I am an astrobiologist, sci-fi geek, and professor of everything groovy. I write about science, culture, math, history, space, and science fiction. Perhaps like you, I'm seeking a greater understanding of the nature of life and asking myself why all of this really matters. Come with me, and we'll ask some questions together.
I’ve recently agreed to become a co-host of the show Ask an Astrobiologist! Ask an Astrobiologist, brought to you from the community of SAGANet, is a NASA Astrobiology-sponsored show that airs online once each month. In each episode, either myself or Sanjoy Som will interview a guest astrobiologist to ask about their career paths, their scientific research, and the things that drive them to wonder about the nature of life in the universe. Every episode also features a photo contest with the potential to win some NASA swag! Ask an Astrobiologist airs live on SAGANet and on the NASA Astrobiology Facebook page. People watching the show live can ask questions of our interviewees on either streaming platform or on Twitter using #AskAstrobio. I’m definitely excited for becoming more involved with the show! Look for more here in the future, including episodes and my personal comments about what it's like to host a show like this!
I'm now finishing out 6 years of graduate studies at the University of Colorado Boulder. Yikes! Where did all of that time go? Those who know me also certainly know that this past year has been exceptionally rough. Long hours of typing, physical and mental self-abuse, and a slowly degrading attitude toward everything is what comes out of writing a PhD dissertation. Well, that and the fact that you then get to defend that work against a group of research scientists. After writing over 77,372 words in 299 double-spaced pages with abundant figures and tables, all the while using cigarettes, coffee, and booze to fuel the ever longer days of writing (for most of 2017 I was working 60-100 hours a week on the writing), I then had to parse it all down into one coherent talk for my public defense (which comes before the actual defending occurs). In the week leading up to the talk, I was having some hard times. I was aiming for a 40-45 minute talk, but also knew that I had to have enough data to get the main points across while also making it accessible to a general scientifically-literate audience (something I find to be extremely important). In my many practices, I either hit the right time but with not enough information, or I had lots of info and ran way over on time. Luckily, I was able to give a practice talk to a group of friends and they helped me hone down some key ideas and to figure out how to focus the talk more on my main contributions. Still, the night before my defense I did a run through of my talk and it hit 90 minutes. I was crushed. I was terrified. I was mortified. I tried to sleep that night and it just wasn't happening. I think I may have gotten a total of 45-60 minutes of sleep the night before my PhD defense. When the morning finally came around, I did one more practice run with my wife, and this time it hit 45 minutes and felt like just the right level of info for the general audience and for my committee (at least, according to me). I managed to walk away from it and have a breakfast out with Amanda. I then did a 30 minute meditation in the tub, using a guided meditation from The Honest Guys on Youtube (I definitely recommend this one. It's called The Sanctuary). I managed to get myself shined up all nice like and head in for my PhD defense. I'm so thankful for the huge turnout of people who came to the live talk. It was great to speak in front of a room full of such awesome people! Also, I was super lucky in that my friend Mike of the Don't Panic Adventure Club duo was able to attend and made a pretty snazzy recording of my talk so that I could share it here with you, on A Cosmobiologist's Dream. Check out the video below (or click here to go to the NASA Astrobiology Youtube page and watch it there):
If you watched the talk, I hope you stuck around until the end to see a picture of my husky, Darwin. He's a hipster, but he's one cool cat (or dog, or, whatever). Of course, after that talk came the actual PhD defense. The part where everyone else is kicked out of the room and it's just the lowly graduate student and their panel of research scientists (the committee) who will judge their work. I think I'll save the take-home points on my actual defense of my work and the comments from my committee until I finish the revisions of my dissertation (it may actually end up a little shorter by the end!). At that point, I'll post a link to the dissertation itself and give an overview of everything. Well, after the night-of-no-sleep and all of the fear and then the talk and the defense that followed, I was finally through the defense side of the PhD process. Although I successfully defended, there are a lot of revisions to do yet. However, maybe now I can cut back to more sensible hours (especially since a graduate student's pay has nothing to do with the amount of work they do). Also, in finishing up the defense, it was incredibly awesome to celebrate over whisky and champaign with so many awesome people. We later went out to The West End Tavern, one of my favorite places in Boulder for having a good whisky. I had several scotches and bourbons, including a 25 yr. Laphroaig and a 23 yr. Pappy Van Winkle (both remarkably awesome glasses of booze!). My friends, being the incredible folks that they are, covered the costs of the spirits, of which I'm pretty sure I drank over 400 years of aging that night. Now that I'm through the defense, I'm excited for working on the revisions and hopefully publishing at least one more paper from my work (though I think there could be two or three there as well). After all that I put myself through this past year, I kind of feel like Andy Dufresne in The Shawshank Redemption, after crawling through all of that mess of shit and grossness and finally feeling the beauty of the world as I find some freedom. It feels like I'm now able to discover myself again as I finish out this research and prepare for what comes next. As George Fairman's song goes, "I don't know where I'm going, but I'm on my way!"
Tim Robbins as Andy Dufresne in The Shawshank Redemption (1994)
The interwebs have taken on a mournful and yet celebratory tone today. David Bowie's death on this day, the 10th of January, 2016 C.E., in some ways is just now bringing the life and music of Bowie back into the spotlight for some people, while for others of us his work and his impact on music, on fashion, and on art have jut been deepened as we look back at the ways in which he impacted our lives. Certainly, I heard David Bowie's songs when I was a child (I was born in 1983 and had an artist for a father, after all). However, my first memory of David Bowie, much as is the case for many people my age, was in his role as Jareth, the Goblin King, in the film Labyrinth (1986). Who could forget how an articulate David Bowie introduced us to stylized androgynism, fashionable and well-spoken villains, and child film stars in tights with bulges?! The Labyrinth song Magic Dance remains one of my favorite songs from a Henson film:
Of course, the life and music of David Bowie has become pop culture history. Those of us interested in space exploration have almost certainly heard Space Oddity. Hell, astronaut Chris Hadfield went as far as to create a music video and cover version featuring Hadfield playing Space Oddity from the International Space Station:
There are a lot of great articles passing about today to honor the best songs of Bowie's career. From The Man Who Sold the World, to Changes, Rebel Rebel, and even to Heroes, Bowie created music that most certainly would be on the soundtrack for the later half of the 20th century C.E. Generations come and go, each of us adding our own little bits to history through our music and art, our culture and our science, our technology and our social movements. David Bowie's music will most certainly live on long from this day at the passing of his life. I think it must be an honor to leave this world knowing that you have impacted the lives of so many others (hopefully in good ways). Cheers, David Bowie, and thanks!
...but a lot of journalists have once again shown that they love to fall for quackery
This image of comet 67P/Churyumov-Gerasimenko was taken by the Rosetta spacecraft on 15 June 2015 (ESA/Rosetta/NAVCAM)
Earlier this month, The Guardian posted an article which started a brief but infuriating internet fire of gossip about the possibilities for life on comets. Specifically, the article announced that Max Wallis and Chandra Wickramasinghe had claimed during a talk at the Royal Astronomical Society'sNational Astronomy Meeting that the organic-rich crust of comet 67P/Churyumov-Gerasimenko is best explained by the presence of microorganisms. Indeed, Wickramasinghe (whom the author of the article titled as a "maverick astronomer and astrobiologist") was quoted as saying that their finding of life on the comet was "unequivocal". As an astrobiologist and a fan of ideas about the possibilities for alien life out there, I like to wonder about whether there could be living organisms on cometary material. Based on that, you might think I would have been excited about this "news", but a quick read into the announcement and where it came from (more importantly, who it came from) quickly suggests that these findings are a bunch of bunk. Chandra Wickramasinghe has become known in the astrobiology community as someone who has a conclusion that alien microbes are everywhere and who will stop at nothing to try to prove his belief. This makes him less of a "maverick astronomer and astrobiologist" and far more of a pseudoscientist and a threat to real science.
Taken from a page of Skeptical Raptor's blog, where it's shown that debunking quackery can be fun as well as rewarding
In this announcement of "finding" alien life, Wickramasinghe and Wallis take the findings of organic-rich materials on the surface of comet 67P by the Rosetta mission and make the claim that such materials are "not easily explained in terms of prebiotic chemistry". They went further and told their audience at the National Astronomy Meeting that they have conducted simulations which suggest that microorganisms with antifreeze proteins could explain dark, organic-rich features as well as certain icy structures on the comet. Wickramasinghe was quoted as saying "...data coming from the comet seems to unequivocally, in my opinion, point to micro-organisms being involved in the formation of the icy structures, the preponderance of aromatic hydrocarbons, and the very dark surface."
You should always be cautious in trusting someone who uses statements like "unequivocally" and "in my opinion" in the same sentence. As Chris Lee pointed out recently in an Ars Technica article titled "Magic carbon layer not a sign of extraterrestrial life", the finding of organic carbon on the surface of a comet is by no means surprising from the stance of modern surface chemistry. In fact, we now know that organic compounds are abundant in the universe. We've discovered organics in meteorites, on comets, on other worlds, and in interstellar space. It's no surprise that the Philae lander discovered organic material on comet 67P, but just because there is organic material there in no way implies that there is also life. Decades ago, it might have seemed that organic material automatically implies life, but we now know that the conclusion of life does not follow simply from the presence of organic material in a sample. Such thoughtful approaches to science, however, are not in Wickramasinghe's realm of thought. It seems that Wallis and Wickramasinghe have taken the approach of dressing up their hopeful belief as a scientific certainty.
This isn't the first time that Wickramasinghe has been involved in unjustified claims that alien has been discovered. Wickramasinghe has previously claimed that viruses like SARS, the bird flu, and the 1918 flu epidemic were extraterrestrial in origin. This pseudoscientist has also been involved in "publishing" claims of finding alien microbes in meteorites and in the atmosphere through the fake science source called the Journal of Cosmology. Phil Plait, author of the Bad Astronomy book and blog, has written several articles pointing out Wickramasinghe's fallacious claims. Phil even tackled this recent claim of life on 67P with his article "Life on a Comet? I’m Gonna Go With “No.”" Dan Evon also briefly covered this non-discovery of life in an article on Snopes. It gets tiring sometimes battling against the fraudulent and the quacks, and some people might even ask why we then do it. The answer is simple: in our age of abundant information, where disinformation and misinformation run rampant and many people are illiterate in science and technology, the frauds and the quacks pose a serious danger to the future of our civilization. If we lose the scientific method, if we allow ourselves to dwell in unjustified claims, and if we forego evidence for satisfaction, then it's only a matter of time before a new dark ages befalls us and we have to start all over again. It's not always easy to determine the differences between science and pseudoscience (indeed, philosophers of science have been trying to figure out how to do that for quite some time). Claims like those made by Wickramasinghe and his fellow pseudoscientists seem legitimate to many people, especially when news sources claim these people are "experts", "maverick astronomers", or "top astrobiologists". Yet people like Max Wallis and Chandra Wickramasinghe are a threat to modern science and to the public. Their approach of accepting their preformed conclusions without significant evidence or even rational skepticism is a bane to modern science. I sincerely hope that, moving forward, we will see more scientists taking to social media and more reporters seeking input from real scientists to fight the bunk of people like Wallis and Wickramasinghe when they start to peddle their snake oil. We may one day, perhaps very soon, discover evidence for extraterrestrial life. I've dreamt of that moment since I was a child. Many of us have. Yet jumping the gun with false assertions of alien life does nothing to improve our pursuits in astrobiology. Certainly, if and when we do find actual evidence for life outside of our biosphere, you will hear the news coming from far more reliable sources than Wallis and Wickramasinghe.
Earlier this year I came to a realization about myself: I was becoming too judgmental about where I was in life (or, at least, in the American ideal of what life is "supposed" to be), and I felt completely unfocused with regard to my daily life. I felt distracted by my perceived failures, and I was most assuredly mentally and emotionally depressed. So I decided to do something about it. In an attempt to regain a connection with myself, I took up daily mindfulness meditation. That decision has been personally rewarding and I've found myself more motivated, more relaxed, and just plain happier. I feel like I can better control my focus now, and I've been slowly building healthier thoughts about what I'm doing in my life. I'm by no means an expert on mindfulness meditation, but I thought I'd share a few of my thoughts as I begin my path to being more mindful about myself and my connection with other people and other parts of this life. Below are some of the things that I've done so far to begin my mindfulness meditation practice.
When I first started daily meditation, I wasn't really sure what to do. I grew up training in the martial arts and have tried to meditate many times before. I guess I was too quick, even now in my thirties, to try to force myself to "think about nothing". I think there's a very common misconception that meditation needs to be about completely clearing your mind. As an active thinker and a scientist, that's not something I've been very good at. I imagine most of everyone else is pretty much in that boat as well. It's hard to tell yourself to stop thinking. In fact, I think every time I tried to meditate when I was younger and I told myself "okay, now I'm meditating; stop thinking" it actually forced my mind to wonder even more. Each time I felt like I was losing control of my ability to stop my mind from wondering, I lost my focus on the meditation and would end the practice. There are a lot of articles online suggesting that this is one of the most common problems, if not the single most common problem, that a lot of people have with meditation (outside of any negative stereotypes some people might associate with meditation). Finding guided meditations has been the key for me to get started in mindfulness meditation. It's helpful to have someone else's guidance, to hear their voice, and to try following the paths they've already cleared. There are lots of tools out there, online and in print, that can help with guided mediations. My favorite so far, and the one that has helped me to really get into guided meditation, is called Headspace. Headspace is an online and mobile app that offers guided meditations as led by former Buddhist monk Andy Puddicombe, a person whom Ed Halliwell of The Guardian has said is "doing for meditation what someone like Jamie Oliver has done for food" (see this New York Times article for more). Here's a video from a popular TED talk that Puddicombe delivered where he introduces the idea of taking some time to be mindful:
If you check out the Headspace website, you'll see that you can sign up for free and even check out the first set of ten 10-minute meditations for free. Those first ten meditations were fantastic! Puddicombe's guidance is wonderful and the introduction to mindfulness is superb. Each of those ten meditations started with finding some awareness of the sounds in the local environment and the feelings in the body. A slow scan of the body was helpful in noticing how things were feeling, while Puddicombe pointed out not to dwell on trying to make something feel different (instead, just noticing how everything feels at that moment). Much of the time in those meditations dealt with focusing on the breath; being aware of the inhalation and exhalation and the process of breathing. Focusing on the process of breathing seemed to make it easier to focus my awareness on one key thing. Indeed, much of my work in mindfulness meditation so far has centered on this idea of focusing on my breathing.
Thoughts will come and thoughts will go... One of the best parts of the first ten meditations on Headspace is that Puddicombe helps the practitioner to realize that there are thoughts that are going to pop up in the mind, but the key is to let those thoughts go as soon as they come without judging yourself for the fact that the thoughts are there in the first place. I found this part to be the key to my awareness in my meditations. I had to consciously be aware of when thoughts would come into my mind and then let them move on without worrying about whether or not I'd come back to them. However, maybe more importantly, I had to stop judging myself for the presence of those thoughts in the first place. This process of having thoughts come and go might sound easy, but it's something that I've found to require lots of conscious work. Perhaps what makes this part of the Headspace meditations even better is that near the end of each of the first ten sessions, Puddicombe advises the practitioner to take a moment to let the mind wonder, to allow the mind to entertain those thoughts that come. It's like a brief moment of wonderment. The mind goes off and explores whatever thoughts might come and go. Interestingly, I feel like the thoughts that I entertain this way, after having spent some time focusing on one thing, are fuller and more beneficial thoughts. I've really enjoyed the free Headspace meditations. I would very much like to subscribe to Headspace, but the cost is a little more than I can currently afford. It's not very expensive (it can be as low as about $6 a month), but I really prefer not to have any more monthly charges in my life right now. Perhaps, depending on where my meditation practice takes me, I will look into subscribing in the future. However, for now, there are lots of free guided meditations out there for anyone who is interested!
Videos and Apps with Guided Meditations: After trying the Headspace meditations, I've been searching around for guided meditations that fit me and have found lots of good stuff. Here are some of my top suggestions for what's worked for me so far: The Honest Guys on Youtube - The Honest Guys have a collection of awesome videos with meditation music and/or guided meditations. I like their approach and have found their guidance very helpful. I highly recommend trying out some of their videos to see what you think. Here's a rather good one that focuses on relieving stress, if you would like to give it a try:
Jason Stephenson on Youtube - Jason Stephenson has also has a variety of guided meditations that have worked well with my practice. I've found so far that there are some guided meditations that just don't work for me, for various reasons. I've found so far that some of Stephenson's meditations didn't seem so easy to get into, while some of them have been smooth and have fit me very well. Here's a rather good one that is aimed at beginners but seems like it can be beneficial for anyone who seeks guided meditations:
Insight Timer, a mobile device app - Insight Timer is an app that you can download for a smartphone or other mobile device. The app offers a large variety of guided meditations (I've only completed the shorter offerings thus far, as my practice is still usually short in time). Insight Timer also offers a simple timer for meditation. The free version of the app has a simple bell that rings to start and end the timer, while there appears to be a paid version of the app that has more variety in the types of bells and numbers of rings. Stop, Breathe, & Think - There are of course other apps to try as well. I've recently started on called Stop, Breathe, & Think. Their guided meditations are available for mobile devices and they also have a web app. I've only just discovered their meditations, so I can't say much about them, but I like their app so far and I think I'll be using it more in the near future.
You can find this image and an article with 5 interesting techniques for meditating here
Moving Beyond the Guide I've really enjoyed guided meditations so far. They've helped me to overcome the barriers I've previously had to meditating and have made the experience very rewarding. I think that I'm now at the point of moving beyond the need for guided for all of my meditations. I've found myself enjoying meditating on my own, though I still like to have some peaceful music playing. I'm hoping to continue my mindfulness meditation practice, perhaps even eventually helping to guide others with the practices that I have found helpful. If you're interested in mindfulness meditation, then here are a few more things I've found that might interest you:
- The Chan Meditation Center has some interesting thoughts about how to meditate, and also offers this nice 8-form moving meditation - This article from Greatist has 10 ways to meditate, from Tai Chi and breathing meditation to dance and walking meditation - Here's an article for beginning meditation from Gaiam Life - Finally, this article has some interesting ideas for meditation for people who are really against the idea of sitting and meditating
Later this evening I'll be giving a public talk at Fiske Planetarium at the University of Colorado Boulder! I'm thoroughly stoked to give this talk. We're going to take a journey to some of the worlds in our solar system and also some worlds far beyond and ask ourselves about the types of life that could come to live in such places using the only examples of life that we have to work with, the life from our own world. During this talk, we will consider some of the craziest creatures on Earth and what they can teach us about the types of alien life that may exist out there. This talk is part of the Above & Beyond: Cosmic Conversations series, organized by my friend, Morgan Rehnberg (find him at Cosmic Chatter). These are public talks that are focused at creating conversations between speakers and the audience so that we can all share in the storied wonder of science, human history, and our place in the cosmos. The Craziest Creatures on Earth will hopefully inspire those of us in the theater at Fiske Planetarium to engage in lasting conversations about how crazy and beautiful life can be, and about whether or not we're alone in this vast universe. Here's a little overview of what we'll be talking about at Fiske Planetarium this Friday night:
A Multitude of Worlds
An artist's impression of what Kepler 22b might look like
Many of us have dreamed of alien worlds, wondering what planets orbiting other stars may be like. We've created alien life in our science fiction and we've imagined what a visit to an alien biosphere might be like. Over the last couple of decades, we have begun to discover only a fraction of the worlds that must exist in our universe. Yet the only life that we've ever known is life here on our Earth, our home. As our species continues to explore more of our solar system and to discover other planetary systems far away, it begins to feel like we are continually approaching a time when we might have an answer to the age-old question "Are we alone in the universe?" What might alien life be like if it exists? Would it be anything like the life we know here on Earth?
Life on Earth and the Oddness of the Hummingbird
Life as we know it has been on Earth for at least 3.5 billion years, but probably even much longer. Through that time, life has evolved to dynamically fit and fill nearly every ecosystem available on the the thin habitable shell and lower atmosphere of the planet. Since the diversification of multicellular lifeforms during the Avalon and Cambrian Explosions, over 500 millions years ago, plants, animals, and fungi have developed unique body plans and forms of locomotion to better gain energy, fight, reproduce, and live. Sometimes an evolutionary adaptation comes along that seems bizarre relative to how we live. Take for instance the hummingbird. Hummingbirds are among the smallest birds on the planet, weighing fractions of a pound. Indeed, the smallest known bird in our modern world is the Bee Hummingbird, which weighs less than a U.S. penny coin. Hummingbirds get their name from the humming or buzzing sound that their wings make when we listen to them flying. The hummingbirds's wings beat on average 50 times per second, but have been recorded as high as 200 times per second. They beat their wings so fast that they can fly up to 34 mph (54 km/h) and they can fly backwards and upside-down. But that's not the craziest thing about hummingbirds. The strangest thing about hummingbirds is that they have a ridiculously high metabolism. For their little body size, they have a massive caloric intake. Hummingbird's will eat between 3 and 8 calories each day in nectar. 3 to 8 calories sounds small relative to us, that's really only a couple of grapes worth of energy, but if we consider caloric intake vs. bodyweight, then we can see that hummingbirds eat 77 times more than us. This is the equivalent of a human eating about 155,000 calories each day. That's a bizarre caloric intake. It makes the hummingbird a crazy creature in my book.
This video discusses research on how hummingbirds maintain their metabolisms
Denny's Beer Barrel Pub in Clearfield, Pennsylvania makes some gigantic cheeseburgers. One of them, The Belly Buster, weighs just over 20 pounds and holds 25,000 calories worth in energy. If we had the caloric intake of a hummingbird, then we would need to eat 6 of these calorie-loaded burgers and then, on top of that, we would need to wash it down with 6 800-calorie milkshakes. And we would need to do this every single day. That seems bizarre relative to how we understand our place in the world. When we consider what crazy creatures like the hummingbird can teach us about the possibilities for alien life, we have to keep in mind that not all organisms function the same way and we may one day find that alien life is wholly bizarre to us. Maybe there are worlds out there where most organisms have hummingbird-level metabolisms. Maybe there are worlds where vision or hearing have never evolved. Perhaps our alien neighbors have forms of locomotion, sensory organs, and even body structures that are adapted to environments with only limited similarities to our world. To constrain such speculations about alien life, we can take a look at some of the unique environments in our solar system and consider whether Terran organisms could survive in such places.
Storybots jam vid about the planets of our solar system Venusian Planets: A Hunk, a Hunk of Burning Love
Venus is our sister planet. It's very similar to our Earth in size and overall composition and it even has clouds, but, unlike Earth, Venus is a world completely obscured by clouds. The thick, clouded atmosphere surrounds and blankets Venus. That's because Venus has the densest atmosphere of any of the terrestrial planets. However, if we strip away the cloud layer and take a look at the surface of Venus using radar imaging (from spacecraft as well as Earth-based instruments), we see a chaotic terrain on a geologically young surface. The surface of Venus is a marred desertscape of volcanoes and plains with ridges appearing as cracks. From orbital observations as well as from a few spacecraft that landed on the surface, we know that the surface pressure of Venus is 92 times greater than that of Earth at sea level. Not only that, but the surface temperature of Venus is a sweltering 863 degrees Fahrenheit (735 Kelvin)!
Currently, we know of no life that could survive in the high temperature and high pressure environment on the surface of Venus, yet there are organisms on our planet that have adapted to high temperatures. Take for instance the microorganisms living along the margins ofGrand Prismatic Spring in Yellowstone National Park, Wyoming, U.S.A.
The center of Grand Prismatic is a beautiful blue of burning hot water, reaching temperatures up to 190 degrees Fahrenheit. As the water approaches the edges of the spring, it cools to temperatures that can be survivable for certain types of organisms. The yellows, oranges, and greens at the edges of the pool are pigments within microbes that live in microbial films at the pool's edge. These organisms are considered extremophiles, as they've come to inhabit an environment that is extreme relative to us. We know of extremophiles that have come to life in many of the extreme environments of our planet: from places that are hot to places that are cold, places that are acidic or alkaline, and places that are super-salty or even very high in pressure. Extremophiles have become a target for astrobiologists when it comes to understanding how life may have come to live and to thrive in various environments.
"The Toughest Microorganism": In the Red
One of the most intriguing worlds in our solar system is our little neighbor, Mars, the 'Red Planet'. Mars has long held the fascination of scientists and the public. In the late 1800's, the astronomer Percival Lowell announced he had made observations of striations on Mars that he thought were canals built by an intelligent extraterrestrial species. Lowell's speculation led to H.G. Wells' story The War of the Worlds and, in many ways, launched the early era of alien science fiction. Mars has been our most visited neighbor. We've sent orbiters, landers, and rovers to the Red Planet to learn more about it's geology as well as the possibilities for it to once have had life or to perhaps even currently have life. Mars has a great volcanic mountain, Olympus Mons, which is almost 3 times taller than Mount Everest. Mars bears one of the largest canyons in the solar system, Valles Marineris, which is a distinguishing feature when Mars is viewed from far away. The Martian surface is a cold, dry, and dangerous place for most of life as we know it. The surface has an average temperature of around -80 degrees Fahrenheit and there's only around 200 parts per million water vapor in the atmosphere (the Earth's atmosphere has an average of about 10,000 parts per million water vapor). We've known for some time that the surface of Mars is bombarded by intense radiation, since Mars doesn't have the strong magnetic field or the atmosphere that Earth has to protect us from radiation. However, we've recently learned from the Radiation Assessment Detector (RAD) instrument on the Curiosity Rover that the surface of Mars has even more radiation than we had previously thought. The first astronauts that we send to Mars will most likely have to employ shielding of various types to protect themselves from the radiation. Although the Martian surface will be a dangerous place for humans, there are some organisms on Earth that could easily survive the radiation on Mars' surface. Take for instance Deinococcus radiodurans. The Guinness Book of World Records title holder for "the world's toughest microbe", D. radiodurans is an extremophile that can withstand environments with limited nutrients and extreme dryness and, most importantly, can withstand extremely high doses of radiation. This microbe can withstand a radiation dose over 1,000 times more than what would be lethal to a human. It can survive in the cooling fluids of nuclear reactors. The microbe's very name stand for "strange little berry that can withstand radiation" while some people like to call it Conan the Bacterium. Indeed, D. radiodurans can even survive in the empty vacuum of space. D. radiodurans would have no problems surviving a trip to Mars and even sitting on the Martian surface. The extreme radiation resistance of D. radiodurans might even make us wonder about alien life that could survive long-term within the emptiness of space. Perhaps there are biospheres where life has learned to launch itself out into space, like little spores traveling between worlds. Perhaps some alien has even adapted to the space environment and become a fully space-fairing creature. What would such a creature look like? Perhaps it would be something like the Tin Man from Star Trek: The Next Generation or Moya from Farscape or perhaps something utterly strange. Would such a creature be anything remotely similar to life as we know it. Would it need to stay close to stars and planets to maintain itself? Those are the questions that bridge between science and science fiction. But we do have good reason to wonder about how organisms get their energy and how biospheres are built. Much of life as we know it here on Earth is built upon the primary productivity garnered by organisms that utilize the light of the Sun for energy, but not all life on Earth requires sunlight to survive.
Life in Deepest Seas and the Curious Blobfish
My graduate advisor, Alexis Templeton, is the head of a team of researchers centered here at the University of Colorado Boulder and including members from several other institutions which have recently been awarded a grant from the NASA Astrobiology Institute to study what they are calling "Rock-Powered Life". Their work will focus on understanding how biology on Earth has come to utilize chemical reactions between water and rocks for sustenance. Life as we know it does not inherently require sunlight to drive primary production. Rock-powered life may be the base of biospheres on other worlds. Take for instance the Galilean moon Europa.
Europa is a small moon of Jupiter that might have some big surprises in store for us. The surface of Europa is a cracked icy shell, maybe 1 to 10 km in thickness, underlain by a deep subsurface ocean. The ocean of Europa may be as deep as 120 km, making it one of the largest oceans in our solar system. In fact, all of the water in the ocean of Europa is more voluminous than all of the water in all of the oceans, and rivers, and lakes of Earth!
Many of us now wonder if the subsurface ocean of Europa holds a subsurface ocean biosphere. Perhaps there are hydrothermal vent systems on Europa's seafloor. Perhaps, much like on Earth, those hydrothermal vent system have become oases of life, where rock-powered life sets the stage for the development of other organisms. Could there be deep sea marine animals on Europa? What would they be like. Here's a crazy creature that might help us answer that question: the Blobfish. These organisms inhabit deep sea environments off the coasts of Australia, Tasmania, and New Zealand. Living where the pressure is several dozen times greater than at the surface, the Blobfish has developed a unique way to maintain its buoyancy. While many fish use gas bladders to control their position in the water column, the Blobfish has body of gelatinous flesh that is slightly less dense than water, allowing the Blobfish to control its buoyancy in deep sea settings. However, when the Blobfish is removed from its natural setting, the one to which it has adapted so well, and brought to the surface, its body structure changes and it basically slumps into a gelatinous mass. This has earned the Blobfish the vote as "The World's Ugliest Animal".
The Blobfish can survive the extreme pressure of the deep sea, but it's only adapted for that environment. When we consider what alien life may be like, we need to be sure we're considering the types of environments where life might have come to be and where life might be best adapted. For instance, what kind of life, if any, could come to live in the environments of gas giant worlds?
Sagan's Floaters and Hunters... and Blowfish
In Carl Sagan's television series Cosmos: A Personal Voyage, he discussed speculations about what types of organisms could come to thrive in the vast atmospheres of worlds like Jupiter:
Floaters and Hunters. What might they look like? Giant balloon organisms? Giant floating whales? In my mind I wonder if maybe such atmosphere-bound life might develop develops defense mechanisms like a blowfish. Maybe the floaters are giant blowfish-like balloons that can change their position in the atmosphere by bringing in or pushing out gas, and maybe they even look something like blowfish, with spikes and other defense mechanisms adorning their bodies to keep them safe from the Hunters. As Carl Sagan said, we can constrain our thoughts about the possibilities for extraterrestrial life through physics and chemistry, but these are truly speculations. Until we have examples of alien life to work with, the best we can do is work to understand life on Earth and try to use what we know of life to understand which environments alien life may have come to call home. We can look at worlds like Venus, Mars, Europa, and Jupiter and ask these questions. We can also look further, to other worlds around stars far away.
Exoworlds and the Possibilities of Perception: The Greater Wax Moth and the Mantis Shrimp
Since the discovery of 51 Pegasi b, the first extrasolar world we've found, our conception of the number of alien worlds that exist in our universe has been radically expanded. As of today, we have found over 1800 exoplanets and that number is always growing! The worlds we've detected around other stars exist in only a small fraction of the space within our galaxy. Considering the number of planets we've found thus far, it has been estimated that every star in our galaxy should have, on average, at least one world. Of course, some may have none and some may have many, but this still leaves a great number of possible worlds and possible environments for the development of extraterrestrial life. What might those aliens look like? Astronomer and artist, David Aguilar of Aspen Skies has been using his artwork to propose some ideas. He creates models of speculative alien life based on his knowledge of life here on Earth and then places those modeled aliens into digitally created worlds. In what ways can we constrain such work, such speculations? Perhaps we can consider something like sensory perception. Take, for instance, the Greater Wax Moth. This organism has the greatest range of hearing of any known organism on our planet. Not only that, but the Greater Wax Moth has a hearing range that lies outside of the range of sounds that we humans hear. It has alien hearing here on Earth. It's evolved such hearing so that it can hear at frequencies up to 300,000 Hz, allowing it to "out-hear" it's natural predator, the bat. Bats use high-frequency sounds in their echolocation. It allows them to "see" what they hear. The Greater Wax Moth has evolved to hear and to speak above the frequency at which bats echolocate. An even crazier creature might be the Mantis Shrimp. The Mantis Shrimp has the greatest perception of light and color of any known organism. While we humans only have 3 color receptors in our eyes, Mantis Shrimp have 16! Writing in his webcomic, The Oatmeal, Matthew Inman has said of Mantis Shrimp that their sight is like a "thermonuclear bomb of light and beauty"! Not only do Mantis Shrimp have the greatest vision of any known organism, but they also happen to pack the hardest punch:
The Mantis Shrimp is a crazy creature. It sees in ways that we can't comprehend and it kills using a deadly knockout punch. Might there be alien worlds where the vision of the Mantis Shrimp is only the beginning? Or worlds where the deadly force of the Mantis Shrimp's punch would be considered puny?
What Beings May Come?
What could organisms like the Greater Wax Moth and the Mantis Shrimp teach us about alien life? What about the Hummingbird, extremophiles like Deinococcus radiodurans, or the Blobfish? When there are aliens such as these living amongst us, perhaps it suggests that the possibilities for life in the universe are endless. I didn't even start to touch on intelligence and consciousness, robots and machine life, or even some of the myriad ways in which microbes might dominate alien biospheres, and yet there are great examples to be found in those realms as well. The bridge between science and science fiction lies not only in imagination, but in considering what may yet come to be. As Carl Sagan mentioned in that video from Cosmos, there is no predictive theory of biology. Not because it doesn't exist, but because we don't yet have enough to go on to determine if there could be one. Maybe life does follow certain rules and we will one day find that many aliens are very similar to us, or maybe life follows few rules and alien life will appear utterly and wholly alien to us. Considering all of the crazy creatures on Earth can help us to constrain our speculations about alien life, but, until we determine if we are or are not alone in the universe, all we can do is continue to look at our one example of a biosphere and say "what might this mean?"
