Hubble Discovers 'Planetary Graveyard' Around White Dwarf 26
astroengine send this interesting excerpt from Discovery: "The Hubble Space Telescope has discovered rocky remains of planetary material 'polluting' the atmospheres of two white dwarfs — a sign that these stars likely have (or had) planetary systems and that asteroids are currently being shredded by extreme tidal forces. Although white dwarfs with polluted atmospheres have been observed before, this is the first time evidence of planetary systems have been discovered in stars belonging to a relatively young cluster of stars. 'We have identified chemical evidence for the building blocks of rocky planets,' said Jay Farihi of the University of Cambridge in a Hubble news release. 'When these stars were born, they built planets, and there's a good chance that they currently retain some of them. The signs of rocky debris we are seeing are evidence of this — it is at least as rocky as the most primitive terrestrial bodies in our Solar System.'"
Re: (Score:1)
whooosh
Re:don't get it (Score:4, Interesting)
It says a relatively young cluster of stars. That doesn't mean that some members of the cluster aren't old enough to have gone nova. Also, larger hotter stars (than the Sun) don't stay in the main sequence nearly as long, so it's possible that some were just under the threshold to become neutron stars. There is no contradiction there.
Re: (Score:2)
Also, larger hotter stars (than the Sun) don't stay in the main sequence nearly as long, so it's possible that some were just under the threshold to become neutron stars. There is no contradiction there
Very true. One of the things that always seemed counterintuitive, but obvious from a physics perspective, is that there are stars which have formed, burned insanely bright, and 'died', within the age of the Earth, let alone our Sun.
poor science reporting (Score:2, Interesting)
The article doesn't explain why there is rocky material close enough to the white dwarfs to be tidally ripped apart. It makes a brief comment about the extreme tidal stresses ripping apart anything orbiting it. But superdense objects don't exert stronger gravity for their mass than less dense objects. If the sun spontaneously magically became a white dwarf, or even a black hole, the earth would continue in its orbit unperturbed. The only thing that would cause a former planet of this white dwarf to be tidal
Re: (Score:1)
...choosing rather to go down the bad science "it's denser so it must magically suck harder because that's how gravity really works" route.
Could you quote the passage in question? I read the article and didn't see anything saying that. They did say, "Any planetary system that was once in orbit around the star will be severely disrupted during the red giant phase...", which while less explicit is more or less what you said the article "mentions none of".
Too bad for any life (Score:3)
Re:Too bad for any life (Score:4, Interesting)
that's probably the answer to the Fermi Paradox. For billions of years the earth had life, but only in the last few decades the technology that *might* have detected or made a signal to another star. In less than 350 million years, the earth will be too hot to support multicellular life due to expansion of the sun. what if every billion years or so an intelligent species arises within 10,000 light-years of any other place that has the same thing happen once at some random time over the life of the universe? they find themselves alone...
Re: (Score:1)
You made the erroneous assumption that species' survival is tied to the life of their home star.
Re: (Score:2)
I made the logical conclusion that will be the case in most cases. any exceptions will be too far from us to matter.
Re: (Score:2)
nasa.gov says only a few million years for us or anything descended from us
you make the mistake of seeing a time span for any kind of single cell extremophile life surviving, might still be possible in a billion years as the earth's temperature approaches boiling. But two and four legged land creatures will be long gone in half that time
Re: (Score:3, Insightful)
You put too much faith in our ability to detect other civilizations.
Who says they would be using technology noticeable to us?
Who says we'd even notice them with a 150 year delay between their actions and our ability to perceive them?
We know too little about how things work in space to draw any meaningful conclusions. Best to stop at, "Apparently, we saw nothing. Damn. Next section of the sky, please."
The universe is too big for us to be completely alone. The only question is: are they in range for us t
Re: (Score:2)
If there was life there that escaped the current destruction it had to have left millions (or billions) of years ago (since the star has been a white dwarf for a long time and has been being obnoxious to its inner planets for a long time also). That means they would have likely colonized near space (not at all limited to our own solar system). Keep in mind that even the Voyager probes, which aren't even designed to go to other stars will reach nearest stars on the order of 100,000 years. And systems using
Re: (Score:1)
well it's actually a good point, our ability to detect something would depend on how much energy it expended, therefore crossed the galaxy in a way we could detect it.
small scale example, a computer in the 50's took a whole building, generated a ton of heat and noise, people walking past easily could detect something was there, even if they didnt know what it was, standing inside the main room was hot and the air dry, all easy to detect.
nowadays, computers use a tiny fraction of the power they used to and a
Aw,... (Score:4, Funny)
Re: (Score:2)
I have a bad feeling about this...
Re: (Score:1)
Kryten you smeg head! I said red dwarf, not white dwarf!
Zombie planets (Score:2)
All I know is if they have zombie humans, cats, wolves and other such critters than they must inevitably also have zombie planets. Now one would assume that zombie planets munch on the brains of other planets, but the unfortunate thing is that this isn't covered in any of the zombie survival guides! Locking yourself in a nice zombie proof chamber isn't going to do any good when the planet next door comes gobbling away you know.
Let's face it, your going to need a really, really big gun and how can you possib
Woo hoo! (Score:3)
Spare parts to keep our planet running longer!
Slashdotted (Score:1)