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Not bad really. One out of two correct gives you a better average score than most futurists: Flying bike

Actually, GPS does require a very accurate clock. Several of them, in fact. Luckily, they put them way up in the sky, on satellites. This is how the system works: the GPS satellites are constantly transmitting a signal which contains (among other things) their ID code and the time. The receiver uses these time signals to figure out how far away the satellites are, and from there discover its position. (This is a gross oversimplification, but you get the idea.) An atomic clock is NOT required in the receiver, or on the ground at all.

For a less gross oversimplification: :-)
http://www.nasm.si.edu/exhibitions/gps/work.html

None of us would be here today if some big beureaucratic government kept the boat in the dock until the sailors fixed every little flaw in the boat.

Some of us would be.

For what it's worth, the temperature at 65kft, according to the 1976 Standard Atmosphere, is -70 F (the 4-degree per 1 kft doesn't hold all the way up because there is a temperature inversion between 10 kft and 45 kft).

I'm not sure about the upper limit on 200 kts for the winds aloft, but you should state the winds can be from -200 kts to +200 kts because it makes a big difference for an airplane whether it is going into a headwind or not.

The aerodynamic force goes as the density times the square of the velocity. At 65kft the density drops from 1.225 kg/m3 to 0.0907 kg/m3, so all other things equal (namely the area of the wing), to maintain the same lift you need to increase your relative velocity about four times, so your 60 kts becomes 240 kts. As an example, the SR-71 has a takeoff speed of 334 kph, so to fly at 85kft (density 0.0342 kg/m3) it needs to fly at least 2000 kph just to stay aloft (and in fact the link I provided says it can go over 3500 kph!).

Actually, I have seen a very similar thing recently at National Design Museum's exhibition called "extreme textile".
http://ndm.si.edu/extexsitelet/index.htm
In the "Smarter" section, they had a Nike's vest which is capable to communicate remotely. They also shown some militaly clothes which work as satelite antenna.
The idea of monitering bio thing is also implemented in astronauts' suits already, although they are not small enough right now...

Cutler's Design Workbook for NT/OS2 made it into the Smithsonian.

http://www.nasm.si.edu/research/dsh/artifacts/HS-E nterprise.htm
Yes, I had used the preview button with parent, I just didn't READ it carefully.

There's no evidence of biological change. The evidence is that the change is not biological. The evidence is that the changes, instead of being biological, is due to changes in nutrition and culture.

There's no difference in bone structure, brain size in the last 130,000 years. There's very little difference in brain size between modern humans and Homo Erectus (some Homo Erectus skulls are a normal size for a man), which goes back over 1 million years.

We are indeed quite different that we were 10000 years ago, but biological evolution is much slower than that, amd the difference are caused by other factors.

Quick summary.

More accuracy and detail.

Last time I checked, my vodka was not bubbly.

The Air and Space Museum has the shuttle, Enterprise, on display but alas you can't get anything other than a frontal view from about 10-20 yards away.

I was there on opening day and the whole museum is pretty impressive in terms of old aircraft. SR-71, Enola Gay, a Concorde, and oodles more aircraft. All fully assembled (save the shuttle since the wings came off to test after the Columbia disaster).

Remember the Maine!

History doesn't repeat itself, but it sure does rhyme.

--Mike--

Feed-forward from the input just creates instability. Early rocket pioneers found that out, which is why Goddard had an engine at the top, and von Braun had to develop complex gyro control systems.

I'm getting a little off-topic, but I think this is actually incorrect, though I don't understand why. From this page:

Goddard and Sachs loaded the rocket while Sachs lighted the torch and ignited the pyrotechnic igniter. Goddard controlled the valves. At first, when the combustion was started, the rocket would not rise because the thrust was lower than the weight of the rocket. Then, when it exceeded the weight and reached an estimated 18 lbs, the rocket first climbed a few inches then shot up but but was not that stable. (In addition to proving that liquid fuel rockets can fly, Goddard also realized that his "nose-drive" design was inherently unstable and in his rockets the motor was placed at the base of the rocket.)

You should credit your sources when posting someone else's material. Wouldn't want to be accused of plagerism, after all.

At the time that they landed, they thought they had enough fuel to fly most of the way across the US. I was watching the live coverage, and I remember it. It wasn't until after they drained/dipped the tanks that they realized they were running so short on fuel.

A few gallons would probably have been all that they needed to do this. At that point the thing was mostly a glider.

The Voyager flew most of the time only on the Continental IOL-200 rear engine. It's an unusual engine, so fuel flow specs aren't easily found, but the Continental O-200 from which it was derived consumes 5.5-6 gallons/hour (or 33-36 lbs/hour) at cruise. The IOL-200 is more efficient, but not enough to make a substantial difference in endurance with only 6 of fuel. That's usually over the range of 50% to 75% power, which is what aviation engines cruise at. Outside that range, they are not very efficient.

You can get some idea of Voyager's average fuel flow from:

http://www.nasm.si.edu/research/aero/aircraft/ruta nvoy.htm

They lifted off with 7,011 lbs of fuel. They landed with 48 lbs (8 gallons). Having flown 24,986 miles in just a bit over 216 hours, that's 3.6 miles per lb of fuel, or 32 lb/hour. Using those average numbers, they weren't going to get much further on 48 lbs of fuel.

Of course as you point out, they had burned off most of their gross weight. But the reduced weight would only reduce the induced drag. It wouldn't have reduced the parasitic drag. So, the increased fuel efficiency would not be as large as the difference in the gross weight. There's no way they could have kept the engine running for 3000+ miles on 8 gallons of gas.

And I can tell you from personal experience (I have a glider rating on my pilot certificate), even the highest performance glider won't cover any significant portion of the distance across the continental US in the absence of power or lift in the form of thermals or mountain waves. And the Voyager wasn't designed to fly any distance without power.

The sued the govt and maybe the story that all the companies from WWI _voluntarily_ pooled their resources, is just that - a nice story.

The US govt took Pitcairn helicopter related patents and gave them to various Defense Contractors, I believe the Pitcairn lawsuit was successful but there may be a gag order, not sure.

Pitcairn references:
The US Govt "bought" their airfield: http://www.cnrma.navy.mil/nasjrbwg/history.htm
Autogiro Company of America v. The United States: National Air and Space Museum 10.9 ft^3 of stuff...
Early aviation pioneer: http://www.phillyburbs.com/pb-dyn/news/113-0101200 5-425395.html

They did? Funny, I (and most anyone else with a bit of computer history knowledge) always thought it was Ed Roberts.

Curta Mechanical Calculator
Moon Watch
IBM Model M Keyboard
K&E Decilon Slide Rule
HP-41 Programmable Calculator
Varian A-60 NMR
Electron Microscope

The life and times of AT&T is an integral part of 20th century US history. If SBC is stupid enough to send that history to the garbage pile, then SBC must be destroyed as well because they would have done a great disservice to posterity.

Mission statement from the SI website:

Secretary Small's Vision

"The Smithsonian is committed to enlarging our shared understanding of the mosaic that is our national identity by providing authoritative experiences that connect us to our history and our heritage as Americans and to promoting innovation, research and discovery in science. These commitments have been central to the Smithsonian since its founding more than 155 years ago."

Lawrence M. Small, Secretary of the Smithsonian

If you are ever in the Washington DC area, try to visit the Smithsonian Instution if you can. Know that you can spend an entire day in just one or two buildings devoted to just a few subjects.

The National Air and Space Museum is the most popular of all the Smithsonian buildings. Plan on a full day there. If you can't make it downtown but fly into Washington Dulles, the Udvar-Hazy Annex of the A&S is on Dulles' property. Plan on at least 4 hours there if you want see most of it.

Okay, getting a little OT there. So sue me.

barcoding.si.edu
From their DNA barcode page:
DNA barcode sequences are very short relative to the entire genome and they can be obtained reasonably quickly and cheaply. The cytochrome c oxidase subunit 1 mitochondrial region (COI) is emerging as the standard barcode region for higher animals. It is 648 nucleotide base pairs long in most groups...

Let us note however that most of our planet's biodiversity is contained in the 60% of the biomass that people don't talk much about: Bacteria. Most of them live in the soil and are difficult to study and are simply unknown. It would seem that this barcoding project does not include Prokaryota ( = Bacteria,Archaea) unfortunately.

Apollo Cameras

The astronaut would stand in one spot, take a picture, turn a little, take another, and so on for a full 360 degrees.

Some Claim we got nothing from the apollo program. For them I direct your attention to theTop 10 Apollo scientific discoveries

The Smithsonian already has a Hubble Test Vehicle. It might be nice to have the real thing but, as you pointed out, from a cost perspective it's totally impractical. Most of the National Air and Space Museum's space hardware (except for Mercury, Gemini and Apollo capsules) are replicas or test articles because there's no way (or no economical way) to get satellites and interplanetary probes back for exhibition.

The only thing Pac Man taught me was that I couldn't cut corners.

...and that you could actually spend quality time "munching pills while listening to repetitive music." Amazing what they put in the Smithsonian's collections.

The only thing Pac Man taught me was that I couldn't cut corners.

...and that you could actually spend quality time "munching pills while listening to repetitive music." Amazing what they put in the Smithsonian's collections.

In that case, I seriously hope space shuttle rescues are/become as simple as a module jettison. It seemed like extreme luck there.

Dichotomy...forgive me, I'm a sucker for good English.

The asteroid which caused the "dinosaur extinction" 65 million years ago was only 10 km (6 miles) wide.

I remember that! I was too old for them, but I had a Little Professor that eventually wore out and had to be chucked. He taught me all the math skills that I didn't want to know. To bad it didn't stick, or maybe it did, but writing on the board just wasn't as much fun as the old LEDs.

Which time? The 1903 Flyer seems to fit his definition.

You foolish Americans believe everything they teach you in your facist schools. Learn to think for youself! Don't believe propaganda such as this Americans have given nothing to the world but war! You really think Edison invented the light bulb! Hah, some Candian though of it before him! Sure, it never worked until Edison touched it, but he DID NOT INVENT IT!. AMERICA CREATED NOTHING except BRITNEY SPEARS AND SLUTTISM.

The only thing you ever invented was the nuke! That shows what war mongers you are! We all know that George W. Bush has not captured Osama bin Laden so that the Christian Coalition, the Jews, big corporations, white men, and Republicans could oppress liberals.

You can't hide the truth!

1 down, 1 to go.

However, the price tag of the robotic mission is between $1 billion and $2 billion, almost the cost of a new space telescope.

Heck, you could shave a few hundred thousand off that pricetag if you built a new HST around the "backup" primary mirror made by Kodak (which was figured and tested correctly). NASA would just have to get it from The National Air and Space Museum.

for those who where not around here's some links to the AGC, DSKY and more:
*Apollo Guidance Computer (AGC)

*slash article with source code listing

*Simulation of Apollo Guidance Computer

*DSKY

Your first calculator worked in Reverse Polish? Your father must have really loved you.

My first calculator, the Texas Instruments Little Professor, was not quite so advanced. Also, it was considerably more bulky than your Sinclair Scientific. However, it was a gift from a cherished engineer-type uncle, and I was quite attached. Unlike your calculator, it preferred to ask questions than provide answers (this makes it similar to some professors I know). Mostly, it asked about the times tables, which I became quite proficient at as a child.

My only complaint is that to this day the professor only comes in a male version.

A much bigger deal was the retirement, last August, of the Dash-80. The Dash-80, the original KC-135/Boeing 707 prototype, first flew in 1954. It was used for many test programs therafter, flying until 2003. This was the prototype of the first really successful jetliner.

(The DeHavilland Comet flew years before the Dash-80, but the underpowered Comet had metal fatigue problems and all were grounded after several crashes. The Tupolev Tu-104 was a civilian version of the Badger bomber, braking chutes and all. The Dash-80/707/KC-135 was the first commercial transport that really worked.)

The Salon article has a tangential mention and link to an article about Orthodox Jews filtering NYC water because, while being "some of the purest municipal water in the world," it is contaminated with copepods, which are tiny crustaceans, and thus not kosher. What shocked me about this is that copepods are very large when it comes to filtration...for .2mm up to 10mm, with most around a milimeter according to this and some species are human parasites! (though almost certainly not the species found in NYC tap water, I'm presuming). And yet the article on NYC claims the NYC Department of Environmental Protection claims they are "impossible to do away."

Now, what surprises me is that a contaminant this large is a problem to do away with. What does that say about the ability of NYC water treatment to filter out far tinier contaminants like bacteria and protists? Are the copepods infiltritating the system post-treatment? Clearly, if NYC has some of the purest municipal water in the world, there's something missing from the story here. I'm sure there's some hydrologist or inverterbrate zoologist reading Slashdot that could shed more light on what's going on,

It does happen, and from natural causes, too.

(this has already happened in Africa, I believe)

Yes they did, lakes with CO2 saturated water at the bottom that release it suddenly asphyxiating thousands in the area. link here. Pretty bizarre event.

It's amusing, but in 1967 this Fluidic Amplifier was billed as "the simplest device known for setting up digital circuit applications."

1908 German Pigeon Fleet... As a remote sensing experiment - I believe they got 1 picture of a castle and a lot they couldn't use...

Boy, what I would give to be able to sit in that seat and flip those switches!

I doubt that they'll let you sit in it, but you can see the American space shuttle Enterprise for yourself at the McDonnell Space Hangar facility of the Smithsonian Institute's National Air and Space Museum. It's out near Dulles International Airport in northern Virginia.

Enterprise was parked out at Dulles for a while, and it too seemed to be abandoned, but in retrospect it seems likely that it was just waiting during the construction of its new home.

Boy, what I would give to be able to sit in that seat and flip those switches!

I doubt that they'll let you sit in it, but you can see the American space shuttle Enterprise for yourself at the McDonnell Space Hangar facility of the Smithsonian Institute's National Air and Space Museum. It's out near Dulles International Airport in northern Virginia.

Enterprise was parked out at Dulles for a while, and it too seemed to be abandoned, but in retrospect it seems likely that it was just waiting during the construction of its new home.

The airplane was actually developed for civilian uses first, and only became a military technology after entrepreneurs worked out the fundimental problems of control surfaces, navigation, range, and cargo capacity.

Actually the first military airplane predates the commercial transport flight. Commercial flight didn't become economically viable until well after WWI.

The airplane was actually developed for civilian uses first, and only became a military technology after entrepreneurs worked out the fundimental problems of control surfaces, navigation, range, and cargo capacity.

Actually the first military airplane predates the commercial transport flight. Commercial flight didn't become economically viable until well after WWI.

Robert E. Fulton, a man who as a teenager was the first to ride around the globe on a motorcycle, already invented the flying car in 1945. He called it the Airphibian. In 1950 he flew it to Washington D.C. where he landed and then drove it to the Civil Aeronautics Association where it was certified for use. It traveled 110 mph in the air and 55 mph on the ground, and changed between car and plane in five minutes due to its simple system for removing the wings and propeller. Charles Lindhberg flew it and declared it "an improvement." It never did well commercially and sold only under 600 total. There is only one remaining today. It is in the Smithsonian. More Info: http://www.nasm.si.edu/research/aero/aircraft/fult on.htm
History: http://travel.howstuffworks.com/flying-car1.htm

Robert E. Fulton, a man who as a teenager was the first to ride around the globe on a motorcycle, already invented the flying car in 1945. He called it the Airphibian. In 1950 he flew it to Washington D.C. where he landed and then drove it to the Civil Aeronautics Association where it was certified for use. It traveled 110 mph in the air and 55 mph on the ground, and changed between car and plane in five minutes due to its simple system for removing the wings and propeller. Charles Lindhberg flew it and declared it "an improvement." It never did well commercially and sold only under 600 total. There is only one remaining today. It is in the Smithsonian. More Info: http://www.nasm.si.edu/research/aero/aircraft/fult on.htm
History: http://travel.howstuffworks.com/flying-car1.htm

This land is your land, this land is my land
From the redwood forest to the New York island.
From the snow-capped mountains to the Gulf Stream waters
This land is made for you and me.

As I go walkin' my ribbon of highway
I see all around me my blue blue skyway
Everywhere around me the wind keeps a-whistlin'
This land is made for you and me.

I'm a-chasin' my shadow out across this roadmap
To my wheat fields waving, to my cornfield dancing
As I go walkin' this wind keeps talkin'
This land is made for you and me.

I can see your mailbox, I can see your doorstep
I can feel my wind rock your tip-top treetop
All around your house there my sunbeam whispers
This land is made for you and me.

"Was a big high wall there that tried to stop me
A sign was painted, said 'Private property.'
But on the other side it didn't say nothing.
This land was made for you and me."

• At an NPR story: here and here
• Here for more info.
• Here for info from the Woodiy Guthrie foundation.
• Here for the Lyrics from Arlo Guthrie, Woody's Son.
• 
  
  IMHO whoever claims to "own" this is as sick as the people who claim to "own" the image of Martin Luther King as property. See the commentrary at the internet archive: here.

Yeah, hominid fossils are pretty thin on the ground.
Partly that's because Africa is a difficult and dangerous place to conduct archeological digs. We have a much better sense for the history of the European Neanderthals, for example just because Europe is an easy place to work.

Homo Erectus is fairly well represented, but as you get deeper in time, the fossil record gets spottier. We've only found a handful of Australopithecus, for example.
But we know that they were there. At Laetoli in Tanzania, there's that famous set of footprints captured in volcanic ash:
Laetoli Footprints
And that was about 3.6 Million years ago. Pretty deep history.

But I'm curious what you're getting at? Do you support the multi-regional hypothesis? Humans evolved independently from scattered Homo Erectus populations in locations other than Africa?

Or that we evolved in East Africa, not South Africa (which is, I understand a point of contention)

Or are you simply arguing for divine creation in the relatively recent past?

So does any of this surprise us?
No but it should disgust us. US$793M for rights to broadcast seems a bit rediculous.

However this has been the way it has always been. There is a nice artical in Smithsonian this month about how the ancient Greeks actually did it and there was pleanty of bribery, profits, and raking in the dough back then too.

I assume that the hypothetical object in near-sun orbit does not have much more surface on the side that shows away from the sun that on the side that faces the sun. (For a long cylindrical object this would not hold, but I assumed that we were talking about a somehow "football-field" shaped object that is flat rather than long.)

Ah, I think I see what you're saying. Basically if the surface area of the cooling section is equivalent to the surface area of the warming section, then there will be some difficulty in exhausting the heat fast enough to keep the cold side significantly colder than the warm side. Correct?

I did some research on this to find how NASA does it with the RTGs. It seems they extend vanes off the surface of the RTG to provide enough cooling (image). Conceivably, something similar could be done with the cooling cylinder of the engine(s). Instead of having a solid wall facing the rear, a cylinder with vanes could extend from the back of the station.

As long as we can provide enough cooling area to keep the cylinder(s) cool, we should have a very efficient engine. Even if we allow the rear area to reach 450K, that still gives our engine an efficiency rating of 50% ( (900-450)/900x100) = 50%); which is about 30% more efficient than the more fragile Solar Panels.

Thankfully, 900K isn't hard to deal with materials wise. Iron has a melting point of about 1800 Kelvin, which is quite good for the amount of thermal conductivity you're getting.

Now if you *really* want to go the mirrored route, we could build out station out of Tungsten (expensive!). With a melting point of 3700 Kelvin and more than twice the thermal conductivity, we can make the station far hotter than we could otherwise.