Astrobiology Q&A

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.


How likely do you think it is that life exists on other planets?
– Alex, 15
Well clearly as someone who has chosen astrobiology as my research career I think that the chances are good of discovering life beyond the Earth! The more we discover about the incredibly adaptability of life on Earth, and the environments suitable for life on other planets and moons, the more confidence we gain that biology may have emerged on other worlds too.


In your opinion, what is the most likely form that this life will take and why?
– Alex, 15
Microorganisms are by far the most diverse forms of life on Earth, and the extremophiles show us just how adaptable bacteria and archaea are to different extreme environments. Furthermore, for the vast majority of the history of life on Earth, it has been solely microbial, with complex multicellular animals and plants appearing in only the past half-billion years or so. For these reasons, if life does exist beyond the earth it will be mostly microbial.


In your opinion, where are we most likely to find life and why?
– Alex, 15
Within our own solar system, the planet Mars, and the moons Europa and Enceladus, are thought to be the most likely to have provided environmental conditions suitable for the emergence of life. We explore these near-by worlds with our space probes. But in recent years we have also been discovering more and more earth-like planets orbiting other suns in the galaxy. Perhaps our telescopes will discover signs of life on one of these exoplanets before we find evidence of past or present life within our own solar system,


What do you think is the most important research project(s) currently underway, that will help us to further investigate life on other planets?
– Alex, 15
Recently, astrobiology has been making huge progress in three main areas:
(1) Extremophiles – we’re finding life on Earth surviving in incredibly inhospitable (to us!) environments, and understanding these limits to habitability, as well as the survival strategies used by extremophile organisms, teaches us about where life might be possible on other worlds
(2) Exploration – our space probes, such as the orbiters we’ve sent to the Jupiter and Saturn systems or the rovers we’ve landed on Mars, have been telling us enormous amounts about the environmental conditions found on other planets and moons in the solar system, and whether they could ever have supported life
(3) Exoplanets – in recent years we’ve been discovering more and more earth-like planets orbiting other suns in the galaxy. We may find that some of these exhibit signs of life that we can detect from far away with our telescopes – such as the presence of both oxygen and methane in their atmosphere.


    • lewis

      Hi Shruti, wonderful to see that you’re so interested in astrobiology at such a young age! You can get into astrobiology from any science background – biology, chemistry, geology, astronomy or physics – so keep working hard at school and then follow into whichever science interests you most for university.

  1. vanshikha

    I want to know the step to the career of astrobiology iam an indian student and m still in class12.pse enlist the step serially to this profession.

  2. Akshay Dhargawé

    Hi, I’m an Electronics Engineering student! And I really don’t want a job as an Engineer. I’m already in my Third year, and my parents are forcing me to complete my Engineering
    Well, any ways, I would like to know if it is possible for me to get into Astrobiology with my Engineering Degree?
    I’m really, truly interested in Research in this field, as I find myself reading more about this rather than my Engineering Syllabus
    Thank you!

  3. Tabetha

    Hello, i am a graduating student hoping to pursue astrobiology after my undergraduate degree. I am continuing to medical school afterwards and was wondering what steps i may have to take once i graduate to pursue astrobiology as a career, is there any degree, or study i must do before?

  4. cheshtaa

    Im an undergraduate student in microbiology, chemistry and zoology (India). I am interested in pursuing astrobiology. Is doing an MS in marine science or paleobiology helpful in this respect? If not, kindly suggest the sub topic.

    • lewis

      Hi Chestaa,
      Yes, microbiology and chemistry are both good ways in to astrobiology. Paleobiology is also useful, as many of the first signs of life on Earth and early evolution are fossilised bacteria in ancient rocks in places like Greenland and Australia

  5. Antonio Zizola, 20

    Hello sir,
    I’m currently a studying biomolecular science and technologies in Italy and I as I was studying biology I got interested in astrobiology and I wanted to know more. I was wondering if this course would be optimal to become one day an astrobiologist. Are there any master degrees useful for astrobiology or should I look for a Ph.D specific to the topic instead?

    • lewis

      Hi Antonio, yes absolutely – I got into astrobiology from a background in Biological Sciences! I don’t know of any dedicated astrobiology Masters courses, but universities do offer Masters in Planetary Sciences and you might be able to find one with a component of astrobiology. But a Masters is by no means required for a PhD, so you could simply try to find research groups that overlap with your interests and contact them directly to ask about PhD opportunities.

  6. Ainsley

    My name is Ainsley and I am an 8th grader in Colorado. I am seriously interested in astorobiology, and I was wondering what high school science classes would be most helpful. I am a straight-A student, if that does anything to affect the answer. Also, at the high school I will be attending, there are both AP (advanced placement) and IB (international baccalaureate). Do you know which of these classes would be more helpful towards college, and in the field of astrobiology? Thanks.

    • lewis

      Hi Ainsley,
      Astrobiology is a very interdisciplinary field, so it doesn’t matter a great deal what sciences you take at high school: biology, chemistry, physics, maths would all be helpful. And it doesn’t matter if you take the Ap or IB syllabus either. When you get to college, you can start focussing on whichever science you find most interesting, and you might even be lucky to find that your college offers a short module in astrobiology as part of the degree. But even if not, you’ll still be able to get into astrobiology (I didn’t move into astrobiology until after my degree in Biology)

  7. Justyna

    Hi. I am in year 12 in the UK (17 years old). My dream is to be an astrobiologist. I’m taking Biology, Chemistry, Physics, Maths and Art (but that one isn’t relevant) as my A-levels, and I am loving every second of every subject so, so much. I’ve been in love with science ever since I was two or three years old, and I just can’t get enough of books by known scientists (I’m a bit obsessed with Richard Dawkins), as well as documentaries, articles, and anything I can learn from.

    The thing is that we really can’t afford university, and my parents say that they refuse to try and get the money unless I tell them EXACTLY what job I want to do after university. Every time I mention scientific research as a career, they laugh at me and say that barely anyone in the world does that and there is no way that I can, and that it’s not a job. They also say that I will never get a PhD because nobody will pay for it and I’ll end up homeless. It’s absolutely useless trying to argue with them and I feel sick every time they bring it up.

    I have until the end of next week to tell them exactly what I’m going to be doing in over five years’ time. So my question is: other than research and teaching, what can I do as a ‘real job’ in the field of astrobiology? The more realistic the better. After that I will do everything I can to prove them wrong.


    • lewis

      Hi Justyna, I can understand that your parent’s love means they want the best for you in life, and to have a good career. There certainly are lots of scientists in the UK, and after a degree in one of the STEM subjects at university you could get a well-paid job in industry — working in a pharmaceutical company or for an engineering firm, for example. Research in astrobiology is just one small part of the possibilities, and if you get a job elsewhere you can always feed your passion for the subject by keeping up to date by reading or watching documentaries.

  8. Imogen

    I am in year 11 UK and currently in the process of choosing my a levels. I have so far chosen biology as I love it, Spanish because I enjoy learning a new language, chemistry which I don’t enjoy as much but I have chosen it to keep my options open in terms of a medical career, and maths as my fourth option. I have always been interested in the universe and life, and when I discovered astrobiology I thought it’d be perfect an biology is my favourite science. By the way, I’m more interested in the research part of astrobiology. I am predicted A* grades for all my sciences. My question is: to what extent is physics required for astrobiology and would I gain a disadvantage for not taking it?

    • lewis

      Hi Imogen, sounds like you’ve chosen a very sensible set of A-level topics, and for very good reasons too! Although I took Physics A-level myself, alongside Biology which I then continued to degree, I know plenty of astrobiologists who didn’t. If you decide down the line that you want to, you can certainly get into astrobiology from the microbiology/biochemistry side of things, and you wouldn’t be held back at all without physics. L

  9. Cristian Ramírez Rodríguez

    Hi Lewis, I’m a second year student at Malaga University in Spain studying a biology degree. Since I was 12 I felt passionate about space and I decided I wanted to dedicate my life to learn about it. My first choice was to become an astrophysicist but then I realized that what I really was interested on was in development of life and the possibillity of life elsewhere far from Earth…

    This way I discovered my dream was to study astrobiology. This fact motivated me to get very high results during my school and high school years (I even completed curses like the one you suggested organized by Coursera page and University of Edimburg whith a mark of 96%) but then when I entered the biology degree in order to continue my way to become an astrobiologist my marks came down…I’m at second year and my average mark is only 6/10. As I know very high marks are needed if I want to get grants to continue my studies in this amazing science…Do you honestly think I still have chances to do it?? Or maybe it’s time to give up this dream and try to find another motivation in my life? Thanks

    • lewis

      Hi Cristian, congratulations on your Coursera mark! As with anything in life, if something’s worth doing it will probably be hard work, but absolutely worth the effort in the end. I struggled through parts of my biology degree as well, but am so glad now that I pulled my way through it, with the help and support of friends and family of course. But don’t be surprised if you’re finding university harder than school — that’s the way things progress, and everyone finds it the same. Good luck with your studies!

  10. Link Valley

    I’m studying general biology the university of Stirling and to be honest, I’m not sure if I’m on the right track. am I studying the correct the correct subject to have a career in astrobiology, or do I need to specialize in something specific?

  11. Rebekah Link

    Hi Lewis,

    First, id like to say thank so much for this website! It’s very informative, and I plan to take a look at the sites and courses you mention.

    I am currently taking general classes for my AS degree at a community college. I figure I will learn which subject I’m most passionate about once I get to a university for my bachelors.

    To my question.. are there any jobs that I could look into while I am going through school that would be related in any way to astrobiology? I don’t have any experience, but I would love to find something that could provide a gateway and learning opportunities in the field.

    • lewis

      Hi Rebekah, you’re more than welcome – glad the article was useful! If you were keen on gaining relevant experience whilst still at school you could look into the possibility of internships in your near-by university in labs that do microbiology or geology.

  12. Shantanu

    Sir I m confused regarding my future at 14 years age whether I do engineering or astrobiology. Kindly help me with it I love reading about other planets life and discovering things. Please help me.

    • lewis

      Hi Shantanu, at school I think the best advise is to continue with which ever of the sciences you find most interesting and our good at. As the article explains, you can get into astrobiology after university from pretty much any science background.

    • Karla Martinez

      U can take any I think. He said you can easily get into Astrobiology from any science background.

  13. Karla Martinez

    I am 13 years and I wanted to know if your high school matters? Is there certain ones you need to got to? I also wondered the same about college and university? Are there certain ones you need to take ?

    • lewis

      Hi Karla, I think it’s much more important that you work hard at school and get the best grades that you can, rather than the name of the school you went to! When it comes to choosing which university to apply to, some universities offer better courses in particular subjects, or have a better reputation for the quality of teaching they provide, and so that would be the sort of thing to consider at a later stage

  14. Jehad

    Dear Lewis Dartnell,

    I’m an italian recent graduate biology student in the University of Milano-Bicocca who has done a dissertation about EXPOSE-R IBMP and earned a certificate of Astrobiology and the Search for Extraterrestrial Life taught by Charles Cockell on Coursera.
    Now I’m looking for an intern position in astrobiology research.
    Could you give me some advice to find and apply for an astrobiology internship abroad please?
    I’m also undecided in which continent it’s better to do an internship for my early career: US or EU?

    I’m looking forward to hearing from you soon.
    Thanks for your attention.

    • lewis

      I think you can find equally good opportunities in either the EU or US. But I’m afraid I can’t advise you on internships around the world. You would need to do your own research into astrobiology groups that are involved in research that you are interested in, and then contact them directly to enquire about possibilities.

  15. Sudhakar T

    can student done BS research programme in Biology(india)is elligible to
    pursue astrobiology

      • rajalakshmi

        subsequently to become astronaut won’t it help? i want to become astronaut i am not interested in maths what to do after the Bsc Biology in India to become astronaut.

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