Published on 03 December 2010
Hello hello. Back after a long hiatus. So let's get started.
The movie Predators is based on the movie Predator that came out in . Since then there have been at least three tangents/sequels and three video games that I am aware of. The new Predators movie extends concepts from the first movie and even refers to events of the first movie. In this new movie, a group of human beings find themselves being hunted by a group of aliens. Hence the title "Predators". You know what probably happens in the movie right? The movie is nicely shot with some gorgeous scenery. Some of the actors are not very convincing in their roles. There are a few special effects but mostly the story relies on the thrill of the hunt to keep the viewers hooked.
We as usual are more interested in the science/technology/philosophy of space adventures. A word of caution: a few plot details will be revealed henceforth so people who don't want spoilers, please watch the movie and come back. We promise we will be here when you do :-)
One of the first things that struck me was the fact that in this movie and in several others like Star Wars, Star Trek etc., it is shown that even a small spacecraft is able to land and take off from a planet. Additionally, it is able to sometimes travel halfway across a galaxy. On Earth, with current technology, this looks very infeasible. Consider the landing part. The Apollo spacecrafts had very little control on the speed and their destination when they re-entered into Earth's atmosphere. Essentially, they just fell and only when they reached near the surface were some chutes deployed. It was not even clear where they would land until they were quite close to Earth. The NASA space shuttles do a much better job in landing but they have never travelled too far (except in the movie Armageddon). Now consider take off. Any class X student in India can tell you that to escape Earth's gravity, you require incredible amounts of energy. In fact, that's the reason for those huge booster rockets you find even when the shuttles take off to the International Space Station. Once burned, the boosters just fall off. So, how would take offs happen for spacecrafts like those shown in the movie. Last but certainly not the least, energy for space travel. If you want to travel at close to light speeds and frequently land and take off from planets, an incredible amount of energy is necessary. Where would this energy come from for small spacecrafts? Where would it get stored? Would it burn fast enough for spacecrafts to manouver, land and take off? These are all questions sidestepped in a movie but needs to be addressed by space scientists and engineers. One possibility for so much energy is nuclear fusion which is far from ready as of today. Another possibility is the discovery of some new fuel. Another is to find a way to neutralize gravity or generate it so that descents and ascents can be carefully controlled. So many problems before we can get there, no? Physicists, electrial, mechanical, computer and chemical engineers will have to work together before we can crack this one.
An interesting characteristic of the aliens is that they are not able to see in human visible range of light and instead track the group of humans using heat signatures and the like. This technology is in use today my people in the military and by disaster rescue workers. What is interesting though is the nature of the planets and people on such planets where the usable range of wavelengths is quite different from ours. For example, can there be a planet where there is abundant flora and fauna but very low levels of light? Why not? After all, in our very oceans, just after a few hundred feet, it is close to absolute darkness and yet, the ocean is teeming with life at these depths. The only reason life is less likely to be found at even greater depths is because of the extreme cold. Which brings us to the question on how do we evaluate planets for exploration? Even on Earth, there are insects which live less than a day. How can we identify sentient creatures if they for example, evolve over several thousand years? We cannot assume that planets with life may have similar forms as us or have evolved as us or even live like us. Biologists need to assist future astronauts in such areas. There is considerable work being done for classifying/cataloging life on Earth but the next step is to do that for extra-terrestrial environments as well.
Going in the same vein, we note that there are a tremendous amount of knowledge that is needed to avoid putting astronauts in dangerous situtations. It is therefore necessary to build electronics and instruments and probes that can remotely study, classify, catalogue and disseminate information about different possibilities. It is here that people from all areas of science have to come together---biologists, chemists, engineers, physicists, mathematicians, programmers and everyone who can have a bearing. So all of us spacehounds out there, if you are in an area of science, buckle up. You may be helping future astronauts with your work.