How to pwn a planet

Reuters (and many other sources) are reporting that astronomers at CalTech may have been pressured by hackers to reveal their discovery before they had completed their analysis.

I must have missed this statement when I first read about the planet, but I think this is pretty interesting. Apparently attackers had compromised a "secure server" and determined that the astronomers had made this discovery, and threatened to make the information public if the researchers didn't do it themselves. It makes me wonder what they got access to. I'm betting it was email, because I'm not sure I'd buy the idea that they'd be able to make sense of the scientific data itself. Anyone know?