After Four Days, Philae Team Gets to Rest

The Associated Press reports on one happy consequence of the inevitable shutdown of the Philae lander, after its incredible landing on Rosetta: the team that was in control of the lander here on earth finally gets to take a well-deserved break, after four nearly sleepless days and nights. It seems unlikely -- though it's not impossible -- that Philae will get enough solar energy to briefly wake up again; its bouncy landing and harpoon malfunction mean that the craft is in shadow rather than the sunlight that it was hoped to bask in. From CNN: Originally, it was supposed to have seven hours of light per comet day -- which lasts just 12.4 hours. Now it is exposed only 1.5 hours a day. That's likely not enough to juice up Philae's rechargeable secondary battery, ESA said. There is one last hope. "Mission controllers sent commands to rotate the lander's main body, to which the solar panels are fixed," ESA says in on its blog. "This may have exposed more panel area to sunlight."

Comments

Re:Questions for any who have been following this

[confused one]

It's not quite that simple. It takes a certain amount of power to keep the computer running, even in low power standby mode. It also requires some energy to run the onboard heaters, which keep the battery and electronics from failing due to the extreme cold. The amount of energy they were receiving in the 90 minutes, before the attempt to turn the probe, was insufficient to supply the heaters, run the computer in low power standby and charge the battery. I don't know if they left the heaters running, because there was concern that the heaters alone were enough to prevent the battery from charging. If not, the battery may freeze solid before charging to a level that's able to restart the computer. It's hoped that that won't be the case... we'll have to wait and see.