Bright spot on Venus Options

[Juramike]

space.com story on mysterious cloud brightening on Venus:
http://www.space.com/scienceastronomy/0907...right-spot.html


...also spotted by an amateur astronomer.

[remcook]

"We know Hubble had been packed solid with use requests and that it was still capable of being re-tasked to get Jupiter images within a week of the first detection of the impact on old Jove."

I suspect it might have been more hard to do if the instrument was already in proper science phase. But perhaps someone would have been willing to give up time...

For Cassini I remember there was a re-design after discovery of Enceladus' plumes by the magnetometer. There were 4 months in between the flybys and I think this was an 'all hands on deck' kind of moment. Maybe John Spencer can tell more about this? The manpower for VEX is a lot smaller, but I suspect if there was really something big going on it would in principle be possible to change the design within a month or so if people put in all efforts (cndwrld?). I'm not sure it makes sense changing the designs in this case since VMC has a whole globe view at least every orbit. I wouldn't be surprised if they saw the entire atmosphere every orbit. What would you change in the observations and is it worth the extra manpower?

[stevesliva]

For Cassini I remember there was a re-design after discovery of Enceladus' plumes by the magnetometer. There were 4 months in between the flybys and I think this was an 'all hands on deck' kind of moment.

From reading the Cassini status reports, the biggest rip-up is changing the trajectory, the second biggest is changing the pointing, and the third biggest is changing the timing. For timing updates, they have whitespace in their plans, for pointing updates they obviously have to throw out the old and begin anew, but they can do this with reasonable speed given proper motivation. A few weeks, I think?? But that is a special request.

[john_s]

The July 2005 Cassini Enceladus flyby was definitely a special case. The decision to change the trajectory to reduce the close approach distance was made in mid-April 2005, just 3 months before the encounter. There was already a fully-developed observation plan, but we only had to tweak the period around close approach (maybe +/- 30 minutes or something like that). It was a scramble, but of course it paid off big time. I don't think we've made a tweak of that magnitude at such short notice since then- usually even the detailed observation sequence is pretty much frozen 4 or 5 months out. I suspect that if there was a big impact on Saturn, say, something could be done to observe it with a lead time of a couple of weeks, but it would be a major effort that would take away from other high-priority planning work- not a decision to be made lightly.

You can be a lot more flexible in planning observations for a spacecraft that can happily sit tight while you figure out your next move, than for a spacecraft that's careening through the solar system at many kilometers per second!

John