APOD: Animation: Black Hole Destroys Star (2021 Apr 27)

Comments and questions about the APOD on the main view screen.
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MarkBour
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Re: APOD: Animation: Black Hole Destroys Star (2021 Apr 27)

Post by MarkBour » Fri Apr 30, 2021 6:45 pm

neufer wrote:
Thu Apr 29, 2021 4:03 am
https://en.wikipedia.org/wiki/Hulse%E2%80%93Taylor_binary wrote: <<The Hulse–Taylor binary . . .

The minimum separation at periastron is about 1.1 solar radii; the maximum separation at apastron is 4.8 solar radii. The orientation of periastron changes by about 4.2 degrees per year in direction of the orbital motion (relativistic precession of periastron). In January 1975, it was oriented so that periastron occurred perpendicular to the line of sight from Earth.

The total power of the gravitational waves emitted by this system presently is calculated to be 7.35 × 1024 watts. For comparison, this is 1.9% of the power radiated in light by the Sun. With this comparatively large energy loss due to gravitational radiation, the rate of decrease of orbital period is 76.5 microseconds per year, the rate of decrease of the [~3 solar radii] semimajor axis is 3.5 meters per year, and the calculated lifetime to final inspiral is 300 million years.>>
That's really amazing. They're so close and the forces are so huge! I guess that will result in incredible violence, ending in a short gamma-ray burst .
Mark Goldfain

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neufer
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Re: APOD: Animation: Black Hole Destroys Star (2021 Apr 27)

Post by neufer » Fri Apr 30, 2021 11:40 pm

MarkBour wrote:
Fri Apr 30, 2021 6:45 pm
neufer wrote:
Thu Apr 29, 2021 4:03 am
https://en.wikipedia.org/wiki/Hulse%E2%80%93Taylor_binary wrote: <<The Hulse–Taylor binary . . .

The minimum separation at periastron is about 1.1 solar radii; the maximum separation at apastron is 4.8 solar radii. The orientation of periastron changes by about 4.2 degrees per year in direction of the orbital motion (relativistic precession of periastron). In January 1975, it was oriented so that periastron occurred perpendicular to the line of sight from Earth.

The total power of the gravitational waves emitted by this system presently is calculated to be 7.35 × 1024 watts. For comparison, this is 1.9% of the power radiated in light by the Sun. With this comparatively large energy loss due to gravitational radiation, the rate of decrease of orbital period is 76.5 microseconds per year, the rate of decrease of the [~3 solar radii] semimajor axis is 3.5 meters per year, and the calculated lifetime to final inspiral is 300 million years.>>
That's really amazing. They're so close and the forces are so huge!
I guess that will result in incredible violence, ending in a short gamma-ray burst.
It's never too soon to sell off your gold before the market plunges.
Art Neuendorffer