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Generally, most of the data volume seems to come from reading out large CCDs. For example, a friend here at Caltech is doing fluid dynamics research in which they read out a 1024x1024 array at 1000 fps for a couple of seconds (I think the pixels are 12 bits each or so). This isn't too different from the interferometers, which are creating data at sustained rates of around 5-10 KHz. At those volumes, it doesn't take long to fill a terabyte, and when you go to long-term storage, you're into petabytes. Of course, for time-series image data like this, lossless differential compression schemes can be a big help (by a factor of four or ten), enough to save a few million dollars of storage space.

Generally, most of the data volume seems to come from reading out large CCDs. For example, a friend here at Caltech is doing fluid dynamics research in which they read out a 1024x1024 array at 1000 fps for a couple of seconds (I think the pixels are 12 bits each or so). This isn't too different from the interferometers, which are creating data at sustained rates of around 5-10 KHz. At those volumes, it doesn't take long to fill a terabyte, and when you go to long-term storage, you're into petabytes. Of course, for time-series image data like this, lossless differential compression schemes can be a big help (by a factor of four or ten), enough to save a few million dollars of storage space.

The Terrestrial Planet Finder is a NASA mission slated for the 2009-2012 launch range which will interferometrically detect terrestrial-massed planets... the mission has a preliminary web page here. Even more excited, the mission beyond TPF, called the Planet Imager right now, would actually put a 50x50 pixel spread image on the planet...

And I do so love using the word "interferometrically"...

I bought this book about a year ago and was very disappointed. It's mostly old Datamation and other mainstream computer trade magazine articles wrapped with meandering introductions. There are some interesting details here but basically I was unimpressed with the quality. The projects covered are mostly glass house apps and the revelance is mostly how we have moved beyond that mode.

It's too bad that Glass provided virtually no countering examples of projects that have fared well under better software engineering and management discipline. Yes, many large projects are "runaways" (more than twice over budget or time). Yes, there is *something* you can do about it.

For example, in the mega-project range, look at some of the work being done by the Automated Software Engineering group at NASA Ames. Successes in the open source field like Linux, Perl, Samba and many others demonstrate how alternative methods to software development can produce results. If you want rigorous analysis of software development, check the work of Watts Humphreys, Capers Jones, and the Software Engineering Institute at Carnegie-Mellon, developers the Capability Maturity Model, which if not exactly a template for software development in large organizations at least provides a model to aspire to.

So I guess my disappointment with this book is that it was such a slapdash, backward-looking view on a very important subject.

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I remember reading somewhere that zero state energy is by far the most powerful and portable, but like matter/antimatter, you just have to find out:

a) How do we get the stuff, and;
b) How do we harness the energy.

With Zero state energy, there is enough (theoretically) in one cubic centimetre (thats about a 1/16 of a cubic inch for you Americans living in the non-decimal world) to boil the worlds oceans.

Now that's powerful stuff!

That one did get my attention. So besides the known big bad nasties out there, there are a lot more bigger, badder, nastier ones we have no clue about...

fun thought ;)

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Also, the TIFF 6 spec can be found on this site:
http://www-mipl.jpl.nasa.gov/~ndr/tiff/h tml/

Quote of the week, IMHO. It's a few paragraphs down the page.

Triana is a joke.
Having another Sun-synchronous satellite would be sweet, but not just for pretty pictures.
For the cost of a webmaster, this site has done exactly what Triana is supposed to do, but does it today. Warning, requires some real bandwidth:
http://farside.gsfc.nasa.gov/ISTO/dro/global/page1 .html

• Launch costs drop radically (yeah Roton!)
• It becomes profitably in some way.

Very few satellites "move on their own" (outside of their normal orbital motion), due to limited fuel on board. Once in orbit, they pretty much stay in the same orbits they start in.

And, there are published orbits for nearly every satellite, not just the geosynchronous ones. Take a look here and click on the OIG Main Page link at the bottom of the page.

Yes, it's reasonable to expect that secret satellites would not have their orbits published, certainly by the launching government and those friendly to them. However, there are other governments capable of figuring out the orbits and publishing them.

Actually, X ray diffraction studies show that the bond lengths are all identical, so it's really more like each is a 1.666-order bond. This phenomenon, called resonance, also appears in benzene. It is thought to be a quantum superposition of all the possible different ways of arranging the double bonds. (What we call a double bond is actually a superposition of a sigma orbital and a pi orbital.)

The pi orbitals in a sheet of graphite or buckytube all blend together, and depending on the tube's chirality (how the hexagons are oriented relative to the cylindrical axis), this can either allow electrons to move up and down the tube very easily, or it can give semiconductor-like behavior. So a trick to building these kinds of circuits is to find joints that will allow you to join tubes of differing chirality.

Fullerenes are generally quite stable molecules, so it's not too surprising that they describe difficulty in getting current into and out of the buckytube. It turns out that it's not too hard to stick little molecular pieces onto the sides of buckytubes. Al Globus at NASA has done a lot of thinking and simulations relating to applications of nanotubes, including adding teeth to make them function as gears.

Possibly the best source of information on fullerenes is Richard Smalley's Center for Nanoscale Science and Technology at Rice University. Smalley received a Nobel prize for the discovery of fullerenes. The CNST has an interesting-looking PDF document describing the Carbon Nanotechnology Laboratory, and discussing the science of fullerenes and some of the potential applications. Fun stuff.

Actually, X ray diffraction studies show that the bond lengths are all identical, so it's really more like each is a 1.666-order bond. This phenomenon, called resonance, also appears in benzene. It is thought to be a quantum superposition of all the possible different ways of arranging the double bonds. (What we call a double bond is actually a superposition of a sigma orbital and a pi orbital.)

The pi orbitals in a sheet of graphite or buckytube all blend together, and depending on the tube's chirality (how the hexagons are oriented relative to the cylindrical axis), this can either allow electrons to move up and down the tube very easily, or it can give semiconductor-like behavior. So a trick to building these kinds of circuits is to find joints that will allow you to join tubes of differing chirality.

Fullerenes are generally quite stable molecules, so it's not too surprising that they describe difficulty in getting current into and out of the buckytube. It turns out that it's not too hard to stick little molecular pieces onto the sides of buckytubes. Al Globus at NASA has done a lot of thinking and simulations relating to applications of nanotubes, including adding teeth to make them function as gears.

Possibly the best source of information on fullerenes is Richard Smalley's Center for Nanoscale Science and Technology at Rice University. Smalley received a Nobel prize for the discovery of fullerenes. The CNST has an interesting-looking PDF document describing the Carbon Nanotechnology Laboratory, and discussing the science of fullerenes and some of the potential applications. Fun stuff.