The comets on very remote regions of the Oort cloud have very slow proper motion like 0.1 −1 km per sec. I initially thought that they would fall directly into the Sun if perturbed but AI claims that this will not happen—need to check more.
Radiation in Miyake events can be explained by magnetic flares up to some extend
With some Googling, I found a simple formula. Assuming an ideal elliptical orbit, the distance at perihelion is v2/2g, where v = velocity at aphelion and g is the gravitational acceleration there. For this distance to be the radius of the Sun, we get v=1r√2GMR, where G = gravitational constant, M = mass of Sun, R = radius of Sun.
At r = 10000 AUs, this is 0.27 metres per second. At 100,000 AUs, 0.027 m/s — or 1 inch per second. Despite the Sun’s attraction, it’s still a small target at that distance.
Yes, ChatGPT said me that most Sun-grazer comets are interacting with Jupiter first and and only several cycles of interaction the comet has a chance to hit Sun. This is a good news as there will be less silent killers.
See Effective Potential for a useful tool that lets you pretend things are just moving radially. When you have something far away and want to know its closest approach, you just need its energy (kinetic+potential) and its angular momentum. To get something to hit the sun, you don’t just need its velocity to be small, you need its angular momentum to be small, which is hard because that grows linearly with distance from the sun.
The comets on very remote regions of the Oort cloud have very slow proper motion like 0.1 −1 km per sec. I initially thought that they would fall directly into the Sun if perturbed but AI claims that this will not happen—need to check more.
Radiation in Miyake events can be explained by magnetic flares up to some extend
With some Googling, I found a simple formula. Assuming an ideal elliptical orbit, the distance at perihelion is v2/2g, where v = velocity at aphelion and g is the gravitational acceleration there. For this distance to be the radius of the Sun, we get v=1r√2GMR, where G = gravitational constant, M = mass of Sun, R = radius of Sun.
At r = 10000 AUs, this is 0.27 metres per second. At 100,000 AUs, 0.027 m/s — or 1 inch per second. Despite the Sun’s attraction, it’s still a small target at that distance.
Yes, ChatGPT said me that most Sun-grazer comets are interacting with Jupiter first and and only several cycles of interaction the comet has a chance to hit Sun. This is a good news as there will be less silent killers.
See Effective Potential for a useful tool that lets you pretend things are just moving radially. When you have something far away and want to know its closest approach, you just need its energy (kinetic+potential) and its angular momentum. To get something to hit the sun, you don’t just need its velocity to be small, you need its angular momentum to be small, which is hard because that grows linearly with distance from the sun.
Yes, but somehow large Kreutz comet came recently close to Sun, so there should be a mechanism which makes it more likely.