Imagination is an important part of science, for without it there would be no curiosity. Here we ponder the theory of panspermia. At it’s essence panspermia is a theory which posits that life on earth (or at least it’s building blocks) came from space. How did it get here? Ancient earth was infected in a sense. Compounds and molecules useful to life were brought here by comets or asteroids and dispersed by impacts.
It is only a theory, but it makes sense in several ways. Recent research gives some credence to it. Decide for yourself. I personally believe that terrestrial biogenesis and panspermia can both contribute equally to debate over the origin of life.
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….
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.
From an article in Planetaria, a fantastic blog exploring alien worlds, and my new go-to source of news!
Jupiter’s moon Ganymede is found to be producing some exceptionally strong electromagnetic waves. These waves are known as “chorus waves”, as they can be converted into sound, which we would hear as a series of bizarre chirps and whistles. In fact, they sound like an over caffeinated R2-D2!
The universe talks to us!
Ganymede is the second largest moon in the solar system after Titan, and is larger than the planet Mercury. One of the four Gallilean moons, Ganymede’s magnetic field is internally produced, unlike that of it’s sister moon Europa, whose field is induced by Jupiter’s powerful magnetic field.
This magnetism is the result of a highly differentiated internal structure. This means that like Earth, Ganymede has an active molten core, which interacts with upper layers, and also results in the presence of a subsurface ocean. Earth’s magnetic field is the result of it’s molten core and convection of molten iron and rock through the lower and upper mantle. Ganymede has a similar field but it weighs in at a million times stronger than our own! It’s even more intense than the magnetic field pumped out by its parent Jupiter!
This field results in the generation of powerful auroras, which are a familiar phenomenon on earth.
Ganymede’s complex structure is thought to be the result of a fairly quick formation period. During the formation of the solar system, Jupiter ( the oldest of the planets) was still an accreting cloud of gas and dust: a mini nebula much like the solar nebula forming around it. Within this Jovian nebula dozens or maybe hundreds of smaller worlds were accreting: emerging from the primordial Jovian cloud. Proto-Ganymede accreted quickly, within about 10000 years, and so it’s various layers were unable to disperse and homegenise within the moons structure. This can be inferred from the structure of other Jovian moons such as Callisto, which are shown to have an extremely homogeneous internal composition; indicating a more protracted period of accretion and formation. Most likely on the order of about 100000 years.
Jupiter displays impressive aurora as well. These are the result of interactions betweens it’s magnetic field and charged particles issuing from the highly volcanic moon Io.
Aurora and magnetic phenomena have been observed on exoplanets, in particular on mysterious objects known as brown dwarfs. These “failed stars” are quite common in the galaxy, and present a magnetic laboratory for astrobiologists and planet hunters. They are of considerable interest in this context, as they present an opportunity for researchers to examine an atmosphere that resembles that of both a star and a gas giant planet, all without the pesky glow from a nearby star!
Methods of detection and analysis of exo-magnetic fields such as these will not only aid scientists in understanding the formation of planets and stars, but also in the detection of exoplanets, and assessment of their potential habitability. Remember, life on Earth is protected by our magnetic field, so detection of such fields around exotic new worlds could be a hopeful sign.
Thanks for reading AstroBiological, giving you the universe in plain human. I hope you’ve learnt something today. I know I have, and that’s what it’s all about!
I’ll see you next time!
Yesterday a little light went out from the world. My father in law, Joseph Abela passed away in his sleep.
Joseph hailed from the tiny speck that is Malta; an island nation that has weathered countless storms over the course of its long history. The earliest European civilisations inhabited the archipelago, which sits a stone’s throw away from Italy. Malta has been invaded, attacked, occupied, enslaved and conquered more than its fair share. Through all of this it has persisted. All I can say is these Maltese are tough cookies.
Even now Malta holds its head up high as a tiny but prosperous member of the European Union. A genuine jewel of the Mediterranean I intend to see it one day.
Joseph exemplified the stubbornness that has kept this nation going when all hope has seemed lost so many times. Even during the end, as his life eventually drained away he was fighting: unwilling to give a single inch of ground.
I tell you what, he didn’t care less about political correctness either. He was fun.
Science in recent decades has lost something. It’s headed along a progressivist path, trying to reduce all of human experience and history to nothing more than quantum quirks. Standing with Joe’s large family was a moving experience. Science would like us to believe that we are not much more than collectives of cells, acting as one. Yesterday I saw something more. A life was ending. Experiences, stories, arguments, knowledge: collected over a lifetime of punishment and adversity was fading away with each struggling breath.
When a priest came in and administered Last Rites, I observed something else taking place. As relatives recited prayers and blessings and the priest gave sacraments I saw what human beings have become and are capable of. We are not bags of cells, sloshing across a rocky planet in an indifferent universe. We are stories. We create beauty when we perceive simple things. Emotion, meaning and wisdom have emerged from millenia of evolution.
We are far more than the sum of our parts. In this way emergence is creation.
Joe and everything he was ultimately emerged from the firmament, and yesterday, in a kind of reversal, he reentered the slipstream.
All life depends on information storage and transmission. No ifs or buts. DNA is the weapon of choice these days. It carries the alphabet of life, coding for almost every single permutation of biology that exists. Once, however, it may have had a more versatile forerunner.
RNA, or ribose nucleic acid, is now relegated to worker bee status in the cell. Whilst DNA lords over it’s cellular domain, providing the instructions for just about every single activity in the cell, RNA is now involved in DNA replication, via the processes of transcription and translation. Billions of years ago, however, RNA may have been much, much more.
To explain how, I have to stray from the script a little and talk about the other major players of the cell: proteins. Think of a cell as a kitchen. Where DNA is an executive chef, pretty much doing nothing but writing menus, and telling everyone how things should be done, the proteins are the poor saps slavishly working to the chef’s bidding. Proteins are the kitchen-hands, dishwashers, line cooks and general slaves of the cell.
If you were to look at a protein, you’d wonder why. They have a crazy variety of forms. Just imagine your cat had found a ball of yarn and left a tangled web of yarn all over the floor.
Picture the tangle. That tangle is a shape, really. It’s no different to a square, or a human head or banana or one of those weird dices that Dungeons and Dragons players use. Shape is the key word here. All proteins perform a discrete function. This function is directly tied into the shape of the protein. Most proteins look something like that mess of yarn on the floor. But it goes a little deeper than that.
Ok. So shape equals function in protein. How does RNA or DNA matter here?
If you picture DNA you’re probably seeing some kind of twirly, ladder like structure. That’s pretty much what a DNA molecule is: a twisty ladder; otherwise known as a double helix. DNA’s single function: information storage, is tied into this configuration. RNA is a bit different. It’s one side of that twisty ladder, or a single strand. RNA still works well as an information storage molecule. That’s how it is involved in DNA replication. Short snippets of mRNA, or messenger RNA carry instructions vital to the whole proceeding. Viruses actually use RNA as their core genetic material, not DNA.
RNA has one extra special feature. It can fold and twist into bizarre shapes like protein can. These shapes can bestow upon some RNAs the properties of a special class of proteins called enzymes. Enzymes are catalysts, meaning essentially they just make stuff happen. They kick-start biological reactions, ensuring that the cell works at all. It’s believed that some RNAs can do this, folding and twisting into new forms which are called ribozymes.
Ribozymes are catalytic like enzymes. In the primordial brave new world of ancient Earth there were no complex cells with grand genetic machinery and a retinue of proteins doing DNA’s bidding. Life hadn’t figured out this nifty little double act yet. Back then it was the Wild West. Every bit of biological stuff floating around had to be a generalist, able to do many things: A jack of all trades if you will. RNA may have been one of these generalists. This one little ability of RNA: it’s tendency to get bent out of shape, may have been a boon to the very first life on Earth.
Anchor FM is super fun and easy to use. Download it for yourself! If I can do it, anyone can.
Whilst you’re still here, an article from fellow bloggers moosmosis outlining the central dogma of molecular biology, as alluded to in this post:
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.
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.
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?
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.
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.
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!
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.