Monday, October 03, 2016

Tsiolkovsky imagines the Earth seen from orbit in 1920

In 1920, the great Russian space visionary Konstantin Tsiolkovsky published Outside the Earth, in which Galileo, Newton, Franklin, Helmholtz, Ivanov and Laplace build a rocket. Along with a crew of 16 men, their colleagues elect Newton, Laplace, Franklin and Ivanov as first cosmonauts, while they stay behind in the Himalayan castle the scientists had built as a retreat from the world. 

It's a charming conceit, which Tsiolkovsky uses as a didactic device to explore all kinds of practical aspects of human spaceflight. What makes it especially interesting, from my perspective, is that he also creates a phenomenology of space through translating science into the experience of a human body. This is a theme which permeates his work, and he's rather brilliant at it.

In the passage below, he describes the Earth as it appears from orbit. I'll remark upon a few points of interest when you've finished reading it.

The Earth, taken from TIROS-1 in 1960.
Image courtesy of NASA
Men at the other portholes saw the Earth at a distance of a thousand kilometres. They didn't realise at first that they were looking at the terrestrial globe. But then they began to recognise the familiar contours of lakes and islands and continents amidst patches of clouds. It was like a huge, distorted map of a hemisphere. In actual hemisphere maps, the edges are clear and their scale is double that of the central portion. Here the reverse was true: the edges were reduced radially and very vague.
"...The edges are uneven and in some places they're jagged because of the mountain peaks. Something like a mist lies further in from the edges and there are many elongated grey spots - clouds darkened by the thick layer of the atmosphere. The spots stretch around the Earth's circumference. The further they are from the edges the lighter and broader they seem, and toward the centre they're rounded or irregular in shape, not stretched out".
"....Gentlemen," Newton said, "our rocket is circling the Earth once every 100 minutes. The solar day lasts 67 minutes, and the night, 33 minutes. In 40 or 50 minutes we shall enter the Earth's shadow. the Sun will set almost instantaneously. We'll hardly see the moonlit Earth, but its edges will shine brightly with all the colours of the dawn. This light will be our substitute for moonlight.
I'm warning you in advance what to expect to prepare people whose nerves are not strong..."
Meanwhile the Earth continued to wane and at the terminator the oblique shadows of mountains and elevations grew longer and longer. The impression was as if the stars were falling to the jagged sunlit edges of the Earth in tens, hundreds and thousands, so large was the portion of the sky occupied by the Earth and so great was the number of stars that could be seen in the void....they could see cities, large villages, rivers more than 100 metres wide. Sometimes the land below assumed one colour, as if covered with snow, and it was difficult to see anything....
The sky was so tightly packed with stars that there was hardly an empty space left: a black sky powdered with silver stardust, with the exception of the so-called coal-sacks, which were as black and empty as viewed from the Earth.
Binary, ternary, multiple and vari-coloured stars could be seen everywhere. The moment of eclipse, or night, was approaching.

It takes a little while for the rocket crew to realise that they are even looking at the Earth. Tsiolkovsky notes the difference from the world as portrayed in maps, which are always projections which have to be distorted in various ways to accommodate the globe to two dimensions. To these cosmonauts, it is the world which seems distorted rather than the more familiar map projections.

For us, in nearly 2020, the image of the blue Earth is so entrenched in our collective consciousness that it comes as surprise to see this feature absent from Tsiolkovsky's vision. However, right up until the 1960s, many depictions of the Earth from the outside were in grey tones. Even when Major Tony Nelson and Jeannie went into space, the Earth was greyscale. This was partially because many of the images from early human spaceflights and satellites, like TIROS 1, were taken with black-and-white film.

Tsiolkovsky argued that the atmosphere made the sky appear blue when on Earth, and outside the atmosphere, this effect was removed. Nonetheless, the Earth is in fact blue when seen from space, because of the oceans. This was something that he didn't predict, for all his feats of imagination.

From Tsiolkovsky's Album of Space Travel, 1933.
Image courtesy of the Russian Academy of Science

At a distance of 1000 km, especially in the 1920s, it is unlikely that our fictional cosmonauts would have seen many signs of human occupation. Large cities, perhaps, but probably not large villages. In 1962, Yuri Gagarin orbited at around 200 km. In a speech given after his return, he said that "Clearly distinctive are large mountain ranges, large rivers, large forest areas, shorelines and islands".  No Great Walls of China!

Newton issues a warning that the sight of the Earth passing into the shadow of night might be a bit much for some. I'm reminded of Asimov's classic story Nightfall (1941), in which the sight of the stars in the first black night for two thousand years causes madness. And indeed viewing this unfamiliar hyperobject does have its effects:

The men were stunned by the sight, some felt exhausted and moved away from the portholes. Other, alarmed by their cries, hesitated to look out. Many flew away to their cabins, drew the shutters, and lit dim electric lights. Others, however, darted excitedly from porthole to porthole with cries of surprise and delight.

I think this is what I like most about Tsiolkovsky's vision, that he takes into account the emotions, and allows for different reactions to this extraordinary experience. And there's no 'Overview Effect'. I have a healthy skepticism about the presumed universal experience of the Overview Effect - the feeling, described by so many astronauts when they go into orbit, of deep connection to a fragile world where humanity is united. There is no doubt something significant here, but the trope is so strong that you rarely hear dissenting views, such as those of African-American astronaut Mae Jemison. Astronauts are such a narrow and elite class; as diversity in their ranks grows, there will no doubt be more diverse reactions to the overview.

Finally, I note that our intrepid scientists and their crew do not appear on the rather wonderful Wikipedia list of fictional astronauts, for which they meet all the criteria. I might have to do something about this!

Tsiolkovsky, K. 1920 [nd] Outside the Earth. In V. Dutt (ed) The Call of the Cosmos, pp 161-332. Moscow: Foreign Languages Publishing House