Mercury Flyby 3 Options

[Greg Hullender]

We're now just one Mercury year (88 days) from flyby #3, which happens on September 29, 2009, so this seems like a good time to start a thread about it.

http://messenger.jhuapl.edu/index.php

For comparison purposes, it'd be nice if someone (probably someone on the Messenger team) put together a Mercury Map showing what areas will get better coverage from this flyby than from the previous ones. I realize it'll be very similar to flyby #1, but it won't be exactly the same.

After that, it's a long wait until MOI on March 18, 2011. Curiously, that's the same date the New Horizons crosses the orbit of Uranus.

http://pluto.jhuapl.edu/mission/passingpla...ets_current.php


--Greg

[tanjent]

Galactic cosmic rays could have impacted the spacecraft at any time, regardless of its position relative to the planet.
The fact that this event came just as Messenger entered Mercury's shadow offers a strong hint that it was somehow
related to that transition. That said, I guess some of those 7000+ stored flyby commands could have been corrupted
by a CR incident, and we would not have discovered it until it came time to execute them.

Note - This was WRT Sunspot's earlier post. The subsequent posts are acknowledged with some relief.

[ugordan]

That said, I guess some of those 7000+ stored flyby commands could have been corrupted
by a CR incident, and we would not have discovered it until it came time to execute them.

Commands are not typically as data intensive as science data so it's cheap to have several backup copies of them onboard. That goes for the flight software itself. There are ways very high priority maneuvers can be protected against memory and even processor trips via cosmic rays and several computers with redundant processing is one for example.