Mercury Flyby 2 Options

[Holder of the Tw...]

It is time for this new topic.

Round Two

[Mariner9]

I was reading an article on Spacedaily, and ran across this real mathematical puzzler:

"Observations during this second Messenger flyby will almost complete the first high-resolution viewing of Mercury, adding another one-third of the planet surface to the 21% of territory not seen by Mariner 10 and first imaged by Messenger in January 2008," says Messenger Project Scientist Ralph McNutt.

I'm scratching my noggin over this one.
He appears to be saying: Mariner 10 + Messenger Flyby 1 = 21% unimaged, aka. 79% coverage.
But if you add another 33% coverage, you get 112% coverage, which can't be correct.

Or, perhaps: Mariner 10 + Messenger Flyby 1 = 79% Coverage. Of the 21% left unimaged, Flyby 2 will get 1/3 of that missing coverage, aka 7%, so the total coverage will go up to 86%.

Anyone want to chime in?

[JRehling]

Mariner 10 viewed 45% of Mercury. By these numbers, Flyby 1 added 21% and Flyby 2 added 33%, summing to 99%. That works. I think 33% is a bit of an overstatement, but speaking in fractions, 29% could be the real figure, giving a total of 95%.

I still think that's an overstatement, or at least it includes areas on the limb which aren't really being effectively resolved, but the gist is that we'll see more new stuff this time than we did last time. And when it's done, we'll have viewed the great majority of Mercury's surface.

The catch is that it looks totally different depending on phase angle, so we're going to have to see everything at least twice before we've really seen it. But the orbital mission will ace that assignment.