I found one paper about comets crashing into the sun, but unfortunately they don’t consider as big comets as you do—the largest one is a “Hale-Bopp sized” one, which they take to be 10^15 kg (which already seems a little low, Wikipedia suggests 10^16 kg.)
I guess the biggest uncertainty is how common so big comets are (so, how often should we expect to see one crash into the sun). In particular, I think the known sun-grazing comets are much smaller than the big comet you consider.
Also, I wonder a bit about your 1 second. The paper says,
The
primary response, which we consider here, will be fast
formation of a localized hot airburst as solar atmospheric gas
passes through the bow-shock. Energy from this airburst will
propagate outward as prompt electromagnetic radiation (unless
or until bottled up by a large increase in optical depth of the
surrounding atmosphere as it ionizes), then in a slower
secondary phase also involving thermal conduction and mass
motion as the expanding hot plume rises.
If a lot of the energy reaching the Earth comes from the prompt radiation, then it should arrive in one big pulse. On the other hand, if the comet plunges deep into the sun, and most of the energy is absorbed and then transmitted via thermal conduction and mass motion, then that must be a much slower process. By comparison, a solar flare involves between 10^20 and 10^25 J, and it takes several minutes to develop.
Most likely the energy will be released below sun’s photosphere, as its density is very low like 1 to 6000 of air. This would prevent immediate flash visibility. The resulting hot gas will flow up eventually but it will cooler and energy less concentrated. But even if it takes several minutes, it still could produce burns on Earth.
Also something like large Solar flash could happen because of integration of the hot gas from the comet with Sun’s magnetic field, and it hypothetically will result in superflare with strong Solar wind and magnetic effect on Earth.
The temperature during impact will be around 5 mln K on the edge of the comet, as I calculated, which is not enough for any meaningful nuclear reactions. But it doesn’t include any additional heating connected with rising pressure because—and pressure would rise as the comet will compress as it decelerate in the solar medium.
If such reaction will happen it could add more energy to explosion and also produce some radioactive isotopes, which could later become part of Solar find and fallout on Earth. I saw an article long time before about possibility of nuclear reaction during impacts, and I will find it.
It sounds pretty spectactular!
I found one paper about comets crashing into the sun, but unfortunately they don’t consider as big comets as you do—the largest one is a “Hale-Bopp sized” one, which they take to be 10^15 kg (which already seems a little low, Wikipedia suggests 10^16 kg.)
I guess the biggest uncertainty is how common so big comets are (so, how often should we expect to see one crash into the sun). In particular, I think the known sun-grazing comets are much smaller than the big comet you consider.
Also, I wonder a bit about your 1 second. The paper says,
If a lot of the energy reaching the Earth comes from the prompt radiation, then it should arrive in one big pulse. On the other hand, if the comet plunges deep into the sun, and most of the energy is absorbed and then transmitted via thermal conduction and mass motion, then that must be a much slower process. By comparison, a solar flare involves between 10^20 and 10^25 J, and it takes several minutes to develop.
I thought more after I posted and concluded that:
Most likely the energy will be released below sun’s photosphere, as its density is very low like 1 to 6000 of air. This would prevent immediate flash visibility.
The resulting hot gas will flow up eventually but it will cooler and energy less concentrated. But even if it takes several minutes, it still could produce burns on Earth.
Also something like large Solar flash could happen because of integration of the hot gas from the comet with Sun’s magnetic field, and it hypothetically will result in superflare with strong Solar wind and magnetic effect on Earth.
The temperature during impact will be around 5 mln K on the edge of the comet, as I calculated, which is not enough for any meaningful nuclear reactions. But it doesn’t include any additional heating connected with rising pressure because—and pressure would rise as the comet will compress as it decelerate in the solar medium.
If such reaction will happen it could add more energy to explosion and also produce some radioactive isotopes, which could later become part of Solar find and fallout on Earth. I saw an article long time before about possibility of nuclear reaction during impacts, and I will find it.