Death Stars, Gamma Ray Bursts and Black Holes

[aTOMiC]

After watching the NOVA episode “Death Star” I find my sense of security shaken. The subject of gamma ray bursts is interesting enough. Learning about the techniques used to identify their origin was fascinating. The theories developed by the astronomers studying the phenomenon were remarkable. Learning about the mechanics of the death of a giant star and the subsequent birth of a black hole was very entertaining. The amount of gamma radiation released during one of these events is astounding. That we can detect the gamma bursts originating in other galaxies throughout the universe is mind-boggling. I was very impressed until came the punch line. What if an event such as this occurred in our own galaxy? What if said event occurred in our galactic neighborhood? These scenarios were explored in an impressive animated graphic that adeptly depicted the immediate destruction of all life on our planet. Nice. It was also theorized that these rather common cosmic explosions might be systematically eradicating all life within the effected radius of their destructive influence. So much for meeting extra terrestrial life, eh? It was noted that there were no stars that might be candidates for this kind of event currently within range of our solar system so I may be able to fall asleep tonight. I have included a link to the companion web page to the NOVA episode. Enjoy.

www.pbs.org/wgbh/nova/gamma/

[dANdeLION]

Wow; I was unaware that the Gamma radiation emmited by the Death Star's planet-smashing ray could cause a black hole!

[aTOMiC]

Wow; I was unaware that the Gamma radiation emmited by the Death Star's planet-smashing ray could cause a black hole!

Brilliant observation, dAN. You are adept at blurring the lines of fiction and reality.

[dANdeLION]

And all in the name of shameless self-promotion and the almighty post count, no less.

[aTOMiC]

And all in the name of shameless self-promotion and the almighty post count, no less.

Watch it, bub. Here comes another gamma ray burst!

[matrixman]

Wow; I was unaware that the Gamma radiation emitted by the Death Star's planet-smashing ray could cause a black hole!

I was not aware of this either. Maybe Mr. Lucas will include a new sequence showing this weird physics in action in the Extra Special Edition of Star Wars. In 3-D. (Okay, maybe not.)

Er, back to the real physics...

Good topic, TOM C! I caught that episode of NOVA, too. All these years I had thought that the biggest conceivable explosion in the cosmos was a supernova. Wrong! I can't begin to fathom the colossal power and scale of a HYPERNOVA. (Though I am now a little surprised that this very impressive phenomenon wasn't used in a Star Trek episode...or was it?)

Anyway, to complement this topic, I'd like to share a speculative end-of-earth scenario I've read about that pairs up nicely with the "death by gamma ray burst" calamity. In this case, it's the destruction of Earth caused by collision with a black hole. Here's what would happen if by some unbelievably bad cosmic luck a two-solar mass black hole were headed toward Earth:

Black Hole Apocalypse

The killer black hole was formed somewhere in the disk of our galaxy from the death of a massive star. It rushes through space toward Earth at several kilometres per second. The first indirect hints of the approaching monster come millenia before the actual collision. As the black hole passes through the Oort cloud (the population of comets surrounding the Sun), it throws the comets into chaos and snags a host of them into orbit around itself. Centuries before the black hole's arrival, astronomers notice sizeable changes in the orbits of the outer planets as they respond to the black hole's gravitational influence. It becomes quite clear to the astronomers that this intruding object is no ordinary star, for a two-solar mass star arriving in the Oort cloud would appear as bright as a streetlight a few blocks away.

Telescopes trained on the black hole report bizarre fluctuations in the brightness of background stars and galaxies. Viewed from afar, a black hole acts like a lens because its gravity warps space-time so that it magnifies and distorts the images of objects lying in the line of sight. Stargazers will take temporary pleasure in the amazing precision provided by this black hole "telescope."

As the black hole crosses the orbit of Pluto, the planets deviate wildly from their normal courses. Jupiter and Uranus are captured by the black hole, while Saturn and Neptune are flung out to deep uncharted space.

From Earth's vantage point, the black hole approaches from the opposite side of the Sun. The combined gravity of the Sun and the black hole pull Earth through a distorted version of an ordinary year. In a matter of weeks, the Sun draws closer to Earth than at any other time in 4.6 billion years of terrestrial history. As the Sun scorches the continents, Antarctic ice melts and swamps the coastal cities. Hurricanes of unprecedented force rage over the seas. A stunned humanity wrestles with its collective fate.

The end arrives quickly. Through a telescope, the black hole looks like a psychedelic comet, surrounded by faintly glowing gas and warped images of background stars and galaxies. In the final hour, real hell breaks loose. As the tidal forces of the black hole take hold, the side of Earth facing the black hole is pulled with greater force, and the planet becomes grossly deformed. Earthquakes rock the surface. 6,7,8,9...the Richter scale becomes meaningless. The planetary crust rips apart along old fault lines, and patches of solid rock float on the scorching lava of the deforming planet. Earth is pulled like taffy into a disk of vaporized rock which forms a whirlpool in its stampede to enter the black hole. The energy released during the final demise is visible far beyond the galaxy.

With only a million or so stellar black holes in our galaxy, the chance that a black hole will collide with Earth is far too low for concern. Odds of a direct collision are about 1 part in 1 x 10^26 per year. This scenario is purely for fun, if perverse fun.

[aTOMiC]

That was very interesting, MM. I need a cool Earth-end scenario for a book I'm writing. Hmmmm.... Black hole eh? Leave it to nature to come up with a doomsday scenario to rival that of the best Hollywood screen writers. Long live the earth! I think we'll all miss her when she's gone. Kind of puts all our petty problems in perspective.