[X] My Assistant

[Guest_PhilCo126_*]

Certainly worth a look:

http://www.newscientist.com/blog/space/200...ever-flown.html

[dvandorn]

The problem with this concept is not just that we're comparing apples and oranges -- we're comparing apples, oranges, bananas, pears, strawberries and kumquats.

Apples: Doing *anything* first earns you a special place in a list like this -- which is why the lack of Luna 9, Lunar Orbiter 1, Luna 16 and Lunakhod 1 are somewhat glaring. Sounds like the author of the piece just plain isn't interested in the Moon, and therefore delegates lunar probes to a back seat. In a time when Apollo hadn't happened, the first good images of the Moon from the surface and from orbit were powerful, compelling, and scientifically important. There are tons more of these in this category -- Mariners 2, 4, 9 and 10, Lunas 2 and 3, Surveyor V... and many more than don't come to mind at the moment.

Oranges: Making major discoveries certainly distinguishes a mission. The Voyagers, Mariner 2 and Cassini certainly stand out in this category. So do the MERs. The Viking landers aren't at the head of this list, though -- they belong in the Apples group, but while they returned a lot of interesting data (and some great images), they didn't make any amazing new discoveries about the Martian surface. We already knew it was iron and sulphur rich, and there was nothing particularly surprising about finding a lot of iron-rich lavas covered with sulphate salts. The hydration/oxygenation in some of the materials was predictable, so even its (somewhat ambiguous) discovery wasn't all that much of a major thing. Mariner 9 and the Viking orbiters told us more about Mars than the landers did.

Bananas: Observing stars (our own and others) and celestial phenomenah is worth a mention, too. From OAO to WMAP, from OSO to Ulysses to SOHO, from Compton to Hubble to Spitzer -- these deserve recognition as great probes, too.

Pears: Missions that provide a (for want of a better term) spiritual satisfaction deserve a special category. The first views of a full Earth, the oblique view of Copernicus from L.O. 2, the first views from the surfaces of the Moon and Mars, the view of backlit Saturn and its rings in all their glories -- these are views that nourish the human spirit's need to explore. Almost every good mission has provided this to one degree or another... but some more than others.

Strawberries: Almost every mission returns more data than the last one. As time and technology progress, each new spacecraft is more capable than the last, each can return more data than the last, each is more productive than the last. By this standard, the most outstanding mission flown is usually the most recent one accomplished. (Differences in scope between Flagship missions, Discovery missions, etc., notwithstanding, that is.)

Kumquats: There is something to be said for the inherent interest generated by the body or bodies being studied or probed. If you feel that icy moons are inherently more interesting than rocky bodies, then you're going to be interested in Voyager, Galileo and Cassini data more than in Viking or Luna data... now, in my mind, there is no such thing as an uninteresting Solar System body, so I tend to discount this category as being much of an overall criterion. But that's me.

So -- maybe we ought to be nominating missions in categories like the ones above, rather than in an overall "10 Best" kind of format...?

-the other Doug