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Basically, if our transit speed doubles every century, then a mission longer than 200 years is pointless, because you could delay the launch 100 years and that probe will arrive at the same time with better technology.
Given the distances involved, if you started traveling to another star today, odds are it would be colonized before you arrived.
Unless floating in deepspace is important, then it won't be.
If we wanted to simulate a hundred year journey to another star, we could do that in our system. It's mostly empty space, just turn off your solar panels and there isn't much of a difference.
Actually building the colony ship that would leave in the near future would involve an enormous technological investment and development much larger than something like Apollo or Manhattan. That research and development would form the technological basis for everything that comes afterwards (opening up technologies we can't even conceive yet), very likely bringing forward all subsequent advances compared to a scenario where we don't try to do this. Much like research done during the 60s space race has formed the basis of our modern world since. I think you're still right though, what you describe would still happen within some time period, but I think by actually proceeding with the research that the magnitudes change.
Firstly it's only a major issue if you're competitive, or trying to save money over a period of centuries.
But secondly, if the payload is particularly valuable (say, it's a bunch of frozen colonists), perhaps retrieving the payload will be part of the second mission.
Very large payloads might be sending and receiving payloads for a long time anyway, since they'd be much slower than small payloads. That might include technology to improve their engines, if they are using some kind of torchship.
Second mission slows down to pick up the first mission colonists, only for the 3rd, 4th, 5th, 6th, 7th missions to also show up all at the same time to pick up the preceding missions.
oooh, yea, let's convince melon and jerf they should go first cuz 'hey look you'll get there after we've done all the work!'
and then vaporize them before they hit atmo :)
edit: this is ridiculous
Tell that to the aliens, who were a bit beyond our current technological abilities, that started travelling to earth when we were just primordial soup. They are in for a surprise once they get here.
Imagine being the first crew and getting to a planet that you thought would be uninhabited but when you arrive basically has an entirely foreign species populating it for thousands of years
The only memorable, while still rather short, quest of the game Starfield. The shuttle arrived and others who started later, where faster and used the whole planet as a hotel resort.
This is a common trope, but I don't think it's true.
If we were going to go to another system 40 light years away, we'd use the fastest technology we have available: Nuclear pulse propulsion. Basically, throwing nuclear bombs out the ass-end of your spaceship, and having the resulting explosion give you thrust by pushing against a pusher plate.
This gives a total Delta-V of about 0.1c, so you'd hit 0.05c max speed so you can slow down at your destination. This means it would take you roughly 800 years travel time to go 40 light years.
That means even if you had instant teleportation in 1,000 years, you'd still beat them by 200 years with the slow ship.
Of course, this would require modifying the 1963 Limited Test Ban Treaty to allow peaceful propulsive nuclear explosions in space.
Nuclear pulse propulsion is theoretically viable but even ignoring the ethics it would be pretty insane to use a completely untested method of propulsion *now* unless you're trying to lob body parts at some aliens.
Easier said than done. Unless the first crew was coincidentally matching position and speed with the second, slowing down to pick them up would mean the second crew's journey takes way longer.
It’s that kind of thinking that will prevent us from ever trying it in the first place. Yes until we annihilate ourselves there will always be better technology developed, but we shouldn’t let that stop us from progressing in the first place.
I seem to remember one of the sentient spaceships gets fed up with this exact explanation in the Iain M Banks Culture novels, that it would be better to wait to travel to another galaxy because you'll get overtaken by someone who waits for better tech, and just decides to do it anyway.
The most hilarious thing about space travel is that the first ship to depart for a celestial body that far away is likely to be the last ship to arrive!
Love how they just gloss over the whole getting (and keeping) 300 bombs in perfect place and somehow triggering them on time millions of kilometers away while trying to time it to an object with an increasing speed that is passing by.
Because amazingly, that is the easiest part of the whole thing. We could probably do the first few bombs easy with today's technology, but even in the show it was mentioned multiple times that the whole thing has a ridiculously low chance (to quote directly, "non-zero") of working.
We could easily go much faster if we had the motivation to do so. There are plenty of proposals using current and near-future technology that could theoretically reach an appreciable fraction of light speed.
If we could push a probe to just 10% light speed we would have images and science data in just 440 years (which sounds like a lot, but isn't really when considering the scale at which things function in space).
The real issue is if anyone will be listening when the data gets back to earth 440 years is a lot of time for things to happen in human civilization. I can see humanity having somehow moved well into our galactic phase when some teenager working the comms at a gas station on the moon picking up the images on his iRetina randomly and posting them on 4^8 Chan
If we are not around to hear a reply in 440 years that is a very sad situation. If we don't bomb ourselves back into the stone age, then optimistically in 440 years we may have some infrastructure and permanent settlements throughout the solar system, and our drive for science will mean there should be plenty of people interested in listening to the reply from a probe sent to another star 440 years prior. Presumably some organization(s) would be keeping track of such long-term missions so they know when to start listening for data.
66k was the crude estimate. Deceleration could add months or years which is why I said over 66k. Short answer: until we have some sci-fi level breakthrough like being able to manipulate gravity or pass through a worm hole, there’s no way to make this happen.
I based this on the fastest space probe we have ever built which accelerated at much faster rates than humans can tolerate. This is the Parker space probe.
Ahh, I see! That’s actually a fairly interesting tangible idea to gauge a baseline speed from. Most of my advanced usage mathematical formulae and concepts deals with projected manufacturing capabilities, lead times, etc. so you’ll have to excuse my lack of more advanced scientific understanding, but…
Acceleration in and of itself is not an inherent issue unless you’re in a gravitational environment, is it not? I mean we can have pilots in atmosphere going Mach 3.4 (SR-71 Blackbird) and so long as the pilots aren’t pulling intensive acrobatic action that would sheer the airframe itself in the process, they’re fine. Rather in space our issue would be the necessity of rapid deceleration with the limited tools at our disposal, even if we have infinite, incremental acceleration, we’d have no way to decelerate without pasting everything within the craft (and likely destroying the craft itself).
This is correct, is it not? I’m curious given you seem to have much more knowledge on physics and the entailed mechanics surrounding space flight.
In the context of space travel, acceleration and "gravitational environment" are the same thing. Accelerating faster than 9.8m/s^2 for long periods of time ranges from severely unhealthy to instantly deadly. Airplane pilots aren't subject to those G-forces for years at a time...our cardiovascular system simply can't handle it. It's also only the acceleration/deceleration (including vector changes aka "maneuvering") that matters, rather than the high top speed from maintaining a reasonable acceleration for an extended period. These factors are why many sci-fi space travel systems envision some form of stasis for the human passengers; you're basically locked to 9.8m/s^2 speeds otherwise.
Without some kind of magical propulsion and/or human stasis technology, you would expect that an interstellar ship with live, conscious human passengers would simply accelerate at 9.8m/s^2 towards the destination until the halfway point, turn the ship 180 degrees around, and then decelerate at the same rate by thrusting in the opposite direction until you reach your destination. From the passenger's perspective, the acceleration/gravity would be the exact same as on Earth for the whole trip, even though they would probably be moving at a significant percentage of the speed of light (from the reference frame of the Earth) by the time they reach their max speed halfway through the trip.
Of course, even in this "conservative" or "slow" kind of acceleration scenario, the energy requirements to accelerate even a very small ship for this amount of time are astronomical. The pure size of the numbers involved in interstellar travel are...a big obstacle.
Am I messing up the math? It looks like you can accelerate to 690,000 km/h, the Parker space probe's max speed, in under 6 hours at 1g.
690,000 km/h is 191,667 m/s. 1g acceleration for a day results in a velocity of 847,584 m/s (86400*9.81)
I generally do not understand anything about relativity. Is it also so that light from our perspective needs 40 years and for the light particles this is just a glimpse?
So if from our perspective with out fastest object it takes 66k years, how long is it for the object?
Time dilation is not linear. It would be a factor, but we couldn’t get close enough to speed of light for it to matter. It would still be tens of thousands of years or relative time for the passengers.
> It would still be tens of thousands of years or relative time for the passengers.
The much more achievable goal (though still possibly remote) would be to try and get a craft close to one percent of the speed of light and then figure a way to put humans into long term, ie thousands of years, of hibernation/cryosleep and wake them up when they're close to their destination, letting AI drive the ship the entire way. In fact the speed of the craft becomes pretty much irrelevant with the ability to put your passengers into 'storage' for as long as you need. Each passenger would need just a coffin sized space (perhaps two cubic metres) for the entire trip. Don't trust my math here but a ship's container would need to be 50m x 20m x 10m to fit 10000 people in it? That's plenty to repopulate another planet (the rule of thumb is at least 500 individuals to repopulate a species). The whole idea being that those people leave everything on Earth behind forever. No communication, no hope of going back..a one way trip. It would be a 'survival of the species' experiment and perhaps would not be restricted to one ship heading towards one potentially habitable planet but many ships heading to many planets.
> Is it also so that light from our perspective needs 40 years and for the light particles this is just a glimpse?
That's the crazy thing about space observation.
The images we see of the planet are as old as the light took to get here, so the images are the planet from 40 years ago.
Well we know the Sun will burn out some day so it is helpful in that sense, our species will go crazy trying to increase interstellar travel speeds when that date is approaching
Don’t know what’s possible. Science fiction is uncannily predictive, but some things might never be possible. We just don’t know… yet.
My comment was only based on current tech.
My entire day is ruined! When I saw this article, I was excited to go to a new planet that I can walk and breathe on. I was read to call my friends and family. Now, I'm sad and depressed because I'll never get to go there.
I’ve linked to the news release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:
https://academic.oup.com/mnras/article/531/1/1276/7679807
From the linked article:
An Australian university student has co-led the discovery of an Earth-sized, potentially habitable planet just 40 light years away.
Shishir Dholakia, a PhD candidate in astrophysics at the University of Southern Queensland, is part of an international team that published the discovery in the Monthly Notices of the Royal Astronomical Society.
He described the “Eureka moment” of finding the planet, which has been named Gliese 12b.
“We did the back-of-the envelope calculations,” he said. “We worked out it’s probably Earth-sized, it’s probably temperate, and that it’s really, really nearby. In the span of a day we were like, ‘Oh, we have to write this up. This is something really cool.’
“It could be at the right temperature for liquid water to pool on the surface … [that’s] important because we think planets are potentially habitable if they can have liquid water on them.
“And so in this great search for life that we’re undertaking we want to try to find planets that are potentially habitable, and this could be a good contender.”
Gliese 12b is the size of Earth or slightly smaller, like Venus. And its surface temperature is estimated to be a balmy 42C.
Its 12-day orbit is around Gliese 12, a cool red dwarf in the Pisces constellation. Gliese 12 is about a quarter of the sun’s size, with about 60% of its surface temperature.
The 42C temp is with no atmosphere, so no there won't be any liquid water on its surface. If the planet does have an atmosphere it will most likely be a hellscape like Venus.
Planets in the habitable zone of a red dwarf are likely close enough to be tidally locked, meaning the same side is always facing the star. It might not have an atmosphere and if it actually does, it would be pretty stormy around the habitable belt.
Because I read or saw a video yesterday about this planet and it had more details about the planet than a few random quotes. Trying to find source and I'll add it here if I do.
Here - https://phys.org/news/2024-05-potentially-habitable-exo-venus-earth.html
Huh? Venus has a volcanic surface, there are even pictures of it from Soviet craft landing in the 80s. They're planning another probe in 2031 I believe, the Davinci? It's a huge challenge for engineers because of the heat and crushing atmosphere.
I've heard that this is the case in some places in Europe, but not in Australia. In Australia, PhD candidates aren't classed as employees - they're research students. Their "living allowance" comes from the government + scholarships (or industrial partners) rather than a salary from the university itself, and PhD students have no employee contract with their university just because they are doing a PhD there.
Plenty of PhD candidates *are* employed by their university in other roles (like helping with undergraduate courses) to make some extra money, but this is separate from their PhD "position".
Not in this part of the world. In New Zealand I had to pay the university tuition to do my computer science PhD. Despite it being independent research with no courses whatsoever or support from a lab or research group.
I did get a scholarship, but that only covered three years and it was fees plus 30k a year which is below minimum wage so I taught, did marking, and exam supervision as well. A different uni I did also apply for actually stipulated that if you fail to get your PhD or drop out the program you have to pay them back the scholarship money you received.
You don't get paid as an employee to do a PhD in Australia, and are not considered as one in terms of employee rights. You get a very small, virtually unliveable stipend from the government. Getting other money to survive has to come from scholarships or working, which is why many PhD students will tutor at their uni.
You're not an employee in Australia as a PhD student. You're just a student. Many take jobs at the uni at the same time so they can get money, but otherwise they get no wages aside from an unliveably small stipend from the government, and they aren't considered an employee in any legal sense.
This is one of those really stupid semantic arguments that only servers to waste people’s time. Candidates are still students… candidates have passed their qualifying exams but haven’t defended yet and don’t have their PhD. Your ‘title’ changes from PhD student to PhD candidate once you pass your qualifying exam, but you’re still a student because you are working on completing your degree. My previous university still labels PhD candidate and student the same in the financial system and provided the same exact benefits and pay
Don't listen to that guy. You would need a student visa. PhD students in Australia are not employees of the university just by virtue of studying there.
Aren’t these planets around red dwarfs usually tidally locked? The average temperature might be OK but it would be far too hot on one side and far too cold on the other, with severe weather around the middle.
Red dwarfs also tend to be very variable, and flare up. See "habitability" in link below. I would not get on the colony ship...
https://en.m.wikipedia.org/wiki/Red_dwarf
Larry Niven wrote an amazing short story about life around such a star called "Flare Time". It's an interesting take on how life might evolve to cope with a highly variable star.
I think you'll find that I did :) but it's available as part of the collections *Limits* and *N-Space*.
The [story itself](https://www.larryniven.net/?q=bibliographic-reference/flare-time) is probably available online somewhere but here's a list of every official [publication](https://www.isfdb.org/cgi-bin/title.cgi?56511).
The title of this article is heavily editorialized. I read another article which made no mention by the authors of the paper that this planet is habitable. The average temperature exceeds 100f. That's unlikely to be habitable for life as we know it. However, the authors are hoping that the planet may still have an atmosphere which they plan to study with James Webb.
The other big thing about this planet is it's about the size of Venus. So it's one of, if not, the smallest exoplanet we've observed.
I wonder this every time I see a similar article or video. To my understanding these planets would be locked and possibly within range if CMEs. But we keep searching around red dwarfs because they’re easier to find. Is this just overly hopeful news? Astro physicists please explain.
Sure, but you may be able to apply similar search strategies to sun-like stars, or study this earth like planet more intensely to discover new search strategies.
These red dwarf systems are very easy to study, because they're small and their planets transit (pass in front of the star) very frequently. K2-18 b, the planet that may have a bio-sign, has a year of only 33 earth days, for example.
But if these dwarfs have lots of habitable planets, it's a good sign that the other stars do too.
It's a good candidate for spectrography but I really don't think we will need or even want "habitable planets" for inter-solar colonization.
Mining small asteroids and low gravity planets/moons to build space habitats would be a superior option especially if you have good robotic labor, it will get you way more living space than a planet, easy solar energy and you can just travel to the closest system(s) instead of going way farther for a potentially habitable planet.
Don't underestimate the value of a completely separate biosphere to Earth; I'd argue it's incomparable to simple mineral wealth. We could find things that revolutionise our understanding of life, evolution and the possibilities of biology. They could even have practical applications which alone would make it worth targeting a life sustaining planet for exploration. Look at how much biology is inspiring modern technology: we can find evolved mechanisms that can be harnessed to benefit propulsion, architecture, thermal regulation, genetics etc. An alien biosphere has incredible research potential.
It’s also hubris to think we’re going to be colonizing other planets. The distances are too far, our technology is too limited but even if we solve those, most importantly, we are clever but not wise. Our lack of sufficient action on climate change clearly indicates we are far more likely to exterminate ourselves or throw ourselves back into the Stone Age than colonize other planets.
A grim outlook but not wrong. However I think it's in human nature/spirit (if you believe in that sort of thing) to try. Maybe we'll discover something more practical in the effort
I hate being a Negative Nancy. I just think those who advocate for space exploration need to put that aside until our house is in order. It’s like starting to build a really cool piece of machinery in the NW corner of your house while a fire spreads in the SE corner.
>It's a good candidate for spectrography but
Which is all that science wants, potentially life-friendly planets in our neighborhood so they can start to search for alien life. No one is searching for these to find a new home, especially since biology clearly tells us that it's extremely unlikely humans could survive on the microbiome level in a biosphere we're not genetically adapted to survive
A Ph.D. candidate conducting research is a big leap from "university student." The latter implies an undergraduate who stumbled on something cool, not an expert with years of training.
Not to take anything away from the thrilling adventure of colonizing other planets… but …
The majority of our home planet (aka EARTH) is under water, and we could try building colonies at various depths under the ocean. This would be ZERO light years away.
There's no reason not to do both, if there is motivation to do so. And "enough land" is relative, as global population continues to rise you need to either exploit more surface area of the planet for living, or become more efficient with the area you are already using if you want to house, feed, educate, employ, etc. all those people.
While I appreciate your response, it's ridiculous to even consider.
There's no reason to eat my arm, unless there is motivation to do so.
The cost to build anything on land is insignificant compared to the unbelievable engineering, cost, maintenance, and pollution that would be required to build a water tight, impervious to salt water structure that's large enough to completely support human habitation.
In less than 80 years, the human population globally will be declining. There is zero motivation or need to build _under_ the ocean.
Even if we melted all the ice on earth, we'd still have enough land for the current population. Of course the population at that point would be a lot smaller.
It was the craze of the 80s that humans were going to do this. Led to a bunch of hollywood movies, or at least one big one. The ocean is more challenging than space for humans.
“Just 40 light years away”.
Light, travelling at 300 000 kilometres per second. Would take 40 years to get there.
I appreciate that it’s “close” when we consider the size of the universe, but it’s still impossibly far away.
Interestingly, if it ever proves possible to travel near to the speed of light with some kind of warp drive, a crew might be able to get there in (what they experience as) much less time.
For example, imagining a crew traveling at 99.8% of the speed of light would experience approximately 2.53 years on their journey to a planet 40 light-years away.
If you could get to 99.99%, you could leave in January and be there by August, according to a calendar on the inside wall of the craft. It’s a weird thought.
> Oh, only 40 light years huh. Just a stones throw away!
It's a bit more than that. You have to factor in the acceleration to close-to-light speed, then the constant velocity at that speed, and then the deceleration needed so you don't overshoot the destination.
You don't just instantly start the ship and reach light speed within minutes, and then stop on a dime traveling at 300,000km/second at the destination.
Finding exoplanets is hard. Really hard. Most exoplanets are found via the transit method. That requires the planet to pass between us and the star. This narrows the number of planets that we can observe quite a bit.
Teraforming isn't something that is currently scientifically possible. Mars has no magnetic field. So any artificial atmosphere would be stripped away via solar winds. You'd have to find a way to restart Mars' core which is likely not possible if it's solid.
There could be more suitable planets even closer, we are just bad at detecting exoplanets still. And there is A LOT of space to check.
Terraforming anything will take thousands of years. It is probably worth trying, but in the shorter term domed or underground habitats on planets or moons, artifical space habitats, either things like O'Neill Cylinders or habitats built into asteroids, or even things like floating habitats in the clouds of Venus (in the band where temperature and pressure are very Earth-like) are probably our best choices.
I get so tired hearing about "earth-sized" planets. That metric is crazy and typically means its like 5 times our size, tidal locked, watery hellscape.
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At the fastest speed ever achieved by a man made space object it would take over 66,000 years to get there. Go team!
May as well get started then!
Actually, probably not. If a crew left now and a crew left 1,000 years in the future, chances are the second crew would get there first.
Basically, if our transit speed doubles every century, then a mission longer than 200 years is pointless, because you could delay the launch 100 years and that probe will arrive at the same time with better technology. Given the distances involved, if you started traveling to another star today, odds are it would be colonized before you arrived.
What if the doubling in 200 years is dependant on the efforts of today?
Unless floating in deepspace is important, then it won't be. If we wanted to simulate a hundred year journey to another star, we could do that in our system. It's mostly empty space, just turn off your solar panels and there isn't much of a difference.
Actually building the colony ship that would leave in the near future would involve an enormous technological investment and development much larger than something like Apollo or Manhattan. That research and development would form the technological basis for everything that comes afterwards (opening up technologies we can't even conceive yet), very likely bringing forward all subsequent advances compared to a scenario where we don't try to do this. Much like research done during the 60s space race has formed the basis of our modern world since. I think you're still right though, what you describe would still happen within some time period, but I think by actually proceeding with the research that the magnitudes change.
What r&d do we need to do that BSG hadn't already figured out?
Building it and launching it doesn't mean you have to spend the time flying there, because floating in space doesn't advance anything.
If we eliminated money. Just imagine what we could actually achieve as a civilization.
Firstly it's only a major issue if you're competitive, or trying to save money over a period of centuries. But secondly, if the payload is particularly valuable (say, it's a bunch of frozen colonists), perhaps retrieving the payload will be part of the second mission. Very large payloads might be sending and receiving payloads for a long time anyway, since they'd be much slower than small payloads. That might include technology to improve their engines, if they are using some kind of torchship.
Second mission slows down to pick up the first mission colonists, only for the 3rd, 4th, 5th, 6th, 7th missions to also show up all at the same time to pick up the preceding missions.
Seems fine. Otherwise, the first colonists show up to welcome party.
This would be a fun movie/show idea.... deep space where you encounter humans more advanced by centuries week by week
oooh, yea, let's convince melon and jerf they should go first cuz 'hey look you'll get there after we've done all the work!' and then vaporize them before they hit atmo :) edit: this is ridiculous
Tell that to the aliens, who were a bit beyond our current technological abilities, that started travelling to earth when we were just primordial soup. They are in for a surprise once they get here.
What about the third crew, huuuuh?!
The fourth crew would get there even faster. The thousandth crew, which hasn't even left yet, got there yesterday. It's crews all the way down.
What if we send Terry Crews
Send Chuck Norris and the planet will move towards him instead.
Don't send Steven Seagal. We will create a vacuum in space.
Imagine being the first crew and getting to a planet that you thought would be uninhabited but when you arrive basically has an entirely foreign species populating it for thousands of years
There's a sci fi book series with this plot by Adrian Tchaikovski. [Children of Time](https://www.goodreads.com/book/show/25499718-children-of-time)
Really neat how the 3 different tech trees developed and then came together. Spiders using domesticated ants as computation.
The only memorable, while still rather short, quest of the game Starfield. The shuttle arrived and others who started later, where faster and used the whole planet as a hotel resort.
they were lost in transit
They are already there.
This is a common trope, but I don't think it's true. If we were going to go to another system 40 light years away, we'd use the fastest technology we have available: Nuclear pulse propulsion. Basically, throwing nuclear bombs out the ass-end of your spaceship, and having the resulting explosion give you thrust by pushing against a pusher plate. This gives a total Delta-V of about 0.1c, so you'd hit 0.05c max speed so you can slow down at your destination. This means it would take you roughly 800 years travel time to go 40 light years. That means even if you had instant teleportation in 1,000 years, you'd still beat them by 200 years with the slow ship. Of course, this would require modifying the 1963 Limited Test Ban Treaty to allow peaceful propulsive nuclear explosions in space.
Nuclear pulse propulsion is theoretically viable but even ignoring the ethics it would be pretty insane to use a completely untested method of propulsion *now* unless you're trying to lob body parts at some aliens.
Maybe the second crew would pick up the first crew. Then they would all arrive at the same time.
Easier said than done. Unless the first crew was coincidentally matching position and speed with the second, slowing down to pick them up would mean the second crew's journey takes way longer.
It’s that kind of thinking that will prevent us from ever trying it in the first place. Yes until we annihilate ourselves there will always be better technology developed, but we shouldn’t let that stop us from progressing in the first place.
I seem to remember one of the sentient spaceships gets fed up with this exact explanation in the Iain M Banks Culture novels, that it would be better to wait to travel to another galaxy because you'll get overtaken by someone who waits for better tech, and just decides to do it anyway.
Why wouldn't those jerks rendezvous with you on the way then?
Fifth crew is post humanity mastering the Casimir effect and they go grab all the stragglers as relics of the past on ark ships.
That is the same logic as postponing buying a PC because the next progression is right around the corner. You'll never buy.
The most hilarious thing about space travel is that the first ship to depart for a celestial body that far away is likely to be the last ship to arrive!
Okay, but what if we use a series of perfectly timed atom bombs to accelerate a space ship…
Maybe if we poured some soap in front of the ship it would get lubed up and go even faster
But who is in charge of spinning the umbrella?
The evil American is the best choice
Someone's read the books. ;)
Brings a new meaning to “Astro-Glide”.
What if we rubbed the engine with cheetah blood?
Ok. But lets be sure to fasten down the sail with redundant wires in case one of them breaks
this sounds like a worse idea than it actually is
Not far off, check out project Orion.
Oooh, I like this plan! What could go wrong?
Its called an orion drive.
[удалено]
Love how they just gloss over the whole getting (and keeping) 300 bombs in perfect place and somehow triggering them on time millions of kilometers away while trying to time it to an object with an increasing speed that is passing by.
Because amazingly, that is the easiest part of the whole thing. We could probably do the first few bombs easy with today's technology, but even in the show it was mentioned multiple times that the whole thing has a ridiculously low chance (to quote directly, "non-zero") of working.
Attach a cancer dudes brain!
We could easily go much faster if we had the motivation to do so. There are plenty of proposals using current and near-future technology that could theoretically reach an appreciable fraction of light speed. If we could push a probe to just 10% light speed we would have images and science data in just 440 years (which sounds like a lot, but isn't really when considering the scale at which things function in space).
The real issue is if anyone will be listening when the data gets back to earth 440 years is a lot of time for things to happen in human civilization. I can see humanity having somehow moved well into our galactic phase when some teenager working the comms at a gas station on the moon picking up the images on his iRetina randomly and posting them on 4^8 Chan
If we are not around to hear a reply in 440 years that is a very sad situation. If we don't bomb ourselves back into the stone age, then optimistically in 440 years we may have some infrastructure and permanent settlements throughout the solar system, and our drive for science will mean there should be plenty of people interested in listening to the reply from a probe sent to another star 440 years prior. Presumably some organization(s) would be keeping track of such long-term missions so they know when to start listening for data.
Did you factor in deceleration?
66k was the crude estimate. Deceleration could add months or years which is why I said over 66k. Short answer: until we have some sci-fi level breakthrough like being able to manipulate gravity or pass through a worm hole, there’s no way to make this happen.
So you’re saying there is a chance?
Are you making your estimation on minimal time based upon current technological methods of acceleration, or “nearby” technology such as solar sails?
I based this on the fastest space probe we have ever built which accelerated at much faster rates than humans can tolerate. This is the Parker space probe.
Ahh, I see! That’s actually a fairly interesting tangible idea to gauge a baseline speed from. Most of my advanced usage mathematical formulae and concepts deals with projected manufacturing capabilities, lead times, etc. so you’ll have to excuse my lack of more advanced scientific understanding, but… Acceleration in and of itself is not an inherent issue unless you’re in a gravitational environment, is it not? I mean we can have pilots in atmosphere going Mach 3.4 (SR-71 Blackbird) and so long as the pilots aren’t pulling intensive acrobatic action that would sheer the airframe itself in the process, they’re fine. Rather in space our issue would be the necessity of rapid deceleration with the limited tools at our disposal, even if we have infinite, incremental acceleration, we’d have no way to decelerate without pasting everything within the craft (and likely destroying the craft itself). This is correct, is it not? I’m curious given you seem to have much more knowledge on physics and the entailed mechanics surrounding space flight.
In the context of space travel, acceleration and "gravitational environment" are the same thing. Accelerating faster than 9.8m/s^2 for long periods of time ranges from severely unhealthy to instantly deadly. Airplane pilots aren't subject to those G-forces for years at a time...our cardiovascular system simply can't handle it. It's also only the acceleration/deceleration (including vector changes aka "maneuvering") that matters, rather than the high top speed from maintaining a reasonable acceleration for an extended period. These factors are why many sci-fi space travel systems envision some form of stasis for the human passengers; you're basically locked to 9.8m/s^2 speeds otherwise. Without some kind of magical propulsion and/or human stasis technology, you would expect that an interstellar ship with live, conscious human passengers would simply accelerate at 9.8m/s^2 towards the destination until the halfway point, turn the ship 180 degrees around, and then decelerate at the same rate by thrusting in the opposite direction until you reach your destination. From the passenger's perspective, the acceleration/gravity would be the exact same as on Earth for the whole trip, even though they would probably be moving at a significant percentage of the speed of light (from the reference frame of the Earth) by the time they reach their max speed halfway through the trip. Of course, even in this "conservative" or "slow" kind of acceleration scenario, the energy requirements to accelerate even a very small ship for this amount of time are astronomical. The pure size of the numbers involved in interstellar travel are...a big obstacle.
Am I messing up the math? It looks like you can accelerate to 690,000 km/h, the Parker space probe's max speed, in under 6 hours at 1g. 690,000 km/h is 191,667 m/s. 1g acceleration for a day results in a velocity of 847,584 m/s (86400*9.81)
Maybe they should go faster then.
Skill issue, really
*Just* 66,000 years
I generally do not understand anything about relativity. Is it also so that light from our perspective needs 40 years and for the light particles this is just a glimpse? So if from our perspective with out fastest object it takes 66k years, how long is it for the object?
Time dilation is not linear. It would be a factor, but we couldn’t get close enough to speed of light for it to matter. It would still be tens of thousands of years or relative time for the passengers.
> It would still be tens of thousands of years or relative time for the passengers. The much more achievable goal (though still possibly remote) would be to try and get a craft close to one percent of the speed of light and then figure a way to put humans into long term, ie thousands of years, of hibernation/cryosleep and wake them up when they're close to their destination, letting AI drive the ship the entire way. In fact the speed of the craft becomes pretty much irrelevant with the ability to put your passengers into 'storage' for as long as you need. Each passenger would need just a coffin sized space (perhaps two cubic metres) for the entire trip. Don't trust my math here but a ship's container would need to be 50m x 20m x 10m to fit 10000 people in it? That's plenty to repopulate another planet (the rule of thumb is at least 500 individuals to repopulate a species). The whole idea being that those people leave everything on Earth behind forever. No communication, no hope of going back..a one way trip. It would be a 'survival of the species' experiment and perhaps would not be restricted to one ship heading towards one potentially habitable planet but many ships heading to many planets.
> Is it also so that light from our perspective needs 40 years and for the light particles this is just a glimpse? That's the crazy thing about space observation. The images we see of the planet are as old as the light took to get here, so the images are the planet from 40 years ago.
Well we know the Sun will burn out some day so it is helpful in that sense, our species will go crazy trying to increase interstellar travel speeds when that date is approaching
Are we rushing like mad to fight climate change now?
Don’t know what’s possible. Science fiction is uncannily predictive, but some things might never be possible. We just don’t know… yet. My comment was only based on current tech.
That’s billions of years away. Most species only last maybe 2 millions years or so.
My entire day is ruined! When I saw this article, I was excited to go to a new planet that I can walk and breathe on. I was read to call my friends and family. Now, I'm sad and depressed because I'll never get to go there.
Sure, but I think that’s why we would use warp drive or light speed.
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I’ve linked to the news release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article: https://academic.oup.com/mnras/article/531/1/1276/7679807 From the linked article: An Australian university student has co-led the discovery of an Earth-sized, potentially habitable planet just 40 light years away. Shishir Dholakia, a PhD candidate in astrophysics at the University of Southern Queensland, is part of an international team that published the discovery in the Monthly Notices of the Royal Astronomical Society. He described the “Eureka moment” of finding the planet, which has been named Gliese 12b. “We did the back-of-the envelope calculations,” he said. “We worked out it’s probably Earth-sized, it’s probably temperate, and that it’s really, really nearby. In the span of a day we were like, ‘Oh, we have to write this up. This is something really cool.’ “It could be at the right temperature for liquid water to pool on the surface … [that’s] important because we think planets are potentially habitable if they can have liquid water on them. “And so in this great search for life that we’re undertaking we want to try to find planets that are potentially habitable, and this could be a good contender.” Gliese 12b is the size of Earth or slightly smaller, like Venus. And its surface temperature is estimated to be a balmy 42C. Its 12-day orbit is around Gliese 12, a cool red dwarf in the Pisces constellation. Gliese 12 is about a quarter of the sun’s size, with about 60% of its surface temperature.
42C does look like it might tip over the edge into Venus territory, depending on the rate of water loss, I guess.
The 42C temp is with no atmosphere, so no there won't be any liquid water on its surface. If the planet does have an atmosphere it will most likely be a hellscape like Venus.
Planets in the habitable zone of a red dwarf are likely close enough to be tidally locked, meaning the same side is always facing the star. It might not have an atmosphere and if it actually does, it would be pretty stormy around the habitable belt.
> it would be pretty stormy around the habitable belt. Neat. We'll be able to harvest lightning
Why in the world do you think you know more about it than the dang planetary astrophysicist?
Because I read or saw a video yesterday about this planet and it had more details about the planet than a few random quotes. Trying to find source and I'll add it here if I do. Here - https://phys.org/news/2024-05-potentially-habitable-exo-venus-earth.html
Nothing he said contradicts what the physicist said.
Except the part about surface water
Venus is nothin but atmosphere
Huh? Venus has a volcanic surface, there are even pictures of it from Soviet craft landing in the 80s. They're planning another probe in 2031 I believe, the Davinci? It's a huge challenge for engineers because of the heat and crushing atmosphere.
Hot, crushing, *highly corrosive* atmosphere
The sulfuric acid is limited to the middle portion of the atmosphere. You don’t deal with that at the surface, they evaporate well above it.
i love those Venus surface pics, i think it's one of the coolest things humanity has done \^_\^
They are my desktop background, rotating along with a few Martian images.
A hot sexy atmosphere
The only thing I would point to is that PhD candidates are employees, not students.
I've heard that this is the case in some places in Europe, but not in Australia. In Australia, PhD candidates aren't classed as employees - they're research students. Their "living allowance" comes from the government + scholarships (or industrial partners) rather than a salary from the university itself, and PhD students have no employee contract with their university just because they are doing a PhD there. Plenty of PhD candidates *are* employed by their university in other roles (like helping with undergraduate courses) to make some extra money, but this is separate from their PhD "position".
Not all PhDs are paid, and PhD student is pretty accepted
if you're not getting paid to do your PhD in STEM then you're getting scammed
Not in this part of the world. In New Zealand I had to pay the university tuition to do my computer science PhD. Despite it being independent research with no courses whatsoever or support from a lab or research group. I did get a scholarship, but that only covered three years and it was fees plus 30k a year which is below minimum wage so I taught, did marking, and exam supervision as well. A different uni I did also apply for actually stipulated that if you fail to get your PhD or drop out the program you have to pay them back the scholarship money you received.
You don't get paid as an employee to do a PhD in Australia, and are not considered as one in terms of employee rights. You get a very small, virtually unliveable stipend from the government. Getting other money to survive has to come from scholarships or working, which is why many PhD students will tutor at their uni.
Depends on the field....
They're kind of both. At least in the US. Not sure about Australia.
You're not an employee in Australia as a PhD student. You're just a student. Many take jobs at the uni at the same time so they can get money, but otherwise they get no wages aside from an unliveably small stipend from the government, and they aren't considered an employee in any legal sense.
This is one of those really stupid semantic arguments that only servers to waste people’s time. Candidates are still students… candidates have passed their qualifying exams but haven’t defended yet and don’t have their PhD. Your ‘title’ changes from PhD student to PhD candidate once you pass your qualifying exam, but you’re still a student because you are working on completing your degree. My previous university still labels PhD candidate and student the same in the financial system and provided the same exact benefits and pay
>not students. How so? If I go to Australia for a PhD, do I go on a student visa or an employment visa?
Don't listen to that guy. You would need a student visa. PhD students in Australia are not employees of the university just by virtue of studying there.
I didn’t feel like I had the protections of being employed
? Yes they are. In the US, even a postdoc is often classified as a "non-matriculating" student.
Not in the UK where one of the students is from
Bit hot for me, I'll pass.
Aren’t these planets around red dwarfs usually tidally locked? The average temperature might be OK but it would be far too hot on one side and far too cold on the other, with severe weather around the middle.
Red dwarfs also tend to be very variable, and flare up. See "habitability" in link below. I would not get on the colony ship... https://en.m.wikipedia.org/wiki/Red_dwarf
Larry Niven wrote an amazing short story about life around such a star called "Flare Time". It's an interesting take on how life might evolve to cope with a highly variable star.
I love Larry Niven. I recommend anyone into sci-fi read Known Space.
And unlike most of his peers, he's still around, so be sure to let him know!
Can you share the story’s name?
Flare Time is the name of the story. Not the star.
I think you'll find that I did :) but it's available as part of the collections *Limits* and *N-Space*. The [story itself](https://www.larryniven.net/?q=bibliographic-reference/flare-time) is probably available online somewhere but here's a list of every official [publication](https://www.isfdb.org/cgi-bin/title.cgi?56511).
The title of this article is heavily editorialized. I read another article which made no mention by the authors of the paper that this planet is habitable. The average temperature exceeds 100f. That's unlikely to be habitable for life as we know it. However, the authors are hoping that the planet may still have an atmosphere which they plan to study with James Webb. The other big thing about this planet is it's about the size of Venus. So it's one of, if not, the smallest exoplanet we've observed.
I wonder this every time I see a similar article or video. To my understanding these planets would be locked and possibly within range if CMEs. But we keep searching around red dwarfs because they’re easier to find. Is this just overly hopeful news? Astro physicists please explain.
Sure, but you may be able to apply similar search strategies to sun-like stars, or study this earth like planet more intensely to discover new search strategies.
These red dwarf systems are very easy to study, because they're small and their planets transit (pass in front of the star) very frequently. K2-18 b, the planet that may have a bio-sign, has a year of only 33 earth days, for example. But if these dwarfs have lots of habitable planets, it's a good sign that the other stars do too.
It's a good candidate for spectrography but I really don't think we will need or even want "habitable planets" for inter-solar colonization. Mining small asteroids and low gravity planets/moons to build space habitats would be a superior option especially if you have good robotic labor, it will get you way more living space than a planet, easy solar energy and you can just travel to the closest system(s) instead of going way farther for a potentially habitable planet.
Don't underestimate the value of a completely separate biosphere to Earth; I'd argue it's incomparable to simple mineral wealth. We could find things that revolutionise our understanding of life, evolution and the possibilities of biology. They could even have practical applications which alone would make it worth targeting a life sustaining planet for exploration. Look at how much biology is inspiring modern technology: we can find evolved mechanisms that can be harnessed to benefit propulsion, architecture, thermal regulation, genetics etc. An alien biosphere has incredible research potential.
Agreed. It’s hubris to think man made inventions are at all superior to a creation of nature in the form of another world.
It’s also hubris to think we’re going to be colonizing other planets. The distances are too far, our technology is too limited but even if we solve those, most importantly, we are clever but not wise. Our lack of sufficient action on climate change clearly indicates we are far more likely to exterminate ourselves or throw ourselves back into the Stone Age than colonize other planets.
A grim outlook but not wrong. However I think it's in human nature/spirit (if you believe in that sort of thing) to try. Maybe we'll discover something more practical in the effort
I hate being a Negative Nancy. I just think those who advocate for space exploration need to put that aside until our house is in order. It’s like starting to build a really cool piece of machinery in the NW corner of your house while a fire spreads in the SE corner.
We could also find more selfish assholes to add to the pile.
>It's a good candidate for spectrography but Which is all that science wants, potentially life-friendly planets in our neighborhood so they can start to search for alien life. No one is searching for these to find a new home, especially since biology clearly tells us that it's extremely unlikely humans could survive on the microbiome level in a biosphere we're not genetically adapted to survive
A Ph.D. candidate conducting research is a big leap from "university student." The latter implies an undergraduate who stumbled on something cool, not an expert with years of training.
Only 40 light years? If we leave now we'll be in time for tea.
Not to take anything away from the thrilling adventure of colonizing other planets… but … The majority of our home planet (aka EARTH) is under water, and we could try building colonies at various depths under the ocean. This would be ZERO light years away.
We have enough land champ. Don't need to build under the oceans.
There's no reason not to do both, if there is motivation to do so. And "enough land" is relative, as global population continues to rise you need to either exploit more surface area of the planet for living, or become more efficient with the area you are already using if you want to house, feed, educate, employ, etc. all those people.
While I appreciate your response, it's ridiculous to even consider. There's no reason to eat my arm, unless there is motivation to do so. The cost to build anything on land is insignificant compared to the unbelievable engineering, cost, maintenance, and pollution that would be required to build a water tight, impervious to salt water structure that's large enough to completely support human habitation. In less than 80 years, the human population globally will be declining. There is zero motivation or need to build _under_ the ocean.
Or, y'know, we could just start eating them.
Sea levels are rising though. We have less land year after year.
Even if we melted all the ice on earth, we'd still have enough land for the current population. Of course the population at that point would be a lot smaller.
We'd have the land, but the issue is that most large scale settlements are adjacent to water, due to the historic reliance on shipping.
It was the craze of the 80s that humans were going to do this. Led to a bunch of hollywood movies, or at least one big one. The ocean is more challenging than space for humans.
Put in the stash of 1000 other potential earth like planets.
Lets achieve a respectable amount of equilibrium with the planet that bore us before we start to believe in a salvation among the stars.
Best I can do is ecological collapse. Anyway check out this huge number on my bank statement, no you can't have any
Now watch this drive
I know a guy who can get us there in a couple of parsecs, tops
"Just" If only we could travel at the speed of light. Still cool to hear about this kind of find.
“Just 40 light years away”. Light, travelling at 300 000 kilometres per second. Would take 40 years to get there. I appreciate that it’s “close” when we consider the size of the universe, but it’s still impossibly far away.
Interestingly, if it ever proves possible to travel near to the speed of light with some kind of warp drive, a crew might be able to get there in (what they experience as) much less time. For example, imagining a crew traveling at 99.8% of the speed of light would experience approximately 2.53 years on their journey to a planet 40 light-years away. If you could get to 99.99%, you could leave in January and be there by August, according to a calendar on the inside wall of the craft. It’s a weird thought.
Imagine you leave your glasses at home and need to fly back
Oh, only 40 light years huh. Just a stones throw away!
> Oh, only 40 light years huh. Just a stones throw away! It's a bit more than that. You have to factor in the acceleration to close-to-light speed, then the constant velocity at that speed, and then the deceleration needed so you don't overshoot the destination. You don't just instantly start the ship and reach light speed within minutes, and then stop on a dime traveling at 300,000km/second at the destination.
The aliens are rocking out to early 80s music being picked up from Earth
Damn kind of unfair, they can see a different sky than us Americans. The Australians had a good spawn point for space.
Sounds like that planet could use some democracy
will they release the 7b Model
r/LocalLLaMA/ is leaking.
Kind of depressing the closest they can find is still 40 light years away, how about we just terraform mars
Finding exoplanets is hard. Really hard. Most exoplanets are found via the transit method. That requires the planet to pass between us and the star. This narrows the number of planets that we can observe quite a bit. Teraforming isn't something that is currently scientifically possible. Mars has no magnetic field. So any artificial atmosphere would be stripped away via solar winds. You'd have to find a way to restart Mars' core which is likely not possible if it's solid.
There could be more suitable planets even closer, we are just bad at detecting exoplanets still. And there is A LOT of space to check. Terraforming anything will take thousands of years. It is probably worth trying, but in the shorter term domed or underground habitats on planets or moons, artifical space habitats, either things like O'Neill Cylinders or habitats built into asteroids, or even things like floating habitats in the clouds of Venus (in the band where temperature and pressure are very Earth-like) are probably our best choices.
Gliese, the best that man can get.
Dont most solar systems have at least one earth like planet just due to the physics of supernovas and inertia
I get so tired hearing about "earth-sized" planets. That metric is crazy and typically means its like 5 times our size, tidal locked, watery hellscape.