Despite the workload, the MPC staff consists of only 2.5 people, including Marsden, who would like to keep the center running 24 hours a day. But that is not feasible: MPC gets just $130,000 a year from NASA, despite the agency's increased spending on NEO surveys. Other income, from subscriptions and donations, is not enough to cover the 80- to 100-hour workweeks. "Here we are saving the world, and they expect us to do it on our own time," Marsden quips.
More draining than the task at hand, however, is the time wasted on arguments. "There's a lot of infighting in this business. Not everybody likes everybody," he says. Besides the XF11 affair, which soured his relationships with several colleagues, Marsden has taken heat over access to information. He would rather not release data for tentative, single-night asteroid sightings--"one-night stands," as he calls them--both to ensure the data's reliability and to conform to the policies of leading programs such as LINEAR, NEAT and Spacewatch, which do not want unsubstantiated data made public. Astronomers who are anxious to see everything blame Marsden for impeding the information flow. "Brian follows the rules [set by the IAU], but the rules are flawed," Lowell Observatory astronomer Ted Bowell complains. He states that Marsden and others "often post orbital predictions without sharing the data that led to the calculations. I find that scientifically unacceptable."
Despite such criticism, the IAU recently extended the Smithsonian's contract for running the MPC through 2006. As for beyond that, rumors swirl about "hostile takeovers," in Marsden's words. Grant Stokes, who heads the LINEAR program, thinks that moving the MPC to a new home would be a mistake. "Brian and his center service the observing community wonderfully," Stokes says. "It's hard for me to believe this effort could be duplicated elsewhere."
Marsden tries to ignore the squabbles as he looks to the future. One day, inevitably, there will be a NEO on a collision course with Earth. With luck, it will be small and won't cause much damage. If it is spotted years or decades in advance, there might be time to intervene. "This is one threat we can do something about," he declares. Various defensive strategies have been proposed, including nudging an approaching asteroid with a nuclear blast or darkening part of the object's surface so that the thrust produced by radiated heat changes its orbit. Marsden is not sure how much money should be spent exploring these options but insists that "we have to do more than the dinosaurs."
Until now, the focus has been on large asteroids, a kilometer or bigger. The goal of the Spaceguard Survey, funded mainly by NASA, is to find 90 percent of these objects by 2008. More than 650 asteroids have been identified so far, perhaps half the total. (Astronomers estimate the total based on discovery rates from previous surveys.) Still, Marsden remarks, "we should begin planning the next step." Looking for 200- to 300-meter-wide objects is often proposed as a sensible target, but that would require new telescopes and roughly 10 times as much money.
Marsden turns 66 this month and would eventually like to hand the reins over to MPC's associate director, Gareth Williams, his partner since 1990. There's no timetable for a transition, says Williams, who admits he has "very big shoes to fill. Brian has been preeminent in the field since the 1960s." NASA Ames astronomer David Morrison, chair of the IAU's NEO working group, also lauds Marsden's efforts. Given Marsden's long tenure in the NEO field--starting out as he did when there was no "field" to speak of--Morrison is skeptical about talk of his impending retirement: "I think he'll do it forever." That is, of course, if the world doesn't end first.