What About This…? 1.7.2015

By Wayne William Cipriano

I am sure it is because I was never much of a math wizard that feats of astrophysics and calculus impress me much more than they may impress you. But exactly like you, on Nov. 12, 2014, I held my breath in anticipation as spacecraft Rosetta and it’s Philae probe met Comet 67P/C-G and we all waited to find out if the lander (probe) found its way down successfully.

After a truly incredible voyage, a spacecraft about the size of a pickup delivered a package of electronic and mechanical miracles about the size of a dishwasher to a hunk of rock and dust and perhaps water ice about the size of Ava moving at 41,000 miles per hour.

To reach 67P/C-G, the European Space Agency (ESA) used a powerful rocket and the gravitational pull of the Earth three separate times to increase the speed of Rosetta and probe Philae (R/P), and then it whipped around Mars once more before it began chasing 67P/C-G, finally catching it exactly where and when predicted.

There had been a few glitches. The largest one was the failure of so many rockets slated to carry R/P that by the time ESA felt confident enough to put R/P on one of them, the comet they initially decided to visit had moved too far away to reach.

They looked for a substitute and the best they could find was so far out that there was a power problem, not enough sunlight would reach R/P to fully power it. So, they put R/P “to sleep” for two years and seven months to conserve as much power as possible hoping that when R/P reached P67/C-G it would awaken.

And it did! Although, like all who understand drama, R/P waited an extra eight hours before at last saying “good morning.” It had travelled over four billion miles, over a ten-year period, thirty-one months of which it was completely out of touch, and it ended up exactly where it was supposed to be –– 320,000,000 miles from Earth, 60 miles from the comet, and ready for duty.

ESA now got to see what 67P/C-G looked like using state-of-the-art cameras from ten years ago that have the resolution of cell phone cameras today.   It was most weirdly shaped and, of course, spinning. Two and a half miles wide, six miles long, and shaped like a Wellington boot with a ball balanced on its toe.

A landing site had to be selected with Goldilocks sunlight (not too much, not too little, just right), and few big boulders to upset R/P’s landing. When that was done, Philae was released to be drawn down very slowly by P67/C-G’s very weak gravity. When Philae landed, the screws designed to dig into the comet’s surface and hold it down did not work, the harpoons and cables to do the same thing did not deploy. Philae bounced about six miles up. Then, it fell back and bounced again, not so high. It fell back a third time landing at a very problematic angle, possibly due to a large boulder, and in a shaded area. Not much has happened since then.

Should we say then that this mission was bereft of success? Perhaps so, if we believe as does our daughter Raquel that only perfection is acceptable.

But remember, a spacecraft was launched ten years ago, travelled four billion miles to reach a target we selected at the last moment, with so little power that it had to “hibernate” the last two-and-a-half years, and did indeed set down on that spinning comet.

And, today that spacecraft, starved for power, almost frozen solid, 320,000,000 miles from us, waits for some sunlight that may yet provide enough electricity to once again transmit “good morning.”

If that is not some sort of success, what would you call it?