Growing crops in space

You are writing space-based Science Fiction, and have decided your world is going to have a self-sufficient space station, base or space ship. A lot of Science Fiction books have this assumption in common. Any human colony, whether on a moving vessel, space station or on the surface of a…

Continue reading

Terraforming Mars or Venus?

In an earlier post, I described the difficulty a small planet, like Mars, faces when people are trying to terraform it: the planet simply doesn’t have enough gravity to hang onto the gases we need to survive. Some people suggested that maybe instead of Mars, we might look at Venus,…

Continue reading

How is the size of a planet related to its atmosphere

People have asked me to write something about terraforming Mars, a subject that is of great interest to Science Fiction buffs. I think Kim Stanley Robinson in his Mars series does a pretty good summary of all the currently-held scientific opinions on techniques of how we could achieve this. Yes,…

Continue reading

What if the Earth had no moon (part 2)

In a previous post, I mused about what the earth would be like with no moon. You may hear the Moon blamed for things as diverse as reproductive cycles and people’s moods, but in that post, I argued that if all of a sudden, we’d find ourselves without a moon,…

Continue reading

Once more on the search for exoplanets, and Alpha Centauri

This morning I came across this very interesting article on the Centauri Dreams website. By the way, Centauri Dreams, the website of the Tau Zero Foundation, is a very rich source for writers of realistic SF, especially in relation to planetary exploration and interstellar travel. The article summarises results and…

Continue reading

Communication in space

Electromagnetic waves, whether gamma ray, microwave, radio or visible light frequencies, travel through vacuum at the speed of—well, uhm—light. When on Earth, this means communication is pretty much instant. If the distance travelled in one second by a photon, a light particle, were a string, it would wrap around the…

Continue reading

What would earth be like without the Moon?

The search for terrestrial extrasolar planets in the habitable zone of stars suggests that these planets may not be all that rare. However, examination of the solar system points to the fact that planets with a satellite similar to the Moon are probably a lot less common. It is massive…

Continue reading

Why should we colonise space?

A post based on my recent reading of some of these books. That is, of course, a very good question. It seems that at the moment no one has a satisfactory answer. Space travel is expensive, it’s risky, only few people appear to benefit directly, for a questionable gain, and…

Continue reading

Exoplanets: could Alpha Centauri have any?

My fiction recently gave me cause to examine interstellar travel. Many writers tend to shy away from the reality that we’re a long way from anywhere. It’s too hard, too intimidating, too depressing. I, too, have done the wormhole thing, you know, where your characters can zip between worlds, but…

Continue reading

what makes a habitable planet?

Red dwarf and planet. Image pilfered from the Hubble Space telescope site, a great source of space pictures, all of which are free to use. Last week, scientists analysing data obtained by the Keck ‘planethunting’ observatory (located at the summit of Mauna Kea, Hawaii) revealed data about the GJ 581…

Continue reading