Slashdot Mirror
Cassini Can See Cleary Now
EccentricAnomaly writes: "Well, it looks like Cassini's camera problems have been fixed according this story at CNN and this Cassini mission status report. The haze first appeared on the camera lens somewhere between Jupiter and Saturn. Personally, I can't stand it when I get crud on my windshield -- especially when I'm 750 million miles from home."
Now only if you could type clearly as well.
"And like that
Page 1 : PLUTONIUM POWERED PROBE COULD KILL BILLIONS IF EXPLODED ON TAKEOFF
Page 7 : It didn't.
Page 1 : EARTH COULD BE HIT BY PLUTONIUM PROBE FLYBY AND KILL EVERYONE
Page 9 : Missed us.
Page 1 : BILLION DOLLAR PLUTONIUM PROBE BLINDED
Page 11 : We fixed it.
I was hoping this was Beverly Cleary. I want another Mouse and the Motorcycle book.
What'dya mean there's no BLINK tag!?
The reason why not? Moving parts. There is a taboo on moving parts, in as far as they can be avoided. Moving parts can jam in the most inconvient places, rendering an instrument useless. In this case, if a wiper got caught midwipe, all the subsequent pictures would have that wiper in the middle of the image. Sort of like fingers in vacation photos, but way more expensive.
1) It would destroy the optics. You would get scratches and the finish (anti-reflection coating and such) would also be scratched away. Basically you don't want any mechanical contact with optics.
2) There's no space for wipers when the condensate is somewhere within the lens system and you would need a seperate wiper for each surface.
3) The surfaces of optics are not flat but probably spheric or have some different form. It would be difficult to build a wiper for that geometry.
NASA anticipated the problem - see the paragraph about lens heaters in the mission update referenced in the story.
Not quite windshield wipers, granted, but the agency did anticipate the problem from ealier experience, and built in a solution that had worked before and which worked this time, too.