Space colonization

[Nemesis]

What's all the fuzz about raising some funny flag on the moon 50 years ago? It was the cold war, it was about military domination of the orbit. Most of space exploration is rooted in military aspirations of some funny "superpowers"

What would the average Joe win from some funny men on funny Mars? Nothing. Funny gamez of the funny elite who fucked up the natural life-basis of mankind on Earth

[crandles]

This may mean that the tectonic catastrophe on Venus occurred relatively recently.

Why are you assuming that there was a "tectonic catastrophe" on Venus? I don't see why I should assume anything other than this is your hobby horse for which you have zero evidence.

Thick atmosphere does sound unusual but given that

The early Earth during the Hadean eon is believed by most scientists to have had a Venus-like atmosphere, with roughly 100 bar of CO2

https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Evolution

perhaps it is not that surprising.

[ArcticMelt1]

This may mean that the tectonic catastrophe on Venus occurred relatively recently.

Why are you assuming that there was a "tectonic catastrophe" on Venus?

Because Venus is much closer to the Sun than the Earth. In addition, there is no magnetic field on it. In this regard, it should lose the atmosphere much faster than the Earth.

The fact that Venus has a superdense atmosphere compared to the Earth is a very mysterious fact.

Recent studies suggest that in the past, ocean and life could exist on Venus.

https://www.nasa.gov/feature/goddard/2016/nasa-climate-modeling-suggests-venus-may-have-been-habitable

Venus may have had a shallow liquid-water ocean and habitable surface temperatures for up to 2 billion years of its early history, according to computer modeling of the planet’s ancient climate by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York.

Previous studies have shown that how fast a planet spins on its axis affects whether it has a habitable climate. A day on Venus is 117 Earth days. Until recently, it was assumed that a thick atmosphere like that of modern Venus was required for the planet to have today’s slow rotation rate. However, newer research has shown that a thin atmosphere like that of modern Earth could have produced the same result. That means an ancient Venus with an Earth-like atmosphere could have had the same rotation rate it has today.

In general, current knowledge suggests the similarity of the geology of Venus and the Earth.

https://www.lpi.usra.edu/publications/slidesets/venus/slide_40.html

This slide shows a comparison of rift zones on the three largest terrestrial planets. The Venus SAR image is of Devana Chasma as it runs from Theia Mons in the north to Phoebe Regio in the south. On Earth, digital topography and bathymetry are used to create this shaded relief portrayal of the East African rift system as it runs north and intersects at the Afar triple junction with the oceanic spreading centers of the Red Sea and the Gulf of Aden. The Mars image is a Viking image mosaic of the Valles Marineris system.

Liquid water is needed to form rift tectonics.

But these are all hypotheses, because precisely the direct drilling of its surface can tell exactly about the geological past of Venus. Unfortunately, such a project will be extremely expensive and difficult. I fear that humanity will learn the terrible truth about Venus’s past too late to draw conclusions about the future of the Earth.

[ArcticMelt1]

The early Earth during the Hadean eon is believed by most scientists to have had a Venus-like atmosphere, with roughly 100 bar of CO2

https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Evolution

perhaps it is not that surprising.

There is an opposite opinion.

https://www.nature.com/articles/ngeo2713

Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels

How the Earth stayed warm several billion years ago when the Sun was considerably fainter is the long-standing problem of the ‘faint young Sun paradox’. Because of negligible1 O2 and only moderate CO2 levels2 in the Archaean atmosphere, methane has been invoked as an auxiliary greenhouse gas3. Alternatively, pressure broadening in a thicker atmosphere with a N2 partial pressure around 1.6–2.4 bar could have enhanced the greenhouse effect4. But fossilized raindrop imprints indicate that air pressure 2.7 billion years ago (Gyr) was below twice modern levels and probably below 1.1 bar, precluding such pressure enhancement5. This result is supported by nitrogen and argon isotope studies of fluid inclusions in 3.0–3.5 Gyr rocks6. Here, we calculate absolute Archaean barometric pressure using the size distribution of gas bubbles in basaltic lava flows that solidified at sea level ∼2.7 Gyr in the Pilbara Craton, Australia. Our data indicate a surprisingly low surface atmospheric pressure of Patm = 0.23 ± 0.23 (2σ) bar, and combined with previous studies suggests ∼0.5 bar as an upper limit to late Archaean Patm. The result implies that the thin atmosphere was rich in auxiliary greenhouse gases and that Patm fluctuated over geologic time to a previously unrecognized extent.

[GoSouthYoungins]

I can't believe there is genuine discussion on here about which other planet we could live on...as if it is a serious possibility. I understand as a purely theoretical sort of thing it might be fun to discuss, but colonizing another planet has about a 0.1% chance in any of our lifetimes. Mars, Venus, and the Moon are about 1000x less hospitable than Antarctica or Mount Everest or the Mariana Trench. Those who believe the Elon Musk line that "living on Mars is the easy part" are full blown delusional.

It took humans 65 years to get from the first powered flight to the "moon landing". In the 50 years since, we have regressed (or more likely no one ever went to the moon, but the point is simiilar). The idea that in the next 115 years we will not only but a person on other planets but colonize them is insane and totally unsupported by evidence.

People can't even live in enclosed systems here on earth for a sustained period of time! The best example being Biosphere 2, which is located in a place as conducive to easy living as possible (Oracle, AZ is prime from low tech passive structures). And they spent 4 years and hundreds of millions of dollars building the place. AND YET nobody is running closed-system experiments directly involving humans and they have not been for a quarter century because...it basically doesn't work.  As for the "Mars analog habitats", they are a total joke unless you happen to believe that Nunavut or Utah are analogous to Mars.

[crandles]

The early Earth during the Hadean eon is believed by most scientists to have had a Venus-like atmosphere, with roughly 100 bar of CO2

https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Evolution

perhaps it is not that surprising.

There is an opposite opinion.

https://www.nature.com/articles/ngeo2713

Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels

How the Earth stayed warm several billion years ago when the Sun was considerably fainter is the long-standing problem of the ‘faint young Sun paradox’. Because of negligible1 O2 and only moderate CO2 levels2 in the Archaean atmosphere, methane has been invoked as an auxiliary greenhouse gas3. Alternatively, pressure broadening in a thicker atmosphere with a N2 partial pressure around 1.6–2.4 bar could have enhanced the greenhouse effect4. But fossilized raindrop imprints indicate that air pressure 2.7 billion years ago (Gyr) was below twice modern levels and probably below 1.1 bar, precluding such pressure enhancement5. This result is supported by nitrogen and argon isotope studies of fluid inclusions in 3.0–3.5 Gyr rocks6. Here, we calculate absolute Archaean barometric pressure using the size distribution of gas bubbles in basaltic lava flows that solidified at sea level ∼2.7 Gyr in the Pilbara Craton, Australia. Our data indicate a surprisingly low surface atmospheric pressure of Patm = 0.23 ± 0.23 (2σ) bar, and combined with previous studies suggests ∼0.5 bar as an upper limit to late Archaean Patm. The result implies that the thin atmosphere was rich in auxiliary greenhouse gases and that Patm fluctuated over geologic time to a previously unrecognized extent.

>There is an opposite opinion.

My quote clearly suggest that it is "believed by most scientists" and therefore clearly allows the possibility of other opinions. However my quote was clearly about Hadean eon (4-4.6bn years ago) and you try to argue with something from 2.7 billion years ago which is towards end of Archean Eon. So it doesn't exactly refute what I said, does it.

[ArcticMelt1]

As I understand it, it is only theoretically possible to judge the atmospheric pressure 4-4.5 billion years ago - sedimentary rocks with like age on Earth are simply not preserved. In this regard, recent studies of rocks with an age of about 3 billion years completely negate this opinion of the "majority". If 4 billion years ago there were very high atmospheric pressure, then it should have been higher than today and 3 billion years ago. However, recent studies do not confirm this.

[ArcticMelt1]

Actually, Wikipedia provides a large number of alternatives to the superdense atmosphere of the ancient Earth.

https://en.wikipedia.org/wiki/Faint_young_Sun_paradox

The faint young Sun paradox or faint young Sun problem describes the apparent contradiction between observations of liquid water early in Earth's history and the astrophysical expectation that the Sun's output would be only 70 percent as intense during that epoch as it is during the modern epoch.

Greenhouse hypothesis[edit]
When it first formed, Earth's atmosphere may have contained more greenhouse gases. Carbon dioxide concentrations may have been higher, with estimated partial pressure as large as 1,000 kPa (10 bar), because there was no bacterial photosynthesis to convert the CO2 gas to organic carbon and gaseous oxygen. Methane, a very active greenhouse gas that reacts with oxygen to produce carbon dioxide and water vapor, may have been more prevalent as well, with a mixing ratio of 10−4 (100 parts per million by volume).[9][10]

Based on a study of geological sulfur isotopes, in 2009 a group of scientists including Yuichiro Ueno from the Tokyo Institute of Technology proposed that carbonyl sulfide (OCS) was present in the Archean atmosphere. Carbonyl sulfide is an efficient greenhouse gas and the scientists estimate that the additional greenhouse effect would have been sufficient to prevent Earth from freezing over.[11]

Based on an "analysis of nitrogen and argon isotopes in fluid inclusions trapped in 3.0- to 3.5-billion-year-old hydrothermal quartz" a 2013 paper concludes that "dinitrogen did not play a significant role in the thermal budget of the ancient Earth and that the Archean partial pressure of CO2 was probably lower than 0.7 bar".[12] Burgess, one of the authors states "The amount of nitrogen in the atmosphere was too low to enhance the greenhouse effect of carbon dioxide sufficiently to warm the planet. However, our results did give a higher than expected pressure reading for carbon dioxide – at odds with the estimates based on fossil soils – which could be high enough to counteract the effects of the faint young Sun and will require further investigation."[13] Also, in 2012-2016 the research by S.M. Som, based on the analysis of raindrop impressions and air bubbles trapped in ancient lavas, have further indicated a low atmospheric pressure below 1.1 bar and probably as low as 0.23 bar during an epoch 2.7 bn years from present.[14]

Following the initial accretion of the continents after about 1 billion years,[15] geo-botanist Heinrich Walter and others contend that a non-biological version of the carbon cycle provided a negative temperature feedback. The carbon dioxide in the atmosphere dissolved in liquid water and combined with metal ions derived from silicate weathering to produce carbonates. During ice age periods, this part of the cycle would shut down. Volcanic carbon emissions would then restart a warming cycle due to the greenhouse effect.[16][17]

According to the Snowball Earth hypothesis, there may have been a number of periods when Earth's oceans froze over completely. The most recent such period may have been about 630 million years ago.[18] Afterwards, the Cambrian explosion of new multicellular life forms started.

Greater radiogenic heat[edit]

The radiogenic heat from the decay of 4 isotopes affecting Earth's internal heat budget over time: 40K (yellow), 235U (red), 238U (green) and 232Th (violet). In the past the contribution from 40K and 235U was much higher and thus the overall radiogenic heat output was higher.
In the past, the geothermal release of decay heat, emitted from the decay of the isotopes potassium-40, uranium-235 and uranium-238 was considerably greater than it is today.[19] The figure to the right shows that the isotope ratio between uranium-238 and uranium-235 was also considerably different than it is today, with the ratio essentially equivalent to that of modern low-enriched uranium. Therefore, natural uranium ore bodies, if present, would have been capable of supporting natural nuclear fission reactors with common light water as its moderator. Any attempts to explain the paradox must therefore factor in both radiogenic contributions, both from decay heat and from any potential natural nuclear fission reactors.

The primary mechanism for Earth warming by radiogenic heat is not the direct heating (which contribute less than 0.1% to the total heat input even of early Earth) but rather the establishment of the high geothermal gradient of the crust, resulting in greater out-gassing rate and therefore the higher concentration of greenhouse gases in early Earth atmosphere. Additionally, a hotter deep crust would limit the water absorption by crustal minerals, resulting in a smaller amount of high-albedo land protruding from the early oceans, causing more solar energy to be absorbed.


Greater tidal heating[edit]
The Moon was much closer to Earth billions of years ago,[20] and therefore produced considerably more tidal heating.[21]

Alternatives[edit]

Phanerozoic Climate Change
A minority view, propounded by the Israeli-American physicist Nir Shaviv, uses climatological influences of solar wind, combined with a hypothesis of Danish physicist Henrik Svensmark for a cooling effect of cosmic rays, to explain the paradox.[22] According to Shaviv, the early Sun had emitted a stronger solar wind that produced a protective effect against cosmic rays. In that early age, a moderate greenhouse effect comparable to today's would have been sufficient to explain an ice-free Earth. Evidence for a more active early Sun has been found in meteorites.[23]

The temperature minimum around 2.4 billion years goes along with a cosmic ray flux modulation by a variable star formation rate in the Milky Way. The reduced solar impact later results in a stronger impact of cosmic ray flux (CRF), which is hypothesized to lead to a relationship with climatological variations.

An alternative model of solar evolution may explain the faint young Sun paradox. In this model, the early Sun underwent an extended period of higher solar wind output. This caused a mass loss from the Sun on the order of 5−10 percent over its lifetime, resulting in a more consistent level of solar luminosity (as the early Sun had more mass, resulting in more energy output than was predicted). In order to explain the warm conditions in the Archean era, this mass loss must have occurred over an interval of about one billion years. However, records of ion implantation from meteorites and lunar samples show that the elevated rate of solar wind flux only lasted for a period of 0.1 billion years. Observations of the young Sun-like star π1 Ursae Majoris matches this rate of decline in the stellar wind output, suggesting that a higher mass loss rate can not by itself resolve the paradox.[24]

Examination of Archaean sediments appears inconsistent with the hypothesis of high greenhouse concentrations. Instead, the moderate temperature range may be explained by a lower surface albedo brought about by less continental area and the "lack of biologically induced cloud condensation nuclei". This would have led to increased absorption of solar energy, thereby compensating for the lower solar output.[25]

On Mars[edit]
Usually, the faint young Sun paradox is framed in terms of Earth's paleoclimate. However, the issue also appears in the context of the climate on ancient Mars, where apparently liquid water was present, in significant amounts (hydrological cycle, lakes, rivers, rain, possibly seas and oceans), billions of years ago. Subsequently, significant liquid water disappeared from the surface of Mars. Presently, the surface of Mars is cold and dry. The variable solar output, assuming nothing else changed, would imply colder (and drier) conditions on Mars in the ancient past than they are today, apparently contrary to the empirical evidence from Mars exploration that suggest the wetter and milder past. An explanation of the faint young Sun paradox that could simultaneously account for the observations might be that the Sun shed mass through the solar wind, though sufficient rate of mass shedding is so far unsupported by stellar observations and models.[26]

An alternative possible explanation posits intermittent bursts of powerful greenhouse gases, like methane. Carbon dioxide alone, even at a pressure far higher than the current one, cannot explain temperatures required for presence of liquid water on early Mars.[27]

[ArcticMelt1]

There is also a hypothesis that a ocean on ancient Earth was formed as a result of meteorite bombardment.

https://en.wikipedia.org/wiki/Cool_early_Earth

Cool early Earth

The cool early Earth (CEE) theory posits that for part of the Hadean geological eon, at the beginning of Earth's history, it had a modest influx of bolides and a cool climate, allowing the presence of liquid water. This would have been after the extreme conditions of Earth's earliest history between 4.6 and 4.4 billion years (Ga) ago, but before the Late Heavy Bombardment of 4.1 to 3.8 Ga ago. In 2002 John Valley et al argued that detrital zircons found in Western Australia, dating to 4.0–4.4 Ga ago, were formed at relatively low temperatures, that meteorite impacts may have been less frequent than previously thought, and that Earth may have gone through long periods when liquid oceans and life were possible.[1]

In 2016 Gavin Kenny et al. replied to suggestions that zircons were formed by melting during tectonic subduction at plate boundaries, and argued that at least some of them were formed by meteorite impacts.[2]

[Sigmetnow]

Suggestions for further, mostly science-based, reading/viewing:

NatGeo‘s Mars series, now in season two. Much of the show is interviews with actual scientists and Mars researchers, and activists trying to save earth today.  The fictional Mars drama is good, but I wish they had knowledgeable consultants to guide their medical depictions.
https://www.nationalgeographic.com/tv/mars/

Seveneves, by Neal Stephenson
Excerpt:

“We will have to do both,” the president said. “Go into space, and underground. Obviously the latter is easier.”
“Yes.”
“We can get to work building underground bunkers for . . .” and she caught herself before saying something impolitic. “For people to take refuge in.”
Doob didn’t say anything.
The chairman of the Joint Chiefs of Staff said, “Dr. Harris, I’m an old logistics guy. I deal in stuff. How much stuff do we need to get underground? How many sacks of potatoes and rolls of toilet paper per occupant? I guess what I’m asking is, just how long is the Hard Rain going to last?”
Doob said, “My best estimate is that it will last somewhere between five thousand and ten thousand years.” …

The SpaceX Mars plan.
Musk:  “It will be like Shackleton’s ad for Antarctic explorers: ‘Difficult, dangerous, a good chance you’ll die, excitement for those who survive.’ That kind of thing.
https://www.theguardian.com/technology/2018/mar/11/elon-musk-colonise-mars-third-world-war

https://www.inverse.com/article/51273-spacex-elon-musk-reveals-when-first-mars-colony-will-take-shape

http://www.visiontimes.com/2018/12/09/mars-colonization-comes-with-jobs-and-finance-options-for-tickets.html

[Nemesis]

" “We can get to work building underground bunkers for . . .” and she caught herself before saying something impolitic. “For people to take refuge in.”

What kind of people will take refuge in underground bunkers? Sure, the money elite (and some servants):

[Nemesis]

Well then, good luck to these folks trying to escape from their predicament...

"... Oh, I see dreams
I see visions
Images I don't understand
I see Goya's
Paranoias..."

[kassy]

Now there are many works that suggest the existence of life and oceans on Venus in the past. It cannot be ruled out that there once was also a rational civilization, which destroyed both itself and the planet.

The transition to Venus´ Greenhouse climate is thought to have happened 4 billion years ago. It happened because the sun increases in luminosity year over year slowly warming up the planet.

And then it got hotter. Non need for tectonic catastrophes there and the chance of a rational civilization is zero.

You have a billion year time frame and it took half a billion years from first live to evolving photosynthesis. On Earth it took another billion years before the Great Oxygenation Event which allowed multicellular life to thrive.

Crandles in #43 shows why an event in the range you obsess about is not even possible.

(I am still undecided whether Alderaan would have hit 100C... )

PS: thanks NeilT for some good points on the moon.

 

[Sigmetnow]

...
The SpaceX Mars plan.
Musk:  “It will be like Shackleton’s ad for Antarctic explorers: ‘Difficult, dangerous, a good chance you’ll die, excitement for those who survive.’ That kind of thing.
https://www.theguardian.com/technology/2018/mar/11/elon-musk-colonise-mars-third-world-war

https://www.inverse.com/article/51273-spacex-elon-musk-reveals-when-first-mars-colony-will-take-shape

http://www.visiontimes.com/2018/12/09/mars-colonization-comes-with-jobs-and-finance-options-for-tickets.html

In answer to the the poll question:  Musk envisions eventually 100 persons per ship — with 1,000 ships making the trip during the Earth-Mars rendezvous period every two years.  He figures a Mars population of one million is the minimum to be self-sustaining.

Musk had teased some changes to the most recent Starship design....  But last night he shocked us with new information on Twitter, and we now have pictures of the prototype Starship being built in Texas (the diameter of the real thing, but shorter in length)  which should begin “test hop” flights by next spring!

Elon Musk: I will do a full technical presentation of Starship after the test vehicle we’re building in Texas flies, so hopefully March/April
https://twitter.com/elonmusk/status/1076608579652616192

<< Wait... March/April 2019!? This is much sooner than expected, yes!?

EM:  Yes
https://twitter.com/elonmusk/status/1076608854643814400

SpaceX CEO Elon Musk says Starship (BFS) hop tests could start in early 2019
https://www.teslarati.com/spacex-ceo-elon-musk-starship-bfs-hop-tests-early-2019/

[sesyf]

Weeeelll... moon dust just got a lot more dangerous...

https://agu.confex.com/agu/fm18/meetingapp.cgi/Paper/440491

From New Scientist:

To estimate how many radicals would be produced in humans after exposure to lunar dust, Donald Hendrix at Stony Brook University, New York, and his colleagues took dust from two iron-rich minerals – olivine and augite – found on the moon, and soaked it in a liquid that simulates human lung fluid.

After 15 minutes, the two minerals had released about nine times more hydroxyl radicals per litre of fluid than quartz dust, which is highly toxic.

I do suspect that as we are adapted to our environment the very technical environment we would be forced to live in Moon and Mars (and also the gravity is weaker among other things) would be very problematic on many levels...

[Archimid]

and also the gravity is weaker among other things

I wonder what evolutionary changes are required for humans to be perfectly adapted to a g/3 environment. Taller humans? Shorter humans? More or less dense humans? Would the proportions of extremities change to optimize movement? In a few thousand years we will know if left to nature.
Technologies like gene editing might hasten that process considerably.

Then, whether by way of nature or by way technology, we have to ask ourselves, are these Homo Sapiens? I don't think so. Then humans can't colonize the universe because H. sapiens will eventually evolve to match their environment. However, humans can spread life to an otherwise lifeless solar system. Maybe,eventually the stars.

But before we do that, we must solve climate change.

[ArcticMelt1]

In answer to the the poll question:  Musk envisions eventually 100 persons per ship — with 1,000 ships making the trip during the Earth-Mars rendezvous period every two years.  He figures a Mars population of one million is the minimum to be self-sustaining.

Good news. It is hoped that by the end of the 21st century millions of people will live and work in space. This will be a good insurance against disasters on Earth.

[Nemesis]

Trump surely is on the side of Elon Musk, the saviour of the world, when it comes to colonialization of Mars:

" 18.6.2018 - Trump’s Space Force Is Almost a Real Thing
The president on Monday announced he has directed the Department of Defense to create a sixth branch of the military

... While contemplating the infinite frontier during a meeting with the National Space Council, the president announced the creation of the “Space Force,” a new branch of the military that will be tasked with handling extraterrestrial affairs. “I am hereby directing the Department of Defense and Pentagon to immediately begin the process necessary to establish a Space Force as the sixth branch of the armed forces,” Trump said...

Trump also continued to tout the prospect of a mission to Mars, which he is more than happy to leave in the hands of the Elon Musks of the world – or at least of America...

... Trump signed White House Space Policy Directive 1, which called for the United States to work with the private sector in an effort to put more men on the moon and, eventually, Mars. “The directive I am signing today will refocus America’s space program on human exploration and discovery,” Trump said at the time. “It marks a first step in returning American astronauts to the Moon for the first time since 1972, for long-term exploration and use. This time, we will not only plant our flag and leave our footprints – we will establish a foundation for an eventual mission to Mars, and perhaps someday, to many worlds beyond."

https://www.rollingstone.com/politics/politics-news/trumps-space-force-is-almost-a-real-thing-665983/

Also quite interesting:

" Trump presidency 'opens door' to planet-hacking geoengineer experiments

As geoengineer advocates enter Trump administration, plans advance to spray sun-reflecting chemicals into atmosphere...

Within Republican ranks, former House speaker and Trump confidant Newt Gingrich was one of the first to start publicly advocating for geoengineering.

Within Republican ranks, former House speaker and Trump confidant Newt Gingrich was one of the first to start publicly advocating for geoengineering.

“Geoengineering holds forth the promise of addressing global warming concerns for just a few billion dollars a year,” he said in 2008, before helping launch a geoengineering unit while he ran the right-wing think tank American Economic Enterprise. “We would have an option to address global warming by rewarding scientific innovation. Bring on American ingenuity. Stop the green pig.”

https://www.theguardian.com/environment/true-north/2017/mar/27/trump-presidency-opens-door-to-planet-hacking-geoengineer-experiments

See also:

https://www.theguardian.com/environment/2017/oct/14/geoengineering-is-not-a-quick-fix-for-climate-change-experts-warn-trump

Sure, Trump denies fossil fuel induced climate heating publically (being heavily supported by the fossil fuel industry, who denied fossil fuel induced heating for many decades despite their very own contrary scientific findings too^^), so it makes sense to quit the Paris agreement and to bet on technical solutions for *none-existing* fossil fuel induced climate heating while striving for Mars Denying fossil fuel induced climate heating despite one's very own scientific findings? Well, that's a well known strategy of the fossil fuel industry, isn't it? Yes, it is and Trump's presidency fits perfectly into that scheme. And at the same time parts of the fossil fuel industry admit fossil fuel induced climate heating is real. Supporting both sides of the coin to maintain overall control is a well known strategy as old as Empire.

[Nemesis]

What's going on behind all the smoke and mirrors?

"Eisenhower warns us of the military industrial complex."



There is the president of the US (like Eisenhower or Bush or Reagan, Clinton, Obama, Trump and what have you) and then there is the Pentagon (and the CIA and the NSA) and it's military force. What's the engine of the military industrial complex? Fossil fuel delivered by the fossil fuel industry (who knows the science about fossil fuel induced climate heating and who supported Trump). Remember Dick Cheney (weapons industry)? Remember Rex Tillerson (oil industry resp Exxon)?

Space colonialization? Star wars? Geo- resp climate engineering since Svante Arrhenius? Fossil fueled geopolitics? Admitting to fossil fueled climate heating, then denying it? Signing to Paris, then resigning from Paris? Many sides, but one coin.

[Tom_Mazanec]

When I was a kid, I fervently believed we would live like Star Trek some day soon. Maybe I am just a crotchety old man now, but I am dubious that it will work. I still follow sites like Centauri Dreams and read SF till it is coming out of my ears, and I still hope we will get into the Solar System somehow, but 99.9999% of the species will still be earthbound even if that comes off.

[GoSouthYoungins]

What is the least habitable place that has been (at least semi) self-sustainably colonized?

I think La Paz in Bolivia at about 3,600 meters is. If anyone thinks there is a genuine established settlement in a harsher place, please do tell.

(Inuit settlements are probably more severe, but are functionally totally different because the people rely/relied on whaling and other ocean food sources.)

Anyways, La Paz is about 100 times more habitable than Antarctica.  The total amount of food ever grown in Antarctica is a joke.

And yet, Antarctica is 100 times more habitable than the moon or mars or a space dinghy.

Sustaining life in a space dinghy, or on another planets is hundreds of years off (if it is even possible).  Most cells in the human body are not human cells. And we NEED these cells. They come from our environment and without them the vigor of a human diminishes toward zero. There are countless other examples of why humans need the earth...gravity, magnetic sphere, etc. And of course, there are all sorts of things yet to be discovered.

Leaving earth is not possible (maybe in will be in a few centuries, but I doubt it). In the last 50 years, human space travel has regressed and no person has left low earth orbit in the last 47 years. (Personally I think that anyone ever did is highly questionable, and the Nixon administration lying to a gullible public is more probable.)


Additionally, the premise that leaving our planet isn't possible is the only plausible answer to Fermi's paradox...

Alien intelligent life, where ever in the universe it has ever developed, has never been able to travel very far from its origin.

[GoSouthYoungins]

I wonder what evolutionary changes are required for humans to be perfectly adapted to a g/3 environment. Taller humans? Shorter humans? More or less dense humans? Would the proportions of extremities change to optimize movement? In a few thousand years we will know if left to nature.

Sorry. That isn't how evolution works.

[Tom_Mazanec]

Additionally, the premise that leaving our planet isn't possible is the only plausible answer to Fermi's paradox...


No, GoSouthYoungins, there are other plausible answers. My personal favorite is that it is hyperastronomically improbable that a protobacterium capable of evolving into higher life could form  spontaneously.

[Neven]

Tom, is this an invitation for a discussion about creation?

[Tom_Mazanec]

neven:
no.
I specifically said this is very unlikely as an Astronomy BS from what I learned in my courses. I did not mention Creationism.

EDIT: To be more detailed, I know Darwinian Evolution is a very positive force (well, it's not a "force" in the physical sense, but you know what I mean). But it has to get started. To get started you need an organism with a genetic code that can reproduce, pass characteristics to its descendants, but on occasion change a characteristic in a way that is inherited itself. That is quite an organized structure. That is one explanation for the Fermi Paradox. There are others...development of macroscopic life may be very difficult...the Earth spent most of its habitable span with life you need a microscope to see, and other planets may not have that much longer windows (for example, red dwarfs are on the Main Sequence longer than Sol, but their planets probably quickly get tidal locked). Or maybe space colonization is possible in theory for a sufficiently advanced technology, but all the "passive" species live millions of years with a sustainable technology and all the "aggressive" ones self-destruct before colonizing space.

PS I am not a biologist. If someone is please help me understand how an evolvable organism "easily" arises before it can start evolving.

[Neven]

neven:
no.
I specifically said this is very unlikely as an Astronomy BS from what I learned in my courses. I did not mention Creationism.

OK, thanks. I misinterpreted.

[kassy]

In a recent talk Erik Verlinde stressed that there is so much about the universe that we don´t know because we only started gathering data a short while ago.

Not too long ago we still surveyed the night skies with trained observers. They were quite good at estimating the correct brightness of stars but of course they worked much more slowly and they had much smaller telescopes which were all on earth.

Since then we have much better equipment and digital data handling but we tend to forget that all this is recent.

SETI is also pretty recent and they look for radiosignals. How long will we still use those ourselves?

So one simple reason for Fermi's paradox could be that civilizations can miss each other in time (and we don´t have good data on that since we only have 1 point and we could be either early or late).

As for the origins of life from simple cells that happened at least once (and possibly we can find it in multiple places in our own solar system).

As soon as there is a base life tends to re-evolve after disasters.

I also like Jeremy Englands idea of the origin of life as an inevitable outcome of thermodynamics.

TLDR: We think there are no aliens because we have not found anything yet but that should not be surprising if you look at the amount of time spend and technologies used.

The bottleneck might just be evolving the tech to take you to the stars before murdering your home with consumerism...time shall tell.

[oren]

Surely the paradox is easily explained by intelligent civilizations running out of resources on their home planet before they manage the immense resource and energy expenditure associated with leaving the home planet and setting up viable habitats in other locations. In the same vein, these civilizations collapse after a cosmically short period of time, leaving no discernible trace for future astronomers.
As probably will happen to us as well. If all of humanity focused just on this one thing, we could probably make it. But evolution does not lead a species to such a selfless undertaking for the sake of some posterity without expending most resources on procreation and recreation.

[Tom_Mazanec]

In a recent talk Erik Verlinde stressed that there is so much about the universe that we don´t know because we only started gathering data a short while ago.

Not too long ago we still surveyed the night skies with trained observers. They were quite good at estimating the correct brightness of stars but of course they worked much more slowly and they had much smaller telescopes which were all on earth.

Since then we have much better equipment and digital data handling but we tend to forget that all this is recent.

SETI is also pretty recent and they look for radiosignals. How long will we still use those ourselves?

So one simple reason for Fermi's paradox could be that civilizations can miss each other in time (and we don´t have good data on that since we only have 1 point and we could be either early or late).

As for the origins of life from simple cells that happened at least once (and possibly we can find it in multiple places in our own solar system).

As soon as there is a base life tends to re-evolve after disasters.

I also like Jeremy Englands idea of the origin of life as an inevitable outcome of thermodynamics.

TLDR: We think there are no aliens because we have not found anything yet but that should not be surprising if you look at the amount of time spend and technologies used.

The bottleneck might just be evolving the tech to take you to the stars before murdering your home with consumerism...time shall tell.

You are right, we have hardly looked.
But an easy way to communicate throughout the galaxy is to make a von Neumann probe that is also a Bracewell probe. Everything we have sent beyond the orbit of Saturn is a (crude) Bracewell probe...Pioneer plaque, Voyager record, New Horizons message. And the probe would just need the IQ of a bacterium. It just takes one out of 400,000,000,000 star systems over 13,800,000,000 years to do it.
Jeremy Englands...have to look him up.
ADDENDUM: No reason we can't both be right...maybe life almost never gets started and when it does it almost always self-destructs when it evolves intelligent tool users. The second makes almost no difference to the Fermi Paradox if the first is true (though it makes a big difference to us personally).

[Archimid]

I wonder what evolutionary changes are required for humans to be perfectly adapted to a g/3 environment. Taller humans? Shorter humans? More or less dense humans? Would the proportions of extremities change to optimize movement? In a few thousand years we will know if left to nature.

Sorry. That isn't how evolution works.

That is exactly like evolution works. Or do you think humans are not subject to evolution?

[GoSouthYoungins]

I wonder what evolutionary changes are required for humans to be perfectly adapted to a g/3 environment. Taller humans? Shorter humans? More or less dense humans? Would the proportions of extremities change to optimize movement? In a few thousand years we will know if left to nature.

Sorry. That isn't how evolution works.

That is exactly like evolution works. Or do you think humans are not subject to evolution?

The short dense people will have more children survive to child bearing age? The gravity situation is serious but there would be larger threats to life on another planet.

[GoSouthYoungins]

Additionally, the premise that leaving our planet isn't possible is the only plausible answer to Fermi's paradox...


No, GoSouthYoungins, there are other plausible answers. My personal favorite is that it is hyperastronomically improbable that a protobacterium capable of evolving into higher life could form  spontaneously.

You are saying a likely answer is that humanity is a tiny tiny possibility which just happens to be. That is possible, but it is a tiny tiny possibility.

[Paddy]

Eh, when it comes to space colonisation and speculating on what it might do, I feel we're like people at the time of the Wright Brothers speculating about future air travel.  We're just scratching at the surface of what may be achievable in terms of living in space with current projects like the ISS. 

Happy to admit I voted "do not know" on this poll. Far too many unknowns still with regards to space colonisation's potential challenges.

[Archimid]

The short dense people will have more children survive to child bearing age? The gravity situation is serious but there would be larger threats to life on another planet.

That is simple Darwinian evolution. Evolution happens at much deeper levels than just reproduction of the fittest. Or do you believe you are such a superior being that you are above evolution?

[ArcticMelt2]

There are only a few hours left until the first attempt to launch Starlink satellites again. If successful, the launch of the first 60 satellites company SpaceX will earn many billions to create on Mars a safe haven in case of greenhouse and tectonic catastrophe on Earth

broadcast launch

[ArcticMelt2]

According to the forecasts of Starlink will make cheaper satellite broadband front transcontinental submarine cables.

For an example:

https://en.wikipedia.org/wiki/Unity_(cable_system)

Unity comprises a 10,000 km linear cable system with a "multi-terabit" capacity of up to 7.68 Tbit/s.[4] Construction of the cable was funded by a consortium formed in February 2008 comprising Bharti Airtel, Global Transit, Google, KDDI Corporation, Pacnet and SingTel.[4] Unity's installation cost around US$300 million, and its completion increased Trans-Pacific cable capacity by around 20 per cent.[2]

That's $ 42 million for a terabyte of bandwidth.

https://twitter.com/elonmusk/status/1128834111878193155

Starlink mission will be heaviest @SpaceX payload ever at 18.5 tons. If all goes well, each launch of 60 satellites will generate more power than Space Station & deliver 1 terabit of bandwidth to Earth.

https://www.teslarati.com/spacex-secures-starlink-funding-launch-scrubbed/

As previously discussed on Teslarati, in the last four years, OneWeb has raised $3.4B of funding, while SpaceX – a company primarily focused on building and launching rockets – has raised $2B, half of which is known to be dedicated to Starlink. OneWeb’s constellation (either 650 or 2650 satellites) cost estimate has grown quite a bit recently and stands at ~$5B. Assuming all $2B of the funding SpaceX has raised is dedicated to Starlink, that would translate to a per-satellite cost – including all infrastructure and launch – of $450,000 for the first phase (~4400 satellites).

60 satellites (terabyte of satellite bandwidth) on 450 thousand dollars will cost 27 million dollars.

In General, satellite Internet will cost 1.5 times cheaper than wired. Additionally, the transfer on the radio channel will have a lower ping (the speed of propagation of electromagnetic waves in optics is much less than in vacuum).

[Sigmetnow]

Hi, ArticMelt2.  Good info.  There is a SpaceX thread hidden over in “The Rest” section.  See you there, later! 

https://forum.arctic-sea-ice.net/index.php/topic,2582.msg200439.html#msg200439

[ArcticMelt2]

The richest man in the world believes that we should build space colonies not on Mars, but in outer space (large space stations with artificial gravity).

https://www.cnbc.com/2019/03/08/jeff-bezos-mount-everest-is-a-garden-paradise-compared-to-mars.html

Jeff Bezos: Forget Mars, humans will live in these free-floating space pod colonies

Richest man alive Jeff Bezos says Mars is not a place humans would be comfortable living.

“My friends who want to move to Mars? I say, ‘Do me a favor, go live on the top of Mount Everest for a year first, and see if you like it — because it’s a garden paradise compared to Mars,’” Bezos said at the Yale Club in New York City in February, according to a Business Insider transcript.

That is not to say that Bezos, who founded Amazon and aerospace company Blue Origin, is not interested in sending regular people to space. Bezos says moving to space will become necessary as the population is expanding and Earth’s resources are finite. Eventually, an Earth-bound population would face population control and energy rationing, Bezos said.

”...[T]hat to me seems like a pretty bleak world. We don’t have to have that,” Bezos said.

There are currently over 7.6 billion people on earth, but if space becomes a viable place for humans to live, the solar system has enough resources to support 1 trillion humans, Bezos said. “Then we’d have 1,000 Mozarts and 1,000 Einsteins. Think how incredible and dynamic that civilization will be.”

However, said Bezos, “I don’t think we’ll live on planets.” Instead he envisions humans living in self-sufficient space structures, like those designed by Princeton physics professor Gerard O’Neil.

“The space colonies we’ll build will have many advantages. The primary one is that they’ll be close to Earth. The transit time and the amount of energy required to move between planets is so high,” Bezos said.

“Ultimately what will happen, is this planet will be zoned residential and light industry. We’ll have universities here and so on, but we won’t do heavy industry here. Why would we? This is the gem of the solar system. Why would we do heavy industry here? It’s nonsense.”

The artist rendering below is an artist rendering of inside of one of O’Neill’s space settlement cylinders, according to the National Space Society.

[ArcticMelt2]

Below is an artist rendering of the exterior of what one of O’Neil’s space settlements would look like.

https://en.wikipedia.org/wiki/O%27Neill_cylinder

[ArcticMelt2]

The simplest station with artificial gravity is featured in the movie Moon Racer.

[ArcticMelt2]

In the future, Bezos will be Mask's main competitor in the colonization of space.

Reusable Bezos's missiles now can only make suborbital flights.



But in the coming years it is planned to create a large reusable orbital rocket - the New Glen. This rocket is much larger than the Falcon:



And besides, Bezos is much richer than Mask.
 
https://www.forbes.com/profile/jeff-bezos/?list=billionaires#7ce87d531b23

#1 Jeff Bezos & family
CEO and Founder, Amazon

REAL TIME NET WORTH
$144.6B
as of 6/7/19
2019 BILLIONAIRES NET WORTH
$131B

https://www.forbes.com/profile/elon-musk/?list=billionaires#5d2ab9f17999

#40 Elon Musk
CEO and Chairman, Tesla

REAL TIME NET WORTH
$18.6B
as of 6/7/19
2019 BILLIONAIRES NET WORTH
$22.3B

[ArcticMelt2]

It is proposed to make one of the ends of the space cylinder transparent, with a direction to the Sun. In this way, natural lighting in a space colony can be simulated.



To create cylinders it is mainly proposed to use material from small celestial bodies (asteroid and comets with minimum first cosmic velocity), and also possibly from the Moon and Mars.

[ArcticMelt2]

In a recent film (2004), NASA is building a similar space cylinder to save all of humanity from an environmental disaster.

https://en.wikipedia.org/wiki/Interstellar_(film)

In the mid-21st century, crop blights and dust storms threaten humanity's survival. Corn is the last viable crop. The world has also evolved into a post-truth society where younger generations are taught ideas such as the Apollo moon missions were faked

Based on their data, Professor Brand conceived two plans to ensure humanity's survival. Plan A involves developing a gravitational propulsion theory to propel a mass exodus, while Plan B involves launching the Endurance spacecraft carrying 5,000 frozen human embryos to colonize a habitable planet.

Space colony shown in the film:

https://interstellarfilm.fandom.com/wiki/Cooper_Station

[kassy]

Of course these are tech dreams.

How could you live in space if you cannot even manage a planet.

[Shared Humanity]

The last refuge for a doomed people is always fantasy. This thread is as good as most.

[Sigmetnow]

NASA will allow private astronauts on the ISS for $11,250-$22,500 a day
The space agency wants to create a sustainable economy in low Earth orbit.

On Thursday morning, NASA held a press conference to announce that the International Space Station is now open for business. Previously, commercial organizations have only been able to use the ISS for research purposes; now NASA is open to letting them make a profit in low Earth orbit (LEO).

https://arstechnica.com/science/2019/06/nasa-will-allow-private-astronauts-on-the-iss-for-11250-22500-a-day/

Bigelow Aerospace (@BigelowSpace) 6/7/19, 11:06 AM
Bigelow Space Operations has made significant deposits for the ability to fly up to 16 people to the International Space Station on 4 dedicated @SpaceX flights. Photo credit: @NASA

https://twitter.com/bigelowspace/status/1137012892191076353
Image below.
< < They've already sent an inflatable habitat module to ISS for testing, and NASA has a copy of it at Johnson Space Center for further validation

https://en.m.wikipedia.org/wiki/Bigelow_Expandable_Activity_Module

[kassy]

Space tourism is not space colonization.

[Sigmetnow]

Space tourism is not space colonization.

How do you think space colonization starts?
With those first brave explorers.

[ArcticMelt2]

How could you live in space if you cannot even manage a planet.

Do you think that on large cruise ships there should be no lifeboats?

People need to build their own space colonies in order to insure against unexpected global catastrophes.

[ArcticMelt2]

I think the creation of these colonies will be much cheaper than the full-scale implementation of carbon capture and storage projects.

Moreover, there is simply no place on Earth where you can safely store huge amounts of carbon:



Need to send this carbon to space? Sending trillions of tons of carbon to space will require trillions of dollars. Such costs will be comparable to the creation of the largest space colonies.