The planet orbits a dim red dwarf star called Gliese 581, and seems to be at the right distance from the star to maintain liquid water on its surface. That, of course, makes alien-philes wonder if Gliese 581g also hosts life. And that makes people want to go check.
Announcing the find on NBC Nightly News, Brian Williams said: "They say it's about 20 light years away, but that's practically nothing in astronomy terms." And he declared at the end of the segment: "It's just nice to know that if we screw this place up badly enough there is some place we can all go."
So they get a couple of folks to do the math, one with a sock-puppet avatar well past its sell-by date, and the answer is either 180,000 years, or three million, depending.
This should be no surprise to those who have already allowed Stross to bum them out about this with his pesky arithmetic. Only marginally related, I've been really enjoying his series on "books I will not write" because of hilarious little asides like
Writing a space opera with FTL means accepting causality violation. And accepting causality violation means computing with closed timelike curves or, in simpler terms, really strong deterministic solutions to P=NP, and then some. Procedural AI hops out of the FTL hat like a demented magician's rabbit and the singularity takes a shit all over your neatly designed Napoleonics-in-Spaaaaaace boardgame table.
Good 100 kg vitrification freezers are probably only a few decades out.
...so that guy somehow decided that a nearly-motionless animated character reading off long strings of numbers in a herky-jerky robotic voice is more accessible or something than reading long strings of numbers in text form, where you at least can skip over the boring parts. Okay.
(captcha: keruzenc n-tuple)
I like Charles Stross more and more.
Writing a space opera with FTL means accepting causality violation.
I think Charlie underestimates the human capacity to ignore inconvenient facts in fictional contexts, which is especially puzzling given that he cites Larry "What Fossil Record? What Genome?" Niven.
You're forgetting that, in orderr to write the thing, it has to make sense to him. And if he can't persuade himself to ignore a little thing like causality violation, or even better, make it part of the story, he won't be able to enjoy the process.
Niven could write Protector and the later Ringworld books because of his ignorance of the biological sciences. And he could sell them because of his audience's ignorance of the same. Us SF nerds are far more demanding these days.
I'm including himself, given how many other gripes his own blog records that he nevertheless puts up with for the sake of enjoying their more felicitous qualities, starting with his cats.
Niven wasn't especially ignorant of the biological sciences; he deliberately mentions Olduvai Gorge for instance, and that kzin and humans must've had some common origin for them to gainfully eat one another, and he in fact had provided such an origin years previous in WORLD OF PTAVVS...but he also sweeps specifics counter to his plot under the rug.
Indeed, I think the ultimate factor is that some people (authors and readers) don't care about putting a paradox under the rug and ignoring it, and some do.
Stross seems like an author who cares more than usual, which is why it's a thorny problem for him. Niven - not as much.
It can be interesting to look at where any author is on that spectrum. Charles Sheffield wrote "Between the Strokes of Night" as an attempt to make something as close to classic space opera as possible without FTL or any other causality violations... the results were an interesting literary/social thought experiment if nothing else. Then you have the other side of the coin, a book like Fallen Dragon by Peter F Hamilton, which is explicitly based on causality violating space/time travel which makes absolutely no sense even on casual inspection. Yet - he's good enough at telling stories you want to avoid inspecting it.
Some authors base their story more in the fantasy camp (who cares about GCV, just look at my cool spaceships!) and some are in the **science** fiction camp. They're both great when written well. And you get both from different kinds of authors.
I think there remain a couple of small dust bunnies under "Palimpsest"'s and _Saturn's Children_'s rugs, not exactly errors but not stuff that supports the appearance of strict physical and internal accuracy,
Larry Niven has a blog? Google isn't helping to locate it, if so.
Stross' LJ I meant, sorry.
...is easy to find. Unfortunately. It's called "Jerry Pournelle's Chaos Manor".