Could the remnants of planets be detected when a star goes nova? I would think that there would be traces of elements that would be there that weren't there before.

One explanation which has been seriously proposed (I think it was by Bob O'Dell), to explain cometary knots in planetary nebula, is that they are the evaporating remnants of icy "super-KBO" worlds, made visible only by the star's death throes. In fact, that may be the least silly explanation I've seen...

Any planets that ended up inside the red giant phase of an ordinary star like the Sun would end up getting vaporized, so they'd be gone after a short interval. Outer planets might survive.

As far as supernovas goes, it's hard to say. There would be a lot of energy released, which might be enough to pulverize and vaporize anything nearby. Would it be impossible for anything to survive? I guess that would depend on the size, composition, and distance from the star, and the scale of the SN.

I'd guess that a SN would throw off so much mass that any planet remnant would have a wildly different orbit after the event (since they'd be left orbiting a much smaller object). In some cases the planetary corpse could be ejected from the system entirely.

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"It is quite clear that Occam's razor does not sharpen in your pyramid." (Nicolas)

"Still, a man hears what he wants to hear and disregards the rest." (Paul Simon)

Just last night on The Science Channel, Searching for Alien Planets, they discussed the discovery of a planetary system orbiting the remnants of an ancient supernova.

The rotating neutron star was formed when a binary star system merged and exploded. The planets left behind were described as being "as warm as Earth, but as hospitable as the core of Chernobyl."

I don't imagine any gas giants would survive, but it takes more energy than you think to "vaporize" a solid planet.

Someone has written an extensive paper on the subject complete with physical data and equasions. Google "Star Wars Technical Commentaries" and look up the section on the Death Star. He said you'd need a mass of antimatter the size and mass of a small moon to totally obliterate a terrestrial planet.

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Did they mean pulsar PSR1257+12 and its planets?

The planets couldn't form in their current orbits, so they are most likely post-supernova planets and not remnants of an earlier planetary system.

Perhaps the most promising theory suggests that the progenitor of the neutron star was member of a binary star. It exploded as a asymmetrical supernova which kicked the newly-formed neutron star through its companion. Planets then formed from the debris disk left from the star.

Its (terrestrial!) planets are probably as hospitable as you described, although they are not warm at all despite the fact they orbit the pulsar much closer than Earth.

Funny that the first and most unusual planetary system was the first one discovered, in 1992.

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Ah, but banquo's_bumble_puppy wasn't asking about detecting planetary remnants in the wake of a supernova, (s)he was asking about detecting planetary remnants in the wake of an ordinary garden-variety nova.

So: We start with a planet orbiting a white dwarf that's part of a mass-exchange binary system. No, wait, that wouldn't work, would it? If the planet was close enough to the white dwarf to orbit just the white dwarf, it would also pass through the mass-exchange stream. This would cause enormous aerobraking, thereby sending the planet crashing down to the white dwarf's surface. (Thereby contributing to the next nova outburst. )

Okay, so we'd have to start with a planet orbiting the white dwarf/host star pair at a far enough distance that the two objects act like a point source of gravity. Its orbit would have to be at least, oh, 3 or 4 times the separation distance between the host star and the white dwarf for its orbit to be stable. However, since the two stars are close enough together for the white dwarf to suck material off of the other star, their separation distance probably isn't all that great to begin with. So, a stable-orbiting planet could be reasonably close to the two stars. Assuming that the host star is a red giant that evolved off the main sequence after the white dwarf formed (for how else could a white dwarf be close enough to another star for mass exchange to occur?), we can assume that the separation distance between the two stars is around an A.U. or two. Therefore, let's say that the minimum distance that the planet would have to be orbiting these two stars at would be 4 A.U..

So ... would a planet survive a nova ourburst from a distance of 4 A.U.?

Probably.

I believe it is speculated that Earth will be consumed when our sun dies and I have heard that half of Saturn will be blown away. Maybe Uranus and Neptune might survive, but they'd be pretty dark.

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