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NASA May Send Landers To Europa In 2020
wisebabo writes "So here's a proposal by NASA to send landers to Europa to look for life. They are sending two landers because of the risks in landing on Europa. They got that right! First is the 500 million mile distance from the Sun, which will probably necessitate RTGs (Juno uses solar panels, but they are huge) and will cause at least an hour of lag time for communications. Then there is the intense gravitational field of Jupiter, which will require a lot of fuel to get into Jovian and then Europan orbit. (It's equivalent to traveling amongst the inner planets!) The radiation in space around Jupiter is tremendous, so the spacecraft may need to be 'armored' like Juno. Landing on Europa is going to be crazy; there aren't any hi-res maps of the landing areas (unlike Mars) and even if there were, the geography of Europa might change due to the shifting ice. Since there is no atmosphere, it'll be rockets down all the way; very expensive in terms of fuel — like landing on the Moon. Finally, who knows what the surface is like; is it a powder, rock hard, crumbly or slippery? In a couple respects, looking for life on Titan (where we've already landed one simple probe) would be a lot easier: dense atmosphere, no radiation, radar mapped from space, knowledge of surface). If only we could do both!"
Have we forgotten? "All these worlds are yours, except Europa. Attempt no landing there." (Stupid NO-CAPS slashdot filter...)
HSJ$$*&#^!#+++ATH0
NO CARRIER
This does not sound like a right schedule - as the Jupiter Europa Orbiter mission was put on hold recently. Having worked a bit on it, the expected level of radiation was very high, even when compared to Juno. It follows on a long tradition of missions to Europe being cancelled (see the Jupiter Icy Moon Orbiter which was cancelled in 2005). Fans of Arthur C. Clarke will see a trend there. The Laplace mission (from ESA) which is aiming for Ganymede is currently trying to pick on bits of JEO science targets by adding flybys of Europe to the original mission plan - we will see how far it goes.
"All these worlds Are yours except Europa Attempt no Landing there"
Yep, that part is from the book 2010 by Arthur C Clarke
The rest is from a crappy movie based on the book
You have to remember that there's no friction in space. Going down a gravity well is easy, but stopping at the bottom requires energy. It's like a roller coaster heading down from a peak, with Jupiter at the bottom. As you approach Jupiter, it's gravity will speed you up (relative to Jupiter). Unless you put in energy to counteract that extra speed, you shoot past and fly right up the other side of the gravity well (up the next peak).
That said, the summary is wrong. Jupiter has lots of moons. You can do the opposite of a gravitational slingshot. Approach the moon from the forward direction, and thereby transfer some of your kinetic energy to the moon. Do it enough times and you're in Jupiter's orbit. That's pretty much how Galileo and Cassini were inserted into orbits around Jupiter and Saturn. You only need fuel or aerobraking to enter into orbit around planets without large moons, like Mars.
What wavelength radio waves penetrate underwater?
Well, basically none. Radio waves can travel some distance underwater but are quickly damped. For submarines very low frequencies of a few Hz have been used. They can get a bit deeper, but you need very, very large antenna's for that.
"It's too bad that stupidity isn't painful." - Anton LaVey
A group of congress people killed it , on purpose, by making it pay-forward its pension fund for 75 years. Almost no company could survive that.
Is that what any of the news reports say? No. Most of them say "oh, email killed it". complete horse shit. if they hadn't had to pre-fund their pension, they would have been rather profitable in recent years. Unlike, say, Goldman Sachs, Fannie Mae, Merrill Lynch, Wachovia, General Motors, Chrysler, and every other bailed out shit hole full of ivy league douchebags and hedge fund assholes.
That's pure spin. Changing the USPS to account for 75 years worth of liabilities brings it in line with the private sector. It used to be under normal government accounting rules, which are a lot more "flexible." If anybody in the private sector tries the accounting tricks the government lets itself get away with, they find themselves on the sharp end of an audit pretty damn quick.
In the private sector, federal law requires you to fully fund a pension plan, including all future liabilities. That's stricter than the USPS's 75 year requirement. In practice they're pretty similar, because you're not likely to have any significant liabilities beyond 75 years.
I don't have working knowledge of US military hardware internals, and if I did I certainly couldn't comment about it, but I imagine to some extent you're correct. Though there's still a big difference of knowledge and skill between base parts and a final design. For instance, getting photos and material samples from a downed US stealth fighter or helicopter doesn't mean the Chinese can go right out and build one of their own, or automatically absorb the theory and science behind it. But they are improving much more rapidly than the US military thought possible; case in point, the Chinese sub which surfaced within torpedo range of a US carrier without being detected.
But yes, the US has certainly been sold down the river by politicians and corporations who were willing to put personal desires for wealth and power above the good of the country. The lack of a large high-tech manufacturing base in America is certainly, as you point out, as much a national security issue as it is an economic one.