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ROSAT - Re-Entry Information
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UPDATES
Final Report
The German Aerospace Agency DLR has issued a report including the time and location of the uncontrolled Re-Entry of the abandoned ROSAT Satellite. On Sunday, October 23, 2011 at 1:50 UTC, the spacecraft re-entered the atmosphere over the Bay of Bengal. It is not known wehter any debris reached Earth’s surface. This information was provided by evaluations of data that was provided by Germany and its international partners including the USA and the Space Surveillance Network.
Damage to property caused by ROSAT has not been reported. It is suspected that any components that survived the entry environment have splashed down in the Ocean away from populated areas. |
Photo: Fraunhofer FHR / DLR
ROSAT in Orbit on October 20, 2011 - 3 Days before Re-Entry
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Re-Entry Data
Final Orbit with Perigee Location
Image: Orbitron
Time: 1:50 UTC
Impact Zone: 7° N, 90° E - Bay of Bengal Ground Track and Re-Entry Location
Heavens Above
Groundtrack is accurate, Times are not.
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The decommissioned German X-Ray Observatory Satellite ROSAT is facing its uncontrolled Re-Entry in late October 2011. Launched in 1990 aboard a Delta II Rocket, the Spacecraft operated for 8.5 years and was shut down in 1999 sending it on an uncontrolled path towards Earth’s atmosphere. Over the last 12 years, the satellite has slowly closed in on upper levels of the atmosphere and is now experiencing exponentially increasing drag as time progresses.
When hitting the atmosphere at 17,000 miles per hour, the satellite will break apart and burn up to some extent in less than 10 Minutes. After that, its surviving components will be travelling at subsonic speeds and impact a short time later. Official analyses indicate that up to 3,500lbs of satellite components will survive the Re-Entry process reaching Earth at speeds of up to 280mph. 30 parts of the spacecraft have been identified that will likely make it to the surface. The largest pieces will be the mirror construction weighing up to 900lbs. Made of ceramic materials and coated with gold, the mirrors of the telescope assembly will withstand the extreme heat and significant loads experienced during re-entry. Other parts that are likely to survive entry include the spacecraft’s batteries, portions of the satellite’s central body and housings of avionics elements. Predicting the satellite’s re-entry time and location is difficult. Previous uncontrolled satellite re-entries, the latest being the UARS Satellite coming back to Earth on September 24 (Click here for details), have shown that predicting an exact time of entry is nearly impossible. As re-entry moves closer, more refined predictions will be made.
When hitting the atmosphere at 17,000 miles per hour, the satellite will break apart and burn up to some extent in less than 10 Minutes. After that, its surviving components will be travelling at subsonic speeds and impact a short time later. Official analyses indicate that up to 3,500lbs of satellite components will survive the Re-Entry process reaching Earth at speeds of up to 280mph. 30 parts of the spacecraft have been identified that will likely make it to the surface. The largest pieces will be the mirror construction weighing up to 900lbs. Made of ceramic materials and coated with gold, the mirrors of the telescope assembly will withstand the extreme heat and significant loads experienced during re-entry. Other parts that are likely to survive entry include the spacecraft’s batteries, portions of the satellite’s central body and housings of avionics elements. Predicting the satellite’s re-entry time and location is difficult. Previous uncontrolled satellite re-entries, the latest being the UARS Satellite coming back to Earth on September 24 (Click here for details), have shown that predicting an exact time of entry is nearly impossible. As re-entry moves closer, more refined predictions will be made.
Image: DLR
This map illustrates ROSAT's Ground Track by showing three chosen orbital paths of the spacecraft.
The satellite operated at an altitude of 585 to 565 Kilometers and its orbit has an inclination of 53°. The spacecraft could re-enter at any point of its orbit, putting all locations within 53.4 degrees northern and southern latitude into the danger zone. The debris footprint of this particular Satellite Re-Entry will be approximately 50 miles wide and several hundred miles long scattering debris of different sizes along the ground track of ROSAT.
The orbit of the abandoned satellite is being influenced by solar activity. Fluctuations in solar activity occur on a 11-year activity cycle, but smaller events like solar flares are not predictable until they happen. As the atmosphere is heated up by solar radiation, atmospheric drag increases as upper layers of the atmosphere expand, causing the satellite to decrease its orbital altitude faster. As Re-Entry gets closer, the satellite starts feeling traces of Earth’s gravity and interferes regularly with very thin portions of the atmosphere increasing its rate of descent. Vehicle attitude will play a large role in the final hours of its on-orbit life. At a certain point in its orbit, it will be low enough to dive into the dense atmosphere and slow down due to air resistance. The satellite will break apart and burn up to some extent.
 Photo Credit: NASA / ESA / Jesse Carpenter / Bill Moede Re-Entering Spacecraft without heat shield are usually good for a fairly impressive lightshow as parts burn up in the upper portion of the atmosphere before 20-40% of the satellites reach the ground. (image: ATV Re-Entry)
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During the re-entry phase, German scientists will work with the US Space Surveillance Network to evaluate orbital data concerned with the satellite’s Re-Entry. The Tracking and Imaging Radar located near Bonn, Germany will also keep track of ROSAT and its descent to improve re-entry predictions and calculations. NASA will monitor the spacecraft as its approaches its orbital decay. As Re-Entry approaches, more ground stations will start tracking and provide orbital information as part of the Inter-Agency Space Debris Coordination Committee (IADC).
Information wil be collected and analyzed at the European Satellite Operations Center (ESOC) in Darmstadt, Germany. It will then be forwarded to DLR and the IADC. Prediction accuracy for satellite re-entries has been an issue in the past and will continue to be an problem in the future. 6 months prior to entry, only a 10-week window during which the spacecraft comes back to Earth can be predicted. One week in advance, error margins are still 3 days. At T-24 hours to Re-Entry, predictions will still include a +/- 5-hour margin. Shortly before entry, a prediction will be issued on which orbit the satellite will fall back to Earth making it easier to exclude areas that will not be affected. ROSAT was initially supposed to hit the atmosphere in 2010, but a reduced maximum in solar activity slowed its descent. |
The risk to the public is low for this re-entry event. There is a 1 in 2,000 chance that someone located somewhere on Earth will be injured by ROSAT debris. Should life or property be affected by the crashing satellite, Germany will be held responsible and/or pay damages. Should the Satellite impact near a populated area, it is not recommended to approach any satellite debris or touch anything you think is a part of ROSAT. The Spacecraft did not have any radioactive components, but parts that survived re-entry usually show very sharp metal edges.
Previous Updates
October 23, 2011
The German ROSAT X-Ray Observatory Satellite has re-entered Earth's atmosphere on Sunday, October 23, 2011 between 1:45 and 2:15 UTC according the the German Aerospace Agency, DLR. At this time, it is uncertain wether ROSAT debris hit the surface or crashed into the Ocean. Launched in 1990, ROSAT spent the last 21 years and 4 months in orbit.
During the Entry time frame, the satellite passed over the Indian Ocean and parts of Asia (Myanmar and China). USSTRATCOM estimations indicate an Entry time of 1:50 UTC +/- 7 Minutes. This Entry time would put the satellite in the Indian Ocean away from China. Where exactly the debris hit will be announced later when more data has been analyzed.
Orbital Altitude - October 22: Click Here
During the Entry time frame, the satellite passed over the Indian Ocean and parts of Asia (Myanmar and China). USSTRATCOM estimations indicate an Entry time of 1:50 UTC +/- 7 Minutes. This Entry time would put the satellite in the Indian Ocean away from China. Where exactly the debris hit will be announced later when more data has been analyzed.
Orbital Altitude - October 22: Click Here
October 22, 2011
Orbit: 161km x 166km
Inclination: 53,0°
Period: 87.8min
Re-Entry Predictions:
DLR: October 22 23:30 UTC - October 23 5:00 UTC
Center for Orbital Debris/Re-Entry Studies: Oct 23, 11:12 UTC +/- 10 Hrs
USSTRATCOM: 2:34 UTC October 23 +/- 7 Hours
Impact Zone: 4.1° N, 252.1° E (USSTRATCOM)
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11294.06213865 .02180040 12087-4 46489-3 0 5828
2 20638 052.9671 155.3697 0004729 260.8864 099.1830 16.30009048194299
Orbital Altitude - October 22: Click Here
Orbit: 161km x 166km
Inclination: 53,0°
Period: 87.8min
Re-Entry Predictions:
DLR: October 22 23:30 UTC - October 23 5:00 UTC
Center for Orbital Debris/Re-Entry Studies: Oct 23, 11:12 UTC +/- 10 Hrs
USSTRATCOM: 2:34 UTC October 23 +/- 7 Hours
Impact Zone: 4.1° N, 252.1° E (USSTRATCOM)
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11294.06213865 .02180040 12087-4 46489-3 0 5828
2 20638 052.9671 155.3697 0004729 260.8864 099.1830 16.30009048194299
Orbital Altitude - October 22: Click Here
October 21, 2011
Orbit: 189km x 195km
Inclination: 53,0°
Period: 88.3min
Re-Entry Predictions:
DLR: October 22 18:00UTC - 23 12:00 UTC
Center for Orbital Debris/Re-Entry Studies: Oct 23, 13:24 UTC +/- 16 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11294.06213865 .02180040 12087-4 46489-3 0 5828
2 20638 052.9671 155.3697 0004729 260.8864 099.1830 16.30009048194299
Orbital Decay - October 21: Click Here
Orbit: 189km x 195km
Inclination: 53,0°
Period: 88.3min
Re-Entry Predictions:
DLR: October 22 18:00UTC - 23 12:00 UTC
Center for Orbital Debris/Re-Entry Studies: Oct 23, 13:24 UTC +/- 16 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11294.06213865 .02180040 12087-4 46489-3 0 5828
2 20638 052.9671 155.3697 0004729 260.8864 099.1830 16.30009048194299
Orbital Decay - October 21: Click Here
October 20, 2011
Orbit: 200km x 205km
Inclination: 53,0°
Period: 88.5min
Re-Entry Predictions:
DLR: October 22-23 +/- 24 Hours
Center for Orbital Debris/Re-Entry Studies: Oct 23, 10:33 UTC +/- 24 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11293.14139231 .01420620 11982-4 42935-3 0 5779
2 20638 052.9692 160.3303 0003782 218.3960 141.5828 16.26206056194141
Orbit: 200km x 205km
Inclination: 53,0°
Period: 88.5min
Re-Entry Predictions:
DLR: October 22-23 +/- 24 Hours
Center for Orbital Debris/Re-Entry Studies: Oct 23, 10:33 UTC +/- 24 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11293.14139231 .01420620 11982-4 42935-3 0 5779
2 20638 052.9692 160.3303 0003782 218.3960 141.5828 16.26206056194141
October 19, 2011
Orbit: 208km x 213km
Inclination: 53,0°
Period: 88.7min
Re-Entry Time: October 23 +/- 30 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11292.15727590 .01301969 11907-4 50084-3 0 5731
2 20638 052.9710 165.6127 0003800 238.7163 121.3428 16.23372604193989
Orbit: 208km x 213km
Inclination: 53,0°
Period: 88.7min
Re-Entry Time: October 23 +/- 30 Hours
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11292.15727590 .01301969 11907-4 50084-3 0 5731
2 20638 052.9710 165.6127 0003800 238.7163 121.3428 16.23372604193989
October 18, 2011
Orbit: 217km x 221km
Inclination: 53,0°
Period: 88.9min
Re-Entry Time: October 21-24 +/- 2 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11290.80152197 .00923309 11820-4 46263-3 0 568
5 2 20638 052.9743 172.8531 0003364 202.4478 157.6289 16.20096164193760
Orbit: 217km x 221km
Inclination: 53,0°
Period: 88.9min
Re-Entry Time: October 21-24 +/- 2 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11290.80152197 .00923309 11820-4 46263-3 0 568
5 2 20638 052.9743 172.8531 0003364 202.4478 157.6289 16.20096164193760
October 16, 2011
Orbit: 226km x 229km
Inclination: 53,0°
Period: 89.1min
Re-Entry Time: October 21-25 +/- 3 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11289.13438723 .00807130 42552-3 51498-3 0 5618
2 20638 052.9755 181.7207 0002838 196.7327 163.3657 16.17025365193499
Orbit: 226km x 229km
Inclination: 53,0°
Period: 89.1min
Re-Entry Time: October 21-25 +/- 3 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11289.13438723 .00807130 42552-3 51498-3 0 5618
2 20638 052.9755 181.7207 0002838 196.7327 163.3657 16.17025365193499
October 14, 2011
Orbit: 234km x 237km
Inclination: 53,0°
Period: 89.2min
Re-Entry Time: October 21-25 +/- 3 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11287.15482213 .00655664 25685-3 51467-3 0 5540
2 20638 052.9770 192.2015 0002534 162.2601 197.8551 16.14111705193177
Orbit: 234km x 237km
Inclination: 53,0°
Period: 89.2min
Re-Entry Time: October 21-25 +/- 3 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11287.15482213 .00655664 25685-3 51467-3 0 5540
2 20638 052.9770 192.2015 0002534 162.2601 197.8551 16.14111705193177
October 12, 2011
Orbit: 244km x 240km
Inclination: 53,0°
Period: 89.3min
Re-Entry Time: October 20-25 +/- 3 Days
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11285.23400570 .00513445 15001-3 47345-3 0 5476
2 20638 052.9774 202.3278 0002990 143.3475 216.7834 16.11764006192865
October 11, 2011
Orbit: 243km x 248km
Inclination: 53,0°
Period: 89.4min
Re-Entry Time: Late October
Impact Zone: No Prediction
Tracking TLE: (via Heavens-Above.com)
1 20638U 90049A 11283.86929140 .00513572 14689-3 51702-3 0 5432
2 20638 052.9788 209.5040 0003390 128.7952 231.3381 16.10449171192646
October 9, 2011
Orbit: 247km x 254km
Inclination: 53,0°
Period: 89.5min
Re-Entry Time: Late October/Early November
Impact Zone: No Prediction
October 4, 2011
Orbit: 258km x 264km
Inclination: 53,0°
Period: 89.7min
Re-Entry Time: Late October/Early November
Impact Zone: No Prediction
Tracking TLE: (via n2yo.com)
1 20638U 90049A 11277.21672769 .00334298 61734-4 48458-3 0 5227
2 20638 052.9786 244.3153 0004819 078.4486 281.7114 16.04740197191575
September 27, 2011
Orbit: 282km x 275km
Inclination: 53,0°
Period: 89.9min
Re-Entry Time: Early November
Impact Zone: No Prediction
Tracking TLE: (via n2yo.com)
1 20638U 90049A 11270.85672087 .00304555 50684-4 55227-3 0 5017
2 20638 052.9807 277.3683 0005334 063.7059 296.5788 16.00988537190555
Orbit: 282km x 275km
Inclination: 53,0°
Period: 89.9min
Re-Entry Time: Early November
Impact Zone: No Prediction
Tracking TLE: (via n2yo.com)
1 20638U 90049A 11270.85672087 .00304555 50684-4 55227-3 0 5017
2 20638 052.9807 277.3683 0005334 063.7059 296.5788 16.00988537190555
June 15, 2011
Orbital Altitude: 324km
Inclination: 53°
Re-Entry Time: October/November 2011
Orbital Altitude: 324km
Inclination: 53°
Re-Entry Time: October/November 2011
