No one said it would be easy to conduct scientific experiments robotically on Mars. And in fact the Phoenix Mars Lander continues to run into nagging problems. What’s very interesting is how engineers working with scientists on Earth are developing workarounds to solve the problems. It’s engineering at its best, and it reminds me a little of the steps taken on the ill-fated Apollo 13, although the Mars mission is not life-or-death.
In the latest problem, soil dumped on a screen is clumping, and not passing through to analysis equipment, even after vibration. Engineers decided to employ a motorized rasp on the scoop that was actually designed to dig out granite-like ice below the polar surface. Tests show that the scoop, when tilted, does drop fine particles of soil while it is being vibrated by the rasp. Previously, the scoop was just dumped outside down, dumping the soil.
Look for tests in a few days that will chemically analyze the soil.