Mission designer is at top of his game Peers are boggled by his orbital dexterity


Imagine throwing out three runners in a single, sublime baseball moment.

Now imagine a triple play while the ball, the runners, the bases and the stadium are all in outer space, each moving in its own peculiar orbit.

That's pretty much what Robert Farquhar has promised for NASA's $154 million Comet Nucleus Tour (CONTOUR) mission, scheduled to visit three comets after a July 2002 launch.

The effervescent mission designer at the Johns Hopkins University's Applied Physics Lab plans to rocket CONTOUR into a series of loops tens of millions of miles out in space, each with a snap-the-whip boost from Earth's gravity into the next loop.

Three of those orbits will carry the craft to close encounters with comets. It will buzz Comet Encke in 2003, Comet Schwassmann-Wachmann-3 in 2006 and Comet d'Arrest in 2008, just as the ancient ice balls arrive from deep space to swing around the sun.

And Farquhar says the 1,900-pound spacecraft could remain on call for more comet flybys at least through 2031. Its trajectory, he says with a typically unabashed pride, "is the best one I've ever come up with."

Farquhar is an astrodynamicist, the grand master of celestial maneuvers at APL in Laurel. He and a team of APL scientists and engineers were chosen in the fall to plan the CONTOUR mission, to design and build the spacecraft, and to control its flight. The venture's principal investigator is Cornell University astronomer Joseph Veverka.

"A lot of people are brilliant," Veverka says. "But I have met a small number of individuals who are able to do things that are to me incomprehensible. In this particular field, Bob is one of those people. Somehow, in his head, he can figure out whether one of these trajectories is possible."

But even admiring colleagues add that Farquhar can be an exasperating and impish self-promoter. He indulges penchants for numerology and for mixing science with sentiment in ways that can rile image-conscious NASA brass.

Farquhar regularly finesses his missions so they begin, climax or end on red-letter days, birthdays and anniversaries, or dates involving the number 12.

While planning APL's Near Earth Asteroid Rendezvous mission -- headed for a January 1999 rendezvous with the asteroid Eros -- Farquhar calculated the perfect date to end the mission in 2000.

After NEAR orbits Eros for a year, "he wants to land the sucker on February 14," says an incredulous Donald Yeomans, senior research scientist at NASA's Jet Propulsion Laboratory. "Valentine's Day! On Eros, the god of love! This is going way over the top."

Farquhar, 65, can hardly believe he gets paid to have so much fun. A white-haired veteran of several heart attacks, he remains super-charged by his work, with a keen competitive edge.

He doesn't look the part, in open-collared dress shirts, pocket protectors, dress slacks and conservative shoes. His small office is well-ordered and spare.

Off the job, he immerses himself in the postal history of 20th-century Manchuria, writing articles and collecting its stamps. "Really!" he says.

Farquhar grew up on Chicago's South Side and haunted that city's Museum of Science and Industry. He was fascinated by airplane designs. "I was flunking my drafting courses," he says, but he designed and built airplane models.

Farquhar slipped through high school in the bottom 40 percent of his class but graduated from the University of Illinois with honors in aeronautical engineering. Later, he earned a master's in engineering from UCLA and a doctorate in astronautics from Stanford.

Taught to anticipate what might go wrong on an airplane, he is a reluctant, superstitious passenger. "I try not to sit in any seat with 13 on it," he says.

Twelve is OK, though. He has this thing about numbers.

"He'll work and worm until he finds a launch date or an encounter date that happens to be his birthday [Sept. 12], or his wife's. He'll work to see that something is divisible by 12," says Yeomans, who has worked for him.

"I drive some people nuts," Farquhar admits. Faced with an ambiguous choice, he'll round it off at 12. "I don't have to vacillate so much," he explains.

He says the "12" thing began with the 1978 launch of the International Sun-Earth Explorer -(ISEE) satellite. ISEE was the first ever sent to hover in the "L1" point -- the "sun-earth libration point," a million miles sunward from Earth. That's where the gravitational pull on spacecraft by the sun and Earth cancel each other out.

ISEE was launched at 12 minutes, 12 seconds after the hour on Aug. 12, aboard Delta rocket No. 144 (12 squared).

"That just happened," he says.

But it's his doing that the NEAR mission will officially complete its orbital operations at Eros on 2/6/00. "Two times six is 12," he says, a twinkle in his eye. It's also the anniversary of both his marriages.

Veverka says Farquhar's numerological bent is "a game; he knows this is something that will get attention and get some reaction from his colleagues."

Still, Veverka added: "If I had to guess, I think in back of it there is a little bit of superstition."

Farquhar's sentimentality led him to have two asteroids named for his wives -- Irina, and the late Bonnie Farquhar. And when he announces key mission dates, Yeomans says, somebody asks the inevitable: "OK, Bob, whose birthday is that?"

Farquhar gets away with these and other stunts he doesn't dare publicize because he is extraordinarily good at what he does.

"He's an idea man," Yeomans says. "He'll have 100 ideas, 99 of which may not be reasonable. But that last one is a beaut. And he does this routinely. He's one of the very best, and he's recognized as such even by people who compete with him."

And he can make enemies.

"Bob is a very poor loser, and an even worse winner," Yeomans says. "He has a tendency to gloat, and that may rub some people the wrong way."

Veverka says Farquhar is not arrogant, but "if he gets a particularly good idea, he gets very proud of himself and forgets about all this modesty."

"Bob is the master of getting to places," he says. Farquhar's ideas have helped APL win a growing list of NASA contracts. Yeomans grumbled that all three of APL's proposals in the last round of NASA funding won final consideration. Only two of the Jet Propulsion Laboratory's 20 ideas made the cut.

Farquhar's fascination with astrodynamics began in 1957, when the Soviet Union launched Sputnik I, the first artificial satellite.

"I liked rockets and this was cutting edge," he says. It led to his dissertation in 1968 on how NASA might fly a spacecraft to L1.

Today, sentinel spacecraft at L1 give Earth an hour's warning of electromagnetic blasts from the sun. Others at a spot called L2 explore Earth's geomagnetic "tail." That's where the solar wind sweeps back the planet's magnetic field, like long hair swept back by a gale.

"People thought I was crazy, because the points are not stable," Farquhar says. But with -ISEE, in 1978, he proved it could work.

In 1971, he proposed sending a communications relay satellite to orbit a libration point beyond the moon. Had NASA gone for it, Apollo 17 astronauts could have landed on the back side of the moon and remained in constant radio contact with Houston.

Instead, they endured radio blackouts whenever they flew behind the moon. And the moon's far side remains unexplored.

The comet bug bit him in 1974, and he proposed ways to sail twin spacecraft through the coma and tail of Comet Encke during its 1980 return. That idea never flew, but Farquhar persisted.

In 1982, NASA scientists were refused money for a U.S. mission to Halley's Comet. The $500 million tab was too steep. The Russians, the Japanese and the Europeans had missions planned, but the Americans were staying home.

Farquhar then proposed that -ISEE -- still measuring the solar wind at L1 -- be diverted to a comet called Giacobini-Zinner. Farquhar said he could do it at a fraction of the cost of sending a new craft.

Better still, it could get there six months before everyone else got to Halley. "It's no fun being second," Farquhar says.

"People who had experiments on board the spacecraft were not happy," Yeomans says. "It was perceived to be a wild, foolish idea to take a functioning spacecraft that was doing good work for some harebrained idea to send it to a comet."

But then Farquhar's team told NASA brass that ISEE could be steered to study Earth's geomagnetic tail while en route to the comet. NASA went for it.

Farquhar confesses he sold the idea before he actually figured out how to pull it off. At one point, he says, it seemed it would not work. "I thought 'What am I going to tell these people?' "

Designing complex orbital trajectories is like tunnel excavation, he says. You know where the ends of the tunnel will be. The problem is getting the two holes to meet inside the mountain.

Farquhar knew where the satellite (renamed ICE, for International Comet Explorer) was. And he knew where it had go to intercept Giacobini-Zinner. His challenge was devising an orbit that would fling it around Earth with the precise speed and direction needed to reach the comet.

The solution turned out to be the most complex spacecraft maneuver he, or anyone else, had ever devised. Sketched out, it resembles a pile of discarded shoelaces.

After repeated lunar flybys and dips into Earth's magnetic tail, ICE was finally flung toward its rendezvous. On Sept. 11, 1985, it zipped through the comet's tail.

ICE wasn't ideal for the work, but it returned valuable data. It also upstaged the foreign Halley missions to become the first spacecraft ever to visit a comet. And, it cost just $3 million.

Farquhar's peers are as boggled by his orbital dexterity as laymen. Many assume he uses some fancy computer program, he says. But his answer is no: "I say, 'I figured it out on a little piece of paper.' "

Others can do the math, but "Bob is the only one who understands these problems almost intuitively," Veverka says. While his office computer idles, Farquhar does orbital mechanics on paper. Then he passes the idea to his assistant, David Dunham, who runs computer simulations. From there, it's trial and error.

"He [Dunham] does all the work, and I take all the credit," Farquhar says with a laugh. He avoids the computer work because ultimately the solutions depend on "intuition and creativity."

Farquhar is already conjuring ways to use CONTOUR after its planned mission ends on Sept. 12, 2008 -- his 76th birthday.

He says there should still be enough fuel on board in 2012 for a return encounter with Comet d'Arrest. It could also reach Comet Encke in 2013 "to see how things have evolved" since the 2003 flyby.

If NASA wants to go, there could be more comet flybys in 2015, 2018, 2023 and 2031, he says.

He believes CONTOUR will be ready. It will snooze between encounters, spinning like a top to remain stable. It will carry plenty of thruster fuel, plus solar panels and radio antennae that work in any position.

By 2031, CONTOUR will be more than three decades old, but "I'm sure it will still be working," Farquhar says. His own fate is less certain. "I'll be 99."

Yeomans, at rival JPL, quoted his secretary's quip on that question: "Only the good die young. Bob will still be going strong."

Pub Date: 1/19/98

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