Here are just a few of the questions I’ve received from people interested in astrobiology and the search for life beyond the Earth. If you would like to know how to get involved in this sort of science, see How to become an astrobiologist.
[For my popular science book on astrobiology, Life in the Universe: A Beginner’s Guide click here.]
[For The Knowledge: How to Rebuild our World from Scratch click here]
Could there be another Earth-like world with dinosaurs still on it?
– Cody, 18
Well, it depends on what you mean by how dinosaur-like. The best opportunity for life to evolve beyond hardy microorganisms into multicellular, land-dwelling animals we think would be offered by another planet like the Earth. Such a world would have a protective atmosphere, warm oceans of liquid water, continents and plate tectonics, and a climate that has been stable for billions of years. We think there is a good chance of many such planets in our galaxy, and so there may well be alien animals out there. And some of these animals could well share many of the features of dinosaurs – using eyes to sense the world around them, be cold-blooded, wield sharp teeth and claws as predators or self-defense as prey, or lay eggs rather than giving birth to live young like us mammals. So in this sense, you could describe life on this planet as being ‘dinosaur-like’. The frustrating thing, though, is that even if such a world existed in our own galaxy, it would be light-years and light-years away, and so we’d never be able to visit it in yours or my lifetime!
Does Astrogeology exist as a subject?
– George, 16
Yes, ‘astrogeology’ is absolutely a real thing! Although, the field is actually called a slightly different name – ‘planetary science’. Planetary science is all about taking what we know of the geology of rocks on Earth, as well as processes that shape the landscape such as volcanism, glaciation, river erosion, sedimentation, cratering, and so on, and applying this knowledge to other planets and moons in the solar system to try to understand how they have evolved over their history. For example, one of my friends focuses on the ancient signs left behind by water on Mars, and another on the cracks and fissures in the icy face of Europa. We even have pieces of other worlds delivered to the Earth – such as Moon rocks retrieved by the Apollo astronauts, or even bits of Mars brought naturally to us as meteorites – and planetary scientists study these closely to understand the minerals and chemistry inside and so how they formed. If you want to work in this area many universities have degrees in geology, and some offer geology with planetary science. Check on the UCAS system what A-levels you need – physics, chemistry and maths would certainly all be helpful (geology won’t necessarily be required as not all schools offer it). After you graduate you can specialise with a Masters course in planetary science or perhaps step straight to a PhD researching in the field and applying your knowledge to exploring other worlds.
Could aliens use materials from their planet to build a spaceship to Earth? And since aliens are accustomed to their planet’s environment, would they find it difficult to survive in Earth’s atmosphere?
– Taner, 16
Sure, planets and moons are all made from the same basic stuff – the same elements in their rocks, oceans and atmospheres. So if we can mine metals on Earth, you’d be able to do the same on other planets and build technology like radio transmitters or spaceships. As to whether a space-faring alien could survive on Earth without keeping his or her (or whatever sexes aliens have!) spacesuit on, it depends on how similar their planet’s environment is. Virtually all animal and plant life on Earth relies on oxygen in the atmosphere, as aerobic respiration releases lots of energy from food molecules to support our complex cells (whereas many microbes can live without oxygen, and some are even poisoned by it). So there’s good reason to expect that complex alien life would also need oxygen, and so would be sustained by a deep lungful of Earth’s air just like us.
Do you believe that alien sightings, such as the Roswell Incident and the Yeni Kent Compound UFO report, are true or that the people were simply imagining the UFOs?
– Taner, 16
There have been lots of UFO reports around the world, and although some are clearly hoaxes I also think that lots of the reports are honest and are from people who genuinely believe they saw something strange. I just don’t believe that a few strange sightings are good enough evidence to accept that alien spacecraft are visiting the Earth – although I would of course love to be proved wrong! It always strikes me as curious that UFO sightings are only by a few people at a time, and that something obviously technological has never appeared over any of the world’s cities and been seen by hundreds of thousands of people at the same time, and been captured as good-quality footage on video cameras or camera phones.
Where does your money come from to fund your research?
– Bryony, 16
Generally, money for scientific research in the UK comes from one of the national ‘research councils’ that are funded by the government, and so ultimately most of the research in the UK is paid for by everyone’s taxes. Each research council has a particular focus – engineering, biology, physics and astronomy, and so on. My own research funding comes from the UK Space Agency
What have you found to be the best piece of evidence that points to the possibility that aliens exist?
– Faaz, 11
Astrobiology is a very ‘interdisciplinary’ subject, meaning that it involves knowledge from lots of different sciences. There have been recent advances in three main areas that gives us astrobiogists confidence that there may be life beyond our planet. The first area is a whole category of organisms on Earth known as ‘extremophiles’, living in extremely hostile environments like the freezing cold, or very dry, or acidic. These extremophiles could survive the conditions found on other planets and moons. The second advance has been our exploration of the solar system with robotic probes – we’ve discovered that Mars, or Europa, or Enceladus could offer an environment suitable for hardy organisms (like extremophiles) to survive in. And the third area has been the discovery of planets orbiting other stars in the galaxy, known as exoplanets. We believe that there could be scores of Earth-like planets in our Milky Way galaxy, and so hopefully places with the best possible chance for life to develop.