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Ilustration of view from a distant world
The discovery of new planets in the outer reaches of the solar systems could help give planetary astronomers new respect among their peers and the public. (credit: NASA, ESA and Adolf Schaller)

When I’m not in prison I’m an astronomer

Believe it or not, there is a pecking order among astronomers. One would have assumed that once they graduated high school, finally escaping the jocks and the other alpha males (and females) of social hierarchy, and then acquired ridiculously expensive educations in arcane disciplines, astronomers would become a pretty egalitarian community of nerds. But this is not quite true.

There is a weird social hierarchy among astronomers where the more amorphous and abstract the subject, the higher the status of the people who study it. Within the astronomy community the cosmologists rank at the top. Their studies rely almost entirely on mathematics and they rarely bother to look through a telescope because they’re too busy trying to use equations to prove the nonexistence of God. Below them come the observational astronomers who deal with all the things that feed into cosmology, the people who study the interstellar background and black holes and quasars—mostly things that cannot really be seen but have to be inferred indirectly. Slightly below them are the people who study galaxy formation. Next are the people interested in stellar formation—mere stars. If you read astronomy publications closely you will occasionally spot the black hole people dissing their colleagues who are interested in such irrelevant subjects as how a star forms out of dust and gas.

Way down at the bottom of the hierarchy—the proles, so to speak—are the planetary astronomers, the ones interested in studying planetary formation, or worse, finding asteroids and comets. They get the least respect from their colleagues, even though—or perhaps because—their research is often the most publicly accessible. The attitude of the other astronomers is that there’s no point to studying solid objects. You might as well be a geologist. The offices of astronomy departments around the country are frequently filled with gripes that somebody is wasting valuable observing time on the Hubble looking at rocks.

Planetary astronomers get the least respect from their colleagues, even though—or perhaps because—their research is often the most publicly accessible.

In the early 1990s, when David Levy found the comet whose name he shared with the late great Eugene Shoemaker, he was fond of griping that he could not find a job as an astronomer. Now he is a pretty good general space reporter for Parade magazine. However, until recent decades, when the federal government’s annual funding for astronomy projects rose to the billions of dollars, it was not easy to find work as an astronomer at all. (And for those who wonder, the title of this article is taken from the opening line of a real job application that was once submitted to the National Research Council’s Board on Physics and Astronomy. That person is presumably still looking for work.)

This pecking order is reflected in official policy, and there has even been affirmative action for planetary astronomers. Planetary astronomers had to fight to have the Hubble Space Telescope designed to enable it to conduct more planetary observations. Even today, within the astronomy community there is a certain amount of griping about the Terrestrial Planet Finder (TPF), a large space telescope planned for sometime in the next decade with the goal of locating Earthlike planets orbiting other stars. There are many problems with the TPF plans and timetable, but from a social standpoint it has been interesting to watch as the telescope’s proponents received a boost after President Bush announced his Vision for Space Exploration and then have quietly been put back in their place as the astronomy community argues about the nonimportance of discovering life elsewhere in the universe—especially when the Big Bang has yet to be explained.

Now, though, the planetary astronomy community has an opportunity to make a breakout move. Maybe they will not get the respect of the cosmologists, but they can certainly become the public’s superstars of the astronomy field.

The recent announcement of the discovery of an object larger than Pluto in a highly eccentric orbit is simply the latest (and most blatant) example of a number of recent planetary discoveries hinting that we may be on the verge of a paradigm shift in our understanding of our solar system. The astronomers who discovered it have nicknamed it “Xena” after the Sapphic warrior princess who had her own television show a few years ago. They have submitted their find to the International Astronomical Union, which is the final arbiter of all astronomical finds, and proposed a name for it that is probably not “Xena.”

Demoting Pluto is like shooting yourself in the foot with a shotgun. After all, what’s the point—other than a scientifically pedantic one—of relegating your field to lesser status?

What is unclear, though, is whether or not the IAU will designate this new object as a “minor planet” or a “major planet.” The IAU, unsurprisingly, has a complicated set of rules that the public knows little about. Its committees make a distinction between “minor planets”—asteroids, comets, etc.—and “major planets.” However, they do not all agree on where the precise distinction line should be drawn. When Pluto was discovered back in 1930 it got dumped into the “major planet” category, something that some IAU members now think was a mistake. In fact, some IAU members have argued in favor of demoting Pluto to “minor planet” status.

This is like shooting yourself in the foot with a shotgun. After all, what’s the point—other than a scientifically pedantic one—of relegating your field to lesser status? At the very least, Pluto should remain a “planet” simply because of the fact that it was located with some relatively primitive instruments. That alone testifies to the significance of Clyde Tombaugh’s achievement.

But the latest find of “Xena” indicates that there may be objects larger than Pluto out there in the void. If Pluto is a planet, then certainly everything larger than Pluto is a planet too. And why not? Wouldn’t this dramatically increase the appeal of astronomy in general and planetary astronomy in particular? The possibility of finding and naming a comet attracted a lot of people to the field back in the 1990s. The possibility of finding and naming a planet may be equally attractive.

Professional astronomers will admit that amateurs have contributed to the discipline, not only by providing a labor supply, but also because of the simple fact that there is so much sky out there that many eyeballs are needed to look at it. Of course, the people at the top of the astronomy hierarchy might (quietly) sniff at this idea. The types of questions they want to answer require Ph.D.’s and big, expensive instruments, not an eight-inch Meade or (shudder) Celestron telescope on a tripod in somebody’s backyard, manned by a 13-year-old girl and her little brother.

But while some parts of astronomy are becoming ever more arcane, other parts are becoming more democratic. The Large Synoptic Survey Telescope, which is still in the drafting stage but may eventually be located in Chile or Mexico, will have a wide field of view enabling it to survey the entire visible sky in three days. It will do this automatically, and its data will be dumped onto a public website where anyone can access it. As new objects are discovered by the software, it could be an amateur equipped with a computer who makes a major discovery.

We may be entering an era when we no longer define our solar system as nine (or so) planets and many lesser bodies, but perhaps twelve, fifteen, or even twenty planets in wildly different orbits.

Like what? Well, one of the newest theories of solar system formation that is currently circulating, and gathering a little momentum, is known as oligarchic planet formation. In this theory, dust particles gradually accumulated into planet-size bodies, perhaps sixty of them. Eventually some of these accumulated into the gas giants we see today. But the intriguing aspect of this theory is that there may be a dozen more planets larger than Mars or even Earth that were flung into highly eccentric orbits and are currently circling our sun way out there in the void, high above the plane of the ecliptic. While the members of the IAU are gearing up to argue over whether or not Xena—or Pluto—are planets, the discovery of even larger bodies may throw the entire field into substantial reexamination. We may be entering an era when we no longer define our solar system as nine (or so) planets and many lesser bodies, but perhaps twelve, fifteen, or even twenty planets in wildly different orbits.

That’s an opportunity if ever there was one. The planetary astronomers should stop arguing over Pluto, name Xena—or whatever it is going to be called—the tenth planet, and seize the limelight.


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