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april 30th seminar transcript

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(19:07:28) SpookyZalost: Greetings and welcome to the seminar: Introduction to Astrobiology.
For those of you that don't know me, I am SpookyZalost.
(19:07:41) SpookyZalost: I am an astrobiology enthusiast and hope to become a doctor of astrobiology at some point, it's a fascinating albeit still very young field of space science which draws from many other fields including geology, biochemistry, biology, electromagnetism, astronomy, physics, and palaeontology.
(19:08:14) SpookyZalost: There are a lot of interesting topics and sub interests in this field some things you may have heard of include exoplanet hunting, particular the viability of life on said planets.
(19:08:18) SpookyZalost: the search for life on mars
(19:08:23) SpookyZalost: and how life develops in Exotic Conditions
(19:08:49) SpookyZalost: Astrobiology as a whole affects a lot of different fields and it opens up our view of not only the universe but how we came to be on this planet.
(19:09:03) SpookyZalost: Someday it may even lead to the answers to questions about how life originally developed on earth as well as other worlds.
(19:09:21) SpookyZalost: so the first question.
How does astrobiology even work when we don't fully know if there is life on other planets besides earth?
(19:10:05) SpookyZalost: well that's a very good question to ask.
To start with life gives off certain chemical readings and stands out compared to a dead world.
Though our technology is only just reaching the point where we can actually pick those traces out.
(19:10:33) SpookyZalost: Furthermore, there are other things to consider as well.
A lot of groups are looking for earth like life, that is to say Carbon Amino Acid chains forming with H20 or Di-Hydrogen Monoxide as a solvent.
(19:10:55) SpookyZalost: But earth life could have very easily formed very similarly with ammonia or methane as the solvent for the chemical bonds.
(19:11:15) SpookyZalost: that's the funny thing about carbon, it can form complex structures very easily and DNA is just one of many variations of them.
(19:11:51) SpookyZalost: for example, TNA, yes just like the timelords of doctor who, also known as Tri-oxyyriboneucleic Acid, is a very real thing and has been constructed artificially in laboratories, but that does not mean it cannot form naturally.
(19:12:27) SpookyZalost: and carbon doesn't even have to be the base of life either.
Some notable examples include Silicon, Sulfur, Hydrogen, Phosphorus, and Arsenic.
(19:13:26) SpookyZalost: There's also the possibility for photon chains to carry the same types of information under the right conditions since crystallized light does form under the right conditions in labs here on earth.
so with sufficient em fields and pressures, say like in a star, you could have photon based life.
(19:14:06) SpookyZalost: That's the truth of it, life doesn't have to form on earth like worlds, in fact what we call life is such a diverse concept with so many possible variations and combinations it needs a whole field dedicated to it.
(19:14:37) SpookyZalost: even more interesting is that the conditions required for it to arise are so varied that it really boils down to something very simple.
(19:15:13) SpookyZalost: #1 does the pre-requisite combination for a type of life exist on a planet or planetoid which it's trying to form on.
that is to say, does the right combination of chemicals and conditions exist where life is trying to get started?
(19:15:38) SpookyZalost: #2 is the planet's environment stable enough for long enough to maintain complex molecular chains so that they can increase in complexity and grow?
(19:15:54) SpookyZalost: can the life exist long enough for it to take over the environmental management process?
(19:15:59) SpookyZalost: #3
(19:16:11) SpookyZalost: #4 can life adapt quickly enough due to the chaotic environment all early planets have?
(19:16:30) SpookyZalost: and #5 is there a risk of something nearby wiping it out regardless of it meeting the previous criteria
(19:17:07) SpookyZalost: the first two explain why life couldn't form on earth until the solar system became stable enough without random planetoids and stuff smashing into each other.
(19:17:53) SpookyZalost: the third and fourth have to do with the gaia hypothesis or the theory (which is becoming more and more proven the more we know), that life exists solely to maintain it's own existence and grow until such time as it can expand outwards, or perish in the process.
(19:19:00) SpookyZalost: and the fifth relates to extra planetary and extra stellar dangers such as rogue and off orbit planets/planetoids, (see earth's moon and it's creation), Black holes, neutron stars, random high energy bursts that vaporize atmospheres and damage chemical bonds, and other such dangers to life.
(19:20:12) SpookyZalost: Considering all this you can actually eliminate many targets to look at for life harboring worlds.

so you can stick to the middle range of stellar classifications, no brown dwarf stars or super large stars because life couldn't develop there naturally and in the case of super large stars, there wouldn't be enough time.
(19:20:34) SpookyZalost: you can also eliminate planets around neutron stars, black holes, as well as star clusters that contain such objects and other dangers.
(19:20:42) SpookyZalost: this relates to the concept of galactic habitibility zones.
(19:21:55) SpookyZalost: once you narrow that down there's still a lot of things to consider before determining a planet's chances for having life.

at this point however it becomes muddled because carbon/H2O based life is all we really know and the rest is mostly scientifically grounded speculation.
(19:22:34) SpookyZalost: now the traditional habitability zone is for earth like planets, where liquid water exists and stars aren't roasting planets alive due to the distance from the planet to the star and such.
(19:23:24) SpookyZalost: but there's another concept called the extended habitable zone which takes other factors into account including sub surface oceans, thick atmospheres, variable distances, and other such factors which would allow life to maintain stable environments, though not always with as much complexity as we have here on earth.
(19:23:55) SpookyZalost: taking that all into account it's likely there is microbiological life of a wide variety throughout the universe, and possibly even oceanic and plant like life.
(19:24:35) SpookyZalost: and there will be complex life harboring worlds made up of very different substances than what we know of, methane and hydrogen is a good example that we can study in our own system with saturn's moon titan for example./
(19:25:38) SpookyZalost: many of these places would be truly alien and traditional thinking would have you believe these to be dead rocks where life simply cannot exist, but this is really untrue given all the variations and possibilities.
(19:26:25) SpookyZalost: moving the conceptual and scientifically driven theories aside though there are other factors we know can affect life as we know it as well.

so narrowing down to earth like planets with oxygen/nitrogen atmospheres, liquid water, and abundant carbon.
(19:26:34) SpookyZalost: there's still a lot of variety there as well
(19:27:37) SpookyZalost: photosynthetic life like plants here on earth for example is heavily affected by the type of radiation a star or stars a planet orbits emits.
our G type star just happens to emit far less in the green spectrum than in the red and blue spectrums thus most plants are green on earth.
(19:28:13) SpookyZalost: however around an M type red dwarf star for example plants would most likely be black/red simply because that's where the majority of the light is emitted, and would probably be very vibrant in the infra red spectrum.
(19:28:44) SpookyZalost: though given the lower energy outputs, it's also likely that those "plants" would use hybrid energy sources.
a good example of that on earth would be the venus fly trap, or the pitcher plant.
(19:29:42) SpookyZalost: while worlds orbiting much brighter stars would have brighter more vibrant plants than what we see here on earth because they would need to reflect more of the radiation to protect themselves, would probably form thicker membranes, and grow more densely.
(19:30:05) SpookyZalost: that's just one example of the many factors that affect how life develops on a planet over time
(19:30:18) SpookyZalost: another factor to take into account is the size and density of a planet
(19:31:19) SpookyZalost: on places where gravity is lower for example plant and more importantly animal life would grow larger due to there being less limitations and less dense frames required to efficiently move so life will take advantage of the longer strides and larger heights reached without as strong a limitation.
(19:31:49) SpookyZalost: the opposite is also true for larger higher gravity worlds and would have smaller more densely structured, and possibly armored life.
(19:32:10) SpookyZalost: you also have to take into account the types of environments that these types of worlds would be more likely to harbor
(19:33:26) SpookyZalost: it's been shown that smaller worlds typically don't have tectonic activity for example and so life would have to do more work to maintain a constant equilibrium since the planet won't be providing it as much, furthermore large regions of vulcanism would exist on these worlds.
a good example would be mars, where life unfortunately couldn't maintain that balance.
(19:34:21) SpookyZalost: while larger worlds would have more active tectonics, probably again a bit more vulcanism but it would be spread out more.
and most likely stronger magnetic fields as well which means to a point larger planets would be more friendly to life than smaller ones.
(19:34:55) SpookyZalost: though their higher gravity would also bring down more extra-planetary threats such as meteors.
(19:35:55) SpookyZalost: despite all of these variables we cannot be 100% sure, though that truth is changing, titan is showing signs of at least proto-bacteria like biomolecules, and there's possibilities under the icy moons and planteoids throughout the system for liquid oceans heated by tidal pulls and tectonic activity.
(19:36:53) SpookyZalost: and life basically requires the following.
a stable environment of some sort that it can stabilize further.
energy, thermal and photonic seem to be common from what we know so far making this a very broad region.
(19:37:05) SpookyZalost: stable chemicals that can bond in long chains
(19:37:21) SpookyZalost: and food that the chemicals can use to make more of themselves using the energy available to them
(19:37:26) SpookyZalost: in a sense, DNA is it's self a life form
(19:37:38) SpookyZalost: albeit the most complex and basic life form known all at once.
(19:38:18) brian54[SEMINAR]: i think i get that :)
(19:38:33) SpookyZalost: so until we can reach out to those places that have a high chance for harboring life we can only wait as planned missions reach out to discover the truths in these places.
and unlock the secrets to how we all came to be on this tiny ark floating in a sea of endless possibility
(19:38:56) SpookyZalost: one thing is for certain though, life is a tenacious thing, and once it gets going, it's hard to stop.
(19:39:14) SpookyZalost: I would like to take the remaining time to answer any questions you guys may have about the topic discussed.

Q&A session:

(19:39:26) brian54[SEMINAR]: thanks :)
(19:39:40) Ceafus88: Interesting
(19:39:44) brian54[SEMINAR]: well simple and omplex dna
(19:40:05) brian54[SEMINAR]: i assume u mean there arnt that many different amino acids
(19:40:13) SpookyZalost: oh there are
(19:40:16) brian54[SEMINAR]: but there in this long complex chain right :)
(19:40:17) SpookyZalost: DNA is just one of them
(19:40:33) SpookyZalost: you've got RNA, TNA, DNA, PNA, and a few others that were discovered as fossils
(19:40:39) brian54[SEMINAR]: ok so go on what did u mean by both simple and complex ?
(19:41:04) tc: nope no questions, quite fascinating
(19:41:11) SpookyZalost: well DNA is simple in that the chemicals it's made of and it's growth process is relatively simple compared to larger things, but it's complex in that how it combines leads to almost everything we know
(19:41:27) brian54[SEMINAR]: ok i see thanks
(19:41:43) brian54[SEMINAR]: do u recall the old star trek episode, the one with the rock creatures
(19:41:50) SpookyZalost: yes?
(19:41:52) brian54[SEMINAR]: where they suggested life was based on silicon ?
(19:41:58) SpookyZalost: entirely possble
(19:42:06) SpookyZalost: in fact silicon is the second most likely element after carbon
(19:42:09) brian54[SEMINAR]: rather than carbon
(19:42:13) brian54[SEMINAR]: ya ?
(19:42:20) SpookyZalost: though the environments required for it would be hellish compared to earth
(19:42:22) brian54[SEMINAR]: ya i always liked that episode
(19:42:31) brian54[SEMINAR]: indeed !
(19:42:45) SpookyZalost: hot worlds with thick atmospheres, high in vulcanism, and probably containing silicon bonded molecules with silane as a solvent
(19:42:45) brian54[SEMINAR]: u know what i really found interesting
(19:42:49) SpookyZalost: silan is a silicon variant of methane
(19:42:57) brian54[SEMINAR]: when u talked about the different forces like gravity
(19:43:12) brian54[SEMINAR]: and how this would effect the evolutionary process of life
(19:43:14) SpookyZalost: yes?
(19:43:17) brian54[SEMINAR]: i loved that part :)
(19:43:39) brian54[SEMINAR]: there could be all sorts of possibilities
(19:43:54) SpookyZalost: well we know this works simply by studying the way life grows in labs in orbit of our planet as well as in synthesized gravity chaimbers
(19:44:03) SpookyZalost: and the effects are quite standard across the board
(19:44:18) brian54[SEMINAR]: but one thing i wanted to ask u about because this was a bit before your time but u may know this :)
(19:44:31) brian54[SEMINAR]: do u recall when we first landed on Mars
(19:44:38) brian54[SEMINAR]: and they took soil samples and such
(19:44:41) SpookyZalost: the probes you mean?
(19:44:42) SpookyZalost: yeah
(19:44:58) brian54[SEMINAR]: there was this big debate about whther they found evidence of life or not
(19:45:06) brian54[SEMINAR]: and it was like about a 50 / 50 thing
(19:45:16) brian54[SEMINAR]: what was the end determiantion of that if u know ?
(19:45:35) brian54[SEMINAR]: it was a very ehated debate that went on a long time
(19:45:38) brian54[SEMINAR]: heated
(19:45:51) SpookyZalost: that was proven to be a false reading later on, however if there is life on mars, it's most likely deep underground where water is most likely still liquid.
I mean we have subterranean lakes deep under earth's surface.
(19:45:59) brian54[SEMINAR]: and i think what they were mostly trying to suggest did life exist on mars at one point in the past
(19:46:05) brian54[SEMINAR]: not that it was a current thing see
(19:46:09) SpookyZalost: yes, there's other reasons for that
(19:46:22) brian54[SEMINAR]: ya that could be an entuire semianr initself !
(19:46:35) god_donut: very nice, great job leo
(19:46:39) god_donut: i will bbiab
(19:46:40) ChatBot: god_donut is now afk
(19:46:40) SpookyZalost: it's a heated debate about a mars rock they found in Antarctica for example which was ancient but contained what might possibly be fossils of ancient micro-organisms.
(19:46:51) brian54[SEMINAR]: ah
(19:46:59) brian54[SEMINAR]: an also whther there was water at one time
(19:47:00) SpookyZalost: but mars certainly had the potential for life early on in it's past
(19:47:09) brian54[SEMINAR]: but i guess the water is sorta done deal right ?
(19:47:14) SpookyZalost: and there was liquid water on mars's surface millions of years ago
(19:47:23) SpookyZalost: there's clear evidence of this
(19:47:31) brian54[SEMINAR]: that thee was evidence there was water there one time ya
(19:47:35) brian54[SEMINAR]: ya love this :)
(19:47:54) SpookyZalost: but mars never developed an electromagnetic field so the sun's solar wind stripped mars of it's then thick atmosphere and the planet's surface became uninhabitable and unsafe for complex molecules to remain stable.
(19:48:05) brian54[SEMINAR]: i never heard actually of thios mars rock
(19:48:24) brian54[SEMINAR]: are u talking about our anartica ?
(19:48:27) SpookyZalost: thus if there is life on mars, it's likely deep below the ground.
(19:48:30) SpookyZalost: brian: yes
(19:48:34) brian54[SEMINAR]: oh
(19:48:39) brian54[SEMINAR]: how did it get there ?
(19:48:45) SpookyZalost: there's only one Antarctica brian :)
(19:48:50) brian54[SEMINAR]: ya
(19:48:56) brian54[SEMINAR]: how did it get there from mars ?
(19:49:14) SpookyZalost: it's likely that the rock ended up there after a large collision ejected rock from mars's surface and that rock got sent out of mars's gravity field, then entered earth's atmosphere and impacted the planet
(19:49:31) brian54[SEMINAR]: oh i see
(19:49:40) brian54[SEMINAR]: so maybe a meteoite struck mars ?
(19:49:46) brian54[SEMINAR]: and cause an explosion ?
(19:49:49) SpookyZalost: this is also how we know mars had an atmosphere that was thicker and slightly different in in composition to today
(19:50:01) SpookyZalost: because they found trace elements from the rock's time on mars that aren't there now.
(19:50:12) brian54[SEMINAR]: ya
(19:50:20) SpookyZalost: brian: you've got it
(19:50:31) brian54[SEMINAR]: ok i think thats all the Q i have for now :)
(19:50:35) brian54[SEMINAR]: anyone else ?
(19:50:47) SpookyZalost: mars is much smaller than earth, about 1/4 the size actually so the force required to escape it's gravity field is far less than our planet's
(19:50:58) SpookyZalost: does anyone else have a question?
(19:51:08) brian54[SEMINAR] applauds sz :)
(19:51:16) ChatBot: brian54[SEMINAR]'s status is now seminar.
(19:51:25) ChatBot: brian54[SEMINAR][seminar]'s status is now rset.
(19:51:30) Ceafus88: Nope, thanks for the seminar
(19:51:33) brian54[SEMINAR][rset]: hmm
(19:52:02) ChatBot: brian54[rset]'s SEMINAR status has been reset
(19:52:07) SpookyZalost: that's about all I know on the topic :P I can go into more detail on stuff but that's astrobiology in a nutshell :)
(19:52:11) ChatBot: brian54's rset status has been reset
(19:52:16) brian54: took some work LOL
(19:52:21) SpookyZalost: a lot of theory based on known facts and science :)
(19:52:31) brian54: ya nice semiar there
(19:52:39) SpookyZalost: and a lot of exciting prospects to be determined in coming years
(19:52:39) tc: but a very interesting topic
(19:52:40) brian54: and our furst ever back to back seminars !
(19:52:49) brian54: 2 nights ina row
(19:52:57) SpookyZalost: TC: you can kinda see why I want to do that with my life :P
(19:53:04) tc: one that's at it's infancy stage, that's quite exciting actually
(19:53:13) tc: the pioneers in that field
(19:53:19) SpookyZalost: exactly :D
(19:53:39) brian54: oh
(19:53:51) tc: and even though it's quite a young field there is more opportunity in it than just theory
(19:53:52) brian54: someone
(19:54:01) brian54: make sure u record this for the forums

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 Itwas a great seminar as i expected it would be, and I enjoyed it

attendance for this seminar = 6

Thanks to leo for the great job he did as quest speaker..

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