earth.Due to natural variability in the near-Earth environment, the exact location where the spacecraft debris again cannot be forecast.u.s.Space Surveillance network will follow closely the orbit of the last days of ICESat and continue shall submit periodically to the projections on the re-entry of time, and location. NASA program debris Program office shall issue the re-entry of the estimations are based on the data.
NASA and the international standards from reaching the Earth's atmospheric space objects do not need to be controlled re-entry requirements and guidelines, but are caused by the remnants of surviving re-entry of the highest risk.
Nicholas l. Johnson, NASA, the program for the residues in NASA Johnson Space Center Houston, said "ICESat group is committed to ensure that the risk of the spacecraft and other spacecraft orbital debris as a source of potential future marvelous work".
The Future looks Bright
At the end of the operation of ICESat, NASA observations of the Earth's polar regions ICESat mission to an end., and the National Research Council Decadal Survey in the future, NASA Earth science missions in advance in accordance with NASA has begun development of ICESat-2-planned in 2015. ICESat-2 continue their predecessor in business, science, and our knowledge of the legacy of the Earth's dynamic polar regions with new and advanced technology.
Operation in the air, Ice Bridge started in 2009 is the largest in the investigation of the Earth's polar ice ever flown. Operation is intended to fill the gap between the information partially and ICESat ICESat-2-satellite instruments NASA aircraft tutkimuskohteilla quickly change to produce an unprecedented view of the Arctic and Antarctic ice sheets, sea ice and ice shelves in the next five years. aircraft satellite broad and consistent coverage in combination with a more complete understanding of the targeted information contribute to global climate change, will help researchers better forecasting and may not be made in response to the future.
Related links
› ICESat Re-Entry frequently asked questions
› ICESat Noteable Moments in Science
› ICESat Notable Moments Science image gallery (Flickr)
› ICESat Video Highlights
› Activity Ice Bridge
› Decadal Survey – NASA Science challenges
› Antarctica and Ice access
› NASA provides new perspectives, the Earth's changing Ice sheets
› NASA Satellite reveals Dramatic thinning the Ice
› Map of the European Social Fund, active Lakes below the Antarctic Ice
› NASA Ice Polar Satellite Maps deep were the impressions made on my thinning
› ICESat on Twitter
Sarah DeWitt
NASA's Goddard Space Flight Center
This text from:
http://www.nasa.gov/mission_pages/icesat/icesat-end.html
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