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Close and tranquil solar system has astronomers excited (nasa.gov)
101 points by olvy0 on July 4, 2020 | hide | past | favorite | 108 comments



Just for context, there are 22 other solar systems within 12 light years of us.

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


"Mr. Data, report to the stellar cartography and prepare a view of sector 001 and all stars within a radius of a few parsec."

Here is a map: http://www.atlasoftheuniverse.com/12lys.html


Please just make JWST operational at last, please.


I've always been curious, when the design phase ends and construction begins, wouldn't new technologies have emerged by then? Do they try to keep up and incorporate improvements or are new breakthroughs rare?


After 25 years in the making and now waiting to be launched, technology of course has advanced enough for JWST to be "obsolete" in that sense by the time it's operational. However, new space telescopes take so long to be operational but they still give us amazing data... even if what they give us is peanuts from old dusty tech it's still worth it. Anyways, JWST is going to be incredible... heck, even after so many years Hubble still produce a ridiculous amount of good data and research and it was designed in the 70s! Can you imagine if launching was cheap and we had a constant flow of budget for space telescopes and we could launch a new improvement every year (after an initial ramp-up of, say, 10 years)? Unfortunately launch costs and cadence has been a major blocker so far to the things you asked about IMHO.


Just wait for Starship. It promises all that, and the possibility of an eight-meter aperture.


Launch cost have been going down recently, so hopefully that won't be a problem in the future.


Unfortunately the JWST isn't a visible light telescope — it's sensor is for infrared light [1]. It's not going to be providing images like Hubble did, as it was designed to look at extremely far away galaxies and nebulae that have very redshifted light.

[1] https://science.howstuffworks.com/jwst-infrared.htm


The idea related to the OP is that JWST can actually image distant exoplanets without depending on spectrum and/or transit analysis like it's done today. In a way, JWST will be able to give us visuals of exoplanets we only dream about today, much like what Hubble did for some objects previously only imagined. At least that's how I understand what JWST can do for exoplanets hunting.


With launch cost falling by orders of magnitude, I hope for a new era of many smaller, more specialized space telescopes.

Not sure if that is how it really works though :)


What is JWST?



James Webb Space Telescope, I guess


We still don't know:

1. If those planets have water. 2. If their surface gravity is tolerable. 3. What kind of atmosphere they have, if any. 4. What's the mineral composition of those planets. 5. How violent the surface weather is, provided an atmosphere does exist.

So, there's only cause for cautious optimism.


[flagged]


Please don't do this here.


What's special about November?


There's a guy in the White House who badly needs a success before then, seems to be what the GP was referring to.


Not how I interpreted it, the guy in the White House does not get a success, those on the ship need an escape for if the guy wins in November.


Ah right, thanks. EDIT: I'm confused that you got downvoted, your explanation was helpful to me.

Anyway, with this out of the way I'm happy to report to GP that there's places that can be easily reached from the US with current spaceship technology[0] where Trump does not rule and where politics is less polarized.

[0] or current bus technology if you're on a budget


Since Canada and Mexico just closed their borders to the USA I think it just got a lot harder to flee.


Canada has been closed since March 21 and only one Mexican state closed their border with Arizona. Just FYI.


Musk ever spoken about what he'd do to get outside of the solar?

Speed of light is a bastard of a limitation to have to beat...


As far as we know Musk isn't keen on the idea of interstellar travel.

SpaceX's COO Gwynne Shotwell is, and has spoken publicly about it (and has allude to Musk's opinions on it [1]). That said the basic requirement is a significant propulsion breakthrough [2], current technology just isn't good enough.

You don't beat the speed of light, you just travel at an appreciable fraction of it an accept the fact that by the time you arrive everyone on earth will have aged n (>11?) years.

[1] https://www.ted.com/talks/gwynne_shotwell_spacex_s_plan_to_f...

[2] https://twitter.com/thesheetztweetz/status/11877454453611806...


I think the first strides in interstellar travel will probably occur once long-term habitation and manufacturing in space have been mastered, because then it's feasible to construct ships that are either too large to drag out of a planetary gravity well and/or too dangerous to build in the gravity well of an inhabited body (nuclear propulsion).


Another thing is that human lifespan might well improve in the meantime. Pair that with deep sleep/suspended animation and you have a pretty potent combo for conquering long distances.


In the near future, human lifespan might improve, but mostly in the form of surviving in poor health at old age.


Only for those left behind, time dilation is magic.

As per wikipedia: > a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime

So it's really only a challenge of propulsion. You're not making a return trip to any recognizable civilization though.


  > only a challenge of propulsion
Also a challenge of ablation. At any reasonable fraction of c your spacecraft has a serious erosion problem.


Possibly also the challenge of getting baked by the Unruh Effect.


Yeah, but have you ever worked out the rocket equation for a spaceship that accelerates at 1G for a full year? There literally isn’t enough mass in our solar system, even with a ridiculous engine with an ISP of 5000 and perfect alchemy to convert all raw mass in the solar system to rocket fuel.


Project Orion could do ISP of 100,000. Even nuclear thermal engine could reach 5000


As far as I know Nuclear Thermal rockets have topped out around 1000. Project Orion is entirely theoretical and the ISP calculations should be taken with a grain of salt.


The amount of energy required to keep that 1g acceleration though...


Sun have lot of energy, so it can be used as energy source. If you plan to travel at % of c, you will need strong enough radiation and thermal shield anyway. And if you have such shield, why not just dive into Sun for refueling? Humans can stay at high orbit, when interstellar locomotive refuels.


At the speed you are going, the sun will quickly be a pale white dot


Locomotive can harvest energy and matter from Sun and then use it to orbit around Sun, slowly gaining speed, until it will no longer will be able to compensate сentrifugal force. Then it can reach high orbit passively, pickup pilots on high orbit, and be ready to flight, with full tanks. Or it can dump fuel, and do another dive to Sun, for more fuel.

If it will survive Sun radiation at low orbit, then it may also survive interstellar travel at high % of C.


Potentially you could bring the sun along with you.


Where does the energy to accelerate the sun at 1g come from?...



The sun is _really_ _really_ heavy.

From that article the best case scenario is a billionth the acceleration you are looking for. And you can’t take a billion stars because then you have more mass...

Edit: the interesting part of discussing the 1g is probably less a realistic proposal and more how about how the concept of acceleration quickly runs up against our mental constructs of what acceleration and distance means. I don’t know the source, but it’s probably an enlightening to discuss what it means in the context of relativity.


Ok, it would be exciting to move the whole solar system to a nicer place in the galaxy. But how many years are we not going to use to evaluate the ethics and technical risks of the experiment? :)


From the sun itself, potentially it might be doable


Particles accelerate to light speed all the time though. So it is possible, we have not yet discovered a way to do it at larger scale.


> Particles accelerate to light speed all the time though.

No, they don’t, as far as we know.

There are particles that are always slower than light, and particles that always go at exactly light speed, but no particles that accelerate to (or decelerate from) light speed.


"Particles accelerate to light speed all the time though"

No.


Particles also don't care so much about how quickly they stop...


“Speed has never killed anyone. Suddenly becoming stationary, that's what gets you.”

Jeremy Clarkson


Explored in Paul Anderson's novel Tau Zero. https://en.wikipedia.org/wiki/Tau_Zero


Nitpick, it's Poul Anderson. Yes, that is an odd spelling of his first name.


Not in Denmark where his family came from.


Brilliant book! I recommend it highly.


And you're also never stopping anywhere, so it would only ever be a permanent sight seeing tour.


This substitutes the challenge of inventing a warp drive with the challenge of inventing a limitless free energy machine. An antimatter fueled rocket can't keep up with what "1G, indefinitely" demands. Not even beamed power propulsion driven by a Dyson swarm can do that.

I like the Revelation Space universe, but its fictional Conjoiner drive and the near-light-speed Lighthugger spacecraft powered by it are no closer to realization than any of Star Trek's technobabble. The same goes for the forever-accelerating Bussard ramjet vessel of Tau Zero.


> a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime

Wow that is actually very fascinating, it never occurred to me that it works that way. I’m always thinking of 11 light years as too far away for someone to achieve in a lifetime, but I am of course thinking about that from the perspective of the person who is not traveling.


I'm not sure how they calculate the 1g thing past the speed of light (which takes you something short of a year to get to by classical mechanics). But say we just break physics as we know it, and somehow the prophesized amount of time to travel is accurate. You're still going in a straight line and not stopping, unless you want to take another lifetime or be crushed by forces that would hurt just a little bit.

So don't turn, only decide to stop in the first half of your life (or you won't live to see the end of the journey), beat light and physics by the end of year one of your life, and enjoy the ride. I'm not sure what you'll "see" outside of your spaceship though, and I do hope for you that there's not a single speck of dust in your path and no wall at the end.


I didn't read their idea, but you wouldn't ever need to go faster than the speed of light for this to work -- just approaching it infinitely close would be enough.

Sure it might take a hundred million years for your journey from an observer watching you on earth, but thanks to time dilation, it could still be less than a lifetime for the person on the ship


Well then how do you get to the parts of our universe that are receding at a speed faster than light due to space expansion? I'm not nearly as comfortable with relativity as I'd like to be, but too much in this hypothetical "woahdude" scenario ends up being a logical roadblock to me.


Stopping is sort of a problem.


what is one human lifetime? that seems an uncertain measure. Also most astronauts I've seen look like they're halfway through one human lifetime when they first get off planet.


There is plenty of stuff to explore and colonize in Solar System alone. But interstellar travel is not that unfeasible.

Sending an unmanned probe to Alpha or Proxima Centauri might be just possible in the next century.


We can send probe right away by throwing few dozen billions on it, but it will arrive in the next century.


So realistically we have two ways of colonizing this. Either we cure aging so a few decades of space travel wouldn't make a dent in our life and our physical ability to colonize an uninhabited environment OR we invent real AI and leave space colonization to the machines as they have both don't age and can transport themselves at the speed of light.

I'd say machines will be cheaper.


Rather than curing aging (about as likely as interstellar human travel), it could be a ship capable of supporting multi-generational passengers.

11 years at light speed would still be 100s, 1000s of years at speeds obtainable by humans. Building a ship capable of that kind of life support is just beyond capabilities. A ship of that size is not getting off the ground. Our current manufacturing capabilities outside of the gravity well is assembling modules together or maybe a 3D printer


Here I think aging is far easier to tackle. Aging is a discrete set of biological processes that we understand more every day. The bounds we need to make in science are not so extreme to defeat aging, a process we have a pretty good view on now. Interstellar travel requires significantly more leaps. Light speed travel, or some big fraction of light speed [and slowing down from light speed]. It requires a huge amount of engineering and physical resources to even contemplate. It will take a concerted effort by a nation state. Aging is something that can be tackled collectively by the nations of the world, and just gets better understood every year naturally. Just spit balling this some, but that's roughly how I see it breaking down


>It will take a concerted effort by a nation state.

It will take a concerted effort by our species. Just as you go on to say that solving aging would require multinational support, why would you limit interstellar travel to a single nation?

The fastest way for us to become space voyagers would be for us to receive that signal from somewhere near Vega that tells us how to build the machine to take us places.


Well I don’t limit it on purpose. But the idea of nations cooperating right now seems a little in the future. Whereas with aging, science will just naturally progress. No changes required to the current cooperative structure. It just happens because that is how science goes. Space is just much more political than biology.


yea exactly, we are naturally incentivized to cure aging. With about 10% of the worlds GDP spend going to healthcare you'd expect us to get there eventually.

Right now the voyager is traveling at 17 km/s which is 0.0056% of the speed of light. We don't have the propulsion technology and given the known laws of nature, it's unlikely we will ever have something feasible to travel at 10% of light speed. But even if we did manage that we'd be looking at 100 years of travel for a one-way trip.


What fraction of c is achievable in near future (say next 20 years) with humans and w/o humans?


Without humans, 20% is achievable in the very near future.

Payloads would be measured in grams, though. That's what Breakthrough Starshot [1] is all about. Given suitable infrastructure (e.g. lasers stationed across the solar system), even 1/3 c is possible for machines.

Crewed missions would be seriously limited given near future technologies - the craft would simply be too heavy for using solar sails and even nuclear thermal propulsion only gets to a tiny fraction of c.

Also keep in mind that you need to slow down at the target, too, if your mission is crewed as fly-bys like Breakthrough Starshot aren't desiderable for crewed missions.

The cold hard truth is that your ΔV = 9.8 * ISP * ln(MR), where MR is the mass-ratio and MR = (Mass[Propellant] + Mass[Spacecraft]) / Mass[Spacecraft].

ISP and MR for known near-term propulsion systems are as follows:

• Chemical rockets: ISP <500s MR ~10 => ΔV < 11 km/s

• Ion engines: ISP <5000s MR ~2 => ΔV < 34km/s

• Nuclear Thermal rockets: ISP <15000s MR ~2 => ΔV < 102 km/s

• Multi-stage ion engines: ISP <25000s MR ~2 => ΔV < 170 km/s

So basically the fasted currently known option that doesn't straight up use nukes + pusher plate can get you to 0.5% c give or take.

[1] https://en.wikipedia.org/wiki/Breakthrough_Starshot


I don't think we have any plans of building anything testing speed in that time frame do we? New Horizons was/is(?) the fastest we've made, and it is pretty much end of mission as it's not going to approach anything interesting in any near generations' life span. Powering a craft is to me the biggest hurdle. Solar won't work for the obvious reason we're trying to get away from a star. Even a nuclear power source could only deliver so much power


Using AI seems pointless. Not to mention that what need would an AI have for a planet. Might as well put a solar sail in our system. Maybe make a few thousand clones...

How about sending a whole village for the voyage? Some will die, some will be born, culture will be thought and the next generation would colonise the new planet.


Send a bunch of frozen embryos piloted by an AI, then fertilize them in 2-3 batches 40-60 years or so prior to arriving so that you have 2-3 generations of people, the first of which are trained by video / VR / interaction with the AI.

Have a few cuddly dogs aboard too so that the first generation doesn't grow up completely devoid of affection by only talking to machines


The engineering complexity of this is orders of magnitude higher than curing aging.

In this case you have to fully automate healthcare and education. Then you still have to steer these individuals towards some sort of economic goal because presumably you are not just sending kids to a foreign planet for fun.


It sounds hard, but might not be orders of magnitude harder than impossible.


I think we'll get to cure aging eventually, mankind has been investing in extending life very consistently (a quick google says we spend about 10% of global GDP on healthcare).

It may take a very long time to get there though, but I don't see any reason why people would stop funding progress towards this goal.

Compared to that, what investment is going towards automating childcare, education and healthcare today?


That healthcare spend is not medical research, most of it is ruitine medical procedures like treating someone's broken rib. That's like taking all of global spend on IT, motors and robotics and claiming thats our automation research.

It has no bering on making us live forever, and I am willing to bet that 'curing' aging for good is impossible unless we figure out brain uploading, which could be impossible and opens a new can of worms - is the new copy actually you?

By contrast we are making a massive investment to automate more or less everything, for instance advances in robotics and machine vision clearly help to automate both healthcare and car assembly.


A fun book about this idea, Kim Stanley Robinson's Aurora.


Similarly, Red Mars by the same author takes the much easier goal of colonizing mars!


I just read Aurora about a month ago. Loved it. So much in it. A great not-evil self actualizing AI, an unexpected story arc. Beautiful book.


Why pointless? Assuming real AI are incorporated into our economy this would be a classic case of comparative advantage.

They could operate mining facilities on these planets and live to see the profits of a big mineral haul back to earth.


You should read the Bobiverse books, they’re exactly about this with a lot of geeky humor added.


I liked the start of the first book very much, but then it started to get repetitive and after the second book I decided to skip the third.


I really enjoyed the audiobooks of these, which on the face of it ought to have been tricky, voicing dozens of copies of the same person.


Realistic should take into account required time, tecnology, biology, culture, politics and economics (just to name a few).

Taking out of the map colonization, and trying a very long term (decades, or centuries) plan to send something like the Voyager or even the Mars Explorer just to learn what is there is more realistic. And once we know more decide what are the next realistic steps. But think in hundreds or thousands of years if everything gets right.

In our current stage it would be easier (not easy) to colonize Venus, the moon or the asteroid belt, and could have a more realistic time frame.


I agree current solar system would be easier to colonize and definitely economically more sensible but I do think that when lifetimes expand to be 100s of years, that the timelines on what you can invest in would expand accordingly.

For example, the longest timeframe in pension fund investing is 25 years. Which is 1/3th of a lifetime.

If lifetimes increase by 10x then the timeframe would become 250 years and mineral explorations of other solar systems becomes a feasible financial endeavor.


The idea of travelling to another star in a little ship that is launched from earth and is barely able to make the journey is both a very bad plan and a persistent trope. I dont wan't to travel on a wing and a prayer.

You have to have a large space industry, mining and construction, to be able to build large ships and send autonomous drones, supllies, etc. You would do that ahead of any colonists actually arriving.


"The Songs of Distant Earth" by Clarke had a sorta-third option, where we sent out ships with just frozen embryos, and some automation which in theory kept infants alive long enough to watch videos / and other automated "parenting" material to get them to adulthood and kick-start civilization.

Of course... this was to avoid an extinction-level event, is assumed to have failed on 95/100 attempts, and was even in-universe acknowledged to just be the best of a number of catastrophically bad options.

But, a sorta-kinda solution.


That's a pretty solid idea actually. Have robots build everything and then grow the people as the last step. This could actually be doable in this century with continued incremental improvements in computing and robotics, which we're already working on. No need for propulsion breakthroughs or hypersleep. From the perspective of people on earth, it doesn't matter that much because it's such a long term project that no-one will be alive for both the launch and the landing anyway.


We can just send seeds, and in just few dozen million years they will form new civilization. It's dirt cheap.


Why do we need to cure aging? Humans have already been hurtling through space for over 100,000 years. We just need a way to continue that streak, but headed in the direction of a new solar system.


The third option is to just have multiple generations live and die on the journey to getting there, with which ever generation is alive at the end colonizing the planet.


True, that's even more expensive though cause you need to cary the full spectrum of educational and healthcare institutions onboard


Very high probability they all kill each other onboard


It's not actually a thing, and has never happened historically, at least not that i could find. Even widespread crime and civil wars don't result in 'they all killed each other', and no war ever killed even 30% of the population.

There have been many isolated communities and if they die, thats because they succumb to diseasse or disaster.


How would there be a historical record of a community that killed itself entirely?

Also, all these historical examples occur in the context of having millions of acres to roam, probably access to a lake or ocean, sunshine, fruits, seeing other animals, and so on (the natural habitat of humans). Even in prison they get yard time, and prisons are extremely violent.

The number of generations it would take to travel ### lightyears away is so high that _something_ is just bound to happen. What if one of the generations gets hooked on bath salts? What if they get irradiated and lose fertility? What if they start a cult? What if there's a lone wolf killer who takes them all out?


Obviously there are tools, books, houses and buildings. A civilisation doesn't just vanish, it leaves a mark on the world.


You can also "just" make a fast enough ship and get there in 10 years, o 1 month, from your perspective at least.


Travelling 11 lightyears in 10 years would require faster than light travel, which last time I checked is impossible in this version of the universe.


You are talking about time in a frame at rest at either endpoint, not the frame of the ship/passenger, which relative to the rest frame is experiencing time dilation.


ok, if we can have breakthroughs in propulsion (and braking) then that would be possible.

My understanding is that acceleration gets exponentially more expensive at higher speeds making it practically unfeasible to build a ship like this


> My understanding is that acceleration gets exponentially more expensive at higher speeds

Asymptotically approaching infinity as you approach light speed, not merely exponential.


> and can transport themselves at the speed of light.

Since when is this possible? Did I miss something?


AI can be copied and all its state transmitted, this is actually one of the biggest gamechangers towards human brains.

Suppose you have a real AI inhabiting a robot here on earth, it would only require to copy the AI, transmit it and boot up the AI on compatible robotics hardware on the new planet.

This would be the equivalent of transporting your brain into a cloned body.


Via radio signals. It’d still require a ship flying there though, but that wouldn’t have to be built to support life.


exactly. you'd have to send a ship with all the robotics and equipment but there's no need for intelligent beings to lose conscious time during this period.

Although at this point you (=the AI) would lose 11 years transmitting yourself, you won't actually be conscious of this process.



Can we just accept habitable zone planets exists in every single star system around us? Thanks.


No, because there's no evidence that's true. We've found lots of stars with planets around them where none of them appear habitable.




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