Elsewhere in the galaxy... Earthlings find new planets

By Gwynne Dyer

LONDON (JP): This week: in Europe, a North Atlantic Treaty Organization (NATO) plane mistook a column of Kosovo Albanian refugees for the Serbs who had burned their homes and bombed them, killing dozens. Discussion of this event was not drowned out, oddly enough, by the stunning discovery, simultaneously reported by separate teams of astronomers in Boston and San Francisco, that Upsilon Andromedae's innermost planet is not alone. There are two others orbiting the star as well.

In Asia, Pakistan's ex-prime minister Benazir Bhutto was sentenced to five years in jail for corruption (probably deservedly, though the trial was unfair), and Malaysia's former deputy prime minister Anwar Ibrahim was sentenced to six years for corruption (probably unjustly, and the trial was a joke). In other news, it was learned that Upsilon Andromedae's three planets orbit their sun as closely as Venus, Earth and Mars orbit our own.

In Africa, the many-sided war in the eastern Congo staggered from one indecisive clash to another, and Algeria once again failed to hold an election honest enough to end the civil war that has killed 70,000 people since 1992. Elsewhere in the galaxy, at least 18 relatively nearby stars have been found to have single planets orbiting them since 1995, but Upsilon Andromedae is the first multi-planet system ever discovered (apart from our own).

In the Americas, the Brazilian government lifted a ban on logging in the Amazon, and in Canada the nation held its breath while Wayne Gretzky, the greatest hockey player of his generation, pondered retirement. Earth-based wire services carried no sports reports whatever from any of Upsilon Andromedae's planets, though they are only 44 light-years away.

All right, don't beat it to death. It's understandable that local news will get a bigger play in parochial media like Earth's than even the biggest events elsewhere, and besides there probably aren't any sports reports from Upsilon Andromedae.

All three of the star's known planets are gas giants on the scale of the Solar System's biggest planet, Jupiter -- three- fourths, twice, and four times Jupiter's size, reading from the innermost planet out. Planets that massive, made up mostly of gasses that would be poisonous to carbon-based life like ourselves, are unlikely to be home to anything we would recognize as a sportsman.

Moreover, while Upsilon Andromedae is a sun very like our own, its planet's orbits are very different. Upsilon Andromedae I is even closer to its sun than our own innermost neighbor, Mercury, in a tight 4.6-day circular orbit that makes it impossibly hot for life. Upsilon Andromedae II and III are at Earth-and Mars- like distances from their sun, but swing in and out in highly elliptical orbits that make their surface temperatures vary wildly in the course of a year.

Nevertheless, this really is the news of the decade, or perhaps of the millennium: We Are Not Alone.

"With the discovery of the first planetary system beyond our own", said Dr. Geoffrey Marcy, head of the San Francisco State University team that shared the discovery, "we are witnessing, I think, the emergence of a new era in human exploration." And though nobody has yet found planets able to support our kind of life around other stars, the odds that such planets abound -- and in our own galactic neighborhood -- has now risen to near- certainty.

Scientists have to be conservative in their public speculation about the significance of their work, but this time they can barely contain their excitement.

Only since 1995 have we had any good evidence that our own family of nine planets circling the Sun's warmth was not a unique cosmic accident, explained Dr. Robert Noyes of the other team that shared the discovery, based at the Harvard-Smithsonian Center for Astrophysics. Moreover, all the previous finds were giant single planets. That was not surprising, since existing techniques can "see" only giant planets at these great distances, but "if we find only individual ones, there's a nagging question of 'is it really a planet'?"

They might, instead, be what another astronomer called "failed stars". But Upsilon Andromedae's planets are unmistakably just that: the discovery "really establishes that these are planetary systems in the sense we know and love," added Noyes. What that means, in all probability, is that the entire universe is absolutely rife with life.

Dr. Debra Fischer of the San Francisco State University team put it in more cautious astronomer-speak: "If our interpretation is right and every star like our sun has planets, that really increases the odds (of finding life) a lot."

Evert star has planets? The American teams have scanned over 900 nearby stars in the past few years and found only 18 with planets, including the three-planet Upsilon Andromedae system. They think another of those 18 stars has a second planet, but it may take several more years to be sure because it has a very long orbit: probably 15-25 years. So how does that translate into every star with planets, and many of them suitable for life?

The method they are currently using to find these planets -- careful observation of the tiny wobbles that are produced in the star's own movement as planets orbit around it, followed by complex calculations to figure out the planets' size and orbits -- practically guarantees that they can only find huge planets which are in very close orbits round their stars.

That sort of system, on present evidence, is quite rare, but it is the only kind we can yet see. Smaller, more habitable planets like our own, or gas giants that are in orbits as far out as our own Jupiter, Saturn, Uranus and Neptune, do not produce big enough wobbles in their sun to make their presence known at great distances. If you used the current methods from the distance of Upsilon Andromedae, you would not find any planets around our own sun.

But that doesn't mean they are not there, either in our own case or in several hundred billion others. It will be a while yet before better observational techniques can confirm it, but it's now likely that planets are as common in the universe as grains of sand on a beach -- including several Copacabanas of planets exactly like our own. And since even the interstellar spaces are filled with the organic compounds that are the building blocks of life, most planets suitable for supporting our sort of life probably actually have it.

When I was a child, one of the ways they tried to explain the concept of infinity was to say that if an infinite number of monkeys tapped randomly at an infinite number of typewriters, sooner or later one of them would type out the complete works of William Shakespeare.

But here's a different take on infinity: a galaxy with a hundred billion Shakespeares and Pushkins and Rabindranath Tagores, some writing with claws, and some with tentacles, and some with fingers much like our own. And news reports in a trillion languages about a trillion air strikes, a trillion corruption trials, a trillion retiring sports heroes. Far away from here, but right now.

Of course, I'm only talking about our own galaxy, not the billions of others. But it does put things into a different perspective, doesn't it?