In 1965, Clarke, Asimov, and other science writers were at NASA watching the first images appear. "Craters. Duh, it's right next to the asteroid belt, of course it has craters. Not that any of us thought of it beforehand..."
In 1965, Clarke, Asimov, and other science writers were at NASA watching the first images appear. "Craters. Duh, it's right next to the asteroid belt, of course it has craters. Not that any of us thought of it beforehand..."
Do you have a reference for that account? I hadn't heard it before, and it doesn't sounds quite right.
They certainly knew the Earth and Moon had craters, so proximity to the asteroid belt isn't required.
I suspect they thought the atmosphere on Mars was thicker and like Earth, where the high rate of erosion erases evidence.
Digging around through archive.org I found https://archive.org/details/sim_popular-astronomy_1944-05_52... from Popular Astronomy 1944
> The following extracts are taken from pp. 49 and 50:
> “The recent dominance of the meteoritic impact theory of crater origin makes timely a review of the oases-crater question of Mars. In this treatise, these conclusions have been pointed out:
> “I, Meteorite craters are known on the Earth and Moon; therefore, craters exist on Mars.
> “2. The circular oases on Mars are the size, shape, and number of comparable lunar craters.
> “3. Crater depressions form a natural reservoir, accounting for the intense vegetation in the Martian oases,
> “4. The random distribution of crater oases is apparent, indicating that the canal system was adapted to this haphazard arrangement.
The reviewer of the above points out
> “Why didn’t someone think of the crater theory sooner? The answer is simple. Someone did. Back in 1892, at Arequipa, Peru, W. H. Pickering not only discovered the small black spots on Mars, but he also recognized their similarity to the circlets on the Moon. Because lunar craters were then believed to be volcanic, Pickering may be forgiven for implying that the Martian craterets also were of volcanic origin.
We now know these crater oases were not real. My point is only that some people proposed meteoric craters on the Moon before the 1960s.
BTW, the SF of the pre-Mariner era does have volcanic craters on Mars, like https://archive.org/details/Amazing_Stories_v15n01_1941-01_c... and https://archive.org/details/Startling_Stories_v07n03_1942-05... .
I also found https://archive.org/details/exploringmars0000rich/page/150/m... saying in 1954 "no irregularities due to shadows have ever been observed along the terminator—the line dividing daylight from dark—such as would be produced by Martian craters." The author was an American astronomer and also a SF writer in the 1950s. By this we know astronomers were already considering there might be craters on Mars as there are on the Moon.