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Monster European Environmental Satellite
andygood writes: "Spaceflight Now has this article about the 'Mother of All Earth Observation Satellites' which will be launched by Europe in early 2002. This thing is the size of a juggernaut and 'every hour will gather as much data as can be stored on a dozen PC hard disks'. 'ENVISAT' (ENVIronmental SATellite) has been in the works for almost fourteen years with a price tag of 2.3 billion (Euro)."
how much data the European Space Agency thinks can be stored on a "PC Hard Disk" nowadays... 1 GB, 10 GB, 100 GB? They're a little short on meaningful statistics. But it's a press release - the only time the press does math is when one of them gets stuck with the bar tab and figures out a tip.
It would also be interesting to hear what storage technology they're using. Surely they're not flying a Terabyte RAID5 array (what with launch vibration, etc.). More likely dense and hardened DRAM (and lots of it), I'd guess. It almost makes me want to go read the article to find this out.
Idiots:
The fact that AMERICAN politicians do nothing about SCIENTIFIC DATA from satellites and other sources is a travesty. Global warming DOES exist. I trust the opinions of over 90 Nobel Laureats over at FAS and the over than 150 countries signing the Kyoto protocol (the US being the only country to back out) than your pig-headed "patriotic" asses.
About the population situation:
A bomb is an inadequate metaphor for the population crisis. Basically it boils down to this: recent population expansion is a result of oil, and when the oil runs out (predicted mid-21st century), then the energy wont be there to support the civilization it fostered. Humanity will then regress in what will probably be a messy scramble for resources.
You can see that commercial oil usage and mining began in the mid 19th century, approximately when the population started booming. Oil is the foundation for mechanical and electrical energy necessary for industry, farming, and communication, which creates a positive feedback loop with science and medicine, thus progressing population growth through lower mortality, higher birth rate, and more food.
The special thing about oil is that the payoff in energy is so much higher than the amount you put in to harvest it, unlike most other renewable sources.
A good analogy for our present situation: Imagine humans are extinct through some virus. Somewhere in mid-california there are huge werehouses of packaged food. A small pack of bears, say 50, finds this werehouse and begins to sustain themselves on it. After a few generations, there are 5000 bears. Then the food runs out. What happens to the bears?
We are the bears, and the the food is oil. But we are different. We have brains and can figure out how to lower our energy usage and/or find new sources. But we only have 50 years.
LS
There is a fine line between being a cultivated citizen and being someone else's crop. - A. J. Patrick Liszkie
I assume this data rate is decoded, not the raw telemetry, which is quite useless. Lets see.
The 'housekeeping data' of a satellite contains thousands of satellite parameters, e.g. orbital position, currents, voltages, radiation level, temperatures, what is on/off, status of each instrument. On many scientific satellites, all this affects the performance of all instruments. Often the HK data is recorded once per a few seconds.
This is because when voltage across some critical part is raising, you have to shut the satellite down. Then, from the last set of HK data, you have to fig out what is wrong, and correct or shut down the dangerous part, and still have a 90% functional satellite.
Lets assume you have of the order 10000 parameters to monitor, and the values are recorded 15 times/minute. Assume each values takes five bytes when decoded (including a STRING for parameter name. The raw telemetry will of course be more compact). This gives 10000x15x60x24x5 bytes/day, or about 1 GB/day, just to know the satellite is OK.
Now, add the HK, calibration and science data for each instrument. I have analyzed some data from satellite X-ray instruments, so I use it as a crude estimate. (This is very crude, other instruments may be completely different) A modern X-ray instrument produces about 1GB/hour in decoded data (instrumental HK, calibration, science). Thus,we have about 20 GB/day/instrument. I haven't bothered to read the article, but I assume the satellite contains about half a dozen instruments.
This would produce about 100 GB/day. Problem solved.
Eric Chaisson said it best in the "Hubble Wars". These expensive big science projects are a mistake that shows the ESA did not learn from NASA.
The slowness of deploying these giant boondoggles and the observation that it would have been designed differently is telling.
Ten 200 million euro instruments would have been much better.
I can not understand why so many people continue to be taken in by the global warming/cooling scam. My only supposition is that, faced with the realization that man has essentially no impact on the universe at large, it become vitally important for them to believe that at least they are having a major impact on the earth. The fact that we are still minor players in the biosphere (there are, for example, well over a metric ton of termites per human, and termites are minor players among the insects. The insects, in turn, are dwarfed by the plant kingdom,...) is evidently so scary to them that they simply can't accept it.
-- MarkusQ