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Goodnight, Philae: Comet probe hibernating with a dying battery

Just two days after the comet landing that easily beat out Kim Kardashian’s behind as far as breaking the internet goes, the Philae lander is powering down after failing to find enough sunlight to charge its battery.

The team behind the landing unfortunately faced one problem after another, beginning with the probe’s twin harpoons failing to fire and anchor it to the comet’s surface. Its thrusters, which would counteract the harpoons to prevent Philae from drifting into space, also failed.

The European Space Agency said Philae bounced twice before settling onto the comet’s surface. Its first bounce lasted 1 hour and 50 minutes; the second 7 minutes. The first touchdown triggered Philae’s scientific instruments, causing it to begin collecting scientific data while it was traveling across the comet’s surface.

Where Philae finally settled was not its intended landing spot. The ESA suspects it instead came to rest by a large depression, or even on its rim.

Wherever it landed, Philae found itself with far less sunlight than it needed to keep its solar-powered battery charged. The original landing site would have provided 7 hours each day; the new spot only receives 1.5 hours, which is not enough to power scientific research. Each day on the comet lasts 12.4 hours.

The first two images from Philae confirmed it safely reached the comet's surface. The probe's foot is visible in the bottom left corner.
The first two images from Philae confirmed it safely reached the comet’s surface. The probe’s foot is visible in the bottom left corner.

With the life of the primary battery running out, the Philae team decided to deploy its remaining scientific instruments to collect as much data as possible. The lander is only anchored to the comet by the screws in its three feet, some of which might not be sitting on the ground at all. Deploying more instruments risked sending the lander back into the air. The ESA opted not to try re-firing the harpoons.

After getting what it needed, the ESA put Philae into hibernation. It is possible it will receive enough sunlight for Philae to reawaken as the comet approaches the Sun.

The good news is that Philae was able to collect enough data to provide scientists with years of work. What they find could help explain what our solar system looked like in its earliest stages, and whether the first water and life on Earth might have been seeded by a comet.

Rosetta, the spacecraft that dropped Philae to the surface, is also still safely orbiting the comet. It will continue to monitor the comet as it passes closer and farther from the Sun.

3 Responses to “Goodnight, Philae: Comet probe hibernating with a dying battery”

  1. Anthony Kock

    I don’t know much about the battery charging process with solar power but Is it possible to Manually keep the probe off so that when it has experienced multiple 1.5 hours in the sun every 12 hour comet day, would the probe harness the energy, gradually increasing until the ESA turns it back on?