Thursday, March 7, 2013
Curiosity Powers Down...
It's a precautionary measure, now that Curiosity is running on the alternate computer. They're taking the precaution because of a giant solar flare headed toward Mars...
So God Made a Dog...
This is a takeoff on Paul Harvey's famous piece “So God made a farmer”. Guaranteed to warm the heart of any dog lover, including the non-believers...
Mercury Map...
I remember Mariner 10, when it returned the first photos from Mercury – grainy, black-and-white, and seemingly miraculous. At right is an example of those first photos. Now we have this incredibly detailed image that's chock full of information encoded in those false colors, revealing the kinds of geology over the entire planet's surface.
What a Bug!
The programmer made a common error: converting a floating point “double” to a 16 bit signed integer (a “short”).
For my non-programmer readers, this is a little like trying to use a quart jar to store water, then transferring it to a drinking glass. It works fine if your quart jar only has a little water in it, but if the quart jar has more water in it, that water won't all fit in the drinking glass. In this case, it's the numeric value that won't fit. For example, if that double had the value 200,000 in it, the short would end up with something very different – the biggest number it can hold is 32,767 (don't ask why unless you really want to get into the weeds!).
So the programmer made this noobie error. Most of the time, the consequence of this sort of error is just a “Aw, crap!”, and the programmer fixes it. This time the consequence was the loss of $500 million dollars – because it blew up an Ariane 5 and its cargo.
Major bummer...
For my non-programmer readers, this is a little like trying to use a quart jar to store water, then transferring it to a drinking glass. It works fine if your quart jar only has a little water in it, but if the quart jar has more water in it, that water won't all fit in the drinking glass. In this case, it's the numeric value that won't fit. For example, if that double had the value 200,000 in it, the short would end up with something very different – the biggest number it can hold is 32,767 (don't ask why unless you really want to get into the weeds!).
So the programmer made this noobie error. Most of the time, the consequence of this sort of error is just a “Aw, crap!”, and the programmer fixes it. This time the consequence was the loss of $500 million dollars – because it blew up an Ariane 5 and its cargo.
Major bummer...
Whittle on Voter Fraud...
Bill Whittle has a knack for clearly articulating common sense political observations. I listen to him every time I see one of his videos published. This one is particularly biting, while nevertheless managing to sneak in some of his trademark humor along the way...
Giant Arapaima...
Awesome...
Layers of Fact-Checkers...
ABC News mis-labels Iraq on the map in this broadcast – as Iran. What exactly was your complaint with bloggers, again?