A Planet Literally Boils Under the Heat of Its Star 163
The Bad Astronomer writes "Astronomers have found what appears to be a planet so hot it's literally vaporizing, boiling away from the heat of its star. KIC 12557548b was found using the transit method, periodically blocking some light from its star as it orbits around. But the amount of light blocked changes every transit. Given it's less than a million miles from the surface of the star, astronomers interpret this (PDF) as the planet itself turning to vapor, and the expanding cloud of rock-laden gas is what's blocking the starlight. The planet is most likely somewhat bigger than Mercury, but losing 100,000 tons of matter every second it'll only be around another few hundred million years."
Re:Holy cow ... (Score:4, Interesting)
well, think about (hypothetically) zooming out from the Nimitz on Google Earth - how much you have to zoom out even after the Nimitz (all 300 m of it) before you see the full Earth.
Each 1 km x 1km area would pack about 30 Nimitzes. Each 1000 km x 1000 km area would pack about 30,000,000 Nimitzes. And that's just the surface... The Earth is (gasp!) as thick as it is wide, and denser at the center... So yeah. BIG.
As Douglas Adams put it (Score:5, Interesting)
"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space." -- Douglas Adams, "The Hitchhiker's Guide to the Galaxy"
And really, it applies not just to distances, but masses, speeds, etc. As a rule of thumb, if it even deserves being mentioned in astronomy, it's frikken mind-bogglingly big.
The Earth, for example, is 6x10^24 kg, so basically 6,000,000,000,000,000,000,000 tons. Or about 600,000,000,000,000,000 Nimitzes.
Or more to the point of the planet being discussed here, they say it's a little bigger than Mercury, which in turn is 3.3x10^23 kg. I.e., 330,000,000,000,000,000,000 tons.
Yeah, that's the kind of numbers that astronomy is about. Well, not really. These are small planets. Now stars and black holes and galaxies, that's the real bread and butter. And you can pretty much stick the zero key down and go brew some coffee, if you want to write the weights for that.
And then come the distances, yes. Douglas Adams was certainly up to something there.
You know where in Men In Black, agent K says, "You want to stay away from that guy. He's, uh, he's grouchy. A three hour delay in customs after a trip for 17 trillion miles is gonna make anybody cranky." You'd think 17 trillion miles is half-way across the galaxy, right? Actually the nearest star, Proxima Centauri, is 25 trillion miles away. So that alien would have had to make a stop at some cosmic gas station in between, if he only had a 17 trillion miles trip.
It's things like these that... well, let's just say they seriously put the kibosh on most nerds "we should totally do some SF thing right now" scenarios. E.g., since we talk mass, there are all the "oh, let's terraform [insert planet]" stupidities. Yeah, I don't think any of those actually calculated how many trillions of tons of ice comets they'd have to divert into Mars to make oceans and whatever their fantasy scenario involves. (There are 1.4x10^18 tons of water on Earth for example.) Nor where they'd come from, nor what the energy budget for that would be.
Re:Holy cow ... (Score:2, Interesting)
The planet loses mass at a somewhat lesser pace than humanity burns through oil (100,000 vs. 133,000 tons per second). Take that, alien sun!
Re:As Douglas Adams put it (Score:5, Interesting)
I did that once on an RPG forum. I think I was just giving Mars an Earth-like atmospheric pressure from local carbon dioxide and comets assumed to be about the size of Haley's (assumed to all be made of frozen gasses) from someplace in the Kuniper Belt. Anyway, just to get those comets to Mars in ten years would require the total energy output of the sun for three days. Then I started figuring out how big the solar panels would have to be at a really good efficiency and how long they would have to be there to gather that energy. Then there was the question of the mass of those solar panels and where it all came from the the energy needed to construct them. Ya, mindboggling stuff that isn't getting done in our greatgrandchild's time even if we all worked on getting it done from now on. It sort of blew the OPs idea of a near current terraformed Mars right out of the water.
Re:100,000 tons (Score:4, Interesting)
I was born in Perth, Scotland, where g is about 9.82 m/s^2. I now live in Reading, England, where g is about 9.81 --- a small difference, but measurable. If I were to go to Mexico City, it would be 9.78.
There's a wikipedia page [wikipedia.org] with a big table.