Today's guest post was provided by Marco Langbroek, Leiden, NL, a keen back-yard astronomer and past contributor to ESA's ATV blog. He updates us on his efforts to track GOCE's (now famous) re-entry, which occurred on 11 November 2013. The intro below was provided by ESA's Holger Krag, from the Space Debris Office at ESOC. It's a pleasure for the professionals at ESA's Space Debris Office to note the strong support for re-entry analysis and, indeed, accurate and valid scientific participation, by 'citizen scientists' like Marco Langbroeck. Thank you Marco, for sharing your methods, results and enthusiasm. – H. Krag, ESA Space Debris Office In the evening of 10 November, near 19:54...
A very informative graphic provided by the ESA Space Debris Office showing the path taken by GOCE during its final destructive re-entry on 11 November 2013. The graphic summarizes the GOCE impact location as reported by the USA's JSpOC (JOint Space Operations Centre, at Vandenberg Airforce Base, California) at 56° S and 60° W, at 01:16 CET, Monday, 11 November, 2013, combined with the impact ground swath that was estimated by ESA's space debris experts using the SCARAB (Spacecraft Atmospheric Re-Entry and Aerothermal Break-up) software tool.
This special guest post was provided by Dr Eelco Doornbos, a researcher at the Delft University of Technology, The Netherlands. Dr Doornbos works on the faculty of Aerospace Engineering, and his work includes converting GOCE data into observations of air density and wind speed in the upper atmosphere. The foreword was provided by GOCE Mission Manager Dr Rune Floberghagen. The fact that GOCE kept functioning so well for nearly the entire de-orbiting phase opens exciting new science opportunities as illustrated by this blog entry. ESA will make sure all data relevant to the investigation of this phase are made readily available to the scientific community as soon as possible. Likewise, we will...
A fabulous photo acquired by Bill Chater of GOCE in The Falklands last night, at 21:20 local – about 01:20CET this morning, and posted in Twitter. Bill wrote: Driving southwards at dusk, it appeared with bright smoke trail and split in 2 before splitting again into more and going on north This would be the final view ever of ESA's GOCE satellite as it disintegrated and burned, some 80km high in the atmosphere. Good work, Bill! ESOC experts confirm - this is #GOCE! MT @Cheds23: We saw GOCE burn up from the Falklands at about 9.20pm last night. pic.twitter.com/DBYsV1n7KR — ESA (@esa) November 11, 2013
Update from ESA's Space Debris Office at ESOC, using information provided by ESA partners and the US tracking network. In close cooperation with USSTRATCOM, ESA's Space Debris Office gives the following estimated results for GOCE re-entry: The atmospheric interface at ~80 km altitude occurred, following a USSTRATCOM confirmation, at the latest, at 01:16 CET (00:16 UTC) 11 November 2013 This would correspond to a geographical location of approx. 60 degree West and 56 degree South, near the Falkland Islands This would put the main area over which any possible GOCE remnants fell to the southernmost regions of the Atlantic Ocean. View Larger Map
Close to 01:00 CET on Monday 11 November, ESA’s GOCE satellite reentered Earth’s atmosphere on a descending orbit pass that extended across Siberia, the western Pacific Ocean, the eastern Indian Ocean and Antarctica. As expected, the satellite disintegrated in the high atmosphere and no damage to property has been reported. Full text via ESA web
With the last pass, we're done! This post ends our coverage tonight, as there are no more communication passes expected with GOCE, hence we'll have no more updates from the mission control team. By the time you read this, the spacecraft's amazing flight will, most likely, have come to an end. Teams at ESA will continue waiting for tracking reports via ground radar systems, and, as soon as we get something, we will issue a formal PR in the web site.
Update from the Operations team at ESOC following the 23:42 CET pass: Contact with GOCE was made once again from the Troll station in Antarctica at 23:42 CET. The central computer temperature is at 80ºC and the battery is at 84ºC. At an altitude of less than 120 km, the spacecraft is – against expectations – still functional. Editor's Note: The Kármán line, or Karman line, lies at an altitude of 100 kilometres above Earth sea level, and commonly represents the boundary between the Earth's atmosphere and outer space.
This latest (and possibly final) forecast was just received from Prof Heiner Klinkrad, Head of the ESA Space Debris Office at ESOC. On a short pass over the Troll ground station that ended at 21:18 CET (20:18 UTC), while GOCE flew at an altitude of only 122 km, the satellite was still showing an amazing system performance, and dumped highly valuable data to the ground station. Using these data, that included very accurate navigation fixes along its trajectory, an orbit could be fitted that was used to forecast the re-entry of the spacecraft. Current estimates lead to a re-entry time window between 22:50 UTC on 10 November and 00:50 UTC on 11 November...
GOCE Operations Manager Christoph Steiger has just reported: Spacecraft still functioning nominally in Fine Pointing Mode, as seen in the last Troll pass just made at 22:16 CET (21:16 UTC). Temperature of central computer and battery now around 64 degC (some converters of the central computer already at 80 degC). Next possible visibility again over Troll at 23:42 CET (22:42 UTC).
RE-ENTRY FORECAST TIMES CORRECTED at 22:04 CET (1 hr later as expressed in CET - ED.) Via the GOCE mission operation's team and the ESOC Space Debris Office: Contact was made nominally at 20:50 CET at Antarctica’s Troll station. The temperature of the central computer and battery are around 54ºC. Next visibility is expected again over Troll at 22:16 CET. The new estimation for reentry of GOCE now predicts a time window between 23:30 and 01:30 CET.
This just in from Christoph Steiger, our GOCE Operations Manager: We've seen the spacecraft again over Kiruna at 19:56 CET (18:56 UTC), at an altitude of around 126 km. GOCE is still doing great; temperature of the central computer now above 50 degC. Next contact is expected at KSAT's Troll station in Antarctica at 20:50 CET (19:50 UTC).