Closest Temperate World Orbiting Quiet Star Discovered
eso.org
eso.org
https://www.quantamagazine.org/neutron-star-collision-shakes...
https://www.quantamagazine.org/squishy-or-solid-a-neutron-st...
For instance, did you know that Saturn's rings are made of rocks that are separated by very human-scale distances? I find these images valuable in communicating that fact:
https://www.quora.com/What-would-it-feel-like-to-touch-Satur...
https://www.eso.org/public/archives/releases/sciencepapers/e...
I think these sort of artists conceptions really help the public visualize, understand, and get inspired by the research. I imagine it would be a lot harder to get funding for the research without them.
https://en.wikipedia.org/wiki/Red_dwarf
"Red dwarfs therefore develop very slowly, maintaining a constant luminosity and spectral type for trillions of years, until their fuel is depleted. Because of the comparatively short age of the universe, no red dwarfs exist at advanced stages of evolution."
And here I thought because of their small size they'd be LESS suitable for life.
The key is to remember that you have more than one variable to play with; it's not just overall stellar output, but orbital radius as well.
https://en.wikipedia.org/wiki/Habitability_of_red_dwarf_syst...
It's interesting to think about the old maps with "here be dragons" around the edge... on tide-locked worlds such maps could effectively be true.
"I mean, it would be so unstable! Even with a thick atmosphere, temperatures at one point would fluctuate by tens of degrees, hundreds of times a year! Plants would be unable to photosynthesise for half the time! Animals would be blinded!"
Habitable planets would orbit so close that they would likely be tidally locked, and one side would always face the star, while the other would always be dark. The temperature variation could pose major problems for habitability.
Red Dwarf stars are prone to intense flares, which could easily drive off an atmosphere.
Red Dwarf stars are likely not where we should look.
Not that either of those are in the top 1,000 problems of colonizing another system.
The future was supposed to have surface lighting.
Colonies on the moon might sound cool, but there's no real economic benefit, and the cost is astronomical.
Humans are attuned to survival not coordinating millions of people to a common goal.
Give us a break!
Von Braun was the first to make a guided rocket (developments like the de Laval nozzle and rocket equation had just been discovered). The US poached him and sent him to West Texas, then Alabama, without a whole lot to do. Probably to keep him out of enemy hands. The US government had their money and "intelligence communities" lined up behind the Vanguard rocket. It was only because the Vanguard rocket failed so embarassingly while the Soviets won the space race that Eisenhower started NASA and gave Von Braun some funding. So Von Braun wrote a letter to Kennedy, and he got his childhood wish to go to the moon. And he did it. The greatest engineering and technological achievement in history. All the politics (like cost-plus suppliers) still hurt the program, but they really made a lot of progress. So then the new NASA bureaucracy pushed him out and went on to do bureaucratic things like build the ridiculously badly conceived STS (they proposed ideas and Nixon picked it), and crash it even when NASA engineers told them before hand that a foam strike was going to happen as was the case with the Challenger Groupthink disaster.
The Soviets also had plenty of childish and embarassing dramas and politics of their own going on as well.
It's all a shame, really. People can do amazing things, but I'm not willing to pretend our shortcomings aren't because of moral failings.
There is no legitimately good reason for the Challenger disaster, or having to rely on Russians for their superior rocket tech to get into orbit.
The upside of this is that if we can maintain this cocktail of traits while curbing the more obviously dangerous ones, we may be able to surpass greatly what we've accomplished so far. I hope anyway.
Ultimately what seems to drive us forward (IMHO), is finding new ways to kill each other.
Tom Lehrer's take strikes me about right: https://m.youtube.com/watch?v=5V7me25aNtI
However, during the end of WWII he intentionally surrendered himself, his team and capital into our hands -- the Americans. He came to America, assimilated and oversaw the greatest engineering feat in history when we were losing the space race to Russia, and would have continued to lose without him.
I would also consider, what should he or could he have done in his time? OK, how about what have I or you done to stop the genocide in Darfur? Nobody in the Western world did much, and we didn't do anything at all about the Cambodian genocide. The American Government has also never officially acknowledged the Native American genocide, or paid reparations for it--these would be crimes in Germany today.
In my mind it is important to address these moral questions, which are indeed difficult, but if we are not honest about them then we find can at times be the pot calling the kettle black.
(Has this ever been explored in fiction, a very determined and patient civilization digging themselves out of an unrocketably deep gravity well?)
Yes, spacecraft are more fragile than pellets, and canned primates even more so, but a ludicrously long acceleration track is still going to cost peanuts compared to the kind of planetary liposuction you're talking about.
Maybe you could launch materials and construction robots for an elevator using a mass driver then use the elevator for passengers, I dunno. Still need some non-rocket way to get things up there.
So are we getting fatter or slimmer? By a quick Google survey it depends which estimates one trusts, but probably losing a bit.
Everything is economically viable when you can employ fantasy magic technology to make it happen.
Are you familiar with the companies that are being set up to do this, and that are backed by Eric Schmidt et al?
Even if the odds of life are astronomically low (one in a billion), there are billions of galaxies, with billions of stars.
The odds are good, but the results are irrelevant. Only 5% of the stars that we see can emit light presently that will ever reach us - they will all recede beyond our cosmological horizon.
There is very likely life elsewhere, and it makes no difference.
We can't know how probable life is given similar conditions to Earth because our sample size is too small. But there are definitely a lot of Earth-like planets out there.
How do we know that there isn't life teeming in our galaxy if we can't even detect neutrino/quantum/ansible/tech-undiscovered signals?
We do not know and cannot show any viable means of creating the full sequence of pre-biotic chemicals needed for the first organism to exist. When one of the top organic chemists in the world puts out that challenge and nobody responds, one can then say that all of these experts know full well that they do not have a clue and are just deluding everyone else as to how life even came to be.
Just using probability to say that life came about without at least a semblance of an idea of possible sequences that could work is useless. You need at least some possible viable sequence for the full biotic complement of chemicals to be available. Since the sequence requires processes and solvents that are inimical to previous and follow-on chemicals, this sequence development is a major, major problem that is regularly ignored by those who use probability to say life can arise.
When these things are taken into account, the simple fact that there is life here on this planet can be seen as a unique event throughout all of the universe.
On some estimates of random action giving rise to life anywhere in the universe, the probabilities are so low that the universe would need to exist for many magnitudes of time longer than its apparent age at this time. Your "one in a billion" is oh so many magnitudes of order higher than the probabilities estimated.
Of course, your view can be very different and if you can come up with a viable sequence then simply accept the challenge that has been put out. There will be an awful lot of relief if this could be done.
One thing we do know to be extremely unlikely: That we - exactly we, us, here at this specific point in time - should somehow have arrived at a point where we can confidently secondguess the universe in all its glorious details. We can't, and we don't really even have the foggiest idea what kind of life is possible, or how it comes about in the first place.
All the Drake equations in the world can't hide the fact that we know nothing. Every single galaxy may be bursting with life, or we may the only specimens anywhere in the dark, cold void.
My personal guess - which is no better or no worse than anyone else's - is that life or its functional equivalents is more or less everywhere, but that intelligent critters like ourselves are exceedingly rare.
There are many more stars than chemsists, and the universe has had much more time to get lucky than our chemists have had. The universe has gone through more chemical permutations than our scientists can dream of.
Maybe you could explain it as "if rockets had advanced as fast as computers, we'd have flying cities that could travel to the moon and back in minutes."
And would people living on the moon have really changed her life either? Unless she was one of them she'd just end up hearing about it in the news and then going about her day.
TBH if I really had to pick the thing that has most changed her life I'd bet it's the shipping and logistics technology that has dramatically lowered the cost of all the consumer goods she buys.
As to people living on the moon: she grew up with America being this frontier that was very inspiring. I think she sees space travel the same way (also, probably bias from reading a lot of sci-fi of the time).
If progress in space travel seems slow, remember that almost all of the money going into it is spent by a single organisation whose budget is less than 10% of Apple's revenue.
However they're still wearing fur-lined space suits and calculating trajectories using slide rulers.
Predicting future technology (especially new out of the box ideas) is really hard.
Sure, if a "clone" of Earth is found, it would make things created here more reusable on the new planet, but seems like a pretty limited way of viewing the potential for ventures in space.
More to the point, is anyone aware of the requirements of non-planet staged space operations would look like and how viable such plans would be compared to planet dependent operations.
1. If we're already going to do the journey to a far off planet, it'd be nice if we didn't have to have a huge amount of infrastructure to stay alive on the planet.
2. I feel like one of the ultimate goals of space travel is to find other life. The only life we know is on Earth. Earth-like planets are a good place to start.
Dangerous assumption. That's like saying the purpose of science is to unify nature. If nature isn't unified, the goal won't make it so.
The most likely outcome is probably that we will become our own aliens. Once we send out colony ships, those people will form their own branches of the evolutionary tree. Over millennia, that will equal aliens. It doesn't really matter that they're our ancestors when they end up looking, talking, and acting completely alien.
This seems far more likely than running across other life in the local group. We're forever imprisoned to our local group, which is something like 0.001% of the observable universe. And for all we know, the total universe could be infinite. This requires strange assumptions, like running into your own doppelgangers, and infinite energy. But we can't know it's not true. And in such a circumstance, we have to face the unsettling half-empty truth that we're simply alone.
A lot of sci fi seems to somehow overlook our cultural/social baggage and yet those are precisely what are crippling us now, and likely to retard our progress in the future too, if not outright destroy us.
To clarify, I believe that within a generation or two, people on another planet will hardly relate to their originating culture and will see it as an other. This change will at first be benign, merely based on differences of day-to-day life on a developing colony, but later, after initial material support largely dissipates, would see it as something to cast off or, should they not openly revolt or request a plebiscite, will treat it diplomatically as if it were another country, or as it is in this case, as literally another world.
Consider that when traveling between a host and colony settlement takes literal weeks, months, or years, sending information would likely also similarly be costly and would take prohibitively long times for many real time applications: latency up to several hours or days to arrive could be expected for even small downloads. This borderline resets communication the era of writing letters, if I may be a bit dramatic, because this absolutely neuters a huge amount of modern culture.
Cultural products made on earth would be costly and difficult to ship, so we’d find that earth films, games, internet, are mostly not going to bridge the gap. Even after infrastructure for communication improves, the latency problem of “space is big” isn’t going to go away. For example, would you read 15 HN pages if each page, no images, no modifications, took 15 minutes to load? I suspect not, and you’d fill that time with something else that an earthling software engineer might not.
It’s all elements of culture. The earth news cycle? Almost wholly irrelevant, besides economics and space-related news, which impacts what is sent and relations with home.
Celebrities? People will find it hard to care about celebrities who will never visit them, and who have works they’re not hearing until weeks, months, or years after they stopped being relevant on Earth.
To fill this gap, people on the colonies will be making their own, and however bad the gap is earth -> space culture wise, due to the difficulty that limited resources will impose, culture from space -> earth will likely be rather rare.
So, culture is going to start diverging, relatively hard and rapidly. Separated from leaders, most current cultural information, old national borders, credible risk of counterattack from earth for anything short of armed revolution (space war or military pacification against one’s own people would likely be an economic and political Vietnam, and you definitely can’t launch a surprise attack when people can see the weapons or troops launching), people will mostly stop giving a shit about their home world and will become naturalized on their new ones.
Two or three more generations like that and you’ll eventually be talking about people on Mars, for example, as if they were from Australia.
One convenient circumstance: A breathable Earthlike atmosphere will float at that altitude, so it would be easy to live in floating balloon habitats.
Also, exchanging the fixed geography of land for the fluid geography of fluid might result in changes to the underlying nature of society. In hunter gatherer days, dissenters could simply walk to a different part of the environment. Farmer's fields and defensive walls anchored people to particular pieces of land. If everyone lived in mobile floating habitats, everyone would be free to move. This is quite likely to change the nature of government.
You also get this in a Dyson Swarm, but there's a matter of scale. A minimum viable space colony is likely to be larger and more expensive than a minimum viable floating Venusian compound.
With floating cities, the idea of a space elevator isn't that crazy. What could we do with space elevators on Venus?
What if the small balloons were the size of a Las Vegas resort, and the average ones where something like Manhattan?
I wonder if there'd be some tangible benefit to colonizing Venus for adventurous entrepreneurial types... "There's gold in and/or on them thar clouds!"
The society that might arise in an entirely fluid, borderless geography might have a certain attraction. Venus might wind up being the next Las Vegas, writ large in the 21st century.
With floating cities, the idea of a space elevator isn't that crazy. What could we do with space elevators on Venus?
You could have ultra-high altitude balloons that can act as staging centers for rotorvators. Those would be way cheaper than space elevators to manufacture.
The lower atmosphere of Venus is denser than the surface of Earth’s ocean, but with extremely violent currents. The upper atmosphere - at the “inhabitable” level - has similar but much less dense winds, with the added henefit of a charmingly toxic and aggressive haze of sulphuric acid.
It might just about be possible to build a floating research station, at vast effort and expense, but floating cities are not going to happen without some near-magical breakthroughs in materials science and engineering.
And without access to the surface, there isn’t much to do above Venus anyway.
The acid clouds aren't that bad. People have even worked out how to manufacture PTFE out of the Venusian atmosphere, so there's your acid proofing right there. We already know how to build lighter than air craft.
And without access to the surface, there isn’t much to do above Venus anyway.
Access to the surface is perfectly doable using teleoperated robots. You can lower them onto the surface with a store of a phase-change substance for cooling. Dry ice might be suitable for that. When they run out, you haul them back up.
There's wasn't that much to do in the desert where Las Vegas is located, either.
MgH2 -> Mg + H2 (thermolysis @ 287 degC)
CO2 + H2 --Fe-> CO + H2O (water-gas shift)
CO + H2 --Fe-> C + H2O (Bosch)
CO2 + 4 H2 --Ni-> CH4 + 2 H2O (Sabatier)
2n+1 H2 + n CO --metal--> CnH(2n+2) + n H2O (Fischer-Tropsch)
2 Mg + CO2 -> 2 MgO + C
CaH2 + 2 H2O -> Ca(OH)2 + 2 H2
Ca(OH)2 + CO2 -> CaCO3 + H2OThe primary concern would be that Earth-gas would not be a good enough lifting gas in the CO2-depleted Venus atmosphere to keep the floating habitat at a cool enough altitude. Hydrogen-filled chambers would certainly work for that, but you would have to bring that hydrogen with you to Venus. By the time atmospheric oxygen becomes a risk, you would just land the dirigible and burn the hydrogen in a controlled fashion.
Why not extract the hydrogen out of the clouds of acid?
You could bring along MgH2, then once you hit the atmosphere, you can thermally decompose it into Mg and H2, then react the Mg with sulfuric acid to get MgSO4 and another H2.
O'Neill was overoptimistic about launch prices coming down in the near term and about the economic case for solar power satellites and for people in space to mine the materials and build and maintain the powersats, etc. But as I remember it this community made a good case that you don't need planets to live on; with their gravity wells and atmospheres and night/day cycles they're mostly a big nuisance compared to free-space habitats built with lunar and asteroid materials.
From these discoveries, it seems that truly earth-like planets around sun-like stars are rare, but i think it might be more of a drunk under a lamp-post looking for his keys because that’s where the light is.
Maybe, but we haven't looked everywhere the light is yet, so why struggle to look in the dark?
(Sorry, my disability sometimes makes it a little difficult to understand what people are saying. Genuinely not being a dick about this.)
Then they can start debating whether the CO2 level going from 0.03% to 0.04% indicates we're entering another extinction period. If they're within a few light-decades then the next century will be a very exciting time for their astro-xeno-biologists. Lucky them!
What's the current status of the EMDrive? Has it stalled? Is there a space-faring test due soon to see if it actually works in space?
It's seemed to have dropped off the news completely. (Reddit emdrive shows nothing of note.)
I recommend this video for a good explanation [0].
Gonna go way out on a limb here and guess "because it's totally fake" is the most likely reason.
Or even better a combination of EM and Alcubierre drive one for "city" cruising one for the "highway".
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...
The fastest feasible technology for human-carrying ships is the fission fragment rocket, with a burnout velocity of about 0.1c. That's 40 years to Proxima b. An 11 ly trip to this world would not be feasible, because a multi-generational ship with the payload fraction needed to hit 0.1c is not feasible.
Probes can be much lighter, enabling higher payload fractions and faster trips.
Right now, between 10,000 and 100,000 years.
Under 100 years is probably outside of possible without some fundamental breakthrough which we can't forsee. (and at this point it matters from whose perspective the time is measured)
Between 100 and 10,000 is the realm of at least plausible science fiction.
We don't _have_ any technology for interstellar travel because nobody has developed it.
Of course, that's not a small assumption...
That may seem like "equivalent to forbidden", but some of the interesting surprises of quantum physics were originally theorized by Einstein and company as a way to disprove quantum physics because they were clearly too weird to be true. Maybe not as weird as "Oh, you thought an event's cause had to precede its effect? LOL.", but bizarre and non-intuitive nonetheless.
The spacecraft doesn't actually move through space it pulls the space where it needs to go towards the spacecraft and pushes away the space behind it.
I'm no rocket surgeon so don't quote me.
After all, clearly Star Trek the series has time traveled from the future and is aware of the Vulkans thereby satisfying the prime directive.
In any case, it would be interesting if someone is seriously working on anything like this. I don't track current research in any related areas.
Admittedly it's a big ask. But not as big as bending space.
https://en.wikipedia.org/wiki/Space_travel_using_constant_ac...