Less than two days after its historic landing, Rosetta's probe may be reaching its final hours, and the scientific team is racing to collect as much data as possible before Philae's batteries run out. It's do or die, and at this point there's very little to lose in terms of its lifespan.
As the mission team announced on Thursday, Philae's bumpy landing left it in a shadowy spot. Its solar panels aren't being exposed to nearly enough light to keep the lander going, and it left Earth with only a 60-hour charge. In all likelihood, Philae's batteries will die sometime Friday evening.
And no, we aren't sure where it is.
"We still could not exactly identify where Philae is at this very moment," said Stephan Ulamec, Philae Lander Manager, at a media briefing on Friday morning. He and other scientists hope they'll pinpoint Philae's location with new information they'll receive Friday evening, but by then it may be too late to try to move the probe.
But the probe is doing some speedy science in the meantime: In the media briefing, the Rosetta team said that several new instruments were now operational. MUPUS, which is a penetrator that hammers into the surface, was activated Thursday night. This was a controversial move, scientists worried it might push Philae into an even more precarious position. But with time running out, they made the call to turn the hammer on.
Philae's X-ray spectrometer, which should reveal some clues about the comet's molecular composition, is also running. And as of the team's last contact with the probe (which is interrupted for many hours a day because of the comet's rotation), Philae's drill is also on. We don't know yet whether this tool has actually succeeded in penetrating the surface and taking samples.
The next information from Philae will come around 8 p.m. Eastern time Friday, after the mission team receives its next packet of data from the satellite link. In the meantime, scientists are analyzing the last data packet -- including information from MUPUS -- as we write this.
The next data packet will also include a whole host of new photos.
"We're still awaiting the descent images...and the images from the first touchdown to touchdown plus two hours. These images aren't down yet," said Holger Sierks, who oversees the OSIRIS camera, at the Friday media briefing.
These images are expected to show Philae's bounce, which would help the team figure out where it ended up. "So hopefully...we'll soon be in the position to know where it hides," Sierks said.
It's possible that the team will come up with some way of moving the probe, but this doesn't seem to be their main concern. It's a long-shot, and their time is probably better spent doing as much science as possible before Philae dies. They may try to rotate one of Philae's solar panels the next time they have contact, but the team didn't seem optimistic about the plan during their Friday livestream. Philae isn't askew, it's upright -- so unless the team can make it bounce to a sunnier spot, nothing is going to make it get more light.
The big concern right now is that Philae won't have time to analyze these new samples and send information back before its batteries die later Friday night. The data would be stored in Philae's memory, but there's no telling when, if ever, humanity would get the chance to retrieve it.
"We're cutting it really close to the next link," said team scientist Valentina Lommats during the Friday briefing. It's possible that the battery won't even make it to another link-up with Rosetta, or that scientists will only have time to reach out to the probe -- and not enough for the lander to send back results.
Project scientist Matt Taylor emphasized that Rosetta will still be collecting data for the next year as it follows the comet's orbit. "We've got a year of this...brilliant!" he said at the media briefing.
And maybe, if we're lucky, Philae will have a brief resurgence later in the year. When the comet gets too close to the sun, Philae will be totally toast, and unable to function. But it's possible that as the comet approaches, there will be a brief window when Philae gets more light, but is still able to handle the heat.
"Cross your fingers, or press your thumbs if you're German, that perhaps we might hear from the lander again," Lommats said.