Category Archives: astrobiology

Keeping a Lid on Life?

A comment on a facebook post I put up a few days ago got me thinking about habitability. Moreover, I got to thinking about the parameters of habitability.

We think that life here on earth is fragile, holding on to a thin silicate crust within a fairly narrow range of temperatures and conditions. For the most part it is. Life needs a fairly stable environment in order to keep on keeping on. However, there are plenty of examples of oddballs: extremophiles, that seem to do quite well in some pretty horrible places. The recent discovery of Antarctic microbes that derive energy from air itself expands the catalogue of organisms that could have analogues on other worlds.

Now, extremophiles do well in extreme environments. No brainer there, and there is no shortage of extreme environments in our solar system alone.

Venus is an example, and a good one. Analogous to Earth in size, density, gravity and composition, it differs markedly in others. No magnetic field, no water (at 0.002% of the atmosphere not worth mentioning), surface temperatures that melt lead, and atmospheric pressure ninety two times what we’re used to here. It’s horrible.

Why?

No plate tectonics. On earth we slowly sail about the globe on slabs of continental crust, which happen to be more buoyant than the thicker, denser oceanic crust. Driven by convection of magma in the mantle, crust is slowly pushed hither and thither by tectonic processes such as seafloor spreading.

To understand what this is, imagine a pot of something thick like soup or porridge on a stove top. As the contents of the pot heat up they begin to stir. Have you ever noticed when this begins to happen that as the surface begins bubbling the top layer is forced aside as new material wells up from below? This is seafloor spreading in a nutshell. Magma from within the earth wells up, heated by a radioactive core, and pushes the seafloor aside as it breaks through, forming new crust. The continental plates, perched atop this moving crust, slowly journey across the planet.

Why is this so important to life on Earth? Because our planets interior is so hot, plate tectonics (along with volcanism) is the primary means by which excess heat is released over time. If this didn’t happen, well, you wouldn’t be here reading this and there would be two Venuses in our solar system instead of one.

Venus, or any one of billions of hellish worlds in the Galaxy? Studying worlds like this gives us insights into life here on earth, because it shows just how unlivable other places can be.

For reasons unknown, Venus shut down. It’s core stopped spinning, it’s magnetic field dwindled to nothing and radiation from the sun began a process of stripping the planet of water. Water is a true miracle ingredient. Not only is it a solvent for biological processes, it’s also a lubricant for plate tectonics. Venus seized up and overheated: exactly like a car without oil will do.

A stagnant lid world is one which has no plate tectonics. Climate is seriously affected by such a situation. With no means of escape, heat builds up within, and eventually it becomes an exo-Venus: scorching hot.

Researchers looking at the issue of habitability on exoplanets have looked at the implications of a stagnant lid regime for the possibility of life. Whilst it would obviously be different to life on earth, other factors can lend habitability to a planet.

These other possibilities are exciting indeed. I’ve been exploring astrobiology through images, producing a bunch of pictures. They will be appearing over the next few posts, so I hope you enjoy them. They’re doing well on Instagram!

Thank you for reading the ramblings of a space nerd. The universe is just too intetesting to ignore.

Talk later!

P.S.

Check out my channel!

All images: ©Benjamin Roberts

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Sailed the Ocean Blue

It’s been estimated that a good percentage of planets beyond our solar system may be water worlds.

We here on mother Earth like to think of our blue green marble as a water world. Indeed it is watery, and water is pretty much the reason anything lives here at all. That’s why astrobiologists naturally seek signs of water on exoplanets. “Follow the Water” is a central tenet in the search for extraterrestrial life.

But compared to some worlds, earth really isn’t that waterlogged at all. It’s 0.002 percent water by mass. Only a tiny fraction of that water is available to terrestrial life. That water which isn’t directly involved in biological processes is linked to them, linking life to the planet via seasons and climate.

Some exoplanets are believed to be up to fifty percent water! These are true ocean worlds. To date, up to thirty five percent of exoplanets larger than may be covered by vast layers of water that may or may not harbour life. The jury is well out on that, but the idea is intriguing (and tempting) as the traditional definition of habitable zones is being stretched and reinterpreted.

A water world with a thick atmosphere of steam.

For now, we have only our imaginations with which to explore these worlds…

An aerial view of remote coastline on a hypothetical watery exoplanet.

A new video!

Translations

More images.

I’ve been thinking some of these may look good as posters. Thoughts anyone? They provide another way to reach people, as I myself continue to explore and learn about a truly incredible topic.

I like the look and think my channel will finally benefit from a coherent look and vibe. The retro font works for me, and the surreal, fantastic feel of the pictures is my jam.

Channel News

A new video exploring the possibility of directly imaging exoplanets is coming very soon!

Here is a snippet; sans sound or effects just yet!

More coming.

Images of Astrobiology

The universe is turning out to be a more interesting place with each passing day for me. It’s not all about reading research articles and trawling the internet for interesting news in the vast field that is astrobiology.

I’ve been working on images related to various themes in astrobiology. This field really is a playground for the imagination, and it has something for everyone….

Recent news of a relic subsurface biosphere just beneath the surface of Mars…

Our ones and zeroes formed in starlight?

Something really special here: possible traces of limestones found in the fragments of objects orbiting a nearby white dwarf star…

 

Differing definitions of the Habitable Zone further push the limits of life in the universe..

Svante Arhenius, a swedish chemist and early pioneer of the theory of panspermia..

Ruminations on the code (codes?) that make life possible. How many languages does life have in the Universe?

Does the chemical rich, pitch black seabed of Europa host life? Does that of Enceladus?

 

The first image I created. I hope you’ve like these. There will be more! By the way, the background for this image comes from an online simulator called Goldilocks, by Jan Willem Tulp. His work can be found here. It’s really cool.

Exploring Titan: a Channel Update

My tiny little channel lives! I’m almost at 200 subscribers.

UPDATE: 3rd APRIL 2018

200 Subscribers!

Back to the post.

That is peanuts, but it tells me this channel is definitely trending on an upward trajectory. My most recent video “A Brief History of Astrobiology” is doing well (hint, check it out!)

Watch it for an irreverant look at astrobiology over the ages.

My next one will take a closer look at Titan through the imaginary eyes of its discoverer; Christiaan Huygens, the Dutch astronomer who spied this mysterious moon in 1655. I plan on taking Huygens there for a grand tour. He may even meet his namesake!

huygens_astronaut
What would a 17th century stargazer think upon seeing his high tech namesake, at rest on a frozen plain on Titan?

The tale of Huygens incredible discovery, as well as his amazing mind is worth a single video, and so that’s exactly what this new one is, the story of the exploration of Titan, from 1655 up until some imaginary mission sometime in the late 2020s, when a drone flies through the thick soupy atmosphere of this exotic moon. Maybe (just maybe) a submarine will explore the methane seas that dot the moons northern expanses. I personally can’t wait for both to happen.

Titan boasts liquid hydrocarbon lakes at its north pole
This would be quite a view.

Here are a few screen shots from the upcoming video:

titan drone flight.00_04_24_12.Still005
A drones eye view of titan, seen through a veil of organic haze and interference.
titan drone flight.00_02_49_16.Still004
The drone takes wing, dropped into the atmosphere of Titan. One of the mysterious methane seas can be just discerned through the haze coating the landscape.
titan drone flight.00_05_00_11.Still006
A night time flight over a methane lake. Beneath the frigid surface a small submarine drone looks for signs of methane based aquatic life.

I’m super excited about this one, and I am sure it’s going to be a lot of fun. Stay tuned!

Ben.

An Accidental Ecosystem in Space

Update:

I’m always interested in podcasting, and I’ve created an episode of a tentative series on the Anchor app. It’s just this blog post read out. Convenient for those whom listening is a better way to digest content. Here’s the link:

Listen to my segment “Abandonment among the stars” on Anchor: https://anchor.fm/astro-biological/episodes/Ecosystems-in-an-Abandoned-Megastructure-e1e59n/Abandonment-among-the-stars-a3bp5i

Imagine this. It’s the distant future. Space travellers have discovered a huge structure in deep space. Let’s assume the travellers aren’t human. These beings have stumbled upon the greatest discovery in their history. A vast megastructure, hundreds of kilometres long, it’s a huge cylinder spinning slowly across interstellar space. The structure is a riotous collection of cyclinders, and other smaller structures seemingly thrown together. Tests on the structure reveal it’s very old: several thousand years at least. No signals or signs of current occupation can be found, and it’s determined after several years of examination and debate that the structure is abandoned.
An O’Neill cylinder, adrift in cyberspace.. A 3D model of a physical model I plan to build.
The very first team is sent on board…

What do they find?

The structure is derelict, to say the least. The team can safely determine this. There are no signs of intelligent life.

Mechanisms keeping the cylinder habitable are still somewhat operational. By some miracle of engineering the cylinder still has gravity as well.

But that’s not to say that life hasn’t found a way.
The structure is exploding with life!
The structure is essentially intact. It continues to rotate, driven by some unknown energy source and mechanism. It orbits a medium sized yellow star, lying just beyond the orbital path of the second planet out from this sun. The second planet is completely uninhabitable.
Image: Pixabay

There is a third planet from the Sun which seems habitable. Other expeditions are already exploring that world, and it seems this cylinder was built by whatever sentient beings once lived there.

Image source: Unknown
The structure is an oasis of life, all alone in the night. The builders may have long vanished, but the other organisms they brought on board: whether they be pets, food or pests, don’t seem to know they shouldn’t be here claiming this place as their own. It’s become an accidental ecosystem that has no business being out here and yet out here it is.

….

A couple of weeks I decided to do something different with all the video stuff I do. I did a livestream on facebook and periscope. The topic of my stream was the very question addressed above: what new ecosystems and organisms could arise in an abandoned, livable space station were the human occupants to disappear?

abandoned-factory-1513012_1920

Image: Pixabay

It actually really got me thinking. The whole thing began as a random question on Isaac Arthur’s Science and Futurism facebook group. To my surprise there were a lot of great comments and ideas in response to this question.

I’ve addressed this subject matter before. A blog post explored the nature of interactions between the natural world and those sad, abandoned places on the periphery of civilisation. It’s like discovering a completely new world when I stumble upon these “transitional” places. Imagine finding such a world like the cylinder orbiting Venus. Just how and in what direction would any life on board manage?

It’s a really interesting question, and ties into the nature of life and how it has spread across our own planet. Most life existing today hasn’t arisen spontaneously from the firmament. Nothing’s done that for around 4 billion years. No, life has migrated, hitched rides or been tossed about by catastrophe and happenstance. It has essentially gone where the wind blows, and taken root wherever it has landed. The theory of panspermia relies on this vagrancy to offer an explanation for how life might have appeared here in the first place. I personally think Panspermia is very plausible.

In some ways we’ve seen panspermia in action, from a certain point of view.

This is of course, a very tenuous observation I make, but the principle is the same, using the example of Ascension Island in the Atlantic Ocean. This tiny little mound of dirt popping up from the waves is a giant ecological lab, an ongoing experiment that began over 150 years ago. All manner of species: some introduced, some native, were thrown together, on a barren little rock. Within decades, the island was a lush green paradise, with new ecosystems and new equilibriums. Quite amazing really, and Ascension Island represents a window into the greening of a dead planet such as Mars.

So. To return to the premise of this post. Explorers find a derelict space colony, now overrun by non human life. We’ve seen this on Earth too. Life is especially good at exploiting new niches. When the dinosaurs perished, the mammals that had lived in their shadow for 180 million years suddenly had an entire planet all to themselves. This resulted in the Tertiary radiation, a speciation event rivalling the Cambrian Explosion in the profusion of new species of mammal that suddenly appeared to exploit all this open space. Disaster ecology is an area of study devoted to this knack life has of adapting to catastrophe and finding new balances. Places like Ascension Island are one example of this. Others, like Chernobyl, are another.

03-Chernobyl-animals.ngsversion.1493139603170.adapt.676.1 (1)

Life is doing nicely in the radiation soaked wilderness of Chernobyl. Image: James Beasley and Sarah Webster, National Geographic Creative

So what of my superstructure, adrift in orbit around Venus? It would take several posts to really give it some justice, and so that’s what I’m going to do. A few posts on the post human world in a self contained semi functional space colony.

I must admit I have not been active with this blog lately. I have been busier than usual with new work and things in personal life shifting and changing constantly. It’s never forgotten. This will be attended to, and posts are going to start going up on a more frequent basis. Stay tuned, keep reading and I’ll be writing soon.

Ben.

16 Psyche

My newest video features the bizarre metal asteroid 16 Psyche. This improbable chunk of iron and nickel may one day be mined, yielding metals worth over 10000 quadrillion dollars! No, that figure doesn’t seem real to me either.

Here is the transcript for said episode. I had some fun experimenting with effects for this episode, and I think it works well!

“G’day metal heads!

Do you think you’re rough and tough?

Do you believe you’re made of metal?

hah!

See if you can outmetal THIS monster! A ball of metal mayhem 200 km across! Let’s go check out 16 Psyche!!!

Long long ago, in a molecular cloud not so far away….

The Solar System: Episode 1

It is a time of turmoil in the newly formed solar system. Planets, moons and other heavenly bodies have coalesced from the primordial cloud. As larger bodies fall into orbit around a blazing new sun, smaller worlds are caught up in a system wide spree of destruction known as the Late Heavy Bombardment.

It is a perilous time for a planetesimal or moon, and many smaller planets are destroyed in the cataclysm.

A lone youtuber known as Ben has ventured out into the Big Empty, to visit the long dead core of one such world. Upon reaching it, he sends in a gallant drone to investigate….

Yes Sir! Here we are. Welcome to 16 Psyche. An oddball world really. This place is special for a few reasons.

Discovered in 1852 by the Italian astronomer Annibale de Gasparis, 16 Psyche was named after Psyche, a figure from ancient Greek mythology. The word itself means “Soul”.

16 Psyche is pretty big: a ball of metal over 200 km in diameter! It’s almost entirely nickel and iron to be more precise, although about 10 percent of its surface is strewn with silicate rock much as you’d find here on good old earth.

So this ball of tinfoil from hell comprises nearly one per cent of the mass within the asteroid belt where it lives. It actually lies roughly halfway between Jupiter and Mars, about 3.3 AU from the sun.

What’s an AU?

AU is a very common astronomical term. It means “astronomical unit’. 1 astronomical unit is defined as the distance between Earth and the Sun. This is about 93 million miles or 150 million kilometres. At 3.3 AU this means 16 Psyche lies some  308 million kilometres from the Sun.

Wanna know what’s really special about this metal asteroid?

Two things.

First of all, 16 Psyche is extremely valuable. All of that iron and nickel within has been valued at over 10000 quadrillion dollars!

Obviously that means a lot of folks would love to mine it for all that metal.  A whole bunch of companies have sprung up in the last few years, looking to cash in on asteroids: the next big thing!

Personally, I don’t care about all that. You wanna know what’s really cool about 16 Psyche?

It’s the exposed core of a long dead protoplanet; the remains of a tiny world maybe 500 km in diameter. This tiny planetoid took a beating during the Late Heavy Bombardment, some 4 billion years ago. In fact, this nameless world may have been impacted by other large bodies up to 8 times. This pounding shattered the outer crust, sending scattered fragments out into the newly forming asteroid belt and leaving behind an exposed core. Scientists would love to study 16 Psyche, because it can teach us a lot about planet formation and how planets work- including our own.

Just look at it!  Imagine walking on the core of a planet. 16 Psyche gives us an opportunity to see into our own world in a way. It’s like a time capsule: a snapshot of a newly forming planet, frozen in time for ever.

This is the real value of 16 Psyche, this frozen soul. Let’s take one last look and imagine actually being there….

Outro!

I hope you’ve enjoyed watching this episode. It was super fun to make, and if you got something out of it, then subscribe to this channel for more. Join the astrobiological Facebook group, find me on Twitter. Links in the description.

AstroBiological: giving you the universe in plain human. See you next time!”