5 ms·

"Catalysmic Variable Star" is a good name! :) https://en.wikipedia.org/wiki/AM_Canum_Venaticorum https://en.wikipedia.org/wiki/AM_Canum_Venaticorum Both of th

"Catalysmic Variable Star" is a good name! :) https://en.wikipedia.org/wiki/AM_Canum_Venaticorum https://en.wikipedia.org/wiki/AM_Canum_Venaticorum Both of the stars stars are white dwarves, a mass of a sun squeezed into the size of a small planet. With a 17-minute orbit, they're incredibly close: one of them is ripping the atmosphere off of the other. Helium from the lighter dwarf is being pulled off and falling onto the more massive one -- pulled so strongly, it impacts the surface at several percent the speed of light. A helium layer builds up, at temperatures and pressures close to that of the interior of a hydrogen bomb. And at some point it does go off, like a hydrogen bomb -- a thermonuclear detonation the size of a planet, the entire surface igniting almost simultaneously. And this keeps repeating!

Someone 12y ago
Couldn't resist; I had to check that "size of a planet" claim: 2.7 * 10^36 erg in tons TNT gives me (on Google) 6.45315488 × 10^19 tons TNT. The area of Earth is around 5 × 10^8 km^2. So, 'planet size', that's about 10^11 tons TNT per square km, or 2,000 Tsar Bomba's per square km (Tsar Bobma was around 5-6 × 10^7 ton TNT equivalent). Volume-wise, it would be about one Tsar Bomba per cubic kilometer of Earth. So yes, I guess you could call that planet sized.
- throwaway_yy2Di 12y ago
  More simply, the white dwarf star is the size of a planet, and its entire surface is detonating all at once. :)
- techdragon 12y ago
  Well, when you work out the size of a few numbers regarding Tsar Bomba, I'd be more than happy to call those numbers indicative of planet sized. For instance. The TNT equivalent of the 50 Mt test could be represented by a cube of TNT 312 metres (1023 feet) on a side, approximately the height of the Eiffel Tower. Which when you carry with your numbers, means that more than 9 (3^3) but much less than than 64 (4^3), (excuse the massive lack of accuracy but I'm doing a fermi estimate here, it seems appropriate) which are both massively less than 2000, which means that, the explosion you would get if you covered the earth with a 10Km 'crust' of TNT, would still not be bigger than this star when it goes off. Id definitely call that planet sized.

Someone 12y ago

Couldn't resist; I had to check that "size of a planet" claim: 2.7 * 10^36 erg in tons TNT gives me (on Google) 6.45315488 × 10^19 tons TNT. The area of Earth is around 5 × 10^8 km^2. So, 'planet size', that's about 10^11 tons TNT per square km, or 2,000 Tsar Bomba's per square km (Tsar Bobma was around 5-6 × 10^7 ton TNT equivalent). Volume-wise, it would be about one Tsar Bomba per cubic kilometer of Earth. So yes, I guess you could call that planet sized.

throwaway_yy2Di 12y ago
More simply, the white dwarf star is the size of a planet, and its entire surface is detonating all at once. :)
techdragon 12y ago
Well, when you work out the size of a few numbers regarding Tsar Bomba, I'd be more than happy to call those numbers indicative of planet sized. For instance. The TNT equivalent of the 50 Mt test could be represented by a cube of TNT 312 metres (1023 feet) on a side, approximately the height of the Eiffel Tower. Which when you carry with your numbers, means that more than 9 (3^3) but much less than than 64 (4^3), (excuse the massive lack of accuracy but I'm doing a fermi estimate here, it seems appropriate) which are both massively less than 2000, which means that, the explosion you would get if you covered the earth with a 10Km 'crust' of TNT, would still not be bigger than this star when it goes off. Id definitely call that planet sized.