Sharing life with the planets next door

October 30, 2018 by Starre Vartan, Astrobiology Magazine
An artist’s impression of the TRAPPIST-1 planetary system. Credit: SETI Institute

How life could be shared between planets in close proximity to one another has received a greater insight thanks to new analytics based on previously known and new calculations. The findings are allowing researchers to understand how likely life might be on a given planet in such tight-knit systems if that world shows signs of habitability.

It began with a blasphemous-at-the-time idea: that life exists throughout the universe, and it can travel without supernatural interference. Anaxagoras, a 5th-century BC Greek philosopher, called this concept 'panspermia'. Kelvin, Helmholtz and Arrhenius advanced the idea in the 19th and 20th centuries by examining how life could be carried to and from Earth. In 2009, Stephen Hawking went beyond our solar system with the idea when he suggested that "Life could spread from planet to planet or from stellar system to stellar system, carried on meteors."

Dr. Dimitri Veras, an astrophysicist at the University of Warwick in the UK, and lead author of a new paper on the subject, says that, "Within the last century, [panspermia] has been focused on life transport within the solar system, including Earth."

The TRAPPIST-1 system, which is 41 light years away and includes seven planets packed into an orbit smaller than Mercury's, changes this Earth-centric idea. The TRAPPIST-1 sun is an ultra-cool red dwarf, so even though the seven nearby planets orbit closely, they are possibly all still in the for life, to varying degrees depending upon the make-up of their atmospheres. That makes them a perfect model for exploring the idea of panspermia, per Hawking, anywhere in the universe.

Three stages

But back to our solar system, where the "foundation for panspermia-related processes has been established," according to Veras' paper. That includes evidence that life can survive the three stages of traveling from one planet to another: initial ejection, the journey through space between planets, and impact onto a new planet. Each stage presents challenges to the survival of life, of course.

The orbits of the planets of the TRAPPIST-1 system are tightly arranged, especially when compared to our Solar System or even the moons of Jupiter, increasing the chances that life could be shared between them. Credit: NASA/JPL–Caltech

Veras wanted to create an analytical system to quantify each of these parts to create a better understanding of the probability of the whole.

He had some information to start with: Microbes can possibly survive ejection from a planet with life on it, as per previous studies, and even a voyage through interplanetary space, if shielded from the radiation and cold. Less is known about how well a microbe that endured space travel could survive impact on a new planet, which would be necessary for life to complete the voyage from one planet to another.

Since impact includes more unknowns than ejection and transit between planets, Veras had less-detailed information to work with in this area of his calculations. "The physics of re-entry features complexities that are not present with the ejection and voyage phases through space," he says. "For example, frictional heating during re-entry can lead to the formation of a fusion crust [the outer layer of the meteorite that melts and ablates during atmospheric entry] on the surface of the meteorite."

When it came to figuring out how to calculate the tricky physics of atmospheric entry onto a new planet, Veras tells Astrobiology Magazine that, "Equations regarding the physics of impact have already been established and used for solar system applications [so] we converted those for use in a general extra-solar system."

To understand the probability of ejected material traveling from one planet to another, Veras combined his equations into analytics as a way to figure out the whole system of panspermia, not just parts of it.

"Usually, the dynamics of panspermia is studied with numerical simulations, however, these can be slow to run and must be tailored to an individual system," says Veras. "Alternatively, analytics are much faster to use and are general enough to be applicable to a wide variety of systems."

Sharing life

Now that there's an observable multi-planet system – TRAPPIST-1 – with more than one world in the habitable zone, astrobiologists can use these analytics to understand the probability of life being shared between planets in these extra-solar locales. The closeness of the planets in this new system means that the chance they can share material is high. Can Veras' analytics guarantee that, if life began on one of the , that life may then existor not exist thanks to panspermia on a given planet? His equations are not meant to do that – Veras admits that they are "not exact," but "provide a sufficiently good approximation," – but rather their aim is to give astrobiologists another tool with which to assess new planetary systems.

Amaya Moro-Martin, an astronomer at the Space Telescope Science Institute in Maryland, who has previously published a paper on the probability of panspermia between different planetary systems, says Veras' analytics are "An impressive piece of work that takes into account a wide range of physical processes that are involved in panspermia."

Looking forward, Moro-Martin thinks Veras' work will be useful for when new planetary systems are discovered. "The framework that it establishes will help others assess whether, from the dynamical point of view, could have been feasible, given the system characteristics," she says.

Astrobiologists need to ensure that they are not limiting to what's already known; aliens could look very different from what we expect. ""The difficulty here is that the experiments that test survival against the hazards of outer space and atmospheric entry will be based on the organisms we are familiar with, and we have no clue what extra-solar organisms might be like," says Moro-Martin, "which opens a fascinating world of possibilities."

Explore further: Planet Nine could spell doom for solar system

More information: Dimitri Veras et al. Dynamical and Biological Panspermia Constraints Within Multiplanet Exosystems, Astrobiology (2018). DOI: 10.1089/ast.2017.1786

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Mark Thomas
3.9 / 5 (9) Oct 30, 2018
IMHO, the exchange of viable bacteria between planets is at least part of what is happening out there. The universe existed for about 10 billion years before the first signs of life are known to have appeared on Earth 3.8 billion years ago. If life could arise independently on Earth after 100 million years or less after it cooled enough, that it must have arisen in countless other similar places. That bacteria evolve into every possible niche, including surviving time in space, seems very likely to be correct. Bacteria like Deinococcus Radiodurans probably evolved to survive a journey in space because it can withstand thousands of times the radiation encountered on Earth and remain viable. Evolution does not retain useless features, such a cave fish that are blind.

https://en.wikipe...iodurans

Note that I fully expect the true picture to be more complicated than simple panspermia with life arising on and traveling between planets to some degree.

rrwillsj
1.2 / 5 (5) Oct 30, 2018
Oh geez! We're back to refusing to eat beans because they resemble the human liver.

It is amazing how generation after generation of fabulists can keep reviving the rotting corpse of the panspermia myth.

"... Bacteria like Deinococcus Radiodurans probably evolved to survive a journey in space ..."

Or, probably not. That neither Venus nor Mars, have to date, displayed any signs of excretions from existing thriving communities of Earth-type micro-organisms. After billions of years of opportunity to colonize our neighbors.

The bad news for those counting on Deinococcus Radiodurans is that they consume free oxygen for energy. Besides Manganese DR relies on gaseous Nitro-Oxide for it's defensive processes.

- cont'd -
Mark Thomas
4.3 / 5 (8) Oct 30, 2018
neither Venus nor Mars, have to date, displayed any signs


Wrong. There have been suggestions of bacteria in the clouds of Venus and bacteria-created methane emitted from Mars. Nothing definitive just yet, but that may be because there are too many people like you who do not understand the benefit of exploring our solar system to support finding out. If you understood this, you would have realized there is not enough evidence to draw firm conclusions either way. To get that evidence we are going to have to boldly go where no one has gone before, just like my comic books say. :-)
rrwillsj
1.2 / 5 (5) Oct 30, 2018
- cont'd -

Which brings us to the simplest explanation for the DR genera.
They evolved out of proto-organisms forming at the end of the Hadean Epoch. From the same root stock of chemical reactions as all other existing lifeforms. They evolved resistance to high levels of radiation from constant exposure to a steady diet of Solar UVB rays. When no protective layer of ozone existed. Combined with constant exposure to a planetary crust still infused with decaying radioactive metals.

DR adapted to the Great Oxygenation, when most other competing organisms died. As oxygen-consumers, DR found a comfortable environment among all the early cyanobacteria.

No outer-space boogeyman needed. No contortionist leap of logic or faith needed to explain why we all use the same basic prion-RNA-DNA structure.

If you choose to believe different? Your extra-ordinary claims of miraculous mumco-jumbo will need to produce extra-ordinary and verifiable proof.
Mark Thomas
4.1 / 5 (8) Oct 30, 2018
Your extra-ordinary claims of miraculous mumco-jumbo will need to produce extra-ordinary and verifiable proof.


I stated my humble opinion, I have not made "extra-ordinary claims of miraculous mumco-jumbo." But it doesn't matter because I think we agree we "need to produce extra-ordinary and verifiable proof."

The only way to get that proof is to (repeat after me) boldly go where no one has gone before.
rrwillsj
1.2 / 5 (5) Oct 30, 2018
Okay, that sounds like a reasonable slogan for crowdsourcing your own space project. NASA has been requesting proposals of payloads for for future launches.

Opportunity is knocking, Mark. Answer that call to destiny! Gather together online with your soul-mates and bitcoin innovation. The only failure is failing to make the effort.

Mark, it may appear that I am insincere but actually I am mocking my own failed ambitions.
Surveillance_Egg_Unit
2 / 5 (4) Oct 30, 2018
@Mark Thomas
The whole purpose of the formation of planets is to provide for the Life Forms that will follow the formations under the right conditions. Otherwise, what would be the sense in planet formation at all if nothing but rocks and hills were to be on and in them.

There is a purpose for everything; even the Universe has a purpose.

There is no way to "peer-review" these theorem and theorem is all it is, but to understand the theorem, one has only to have faith in its potential reality. For those without that faith and demand validated evidence - you are out of luck, for there is only what your human eyes can detect.

There may, indeed, be Life living on the planets of Trappist-1. And it may have turned out that way by Design if such is true.
But again - no peer-review and no papers to be submitted. If there is sentient Life there on those planets - well, that is a wonderful thing. I would love to meet them for a pint of two.
Captain Stumpy
3.7 / 5 (6) Oct 30, 2018
@egg-brained creationist fanatic
The whole purpose of the formation of planets is
everything past this point is speculation based upon your beliefs

it has absolutely no scientific value, nor does it have any evidence, let alone the ability to validate
and theorem is all it is
strawaman based on ignorance of terminology

a scientific theory is:
an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results
Established scientific theories have withstood rigorous scrutiny and embody scientific knowledge

The meaning of the term scientific theory (often contracted to theory for brevity) as used in the disciplines of science is significantly different from the common vernacular usage of theory
- wiki (see references as well)

you don't understand what a theorem/theory is
Surveillance_Egg_Unit
2.6 / 5 (5) Oct 31, 2018
Sentience in humans is natural due to humans being animals through the sharing of DNA/RNA with animals.

"Sentience is the capacity to feel, perceive or experience subjectively.[1] Eighteenth-century philosophers used the concept to distinguish the ability to think (reason) from the ability to feel (sentience). In modern Western philosophy, sentience is the ability to experience sensations (known in philosophy of mind as "qualia"). In Eastern philosophy, sentience is a metaphysical quality of all things that require respect and care. The concept is central to the philosophy of animal rights because sentience is necessary for the ability to suffer, and thus is held to confer certain rights."

To feel is to be a sentient animal; to think and reason is to be human. If there are Life Forms on other planets who think and reason, then they are our brothers and sisters. If not, then they are akin to animals and should still be treated with respect.
Surveillance_Egg_Unit
1.8 / 5 (5) Oct 31, 2018
@Mark Thomas
My S_E_U theorem is that the Universe and all that is within it - the Stars, planets, moon, asteroids were created and allowed to evolve for a purpose. That purpose is for Life to come into being and to evolve, grow and progress. Without that Design, all would be chaos, as rrwillsj believes, and this planet would have been demolished at sometime in the past 4 billion years, notwithstanding the animals living on it. But it is still here - alive and well - and this planet's Design has evolved from its beginnings in order to accommodate Life - past, present and future. Humans are still being watched over and their actions are still being monitored by those who are watching them. There is nothing to peer-review or write a paper on regarding the advent of the human in its design, as there is no evidence in the fossil record that homo sapiens ever existed - except for the fossils of human-like animals in Africa.
The Creation is science of the highest order. That is fact
Mark Thomas
3.8 / 5 (6) Oct 31, 2018
my own failed ambitions.


Me too, I am sorry to say. Obviously I will never make it to Mars, but somebody might. An Elon Musk-powered NASA is probably our best option for somebody reaching Mars in the 2030s. If that happens, I suspect most of us will be surprised at how good that makes us feel. It hardly ever gets discussed, especially these days, but deep down I think most of us want to be proud of the human race. Reaching Mars will give us an opportunity to be proud, at least for a little while.
Surveillance_Egg_Unit
1.8 / 5 (5) Oct 31, 2018
-contd-
IF there are sentient and/or thinking and reasoning Life Forms in any of the planets of Trappist-1, then they were also created by Intelligent Design for the purpose of populating those planets that can support Life. This is what it is all about - the existence in the Universe of Stars and hospitable planets. Otherwise, the Universe itself need not exist.
Some believe that existence is only a dream, but that also cannot be peer-reviewed.
Surveillance_Egg_Unit
2.6 / 5 (5) Oct 31, 2018
A soft landing on Mars with humans on board would be a triumph after 300,000 years of homo sapiens evolving and progressing on this planet. Going to another planet is what humans were created to do, after all. Humans were not created to just sit on the Earth and vegetate like a lump on a log, so to speak. They were made to explore and discover the Universe, starting with nearby planets and moons, and then future generations onward to the stars.
Surveillance_Egg_Unit
1.8 / 5 (5) Oct 31, 2018
@Mark and rrwillsj
I apologise. I seem to have walked in on a private conversation between you two. I will go now. Carry on.
Mark Thomas
4 / 5 (4) Oct 31, 2018
SEU, the fact that the laws of physics and chemistry are sufficiently tuned to permit life has suggested to some that our universe is part of a vast multiverse, with most universes being dead. While we ponder such deep mysteries, what we can do is reach Mars to look for life there. We can also send probes to look for bacteria in the atmosphere of Venus and the geysers of Europa and Enceladus. Eventually, we should be able to get people to all these worlds. In fact, I suspect we will have done a decent job exploring the solar system with people, not just machines, before we are finally ready to go interstellar.
Mark Thomas
3 / 5 (2) Oct 31, 2018
SEU, no apologies necessary.
FredJose
1.4 / 5 (9) Oct 31, 2018
Unfortunately for the researchers or ANYONE else wanting to claim life on earth is a result of panspermia, there is the two tiny little issues to consider:
1. No matter where they want to originate life from in outer space, somehow, somewhere it has to erupt naturalistically via random chemical and physical processes all by itself. Something which we know for sure is simply not possible since it has to violate all the most basic principles of chemistry, physics, biology and information science that we have firmly established already.
2. Having somehow super miraculously gotten that life from dead materials, they are then stuck with the other impossible act: having to "evolve" it from its simple form to all the other complex lifeforms we see around us. There is just no supporting observational evidence that this can happen. Random mutations and natural selection cannot design new life-forms with new functionality, integration, repair and deployment. Just cannot happen. Period.
FredJose
1.4 / 5 (9) Oct 31, 2018
@Mark Thomas
If life could arise independently on Earth after 100 million years or less after it cooled enough, that it must have arisen in countless other similar places.

Sorry to disappoint. It cannot arise all by itself from dead materials. Fullstop.

@rrwillsj
They evolved out of proto-organisms forming at the end of the Hadean Epoch. From the same root stock of chemical reactions as all other existing lifeforms.

Sorry, no they did not. It's impossible for life to arise from dead materials all by itself - and that's a scientific fact!
Mark Thomas
4.3 / 5 (6) Oct 31, 2018
FredJose, your beliefs are your beliefs, but as you have probably been told more than a few times, science does not work that way.
rrwillsj
3.7 / 5 (6) Oct 31, 2018
Oh freddy. You are confusing "dead" with "inert".
Normal chemical processes are "energetic".
Normal bio-chemical processes are "dynamically energetic".

Your primitive superstitious belief that chemistry is "dead" is just plain stupid. Something has to be "alive" first, before it can be "dead"! You are contradicting yourself.

Normal chemical reactions, in endless variations of processes, across tremendous spans of time. Those random events producing the first prototypes of bio-chemical processes. Mostly failures even at that simple a level of pre-life. Eventually, after millions of years of countless flounderings & founderings, one of the first organisms survived to reproduce. "That's My Daddy!"

freddy, you really need to reconsider your concept of the supernatural. Your descriptions for the accomplishments of the deities are as tiny & trivial as your intellectual efforts.

All you accomplish is proving my Theory of Stupid Design is a truism!
Surveillance_Egg_Unit
1.8 / 5 (5) Oct 31, 2018
SEU, the fact that the laws of physics and chemistry are sufficiently tuned to permit life has suggested to some that our universe is part of a vast multiverse, with most universes being dead. While we ponder such deep mysteries, what we can do is reach Mars to look for life there. We can also send probes to look for bacteria in the atmosphere of Venus and the geysers of Europa and Enceladus. Eventually, we should be able to get people to all these worlds. In fact, I suspect we will have done a decent job exploring the solar system with people, not just machines, before we are finally ready to go interstellar.
says MarkT

1.Yes. To your first statement. The laws of Phys and Chem are well tuned to permit Life to emerge from those chemicals. BUT those laws are not sufficient to GIVE LIFE to those chemicals.
If they were able to give life to chemicals, then there would be a constant emerging of NEW Life Forms on Earth wherever and whenever such chemicals congregate.
Surveillance_Egg_Unit
2 / 5 (4) Oct 31, 2018
-contd-
2.Multiverse is pure speculation, and so is their being dead.
3.Reaching Mars is within human grasp, as long as a way is found to protect humans from solar and cosmic rays on the trip to Mars, as well as the effects of weightlessness on the human body.
4.Probes will be continued to be used for discovery of possible Life on other planets and moons.
5.Machines can be used to terraform and build shelters for humans, and of course - computing.
6.Far into the future (hopefully), Earth may not be livable for humans and animals for whatever reason. Therefore it is imperative that humans find new homes on new planets and seek those around other Stars.
That is why humans were created beyond sentience and given the capacity to think and reason - something for which chimpanzees and other primates are not endowed.
There are those who choose to align themselves only within the box of chimps and gorillas and that certainly is their freedom to choose.
Surveillance_Egg_Unit
2 / 5 (4) Oct 31, 2018
Which brings us to the simplest explanation for the DR genera.
They evolved out of proto-organisms forming at the end of the Hadean Epoch. From the same root stock of chemical reactions as all other existing lifeforms.
says rrwillsj

And what was that rootstock, williejoe? Even biologists and anthropologists, etc. are unsure what the original chemical makeup was that that conglomerate of chemical synthesisers were made up of, that allegedly came together and suddenly manufactured a single-celled organism to begin absorbing nutrients and removing waste.

@FredJose
"Dead material" doesn't suit the chemicals that allegedly manufactured a single-celled organism. The chemicals were not dead. They had never lived - so they could not have been "dead".
"Lifeless" is more objective, in my view, but even that is too related to "dead materials". I will try to find a better description for those chemicals. Please try also.
Surveillance_Egg_Unit
2 / 5 (4) Oct 31, 2018

Normal chemical processes are "energetic".
Normal bio-chemical processes are "dynamically energetic".


Chemicals are merely molecules of elements such as Calcium, Carbon, Hydrogen. Nothing alive.

Your primitive superstitious belief that chemistry is "dead" is just plain stupid. Something has to be "alive" first, before it can be "dead"! You are...


As has been explained to FredJ in my previous post. Chemistry has nothing to do with "superstition".

freddy, you really need to reconsider your concept of the supernatural. Your descriptions for the accomplishments of the deities are as tiny & trivial as your intellectual efforts.

All you accomplish is proving my Theory of Stupid Design is a truism!
says williej

There is no such thing as "Deities". You are fond of putting your own words into FredJ's posts. There is only ONE Creator God, which is what you and others will suddenly realise when the time comes of your own death.
torbjorn_b_g_larsson
4.2 / 5 (5) Oct 31, 2018
IMHO, the exchange of viable bacteria between planets is at least part of what is happening out there. If life could arise independently on Earth after 100 million years or less after it cooled enough, that it must have arisen in countless other similar places.

Note that I fully expect the true picture to be more complicated than simple panspermia with life arising on and traveling between planets to some degree.


Well considered comment. FWIW, the genetic repair abilities of [i]D. radiodurans[/i] and similar species have arguably been traced back to evolution for drought survival. The radiation hardiness is likely a side effect.

I would agree on the panspermia, million year travel times are problematic and since 1 out of 10 comets likely are from other systems: "where are they?" Transpermia is more likely, but our unique LUCA shows that it did not happen to us (or is finetuned low frequency).
torbjorn_b_g_larsson
4.2 / 5 (5) Oct 31, 2018
And so for the creationists:
- Your idea is not scientific (truthful), so give it a rest. Besides, we now know that the universe, objects and events, are 100 % large scale mechanistic, so 'gods' is a no go idea anyway as they cannot possibly exist as envisioned or physics need huge rewrite.
- We now know that the multiverse is the most likely explanation for parameters in 'finetuned' laws since inflation was cross tested and slow roll inflation was the remaining physics in Planck final data release; remaining tensions were shown as no show stoppers.
- We know that life emerged from geochemistry because that is how it could happen and phylogenies confirm that. Terrestrial planets are iron, magnesium, silicon and oxygen; iron goes to the core, hydrogen to space, making organics from serpentinization (alkaline hydrothermal vents) so life is inevitable: likely blame the multiverse.

[tbctd]
torbjorn_b_g_larsson
4.2 / 5 (5) Oct 31, 2018
[ctd]

- Darwin knew already a century ago that LUCA was likely, since organics will obviously now be eaten (and we also now know that the planet is changed and organics mostly produced by carbon hugging life). This basic fact is old and truly Biology 101, demonstrating that you comment on a subject you know nothing about but are using erroneous, long rejected arguments taught by your religious leaders and having nothing to do with the state of the science.

Again, sorry to say that religion has become like astrology and homeopathy, not only superstition but demonstrably false idea, but that 'attack' on your core belief by nature is no reason for you to attack the messengers. Facts and science are what they are, you want nothing of it, and we nature and science interested want nothing of your snake oil. So give it a rest.
granville583762
2.3 / 5 (3) Oct 31, 2018
in familiar of syntax
torbjorn_b_g_larsson> And so for the creationists
Zzzzzzzz
5 / 5 (3) Oct 31, 2018
Exchange of bacteria has already occurred in this solar system. Each time we send up something that goes to another planet (I believe we have done this several times on our moon, several times on Mars,. at least once on Venus, and once on Jupiter) we are engaging in this process.

Survelliance Egg Unit and Fred Jose are the sort who celebrate ignorance, and are as good as brain dead. If they are not already on your ignore lists, you are simply masochistic.

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