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NASA Gravity Probe Launched
ping pong writes "Forty-five years in the making and 24 hours late, NASA launched the $700 million satellite into orbit today to test Albert Einstein's general theory of relativity. The satellite, which was inserted into a polar orbit, will spend two months getting ready, then 16 months making measurements." NASA's mission news has more.
could this post be considered a relatively first post?
We fail to understand the gravity of this situation.
Yeah, I guess I'm funny like that.
The experiment uses three key components: a spinning sphere, a telescope and a star.
One of these components can't be had from Sharper Image : can you guess which?
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
The greatest men are those who keep shaking up the world even after they are long gone. Albert Einstein wasn't a businessman, or a soldier, but look how much research and spending has been affected by his findings. Kudos!
The most facinating tidbit from the NASA article is the absoutely beyond perfect Niobium-coated Quartz spheres at the heart of the ultra-precise gyroscopes.
A quick Google found this link with more cool details, including:
* The 1.5-inch diameter rotors are within 40 atomic layers (0.3 millionths of an inch) of a perfect sphere.
* "Electrical sphericity" must be held to parts in ten million.
* Each rotor spins inside a quartz housing with clearances to the rotor of barely one thousandth of an inch.
* To lift the rotor on earth takes 1,000V. In space, only a fraction of a volt is needed.
* In 1,000 years the gyroscope should barely lose 1% of its starting speed.
* To isolate the gyroscope from the Earth's magnetic field, it will be shrouded in four layers of lead balloons, plus an outer shield of iron.
Plus these cool facts (and a ton more), there are steampunk-styled drawings of the manufacturing process.
Seems like NASA could make some money selling the rejects (you know there are plenty) as the ultimate shooters!
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
"E had just better equal MC squared...E had just better equal MC squared..."
Wouldn't our understanding of something as fundamental as general relativity far out weigh any kind of understanding we could gain from Mars? Even if life is found on Mars, it does little to solidify our understanding of the fundamental forces of the universe.
Gravity is one of the most important, and least understood forces in the physical world. Mars is just a big rock in orbit around our tiny little sun. Going there is a cooler project that this, but the information garnered from such a mission seems to be less important than what this mission is set to show.
> will spend two months getting ready
Sounds like my girlfriend.
Norman Cook's Ode to Sl
although it seems like a lot of money to spend just for testing his theory
I think it's really a cheap experiment, considering the importance of the results. If there's something wrong or incomplete in Einstein's theory, we (as in humanity) should know about it, firstly because it's the human nature to try to know more all the time, and secondly because it could be very important in practical terms: you wouldn't want to take a plunge off a cliff with your SUV because your GPS receiver had a slight error, would you?
This is theorical science and experimentation at its best. The price is really cheap to advance mankind's knowledge. Compare this to the weekly cost of certain recent military activities that probably won't bring back much to mankind anytime soon...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Gravity is a force that effects everything in our universe (and in theory some other universes :P )
:)
It's a force we can calculate for and predict but we still aren't completely sure HOW it works. So whether this mission proves or disproves Einstein's theories we should at least get data that will help bring us a step closer to understanding a significant force in the universe.
I'm really exicited to see the results in 2 years
The James Webb Space telescope, when launched, will be temperature controlled by simply putting a shield around it on the sun-side, keeping the telescope side cool and out of sunlight.
A pretty simple idea; as once it cools down to equilibrium temperature, there'll be nothing to heat it up.
I really don't think the financial analysis is the correct one. I'm fairly sure the US will derive enough benefit to justify the cost, although the benefit is admitedly difficult to quantify and is amortized over the rest of our specie's existence. Does it matter if the rest of the world gets a free ride? They do pure science too, and we benefit. Science is a collaborative effort. This isn't some billion dollar defense department project seeking a military advantage over a perceived adversary. This is about scientific discovery and learning things that have never been known. In my cynicism concerning politics, I sometimes forget to be optimistic about the science.
>> My ultraviolent Linux switch video.
Wouldn't our understanding of something as fundamental as general relativity far out weigh any kind of understanding we could gain from Mars? Not necessarily. More has been learned from putting this experiment together than will be learned from its results - it is a fine-scale test of one of the most successful theories of all time. Going to Mars, though expensive and such, could be a big deal if only as a proof of concept. Look at how much was learned going to the Moon. Going to Mars is orders of magnitude more complex - interplanetary radiation, the technological and social advances that will let a crew live together for months, getting people there and back ... if we can get to Mars and back we can go anywhere in our Solar System with trivial amounts of scaling.
And, if we do find life on Mars (or elsewhere), that is potentially the most important discovery, um, ever. It tells us things about the fundamental nature of the universe too - and, short of an experiment either detecting gravity waves or detecting an overall curvature to spacetime, there isn't that much experiments will tell us about gravity right at the moment.