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It was the other guy’s fault, no question. That’s pretty much the explanation for why a major science conference scheduled for December came close to being torpedoed. Astronomers from all over the world were planning to gather at NASA’s Ames Research Center, in Mountain View, California, to talk about new results coming from the planet-hunting Kepler mission. The spacecraft was pronounced more or less dead in August, but there’s still extraordinary new science coming out of its backlog of archived observations of newly discovered planets orbiting distant stars—and the best may be yet to come.

But in September, Ji Wang, a postdoctoral student in astrophysics at Yale, got an email saying he couldn’t attend. The reason, it turned out: Public Law 113-6, Section 535, subsection b, passed by Congress last spring. NASA was forbidden to use any funds “to effectuate the hosting of official Chinese visitors at facilities belonging to or utilized by NASA.”

It’s understandable that Congress is worried about the security of research centers that house any of America’s high-tech secrets. Those kinds of intellectual assets have plenty of peaceful purposes, but they also have military ones, and countries that fail to guard them carefully do so at their peril. What’s more, the clause’s author, Virginia Congressman Frank Wolf, took particular note of a Chinese scientist named Bo Jiang, a NASA contractor nabbed on his way out of the U.S. last March with a NASA-issued laptop. Sure enough, Bo had unauthorized information on the computer—though it was porn and illegal movie downloads, not defense secrets. But clearly there was good reason to worry about what the next guy might steal.

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That didn’t cut it with Debra Fischer, though, the head of Yale’s exoplanet research group, or with the others on her team. “’This guy is like my brother,’” Fischer recalls another postdoc saying of Ji. “’I’m in no position to be boycotting meetings [at this point in my career], but if he can’t go, I won’t go either.’”

Fischer’s entire group decided to skip the meeting—a big loss for the conference, considering that she’s one of the world’s pre-eminent planet hunters. By then, word was spreading through the astronomy grapevine. “Geoff Marcy [a co-investigator for the Kepler mission] asked for details,” says Fischer, “and when he heard what was going on, he said ‘this isn’t right.” Both Marcy and Fischer had been at San Francisco State University (he was a professor, she a grad student) when Mario Savio, hero of the 1960’s-era student Free Speech Movement returned to school for a master’s degree in physics, and, says Fischer, “he made a big impression on us.”

Shortly afterward, Marcy announced he’d be boycotting the meeting as well—and if Fischer’s absence would hobble the conference, Marcy’s, given his status as the world’s greatest planet-hunter by far, with at least 250 previously unknown worlds to his credit, would more or less destroy it. The conference organizers couldn’t move the meeting off NASA property, in part because the venue was free, while an off-site location would cost a small fortune. But if the big guns didn’t show up, it would be a huge embarrassment for all concerned.

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It was at this point that the scrambling began. Wolf put a letter on his website saying NASA had misunderstood the law; it wasn’t any Chinese citizen who was banned from NASA facilities, he said. It was just representatives of the Chinese government or of Chinese corporations who were banned.

But Wolf couldn’t just clarify: he had to scold as well. Reacting to Marcy’s declaration to The Guardian newspaper that the ban would be an “ethical breach that is unacceptable. You have to draw the line,” Wolf wrote, “I hope Dr. Marcy will draw a similar line when it comes to cooperation with Chinese government funded agencies and programs due to their systemic human rights abuses. In fact, as a Nobel nominee himself, has he publicly advocated for the 2010 Nobel Prize recipient Liu Xiaobo who to this day languishes in Chinese detention?”

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Once Wolf denied that he or his law bore any responsibility for the mess, says Fischer, “The finger of blame pointed to [NASA administrator Charles] Bolden. Then Bolden sent an email saying mid-level management at Ames was the culprit for reading the law wrong.”

Last Friday, says Fischer, Ji got an email informing him that his clearance was approved. The meeting will go on, with Fischer’s team as well as Marcy’s and representatives from most other planet-hunting groups there to announce and chew over new results. In the end, Fischer thinks the entire matter was indeed something of a misunderstanding, though one from which both scientists and national security officials must learn. “Now I think it was an unintended consequence of other stuff going on. I don’t think they were actually trying to exclude our postdoc. But if we hadn’t reacted the way we did,” she says, “the organizers might have looked the other way for the ‘greater good’ of science.’” The toll on fairness and common sense would have been another matter.

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