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Rare 'Annular Solar Eclipse' Tonight
New submitter Trubacca writes "The Northern-Pacific "Ring of Fire" has an opportunity tonight to observe an entirely different "ring of fire": an annular solar eclipse where the moon, owing to its distance from the Earth, seems smaller than the apparent diameter of the sun. This results in the fiery ring for which the phenomenon takes its name. Space.com has a decent write-up on the path of the eclipse, times, and tips for safe-viewing."
http://www.timeanddate.com/eclipse/solar/2012-may-20 is a nice resource.
This is incorrect. Here is a live feed. Kicks off at 6PM Pacific time.
Help stamp out iliturcy.
You can't view it directly (at least not if you want your eyes to keep working) but you can make a pinhole viewer with minimal supplies and tools.
Lots of options for variation, but I did this: Cut a postage-stamp sized hole in a cereal box (or something suitably opaque). Cut a small square of aluminum foil (scavenged from your tinfoil hat, if necessary) and tape it over the hole. Then use a pin to make the smallest hole possible in the foil.
Hold the cardboard w/ pinhole up orthogonal to the sun, and project the pinhole image onto a white card.
You'll see a tiny (reversed) image of the sun in the form of a small circle, and as the moon occludes it, you'll see it clearly.
A one megaton thermonuclear weapon converts 47 grams of matter into energy. The combined nuclear arsenal of the Earth, 13,000 megatons, would convert 611,000 grams or 611 kg. or 0.611 metric tons of matter into energy. The Sun converts 400 million metric tons of matter into energy each second, thus the expression "gnat's fart in a hurricane" comes to mind.
Annular eclipses occur every 15 months on average.
NASA have a lot of solar eclipse stats for anyone interested.
The transit of venus will be visible from most of North America (assuming no weather issues):
Unfortunately, the NASA eclipse website's taking a hammering today, but this should be the map (try the link tomorrow)
http://eclipse.gsfc.nasa.gov/OH/tran/TOV2012-Fig01.pdf
And there's an official gathering near you, too:
http://venustransit.gsfc.nasa.gov/events/viewapprovedevent/id/212
For the transit times & path from your area, see:
http://transitofvenus.nl/wp/where-when/local-transit-times/
Build it, and they will come^Hplain.
If every country on Earth fired all of their nukes into the sun, what would be the reaction?
The first problem would be finding a way to give all those ballistic nukes the ability to achieve escape velocity...
Then you'd have to deal with the second problem, cancelling each nuke's orbital momentum (around the sun). The people who do the various probes have explained that the most difficult problem was the recent probe that's now orbiting Mercury. Reaching Mercury, or even worse, the sun, requires dumping most of the momentum that your craft inherits from the Earth, and doing that directly takes a huge amount of fuel. The current Mercury orbiter took several years to get there, because they saved fuel by using the orbital "slingshot" approach of making numerous passes past other planets (mostly Earth and Mercury) in such a way that those planets "stole" momentum from the probe. The math for this is a bit tricky, and I'm not about to try posting it here. (But google can find it for you, if you're interested. ;-)
If you want to get rid of all our nukes, a far better approach would be to extract the fissile material and recycle it as power-plant rods. That would also have the benefit of converting part of it into valuable isotopes for medical and scientific uses.
OTOH, if you really wanted to waste it by tossing it into the sun, the sun wouldn't even notice such a trivial amount of added matter. The radioactivity would be trivial compared to what the sun (basically a huge runaway fusion reactor) is producing every second.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
The sun might be big but it does not generate that kind of energy - its energy output is about 100 times smaller than your number at 5 million tons of mass per second converted to energy which it gets from the 700 million tons of hydrogen it fuses into helium every second.