Death Star fired at a star.

[Kuroneko]

The gravitational binding energy of a star is 10e41, a trillion times more powerful than 1 superlast shot

You have a strange numeric format. The binding energy of the sun is on the order of 1e41J, not 10e41 = 1e42J. [Edit (Dec '07): this statement is incorrect. Not that a single order of magnitude matters much to the points raised here, but I've recently adapted this model to MATLAB, and so was reminded of this thread. It turns out that hastier calculation at the time of this post was off, and the more correct number of 6.1e41J is actually closer to 1e42J. I doubt anyone cares about this issue after such anymore, but here's a correction regardless.]

And where is the proof of this claim that CME would not harm the deathstar?

The term is a misnomer in this case, since such a blast would definitely break the outer layers of the star, thus not being 'coronal'. In any case, while it would certainly be much more powerful than any natural CME, one would expect it to be on about the same magnitude as the Alderaan explosion simply because most of the energy will be provided by the shot. While the stellar matter is already at a higher energy state and a bit of stray fusion might occur, this shouldn't increase the Death Star's exposure unduly assuming a similar distance from the event (or greater).

[Ender]

If material did indeed blow off the sun, what effect would it have on the Death Star?

None whatso ever. The first Death Star survived getting pasted with the debris from Alderaan. This is significantly more momentum and energy then one would see from a CME. Particularily the energy part, in fact its mroe then the power of the entire star.

are you saying the deathstar could literally fly into a star without damage?

From the energy of the star, sure. However when it comes down to two colliding bodies, the DS is smaller and will lose.

And where is the proof of this claim that CME would not harm the deathstar?

That would be the movie. The Death Star would have been hit with about 8*10^31 joules from an omnidirictional explosion. It also would have been hit with with a force of ~1*10^24 newtons. Both of these values are far far higher thent he energy or force of a CME.

[Kuroneko]

That would be the movie. The Death Star would have been hit with about 8*10^31 joules from an omnidirictional explosion. It also would have been hit with with a force of ~1*10^24 newtons. Both of these values are far far higher thent he energy or force of a CME.

The so-called "CME" resulting from a DS shot into a star would be around the same order of magnitude as the Alderaan blast by conservation of energy. Comparing this with an ordinary coronal ejection event is silly, since they are relatively weak compared to the superlaser. The DS will survive simply because it survived Alderaan, not because the "CME" is weaker.

[Ender]

That would be the movie. The Death Star would have been hit with about 8*10^31 joules from an omnidirictional explosion. It also would have been hit with with a force of ~1*10^24 newtons. Both of these values are far far higher thent he energy or force of a CME.

The so-called "CME" resulting from a DS shot into a star would be around the same order of magnitude as the Alderaan blast by conservation of energy. Comparing this with an ordinary coronal ejection event is silly, since they are relatively weak compared to the superlaser. The DS will survive simply because it survived Alderaan, not because the "CME" is weaker.

You are assuming that it will result in the blast returning, or causing a direct liftoff. However, the power and force of the beam mean that, unless it strikes at the proper angle to hit the core, the blast penetrating though and continuing on is more likely.

[Wyrm]

In any case, while it would certainly be much more powerful than any natural CME, one would expect it to be on about the same magnitude as the Alderaan explosion simply because most of the energy will be provided by the shot. While the stellar matter is already at a higher energy state and a bit of stray fusion might occur, this shouldn't increase the Death Star's exposure unduly assuming a similar distance from the event (or greater).

Would there be a columnating effect because the shot would be pumping energy into a rough cylinder in the stellar atmosphere, thus the Death Star experiencing more backwash than from blowing up an Earth-sized planet (whose energy would be spread evenly in all directions)?

[Lukedanieljames]

From the energy of the star, sure. However when it comes down to two colliding bodies, the DS is smaller and will lose.

but the sun is not dense, the deathstar would sink into it like thick pea soup,
are you saying the deathstar could sit inside the star for aslong as the food doesn't run out?

this sounds absurdly stupid

[Ender]

From the energy of the star, sure. However when it comes down to two colliding bodies, the DS is smaller and will lose.

but the sun is not dense, the deathstar would sink into it like thick pea soup,

The sun is actually very dense, a fact that was covered on the first page.

are you saying the deathstar could sit inside the star for aslong as the food doesn't run out?

The DS's shields held out against getting hit with energy on the scale of 10^31 joules. Steady state output of a G type yellow star is 10^26 watts. So while not indefinately, and dependent on how well the heat exchangers work inside there, yes it could sit there for a very long time.

this sounds absurdly stupid

I'm explaining to you that 31 is greater then 26. How do you think it looks to me?

[Kuroneko]

The so-called "CME" resulting from a DS shot into a star would be around the same order of magnitude as the Alderaan blast by conservation of energy. Comparing this with an ordinary coronal ejection event is silly, since they are relatively weak compared to the superlaser. The DS will survive simply because it survived Alderaan, not because the "CME" is weaker.

You are assuming that it will result in the blast returning, or causing a direct liftoff. However, the power and force of the beam mean that, unless it strikes at the proper angle to hit the core, the blast penetrating though and continuing on is more likely.

There is that, but I think you're overstating the situation considerably. Let's see if we can set some bounds on this 'punching through' effect. I'll assuming 10% stellar radius, which is only about five Earth diameters. That's not particularly significant considering the scale and violence of the Alderaan explosion, especially since this is a low-density environment. In the region 0.90 < r < 0.99, the solar density is ρ(r) = 2.0008r²-4.0726r+2.0712 g/cm³, making the average density in this region μ = 1.0708e-2g/cm³. For stellar radius R = 6.9598e10cm and cross-sectional beam area A, this means the beam will interact with a mass of 0.09RμA = [6.7e7g/cm²]A, more of the top 1% is counted. That assumes completely radial path, which is a lower bound. For an upper bound, the trajectory should be tangent to r = 0.90 sphere, i.e., it becomes a sector chord c with apothem a = 0.90 and sagitta s = 0.09 (again, the top 1% is ignored), c = 2[(a+s)²-s²]^{1/2} = 0.82. The upper bound is then (cR)μA = [6.1e8g/cm²]A.

Now, let's compare this with an Earth, with radius R = 6.371e8cm and mean density μ = 5.515g/cm³. Assuming A<<4πR², the beam interacts with at least 2RAμ = [7.0e9g/cm²]A. We know that the superlaser should fail to go through this amount of matter. The case of Earth and top 10% of the Sun are only one or two orders of magnitude apart, particularly in the case of the off-radius shot. Just as another comparison, the radial shot for Luna has 1.9e9 as the coefficient, which is even closer. I believe this makes it quite reasonable that the superlaser will deliver most of its energy in the top 10% of the sun should it be fired there.

Would there be a columnating effect because the shot would be pumping energy into a rough cylinder in the stellar atmosphere, thus the Death Star experiencing more backwash than from blowing up an Earth-sized planet (whose energy would be spread evenly in all directions)?

I don't believe there would be much of that. Perhaps somewhat surprisingly, the above analysis also shows that some non-radial shots into stars are more dangerous to the surrounding system than radial ones, simply because the energy will be delivered closer to the surface, but an non-radial shot should also cause the energy to be more directed away from the Death Star.

[SirNitram]

To give an example of the ease by which SW-level shields allow one to sit in a star...

Power Intensity at surface of star(Ruthlessly stolen from Mike's Science section): ~ 6E7 W/m²

Profile of a TF Core Ship(Excluding comm towers): 655,785.86 m²(Rounded to 655km to make my life a little saner)

Energy absorbed by TF shields, assuming 100% transfer of energy: ~3.9E14W

Or.....

A pathetic fraction of a percent of the TF Core Ship's 6e23W peak shield generation.

The DS1 profile: 80,424,770 m^2(Rounding to 80,000 km to make my brain stop hurting)

Energy absorbed by DS1 shields, assuming the same 100% transfer: 4.8e15W

Now, I'll sit back and wait for someone to correct this horrible crime against mathematics.

[Manus Celer Dei]

<Snipperoonie>

NecronLord did some similar calcs for the core ship in may which are within an order of magnitude of yours, so I wouldn't say they're a "horrible crime against mathematics"

[Kuroneko]

To give an example of the ease by which SW-level shields allow one to sit in a star... Power Intensity at surface of star(Ruthlessly stolen from Mike's Science section): ~ 6E7 W/m²

That's about right for the Sun, yes.

Profile of a TF Core Ship(Excluding comm towers): 655,785.86 m²(Rounded to 655km to make my life a little saner) Energy absorbed by TF shields, assuming 100% transfer of energy: ~3.9E14W

The kilometer conversion doesn't work. 655,785.86 m² = 0.6558km². In any case, [6e7W/m²][6.56e5m²] = 3.9e13W, not 3.9e14W. Even less.

A pathetic fraction of a percent of the TF Core Ship's 6e23W peak shield generation.

Well, that depends just where in the star this occurs. For example, according to the above-mentioned stellar simulation the temperature is T = 1.580e7K at the core. I'm assuming that the shields will effectively protect the ship from conductive heat transfer, so that the only relevant part is radiation. Now, normally, radiative transport is comparatively small, since every part of solar matter would try to radiate about as much energy as it absorbs from elsewhere. However, in this case a cool object is suddenly embedded in the core, the radiation intensity on it will be on the order of σΤ^4 = 3.5e21W/m². Conclusion: the ship's shields cannot effectively protect an object of surface area over 170m².

[SirNitram]

Profile of a TF Core Ship(Excluding comm towers): 655,785.86 m²(Rounded to 655km to make my life a little saner) Energy absorbed by TF shields, assuming 100% transfer of energy: ~3.9E14W

The kilometer conversion doesn't work. 655,785.86 m² = 0.6558km². In any case, [6e7W/m²][6.56e5m²] = 3.9e13W, not 3.9e14W. Even less.

And this is why my posts are crimes against math.

A pathetic fraction of a percent of the TF Core Ship's 6e23W peak shield generation.

Well, that depends just where in the star this occurs. For example, according to the above-mentioned stellar simulation the temperature is T = 1.580e7K at the core. I'm assuming that the shields will effectively protect the ship from conductive heat transfer, so that the only relevant part is radiation. Now, normally, radiative transport is comparatively small, since every part of solar matter would try to radiate about as much energy as it absorbs from elsewhere. However, in this case a cool object is suddenly embedded in the core, the radiation intensity on it will be on the order of σΤ^4 = 3.5e21W/m². Conclusion: the ship's shields cannot effectively protect an object of surface area over 170m².

The calculations were done for the photosphere; in my bumbling way, I forget to mention that, I guess.

I imagine for being in the core, there'd be more than just heat transfer and radiation to worry about.

[Darth Wong]

In the core, the physical pressure would crush the ship.