A look back at a look forward, 1960 Options

[JRehling]

When I was a kid in the late 70s, a reality of the world around me was that books had a long shelf life. For my family's budget, used books were more affordable. My school and my library had the same situation. And in many cases, it made no difference. Shakespeare and trigonometry were the same in 1978 as they were in 1958 or 1878. In this context, one of the books I first learned about the solar system from was Alan E. Nourse's "Nine Planets." It was first written in 1960, before Mariner 2, and I probably first read it around the time of Viking and Voyager, although I can't put a pinpoint on the date.

I recently bought another copy of it from eBay and I'm fascinated by the look back in time. I still own original copies of other books from the early 70s, so the issues are similar, but Nourse's book is a bit more detailed than the others. Nourse was writing for adults. He was not a scientist, but a well-read amateur. I'd say the level of scholarship in his book is a notch below Scientific American, but not far below. He might be spinning the interpretations of things he reports, but he is not inventing much, if anything, from whole cloth.

I won't try to itemize all of the things i'm finding but I may turn that into some blog posts. What I find particularly interesting is when an incorrect "fact" is presented and seeing where the error slipped in. Of course, a lack of information is excusable. No one in 1960 had access to many facts about the solar system that we have now, and that's nobody's fault. What is interesting to me is when something flatly incorrect is presented as certain. And here is a partial list:

• Mercury's rotation is synchronous.
• Mercury has an atmosphere.
• Venus's rotation is relatively fast. (He doesn't try to pin it down but asserts a range much faster than the reality.)
• Venus has a lot of water.
• Carbon dioxide is not the main component of Venus' atmosphere.
• Mars really has the linear "canals" reported by Schiaparelli and Lowell.
• Mars has winter caps made of water ice.
• If Mars ever had life, then it almost certainly had intelligent life.
• Jupiter has a solid surface.

And, an assertion of another kind:

• Humans will certainly visit the planets relatively soon after the time Nourse is writing.

This is all a mixture of things believed by scientists at the time with Nourse playing referee in some cases to favor, vigorously, one side of a debate. And one may say, who cares what this one man, a non-scientist, thought? And I find myself caring because he, in turn, was the voice of this subject for so many readers. And this may say something about how science is communicated to us now.

I think, by and large, this particular field of science has learned from getting burned a few times and scientists are simply much more cautious now in ascribing uncertainty to their conjectures. Measurements are subject to calibration.

But it's interesting to track all of these things down as a detective story. For example, a mid-60s published paper on the rotation of Venus noted, based on radar, that the speed of Venus' rotation (the method in question could not detect direction) was in the range of 250 days, with large error bars. This is correct. Then the author noted that the significance was "obvious" as the range included the rotation speed that would mean that Venus rotated synchronously. The measurement was not incorrect, but the implication was! Yes, by coincidence (?) the rotation and revolution periods of Venus are within 10%, but they are decidedly unequal and since they are in opposite directions, Venus is most certainly not tidally locked.

What I find most interesting here is the use of these as a cautionary tale – how our incomplete knowledge should best be handled. We are about as ignorant now of, say, nearby exoplanets, as the world of 1960 was of the solar system. Or, to take things to a more critical example, of a new pandemic. What are the (understandable) missteps, like presuming that Venus's clouds must be water, or that a rotational period of about the same as a planet's orbital period is likely equal to that number, rather than a near miss?

I have a bit of non-astronomical interest in this, as well, as I have in my professional life worked with assembling question-answer pairs for students. And this puts us back in the shoes of philosophers who have long wondered, how can we know a thing?

[SulliedGoon]

I recall reading a book during childhood.
It was probably a 60's era book about the Moon.
It was full of Moon pictures wherein the author
used arrows to point to anomalous "structures" -
vehicle tracks, pyramids, tunnels etc.

Completely absurd and usually I could not see
whatever the author claimed he could see. It
was like a "Where's Waldo" book that is missing
"Waldo".

But, I still have fond memories of that book.
It is a time machine that takes one back to
a naive time when anything seemed possible.