ENVISAT declared dead in space

ESA declares end of mission for Envisat

Envisat

From the European Space Agency:
PR 15 2012 – Just weeks after celebrating its tenth year in orbit, communication with the Envisat satellite was suddenly lost on 8 April. Following rigorous attempts to re-establish contact and the investigation of failure scenarios, the end of the mission is being declared.
A team of engineers has spent the last month attempting to regain control of Envisat, investigating possible reasons for the problem.

Despite continuous commands sent from a widespread network of ground stations, there has been no reaction yet from the satellite.

As there were no signs of degradation before the loss of contact, the team has been collecting other information to help understand the satellite’s condition. These include images from ground radar and the French Pleiades satellite.

With this information, the team has gradually elaborated possible failure scenarios. One is the loss of the power regulator, blocking telemetry and telecommands.

Another scenario is a short circuit, triggering a ‘safe mode’ – a special mode ensuring Envisat’s survival. A second anomaly may have occurred during the transition to safe mode, leaving the satellite in an intermediate and unknown condition.

Although chances of recovering Envisat are extremely low, the investigation team will continue attempts to re-establish contact while considering failure scenarios for the next two months.

The outstanding performance of Envisat over the last decade led many to believe that it would be active for years to come, at least until the launch of the follow-on Sentinel missions.


ASAR image before loss of contact

Last image before loss of contact

However, Envisat had already operated for double its planned lifetime, making it well overdue for retirement.

With ten sophisticated sensors, Envisat has observed and monitored Earth’s land, atmosphere, oceans and ice caps during its ten-year lifetime, delivering over a thousand terabytes of data.

An estimated 2500 scientific publications so far have been based on this information, furthering our knowledge of the planet.

During those ten years, Envisat witnessed the gradual shrinking of Arctic sea ice and the regular opening of the polar shipping routes during summer months.

Together with other satellites, it monitored the global sea-level height and regional variations, as well as global sea-surface temperatures with a precision of a few tenths of a degree.

Years of Envisat data have led to a better understanding of ocean currents and chlorophyll concentrations.

In the atmosphere, the satellite observed air pollution increase in Asia and its stability in Europe and North America, and measured carbon dioxide and methane concentrations. Envisat also monitored the Antarctica ozone hole variations.

Over land, it mapped the speed of ice streams in Antarctica and Greenland. Its images were used regularly to update the global maps of land use, including the effects of deforestation.

Using its imaging radar, Envisat mapped ground displacements triggered by earthquakes and volcanic eruptions, improving understanding of tectonics and volcanic mechanisms.

Envisat provided crucial Earth observation data not only to scientists, but also to many operational services, such as monitoring floods and oil spills. Its data were used for supporting civil protection authorities in managing natural and man-made disasters.

Envisat has also contributed valuable information to the services within Europe’s Global Monitoring for Environmental Security (GMES) programme, paving the way for the next generation of satellites.

Now with the end of the mission, the launch of the upcoming GMES Sentinel satellites has become even more urgent to ensure the continuity of data to users, improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security.

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36 Responses to ENVISAT declared dead in space

  1. martinbrumby says:

    “During those ten years, Envisat witnessed the gradual shrinking of Arctic sea ice and the regular opening of the polar shipping routes during summer months.”

    But ven he start to show ze wrong finks, ve haff vays of stopping it making zees fery inconfenient obsurfashuns……….

  2. Richard111 says:

    “improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security.”
    What a marvelous record of success. The last sentence sent a chill down my back.

  3. corio37 says:

    Obviously when Arctic sea ice extent returned to its average level this month, that just blew its poor little electronic mind…

  4. Lawrie Ayres says:

    Funnily enough Martin I immediately thought the same thing. In Australia we are so accustomed to being lied to about sea level rise and temperature increases even when others say the opposite that we can no longer believe the CSIRO or the universities. The Envisat sea level data was something we could accept since the warmists tried to ignore it. And now it’s gone; how convenient just as the great scam was starting to clutch it’s chest and begin to totter. We really have become cynical but with justification.

  5. Jon says:

    It’s programmed to shut down if reality dare not to be UNFCCC conform?

  6. John Wright says:

    Yes, one does get cynical and I wonder what hitches to the upcoming Sentinel satellite launchings are in store. They’d better get them right.

  7. Eli Rabett says:

    Other than foolish comments (the ice will melt and pretty soon, most of that excess is well out of the Arctic circle) there is a hidden point here. Because satellites last a lot longer than their design life and there are constituencies that want the data, a lot of money is spent on the ground controlling the satellite, archiving the data, etc. The original budgets are based on the design life, so these extra costs squeeze funding for new and improved satellites. In fact, NASA has actually looked for organizations (like universities) who would take over these tasks on old satellites using some student labor, however, and it is a big however, universities are aware of the extra costs.

  8. Patrick says:

    Remember the Japanese satellite to finout where all the CO2 goes failed on launch? I smell a rat. Observations not conforming to models, how inconvenient.

    PS. At the Australian Climate Madness facebook page, the ANU e-mails have been released. When you read them you will quickly discover it was nothing short of a scare campaign in support of the Say Yes (To the carbon tax) Australia movement/rally.

  9. kadaka (KD Knoebel) says:

    Guess the Chinese “Asteroid Impact Defense” system test was a success. Time for the other big governments of the world to send China AID money, if we want China to “protect” us against sudden satellite loss.

    Question: Given the various worries such as solar events, space junk, small asteroid and micro-meteorite impacts, and assorted semi-random death rays, could we make do about as we are now with no-satellite surface-based communications? I know there are frequencies that “bounce” around the ionosphere, as with shortwave radio. Can we get enough bandwidth? Could we incorporate position-holding floating repeater stations, held aloft by the equivalent of weather balloons and powered by solar or other energy, placed at “safe” locations above continents and clouds? Such have been considered in the past, but we’ve gotten better at miniaturization thus the payloads will be smaller thus the concept more feasible nowadays.

  10. Kelvin Vaughan says:

    We all got to go one day, satellites and all.

  11. Myrrh says:

    “the launch of the upcoming GMES Sentinel satellites has become even more urgent to ensure … civil security.”

    So exactly what was it doing in this regard? Are we all free from surveillance now…?

  12. E.M.Smith says:

    @Kadaka:

    There are still lots of cables under the ocean. IIRC the major internet connection to Asia departs from somewhere near Seattle.

    Don’t know the relative volumes of satellite vs cable, but if you care about latency, cable is much better.

  13. Dave says:

    When it started to report that sea level was dropping, it was murdered!

  14. DocMartyn says:

    “Well done, good and faithful servant; you have been faithful over a few things, I will make you ruler over many things”

    Matthew 25:23

  15. Kaboom says:

    I’m not one for conspiracy theories but it does touch upon a nerve that it would fail at a time when replacements are not ready and increasingly inconvenient data for the AGW narrative could be gathered.

  16. Jame Sexton says:

    Kaboom says:
    May 10, 2012 at 5:04 am

    I’m not one for conspiracy theories but it does touch upon a nerve that it would fail at a time when replacements are not ready and increasingly inconvenient data for the AGW narrative could be gathered.
    ====================================
    Lol, that’s not the only coincidental bit of timing either. They dramatically adjusted Envisat’s sea level measurements up….. and then we never heard from Envisat again. I think Dave is right on this one.

  17. Smokey says:

    Kaboom has a point. The last Envisat sea level data.

    Plenty of folks were happy to see Envisat’s demise because of this.

  18. Alan the Brit says:

    Richard111 says:
    May 9, 2012 at 11:21 pm
    “improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security.”
    What a marvelous record of success. The last sentence sent a chill down my back.

    Pocket Oxford English Dictionary, 1925: Sentinel, sentry, soldier posted to keep guard, watch, or duty. Trouble is something like this is a double-edged sword, like a wall, it may keep people out, but it also keeps people in! ;-) Naaah, the Peoples’ Democratic Republic of the EU would never do anything like that, they would never sideline democracy where member state guvments have no real power, only the power to cede more power to the Commission, an unelected, undemocratic, unaccountable, & unsackable bunch of overprivilaged & obscenely overpaid fat-cat pensioned useless worthless lard-arsed bureaucrats (I’m not biased, honest) who make the laws & make peoples lives a misery with their rules & regulations, destroy the UK economy with its econutty silly dystopian socialist whims & desires of control, naaah, they wouldn’t, wouldn’t they??? Now, where did I put that dvd of V for Vendetta?

  19. Martin C says:

    Eli Rabett says:
    May 10, 2012 at 12:32 am

    Sounds logical to me – then again, why not use some of the ‘global warming’ funding, all those billions that are out there, to use for the universities to help with the satellite data, and all . . . ?

  20. Laurie Bowen (the troll) says:

    And with this just out . . . .

    “Divine Intervention is now taking place on a dramatic, unprecedented basis — worldwide.

    This is causing a complete, systematic failure of the war machine on every level.

    Guns will not fire. Radio and satellite communications systems are breaking down — right when they are needed most. Airplanes and tanks will not start. Bombs will not deploy.

    Even more surprisingly, dozens of underground bases have now been completely emptied out — beginning on August 23, 2011.

    This is terrifying to the occult Cabal that has seized control of much of the financial system, as well as the governing and judiciary bodies of several of the top nations in the world.

    In my epic work “Financial Tyranny” I outline the problems we face, and who is responsible for them — with an incredible amount of supporting evidence.”

    http://divinecosmos.com/start-here/davids-blog/1054-divineintervention?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+DavidWilcockBlog+%28David+Wilcock+Newsletter%29

  21. Erny72 says:

    Conspiracy theorists; isn’t it far more likely that an old satellite, operating beyond its design life was adversely affected by the recent solar activity? And that the lack of immediate replacement reflects EUssr bureaucratic planning failing to follow the seven P’s principle, rather than some sinister plot to remove a source of scientific information?

  22. u.k.(us) says:

    From the European Space Agency:
    “Now with the end of the mission, the launch of the upcoming GMES Sentinel satellites has become even more urgent to ensure the continuity of data to users, improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security.”
    =================
    Wow
    “ensure civil security”
    Not sure what that means, but I guess hope springs eternal.

  23. DesertYote says:

    Erny72 says:
    May 10, 2012 at 9:11 am

    Conspiracy theorists; isn’t it far more likely that an old satellite, operating beyond its design life was adversely affected by the recent solar activity? And that the lack of immediate replacement reflects EUssr bureaucratic planning failing to follow the seven P’s principle, rather than some sinister plot to remove a source of scientific information?
    #

    No. Bird was not old, solar activity is insignificant and would not have effected proper engineered electronics. Greenies deliberately turning off the satellite vs. just complete ESA incompetence. If just ESA incompetence, its because its run by greenies more interested in the agenda then science, so either way ….

  24. Trevor says:

    Very unprofessional writing. Look at the first sentence of the press release. The way it’s worded, it’s not Envisat that just celebrated it’s tenth year in orbit, but COMMUNICATION with Envisat.

  25. John Blake says:

    Having realized to what misuse AGW Catastrophists typically applied its hard-earned data, Envisat has probably perished of a broken heart.

  26. _Jim says:

    DesertYote says: May 10, 2012 at 11:35 am


    No. Bird was not old,

    … whereas the lead-post story says:

    The outstanding performance of Envisat over the last decade led many to believe that it would be active for years to come, at least until the launch of the follow-on Sentinel missions.

    However, Envisat had already operated for double its planned lifetime, making it well overdue for retirement.

    “Old?”; It would indeed seem so …

    .

  27. _Jim says:

    kadaka (KD Knoebel) says on May 10, 2012 at 1:00 am

    Question: Given the various worries such as solar events, space junk, small asteroid and micro-meteorite impacts, and assorted semi-random death rays, could we make do about as we are now with no-satellite surface-based communications? I know there are frequencies that “bounce” around the ionosphere, as with shortwave radio. Can we get enough bandwidth? …

    This isn’t 1950 (or even 1960 or 1970); there is more than sufficient capacity on fiber (fibre ?) running around the world, not to mention the lower latency (spell that: “propagation delay time”) mentioned by ‘Echo’ ‘Mike’ Smith above.

    Geostationary satellite latency and time delay
    http://www.satsig.net/latency.htm

    If you are located on the equator and are communicating with a satellite directly overhead then the total distance (up and down again) is nearly 72,000 km so the time delay is 240 ms [milliseconds].

    A satellite is visible from a little less than one third of the earth’s surface and if you are located at the edge of this area the satellite appears to be just above the horizon. … The distance to the satellite is greater and for earth stations at the extreme edge of the coverage area, the [one-way] distance to the satellite is approx 41,756 km. If you were to communicate with another similarly located site, the total [up and down] distance is nearly 84,000 km so the end to end delay is almost 280 ms …

    “The Internet’s undersea world” courtesy of The Guardian (map may be a few years old):
    http://image.guardian.co.uk/sys-images/Technology/Pix/pictures/2008/02/01/SeaCableHi.jpg

    Modern history – Optical telephone cables
    http://en.wikipedia.org/wiki/Submarine_communications_cable#Modern_history

    As of 2012 operators had “successfully demonstrated long-term, error-free transmission at 100 Gbps across Atlantic Ocean” routes of up to 6000 km, meaning a typical cable can move tens of terabits per second overseas. Speeds improved rapidly in the last few years, with 40 Gbit/s having been offered on that route only three years earlier in August 2009.

    ‘Novel’ technique of ‘laying cable’ off the coast of Africa (as a means to prevent disruptions thta land-based circuits might otherwise see due to … ‘political complications’):
    http://en.wikipedia.org/wiki/EASSy_(cable_system)

    Dated doc on “SUBMARINE CABLE INFRASTRUCTURE” covering some data capacities circa the year 2000 with extrapolation going forward:
    http://www.rand.org/content/dam/rand/pubs/monograph_reports/MR1395/MR1395.appi.pdf

    .

  28. DesertYote says:

    _Jim
    May 10, 2012 at 12:45 pm

    BZZT! Wrong answer. 10 year life is a joke despite the lefty spin of the article. BTW, 15 years in aerospace, most working on NASA satellites. The projects I worked on, other than the one that was smeared across the surface of Mars, are still working just fine. In fact, some of the stuff my dad worked on 15 years before is still working.

    “Outstanding Performance” sounds like a phrase from the performance review of a sycophant.

  29. Blade says:

    However, Envisat had already operated for double its planned lifetime, making it well overdue for retirement.

    I’m not a big fan of this kind of statement.

    Setting low expectations has become the SOP of the post-modern big-spending pseudo-Scientific era. And this applies to many fields that have nothing at all to do with Science as well.

    I for one have high expectations for things purchased with my tax dollars.

  30. _Jim says:

    DesertYote says:
    May 10, 2012 at 1:39 pm

    BZZT! Wrong answer. 10 year life is a joke despite …

    Friend, I still have ‘gear’ (albeit not space qualified nor operating under ‘harsh’ conditions such as space) first manufactured (fabricated, including active semiconductors/transistors) in the 1960’s … so, ten years, ten schmeeers …. normally fans (‘mechanicals’) and electrolytic (power supply) caps ‘give out’ first but as you know in space different ‘things’ can happen (you recall the dendritic tin whisker growth [1] that has taken out birds in past years like Galaxy IV satellite in 1998? I joined an employer shortly after that event in ’98 … they had *just* engaged in a major ‘all-hands on-deck’ scramble to re-orient all their earth-station antennas at the *many* terrestrial sites they hd in their large system across the contiguous-48 to a different bird in the satellite belt after that outage.)

    Space, being a somewhat harsher environment than a ‘radio hut’/environmental building coupled with zero-G can do strange things not to mention the zero bar atmosphere and effects that can have on lubricants. As you should know, the ‘lifetimes’ are also negotiated figures; different parties (from the insurer, the platform contractor/integrator, individual instrument manufacturers, etc) have different interests in that ‘lifetime’ number.

    Now, the capper: What has been the mean life on our GOES series of satellites? And what kind of distribution in ‘lifetimes’ have we seen across the series?

    .
    .

    [1] http://nepp.nasa.gov/whisker/background/index.htm

    .

  31. _Jim says:

    DesertYote says:
    May 10, 2012 at 1:39 pm

    _Jim
    May 10, 2012 at 12:45 pm

    BZZT! Wrong answer. 10 year life is a joke despite …

    Despite a steadfast assertion to the contrary, I’m finding multiple cites of the “5 year” lifetime in multiple technical ‘white papers’, such as here:

    ENVISAT ASAR – Design & Performance with a View to the Future
    by Michael Hutchinson, Michael D. Gibbons
    http://ftp.rta.nato.int/public//PubFullText/RTO/MP/RTO-MP-061///MP-061-34.pdf

    Architecture: The ASAR [on Envisat] instrument consists of two main elements, the Central Electronics Sub-Assembly (CESA) and the Antenna Sub-Assembly (ASA). The whole being designed with a fully redundant electronics systems architecture and a life requirement of 5 years in the Low Earth Polar Orbit environment.

    (bolding mine) and:

    Precision Non-Conservative Force Modelling For Low Earth Orbiting Spacecraft
    by Anthony John Sibthorpe
    http://www-research.cege.ucl.ac.uk/gnrg/PhD/Ant_Sibthorpe_PhD.pdf

    Where we find:

    5.5. Bus Internal Heat Flow Modelling – Qrates
    5.5.1. Qrate Retrieval

    Thermal re-radiation (TRR) for bus sections and solar arrays of spacecraft has long been known to contribute significantly to the non-conservative forces affecting Earth orbiting satellites. However, the emission of heat from the interior of the spacecraft has largely been ignored.

    This is probably due to the fact that vents and radiators are commonly positioned symmetrically across satellite surfaces (e.g. GPS, JASON), and so any thermal forces arising have been thought to cancel each other out.

    As can be seen from Figure 5-13, ENVISAT’s radiator nodes are clearly not symmetrically positioned over the satellite’s surface, a situation likely to result in a net thermal force; this is due to the requirement to position all of ENVISAT’s scientific hardware in such a tightly controlled space (Robson, 2004, Astrium, pers. comm.). EADS Astrium (UK) was responsible for the thermal design of ENVISAT’s internal components, and has extremely sophisticated beginning-of-life (BOL) and end-of-life (EOL) thermal models for this satellite’s bus (their most complex to date).

    What then ensues are calculations (and related) which also consider the decreasing fuel load (a ‘heat sink’ locally and thermal conductor internal to the satellite) and increasing output heat-load internally that this low earth-orbit (LEO, 800 km) satellite was designed at some ‘level’ or magnitude to endure.

    There is also a reference to the following for analytical purposes:

    BOL: Friday March 1, 2002. At 01:07.59
    EOL: Thursday March 1, 2007. At 01:08.00

    the difference being the assumed 5 year lifetime …

    .

  32. DesertYote says:

    _Jim says:
    May 10, 2012 at 3:35 pm
    ###

    Ok so what? The Europeans don’t know how to build satellites. We already knew that. The bird was designed for 5 years and it only lasted twice that? I’m sorry, but that is not impressive by US standards. Meeting expectations is NOT something worthy of praise. That people think it is, is just more indication of the destruction to our society caused by the pervasiveness of a Marxist world-view.

    BTW, one of the papers was written by someone who clearly has as much knowledge of satellite design as Hanson has about atmospheric physics. He made a statement that is blatantly wrong. Big FAIL!

  33. DesertYote says:

    _Jim says:
    May 10, 2012 at 2:17 pm

    Space, being a somewhat harsher environment than a ‘radio hut’/environmental building coupled with zero-G can do strange things not to mention the zero bar atmosphere and effects that can have on lubricants. As you should know, the ‘lifetimes’ are also negotiated figures; different parties (from the insurer, the platform contractor/integrator, individual instrument manufacturers, etc) have different interests in that ‘lifetime’ number.

    ###

    Guess you did not get the fact that I spent 15 years of my life with the qualification of space hardware, including stuff that is now on running around on Mars. You also mentioned the Purple Plague. Hell, there was absolutely no excuse for hardware to succumb to a problem that had been well known and characterized for 30 YEARS! I know because my dad was one of the guys who was involved with characterizing it. If you want to talk about strange failure modes, talk about phosphor-glass passivisation, not some that could have been prevented with a little pit of silver. And GOES suffers, like everything else from the drive towards the mediocrity that the lefties love so much. “Cheaper, faster, better”, yay right! NASA lost all of its good engineers 20 years ago when the Democrats made it a lefty only shop. I worked on GOES 9. The stuff my company did is still working just fine. It was designed for three, used for over 10, and placed in a parking orbit while STILL functional. The main problem that it had was with parts made by major lefty donor Loral( We sell secrets to the chinese) Space Systems. My company which had one field failure 40 years (due to die NASA bought us) was driven out of business because we were not lefties.

  34. mojo says:

    In space, nobody can “Press F1 to continue”…

  35. Brian H says:

    DY;
    Yeah, Lefty technology is a de facto oxymoron. Unfortunately, it produces huge collateral damage when employed.

  36. gymnosperm says:

    Is anyone really surprised that tropospheric temperatures would rise when there are indications that sea surface temperatures are rising? Acknowledging the problems with Levitus et al, after three decades of atmospheric warming it seems unsurprising that the oceans, with three orders of magnitude more heat capacity would lag the atmosphere in any change of trend. Yet it seems another ridiculous material property of H2O is the inability of the liquid state to absorb long wave photons much deeper than the wavelength, i.e. a few angstroms.
     
    The bottom line, within the rather narrow confines of our understanding, is that heat exchange between the ocean and the atmosphere is pretty much a one way street, with the ocean almost always warming the atmosphere.

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