Supernovae vs. Planets

[MKruer]

Well I guess what I am getting at is for such an explosion, the actually ejecta should only be traveling at .10-.23c or that's what I have read, however the radiation is moving at the full speed of light. Providing that you survived the initial flash, which would bake you into a crispy critter, you should be able to see the rest of the ejecta coming at you, again providing you are not blind. A Jupiter might be a good place to hide because the magnetic field should afford you some protection against the increase in radiation, however but soon as the ejecta hits, all bets are off.

Does that make sense?

[Fenerit]

Providing that you survived the initial flash, which would bake you into a crispy critter, you should be able to see the rest of the ejecta coming at you, again providing you are not blind.

In that situation I wonder also about the breath, since to the atoms of the atmosphere must be happen something. Either there is an alteration, since such gamma ray/X must be too much and powerful for the ozone layer's circumventing, or the oxygen get burn.

[Hungry4info]

As I understand it, once you detect the supernova, it has reached you.

[ajtribick]

Another thing to question is what happens before the supernova. Assuming we're talking about exploding massive stars rather than exploding white dwarfs, the progenitor would have been a supergiant, that would have been an O-type star on the main sequence (bad for forming planets probably due to intense photoevaporation of disk material)

The largest red supergiants extend to roughly 7 AU. So if pulsar planets are remnants, they would have to be buried deep within the supergiant's envelope before the whole thing went boom. Seems unlikely to me: there is evidence that large gas giants and brown dwarfs can survive immersion in red giants (perhaps resulting in ejection of the red giant envelope and production of a hot subdwarf, e.g. HD 149382), supergiants are much larger, more massive and luminous.

At 10 AU, which is the radius I estimated for unbinding a terrestrial planet, the planet would have been perilously close to the supergiant - even if evaporation of the planet by the supergiant weren't a problem, I'd suspect that gas drag would pull it into the star fairly rapidly.

[MKruer]

I wonder if was is happening in the majority of cases is that a planet is right on the outer limit for the planet to be flung off into interstellar space, but it doesn't quite have enough angular moment to break the now neutron stars gravity and over time if it settles back into a relatively stationary orbit close by.

[Hungry4info]

The planet enters an eccentric orbit, and now may be subject to planet-planet scattering depending on what the orbits of any other planets in the system are like.

[TranslightDefender]

if I did my math right

And

If you had a space ship that had FTL drive

Do not mix.

According to Alcubierre they do.
Wikipedia

[Hungry4info]

if I did my math right

And

If you had a space ship that had FTL drive

Do not mix.

According to Alcubierre they do.
Wikipedia

Alcubierre drive seems unlikely to work (assuming exotic matter exists, which itself is unlikely as well).

http://arxiv.org/abs/0904.0141 (preprint)
http://prd.aps.org/abstract/PRD/v79/i12/e124017 (abstract)

In conclusion, we think that this work is casting strong doubts about the semiclassical stability of superluminal warp drives. Of course, all the aforementioned problems disappear when the bubble remains subluminal. In that case no horizons form, no Hawking radiation is created, and neither strong temperature nor white horizon insta- bility is found. The only remaining problem is that one would still need the presence of some amount of exotic matter to maintain the subluminal drive.

And even if it was possible,

Even if the above described semiclassical instability could be avoided by some external action on the warp-drive bubble (or by some appropriate UV completion of the quantum field theory), the QI lead to the conclusion that the Hawking radiation in the center of the bubble will burn the internal observer with an excruciating temperature of T[sub]H[/sub] > ~ 10[sup]-2[/sup] T[sub]P[/sub], where T[sub]P[/sub] is the Planck temperature, about 10[sup]32[/sup] K. This would prevent the use of a superluminal warp drive for any kind of practical purpose.

[TranslightDefender]

I am aware of the various difficulties with the Alcubierre drive, but my point was that it is possible to apply math when discussing FTL.
There's also wormholes.


Back to original topic, I think a computer simulation of a supernova hitting the planets would be interesting.