Has anyone noticed that tomorrow will be exactly 40 years since Mariner 4
flew by Mars? How time flies when you're having fun. (And how little we've
actually explored that planet since then, compared to what we thought in
1965 that we would have done by now. Of course, about 15 years of the delay
was due to the Shuttle.)

Thank you for the reminder, Bruce. I wonder if NASA/JPL will put out a news note on the anniversary? They did for Mariner 2's anniversary.

It still gets me when you look at Mariner 4's image path how it missed so many of the things on the Red Planet that probably would have made a difference in where we are with Mars exploration now had the probe imaged them 40 years ago tomorrow.

What really gets me is that Mariners 6 and 7 ALSO managed to miss all the interesting stuff, by pure bad luck. Thank God for orbiters. (Consider, also, that NASA's first plan for Mariners 8 and 9 involved having them carry out still another two Mars flybys, while dropping off impact probes to provide data on the atmosphere most of which could have been provided by remote instruments. Fortunately, Congress nixed that idea and NASA then switched to Mars orbiters.)

By the way, the unfortunate Mariner 8 joins Mariner 5 as the only actual reuse of one of those backup spacecraft NASA used to build for its Solar System missions -- the backups for Mariner 10, the Voyagers and the Viking Landers all reside in melancholy glory at the Air and Space Museum, despite the fact that NASA seriously considered trying to reuse all of them. (I don't know where the backups for Mariners 1 and 2, the Viking Orbiters and the Jupiter Pioneers are located, nor do I know if there even was a backup for the Venus Pioneers.) I was surprised to learn recently that NASA seriously considered cancelling Mariner 7's mission in 1969 so that they could reuse it as the second of the 1971 Mars orbiters.

I've noticed that even as a little kid.

Somtimes I get goose bumps thinking what if Mariner 4 imaged the vallys right off the bat!

The headlines could have read something like this .... "Cannels on Mars!"

Although the early US Mariners suffered 'bad luck' in terms of targetting, we should be pleased that they did as well as they did - if they had fared as poorly as the Soviet Union's craft (and let's be honest, there was a certain amount of good and bad luck on both sides) then I doubt if we'd have seen any of the later triumphs of interplanetary exploration, it being the accepted wisdom that it just wasn't doable. No, the early Mariners were triumphs, first, last and always!

Mariner-Mars 1964 Final Project Report online here:

http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1968009274.pdf

Thanks for pointing this out Bruce ... I have written an article on it, if You're interested I could send it to You in.pdf format
PhilCo126@yahoo.co.uk