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Comment Re:How could the Earth heat it? (Score 1) 93

I was being a smartass, but if you insist... your comment is incorrect throughout. The paper refers to "earthshine" which today is dominated by reflected sunlight. But the point of that paper is that right after the collision that created the moon, earthshine was dominated by radiated heat from the Earth, not reflected radiation from the sun, meaning that the earthshine was much more intense than today. The takeaway from the paper is literally the opposite of what your post said:

"The actual study [did] say RADIANT heat from the Earth, [in complete obeyance of the laws of physics], went through the vacuum of space." This radiant heat kept the Earth facing side of the moon molten longer than the far side.

Comment Re:This is stupid ... (Score 2) 143

Reducing a sight in modern celestial navigation usually involves calculating the expected altitude of a target celestial body at a particular time at a particular place on the surface, noting the actual altitude of the body, then using the difference to determine your distance from the reference location. To do that you need to use a time standard that stays in sync with the heavens, or correct for the drift in one that doesn't. UTC is convenient because it's accurate to about a tenth of a second, as close as you could hope to measure by hand, and doesn't need overly frequent adjustment like UT1.

An error of one second in reducing a sight translates to a positional error of around a quarter of a nautical mile, or about half a kilometre. As discussed here a while ago, celestial navigation is still an important backup for military and commercial shipping, as well as deep water private sailors who aren't idiots. A kilometre or two one way or another often doesn't matter, but sometimes it does. GPS, of course, also has to make the same corrections, although it uses finer grained ones than UTC does.

If you're the OP, in regards to your original post, something I don't understand: if you're an astronomer who is noting the timing of astronomical events, why are you using UTC instead of terrestrial time: "a modern astronomical time standard defined by the International Astronomical Union, primarily for time-measurements of astronomical observations made from the surface of Earth?"

Comment Re:This is stupid ... (Score 2) 143

GPS satellites report a time that is a strict offset of TAI, which is the standard that is designed for use by people who don't want leap seconds. GPS positioning depends on the precise position of points on the surface of the Earth underneath the GPS constellation, so although the satellites report a TAI-locked time, to actually determine your position you have to do a correction that's very similar to UTC, except with a granularity that's more like leap nanoseconds instead of seconds.

Comment Re:This is stupid ... (Score 1) 143

There are lots of things that depend on the position of the sun and stars to sub-second accuracy. Celestial navigation, pointing telescopes, pointing satellite dishes.

I don't buy the objections to using UTC. If you can't code a safety critical system for leap seconds, you probably shouldn't be coding safety critical systems. Note that it hasn't been a big problem for the last thirty years, why is it now?

If you REALLY can't deal with leap seconds, use TAI. That's why it exists.

Comment Re:This is stupid ... (Score 1) 143

If you're aiming a telescope, or a satellite dish, or computing an almanac, you care. The point of UTC is that it stays close to UT so that the people who need a time standard that's aligned with the actual rotation of the Earth have something to use. If you don't want to deal with leap seconds, there's already a standard for that. It's called International Atomic Time (TAI), and has been around since the early seventies.

Comment Re:How is it a problem? (Score 2) 143

Heaven forbid developers actually test edge cases....

Another solution would be to use TAI if you really can't be bothered to deal with an occasional leap second. The whole point of UTC is to have a time standard that's based on TAI but is numerically close to UT.

I don't understand why this is suddenly a problem. Perhaps because of all the bootcamp developers writing code now?

Comment Re:Sometimes there are no innocents (Score 3, Insightful) 488

Sure. Except the IS doesn't have any cities. They occupy some territory in Iraq and Syria, where they're mostly bent on executing the majority of the populace. The Nazis would have laughed pretty hard if the allied strategy in WWII was extermination bombing of Jewish neighbourhoods in Paris.

You're absolutely right, the way to attack the islamic state is to attack it's ability to wage war. Stop converting moderate muslims into new recruits, stop littering the area with weapons and political instability, and work towards not giving any more money to oil rich middle eastern dictatorships.

"There are things that are so serious that you can only joke about them" - Heisenberg