The threat communicated did not arise from trilby-flinging basement dwellers hiding behind Guy Fawkes masks. The threat was issued by the information warfare arm of the North Korean Army. The Norks have a number of sleepers around the US and they are feared by the residents of the ethnic Korean neighborhoods and recognized as a threat the .gov. These guys are the real deal. Singer's dismissal of the issue is glib.

The "40% heavier" actually refers to atomic weight, not density. By density, Tungsten is ~70% heaver than lead, Depleted Uranium about 68%. Tungsten's atomic wight is actually ~10% lighter than Lead's. Bulk density is about arrangement of the electrons and the resulting packing of atoms in the solid.

This is Slashdot. You never click on the article.

Get me the amnesia ray!

Hydrogen in a metal matrix. In the 80s it was called cold fusion. Progress in CF has been slow due to a pervasive and comprehensive conspiracy to suppress positive results in the field Funny, they're still at the F&P stage twenty+ years later... Whatever. Good luck with that.

I have a 22 y.o. YNA (big green thing, 50% evil) who is very lazy. He would love to go motoring around the house in one of these things.

I should not google things before i drink my coffee... I completely messed up my delta-v estimate. You are all right, mercury is a difficult target. It would still be worth it... maybe a solar sail or electrostatic decelerator for free delta-V?

I did a cursory goog, and got the impression that the delta-V to Mercury is 1/6th of the delta-V to Mars. Mercury is down the hill from us, not uphill. Mercury would seem to have the added benefit of having 10x the initial solar radiation available for running a sail. I'm a little disappointed to see this topic get so few posts. Mercury has a lot to offer from an explorational perspective. Plentiful energy, a B-field, easy to get to.... much more interesting than Mars in many ways.

You have it exactly backwards. The LHC has 8 times more energy and smashes significantly more protons. The LHC has gotten nearly as much data in two years as the Tevatron collider got in its ~15 year lifetime.

Luckily, the physicist has since discovered another clever experiment which the aliens can use to differentiate between what we call matter and antimatter. There's a certain type of particle that can transform into it's antiparticle and back again. But the catch is that one of the transformations will happen more often than the other. That means that even if the alien swaps matter for antimatter they will still be able to tell which is which by looking at which transformation dominates. (More details here)

"Now," the physicist admits "this all assumes that the aliens haven't swapped the direction of time on us as well! Buggers might just have effects preceding causes." (See CPT symmetry)

Sending neutrino messages is old hat. Receiving them is a bit more difficult, because neutrinos are so damned difficult to detect. They basically don't interact with anything, which is why Fermilab can shoot a neutrino beam an a 735 km underground trip to Minnesota. So to receive your IM, you need a detector the mass of the USS Iowa. I sent out "Dinner is served" back in the 80s, by the way.

They just can't part with the Tevatron . . . this recycling line is just an excuse to keep it around.

Assuming you would want to, it is non-trivial to just dispose of 4 miles of superconducting magnets.

Anyways, the part of the Tevatron that you are most likely to find reuse is the 4 miles of tunnel. The civil construction to dig a tunnel that big, complete with tunnel penetrations and service buildings is a significant portion of the cost of any project. You would be a fool to just fill in such a valuable commodity just because you don't have a use of it today.

And that's ignoring all the parts that are already being scrounged for use in the NoVA upgrades. So no, keeping it around is not merely a case of geek sentiment.

They even have an online store.

I thought gps was a military thing and that all that civvy stuff was just freeloading.

I remember, as an ardent newcomer to L5, talking about exactly this sort of thing with Eric Drexler in a park somewhere in the Bay Area, back in 1983. What the heck, good luck to the Chinese. Maybe they'll even do it. (although the delta-V required is truly staggering, even for the kind of intercept described)