Committee member Geoff Saunders has just finished a ‘massive open online course’ (MOOC) on the mechanics of space travel. Here’s his report
Yes, rocket science is hard… but very rewarding! When I saw a MOOC entitled ‘Space Mission Design and Operations’ I was hooked. Having worked for the European Space Agency (ESA), albeit in a non-technical role, this seemed too good to miss. The course was offered by Ecole Polytechnique Fédérale de Lausanne through the edX MOOC portal (www.edx.org).
It was hosted by Claude Nicollier, one of the first ESA astronauts, a veteran of four Shuttle flights, 1,000 hours in space and a spacewalk of eight hours to service the Hubble space telescope.
So what did the course cover? Not exactly Dan Dare’s dreams of extragalactic travels, but the down-to-earth science of leaving the earth! Claude started with a review of basic mechanics as applied to space, Newton’s Laws of Motion and Gravity in particular. It might come as a surprise that even after 350-plus years Newton’s work is accurate enough for all our space flight requirements. But if you are foxed by equations, these are hard enough to grasp. Remember it is rocket science!
Building on this foundation, Claude took us further into celestial mechanics. Kepler formulated our basic understanding of planetary motion even before Newton’s time, based on very careful observation. His laws, too, are just as good now.
Having revised the basics, we moved on to look at various orbits, around the earth, the planets and the sun. And the mechanics required to move between these bodies. Frequently manoeuvres require very precise adjustments to link up spacecraft, for example visiting the International Space Station.
Interplanetary travel opens another series of problems and opportunities for our spacecraft and robotic explorers. For example, space is very cold and the sun’s energy insufficient beyond a certain point. Calculating the energy requirements to move beyond earth orbit lead us to explore the ‘slingshot’ manoeuvres used by spacecraft to pick up the necessary energy for visits to the outer solar system, as with the recent Rosetta comet chaser and the New Horizons visit to Pluto. Whether interplanetary human spaceflight ever happens is another question altogether.
Of course, human spaceflight does catch the imagination. Mostly we can remember where we were when men first walked on the moon. If, looking back, that feat seems something of a pinnacle of achievement, that’s because it was. We have not ventured beyond low earth orbit since 1972.
There are plans in place to return to the moon and to visit near-earth asteroids within the next decade or so, and the course looked at the hardware currently under development to achieve this.
However, we have continued to explore the solar system with robots, returning amazing pictures of Saturn and its rings, Jupiter’s icy moons and fantastic details of the surface of Mars (take a look at Google Mars). We have huge amounts of information available to be studied here on earth, helping us understand the fantastic worlds our space missions visit.
Soon ESA will launch another Martian explorer, ExoMars, whose mission is to pave the way for a lander being built in Stevenage that’s designed to hunt for traces of life. It’s fantastic work; it’s hard; it’s rocket science!