Category Archives: astronomy

39 Light Years: Part One

Image: Ben Roberts. Produced with Universe Sandbox

Sometime in the early 2000s, this place was still a speck of data in some astronomers brain. The announcement of a system of seven earth-sized planets was pretty big. The further revelation of three of those worlds sitting within their stars habitable zone was the icing on the cake.

As the first intelligent explorers approach TRAPPIST-1e, we present to you these images: the culmination of decades of waiting, hoping that return transmissions from the TRAPPIST-1 mission wouldn’t get lost in interstellar space. There were those who worried that anything beamed back by the missions wouldn’t even make it out of the system. TRAPPIST-1 is a red dwarf star: a tiny relic of a thing but incredibly ancient. Age estimates range from 8 to 12 billion years old. Red dwarf stars tend to be nasty little suckers, and TRAPPIST-1 is no exception. Extreme solar flare activity sometimes hits the system, as the parent star has a tantrum. Communication from the system is nothing short of a miracle. Nevertheless, here are some of the better images we’ve managed to glean from the stream of data being sent back. Thirty nine years worth. Thirty nine years of waiting.

Approach: A New Red Planet

The very first direct images of TRAPPIST-1 and it’s rocky retinue were messy little blobs of pixels.

Of course, many exoplanets (and exomoons) had been imaged directly using a variety of techniques. The use of coronagraphs to scrape together images from points of light across impossible distances was revealing new vistas for a long time. The following image was taken all the way back in 2004:

A disc of debris around the red dwarf star AU Microscopii. Image: Hubblesite.org

Of course, progress marched on, and as missions approached the system the world waited for new images. A first blurry image sped across the galactic neighbourhood:

A TRAPPIST-1 planet caught in transit across the host star. The faded object to left of centre is an artifact of the imaging process.

This image was a first test. As the mission approached the system, we began seeing more. High quality imaging was held off until final approach, in the interests of energy efficiency.

An infrared and monochromatic direct light image, taken from a distance of approximately 11 AU. Images: Ben Roberts

TRAPPIST-1e was waiting for us.

Image: Ben Roberts

Imaging of exoplanets is explored in a new video, presenting the concept of coronagraphy. Help astrobiology reach the world (this and others) by checking it out. Subscribe and share if you like.

This post is the first of a series taking us on a trip to a real alien world, and speculating on just what it could be like, using real world astrobiology. I hope you like it!

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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

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.

Planet Building: Possible?

If you don’t want to read, then listen! I have put this post up on a podcast I’m doing, available on Anchor FM, as well as certain other outlets.

https://anchor.fm/astro-biological/embed/episodes/Planet-Building-e1ff39

If anyone has read “The Hitchhiker’s Guide to the Galaxy” quadrilogy they would have been struck by some of the big ideas hidden within Douglas Adams’ deadpan humour. One of the heavy concepts that stuck with me was the idea of planet building. According to the story, Earth as we know it today is a planet sized super computer, built to perform one task: to figure out the meaning of life. A planetary architect named Slartibartfast is entrusted with overseeing the rebuild of Earth after it’s destroyed due to a galactic scale clerical error.

space-3288275_1920.jpg

Planet building.

Possible? Why not? According to prevailing theories, planets mainly form via the process of accretion. Simply put, particulate matter adrift in molecular clouds clumps under the inexorable pull of gravity, forming ever larger clumps that clump to ever larger clumps and so on. Eventually a planet or star is the inevitable result.

A newly formed exoplanet (in the dotted circle) orbits a newly formed, newly discovered star: CS Cha. Image: Space.com

Why couldn’t this be done artificially? Would it be even possible? If it’s just a matter of throwing lumps of crud at other lumps of crud and hoping they stick, then why couldn’t it be?

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Scenario:

It’s the future. Humanity lives and works in space. The asteroid belt is the new frontier or wild west. Chunks of formerly useless rock are now homesteads or villages. Distances are not overly tyrannical. An asteroid is typically only a few light seconds from another. However, asteroids can be moved. Bigger asteroids like Ceres, Vesta or Eros would comprise the main hubs of commerce and trade in this new world.

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A new frontier… Image: Maciej Rebisz

Smaller settlements such as these “homesteads” could make life easier for themselves in terms of travel times (and therefore fuel costs) to larger, more important settlements by moving closer. In the frictionless, zero gravity environment that is space this wouldn’t be too technically difficult.

Scenario:

Time has moved on. The asteroid belt is a thriving collective of trade networks and conglomerates of smaller settlements. Smaller asteroids now cluster around larger ones like space junk in low earth orbit. Economically, this proximity is making things easier for everyone, and lots of people are getting rich.

Just imagine though if humans disappeared. The zombie apocalypse hit outer space and spread to all corners of the solar system.

(That’s the fun explanation)

Every living human is gone, and the asteroid belt is now a vast ghost band, forming a wreath around the sun, somewhere between Mars and Jupiter. There are all these swarms of asteroids now adrift, all artificially brought closer together by generations of enterprising human beings No course corrections keep them from colliding and so many of them are doing just that. Orbits decay, and tiny chondrite specks plough slowly into larger planetesimals.

See where I’m going with this? Over time, natural accretion would naturally lead to planets forming, or at least a large moon sized object. In millions of years the solar system could have a tenth planet (let’s just sneak Pluto back into the club. Don’t tell anyone!)

Planet Building! Essentially a garbage planet could form from the artificially placed asteroids and other objects now in very close proximity and drawn by the slow but inescapable pull of gravity.

I think it’s an exciting idea: a real megastructure! The ultimate megastructure!

What next?

This post was inspired by a chance statement in a video discussing space colonies on Isaac Arthur’s Science and Futurism youtube channel. Check it out. Isaac has a huge catalogue of lengthy discussions on some really interesting concepts. Here is a link to the relevant video if you’re interested:

Last but not least, here are links to the social media for Maciej Rebisz, the talented artist behind some fantastic space artwork, including the asteroid colony about halfway down the post.

facebook – https://www.facebook.com/maciej.rebisz

twitter – https://twitter.com/voyager212 – general updates

artstation – https://www.artstation.com/mac – art

society6 – https://society6.com/macrebisz – prints

Join me on my facebook group:

https://www.facebook.com/groups/AstroB/

And on YouTube. I’m not quite up to the standard of the venerable Mr Arthur (yet), but I’m working on it. Help me on this journey and subscribe!

http://www.youtube.com/c/BensLab

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!”