Gamma ray bursts are the most powerful events in the universe, surpassed only by the energy discharged when Bob Eggleton leaps onstage to accept a Hugo and does That Thing With His Hair. Astronomers theorize collapsing stars produce black holes, sending gamma rays shooting across space. The bursts are short-lived, much like Arnie Katz’ fanzine titles, so it’s not easy for astronomers to react and make observations. Now NASA has sent the fastest-swiveling space science observatory ever built into orbit, launched November 20, to scan for the “birth screams” of black holes.
“Black hole” is a phrase coined by American John Wheeler in 1968 to describe an object with a gravitational force so powerful that not even light could escape its pull. (Fans who don’t know the difference between a black hole and a neutron star will see that date and be wondering how Larry Niven won a Hugo for something before scientists gave it a name.)
NASA’s new orbital observatory, named Swift for its speedy pivoting and pointing, finally made it off the pad after weeks of delays caused by hurricanes and a three-day postponement due to rocket trouble.
The concept of something like a black hole dates back to the 18th century, when the English and French rivaled each other for world leadership in science as well as war. Either England’s John Mitchell or France’s Laplace first thought of the notion. Historians know Mitchell used Isaac Newton’s theories of gravity and corpuscular light to calculate that a star 500 times larger than the sun would have enough gravity to prevent light from escaping.
Astronomers have never seen a black hole directly, but infer their existence the radiation created as material feeds the object, not unlike the way fans know Bob Tucker is present in a crowded room party, although blocked from view, after everyone suddenly calls out “ Smoooooth!”
In contrast to astronomers, who like to study these things from a safe distance, science fiction writers make their characters drive right up to the edge of black holes and fall in. Of course, for writers this is simply a word picture of their careers as they send manuscripts off to publishers whose interminable response times make it seem like their work has disappeared into a singularity with a New York zip code.
Stories are certainly the easiest way for people to visualize the experience of entering a black hole. Otherwise, what constitutes “falling in” can only be fully understood after years spent studying advanced equations (an unlikely choice among people squandering time by clicking on articles at Trufen.net.) How long does it take to fall in? Ted Bunn answers:
“Let’s say you start at rest from a point whose distance from the singularity is ten times the black hole’s radius. Then for a million-solar-mass black hole, it takes you about 8 minutes to reach the horizon. Once you’ve gotten that far, it takes you only another seven seconds to hit the singularity…. Once you’ve crossed the horizon, in your remaining seven seconds, you might panic and start to fire your rockets in a desperate attempt to avoid the singularity. Unfortunately, it’s hopeless, since the singularity lies in your future, and there’s no way to avoid your future. In fact, the harder you fire your rockets, the sooner you hit the singularity. It’s best just to sit back and enjoy the ride.”
It’s just human nature to poke and prod and try to find out things man was not meant to know. So stubborn astronomers continue to learn all kinds of trivia about black holes. (1) The x-ray radiation emanating from black holes has two components. (2) The Hubble telescope
has detected the noise of gas being slurped into a black hole (and it bears no resemblance to Joe Haldeman slipping into that tub of lime jello; and most remarkable of all, (3) Stephen Hawking and Roger Ebert now agree that nothing escapes from a black hole.
NASA’s Swift observatory is a $250 million collaboration by NASA, Italy and Britain. Unless you think Santa is bringing you one for Christmas, you may have to settle for what you can afford and research black holes the old-fashioned way, by downloading the free board game based on the international Space Very Long Baseline Interferometry Program (SVLBI).