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Earth-like planet spotted orbiting Sun’s closest star

nature.com

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Re: Earth-like planet spotted orbiting Sun’s closest star

#41

Post by Udo »

74B5 wrote: post #32
Udo wrote: post #21

Earlier quoted context omitted.

I find it enjoyable to think about the technologies that might just be in the cards further into the future. If we ever figure out light-weight fusion drives, we could build light hugger space ships that accelerate to a decent fraction of the speed of light. At 1g acceleration it takes about one year to get to 0.9c, which would make the Proxima system accessible with a travel time of about 6 years. Or 8 years at 0.5g…

Thank you for your optimism, now let me balance that out a little. Propulsion maybe the easier part of engineering. Afaik we are nowhere near to life support and environment control that could be considered stable for a time period of maybe 10 years or more. The biggest biological advantage, adaptation is meaningless for large organism on such a timescale and maybe dangerous on a microbial level.

You are correct that we are nowhere near that in life support technology, however, there don't seem to be an fundamental hurdles there. If we end up opting for a biological life support system, adaptation would not even enter the equation - it'd be a matter of genetic engineering. An obvious danger would always be onboard ecosystem collapse, of course.

Re: Earth-like planet spotted orbiting Sun’s closest star

#42

Post by rmbyrro »

Udo wrote: post #21
NeoTar wrote: post #15

Another point for anyone considering whether we should send a space-probe there... The current fastest man-man object is the Helios 2 space-probe, reaching something like 25 000 kilometres per hour. Proxima Centauri is 1.3020 parsecs away from Earth. So, just diving one by the other, we'd looking at something like 18 000 years as a rough order of magnitude for sending something from Earth to Proxima Centauri. You'd b…

I find it enjoyable to think about the technologies that might just be in the cards further into the future. If we ever figure out light-weight fusion drives, we could build light hugger space ships that accelerate to a decent fraction of the speed of light. At 1g acceleration it takes about one year to get to 0.9c, which would make the Proxima system accessible with a travel time of about 6 years. Or 8 years at 0.5g…

This is exciting stuff indeed. Imagine a year-4,000 spaceship reaching Centauri before another spaceship dispatched 1,000 years before it?

For the cynical or pessimists: I'm not optimistic about humanity reaching year-4,000, I'm just possibilistic about it (as in the philosophical meaning [1]).

[1] https://en.wikipedia.org/wiki/Actualism#:~:text=possibilism,...

Re: Earth-like planet spotted orbiting Sun’s closest star

#43

Post by parksy »

EarlKing wrote: post #10
parksy wrote: post #4

Sweet let's crank up the generation ships. Of course picking a suitably inspiring name should be the first priority. Unity? Terra Nova? Gaia? On a more serious note is this a good candidate for JWST, would it be able to infer chemical composition from the planet's spectrum or something? Awesome though we went from (in my lifetime) learning at school that other planets have never been observed, to finding them sprinkl…

Before anyone gets too excited I'd just point out that all they have found is a rocky world within Proxima's habitable zone. That doesn't mean that world necessarily has a breathable atmosphere, water, sufficient gravity, a geomagnetic field, rotation sufficient to distribute heat equitably across its surface (as opposed to it being tidally locked facing Proxima), or any of a dozen other features requisite to support…

Yeah I was being a little tongue in cheek with the excitement, still it's pretty crazy we're actually seeing and cataloguing exoplanets now which was still in the realms of science fiction less than half a century ago.

Anyway if Stellaris has taught me anything it's that the flares will add additional energy credits to the system... what's not to like?

Re: Earth-like planet spotted orbiting Sun’s closest star

#44

Post by rbanffy »

tokai wrote: post #23
rntn wrote: post #13

Sadly, as discussed here, the technical problems with propulsion systems for interstellar travel are non-trivial: https://news.ycombinator.com/item?id=29638529 Of course that doesn't necessarily preclude a nearby higher level Kardashev Civilization becoming interested in all the noise we're making and heading over. As we put up systems beyond Webb, it may be possible to observe a hypothetical inbound craft / fleet so…

I thought the nuclear propulsion options were viable and relative simple.

Even if you get a very high specific impulse, you still need to pack a lot of reaction mass. You'll also need a lot of supplies (or a biome) because even if you get to 0.1 c, it's still 40 years to get there.

Re: Earth-like planet spotted orbiting Sun’s closest star

#45

Post by yitchelle »

5350-uiop-1130 wrote: post #35
NeoTar wrote: post #15

Another point for anyone considering whether we should send a space-probe there... The current fastest man-man object is the Helios 2 space-probe, reaching something like 25 000 kilometres per hour. Proxima Centauri is 1.3020 parsecs away from Earth. So, just diving one by the other, we'd looking at something like 18 000 years as a rough order of magnitude for sending something from Earth to Proxima Centauri. You'd b…

>something like 18 000 years this is why we don't see any signs of life out there. there really isn't any point in trying to venture beyond your home. universe is just too big even at the speed of light when you start venturing beyond your local group.

I guess the assumption is their life span is similar to that on our planet. If the life span measured in thousand of years, it will be a different story.

Re: Earth-like planet spotted orbiting Sun’s closest star

#46

Post by bottled_poe »

rntn wrote: post #13

Sadly, as discussed here, the technical problems with propulsion systems for interstellar travel are non-trivial: https://news.ycombinator.com/item?id=29638529 Of course that doesn't necessarily preclude a nearby higher level Kardashev Civilization becoming interested in all the noise we're making and heading over. As we put up systems beyond Webb, it may be possible to observe a hypothetical inbound craft / fleet so…

With all the messages we’re sending I’m sure a curvature propulsion drive is just around the corner ;)

Re: Earth-like planet spotted orbiting Sun’s closest star

#47

Post by rbanffy »

5350-uiop-1130 wrote: post #35
NeoTar wrote: post #15

Another point for anyone considering whether we should send a space-probe there... The current fastest man-man object is the Helios 2 space-probe, reaching something like 25 000 kilometres per hour. Proxima Centauri is 1.3020 parsecs away from Earth. So, just diving one by the other, we'd looking at something like 18 000 years as a rough order of magnitude for sending something from Earth to Proxima Centauri. You'd b…

>something like 18 000 years this is why we don't see any signs of life out there. there really isn't any point in trying to venture beyond your home. universe is just too big even at the speed of light when you start venturing beyond your local group.

> even at the speed of light

If you get really close to the speed of light (which is not really practical from a materials engineering standpoint) your time of transit is significantly shorter.

Once these (extremely hard) engineering problems are solved, a trip to the next star can be a week-long affair from your point of view, but your friends back on Earth won't see you for about a decade.

Re: Earth-like planet spotted orbiting Sun’s closest star

#48

Post by rbanffy »

yitchelle wrote: post #45
5350-uiop-1130 wrote: post #35

Earlier quoted context omitted.

>something like 18 000 years this is why we don't see any signs of life out there. there really isn't any point in trying to venture beyond your home. universe is just too big even at the speed of light when you start venturing beyond your local group.

I guess the assumption is their life span is similar to that on our planet. If the life span measured in thousand of years, it will be a different story.

Lifespan is one thing, but also the "cadence" of life. For a mammal, spending a year in a spaceship is hard. For a brick, spending a thousand years as part of a wall is the natural order of things.

Re: Earth-like planet spotted orbiting Sun’s closest star

#49

Post by rbanffy »

rmbyrro wrote: post #42
Udo wrote: post #21

Earlier quoted context omitted.

I find it enjoyable to think about the technologies that might just be in the cards further into the future. If we ever figure out light-weight fusion drives, we could build light hugger space ships that accelerate to a decent fraction of the speed of light. At 1g acceleration it takes about one year to get to 0.9c, which would make the Proxima system accessible with a travel time of about 6 years. Or 8 years at 0.5g…

This is exciting stuff indeed. Imagine a year-4,000 spaceship reaching Centauri before another spaceship dispatched 1,000 years before it? For the cynical or pessimists: I'm not optimistic about humanity reaching year-4,000, I'm just possibilistic about it (as in the philosophical meaning [1]). [1] https://en.wikipedia.org/wiki/Actualism#:~:text=possibilism,...

This is more or less the plot of a story by Brazilian science fiction writer Roberto Luiz Calife.

Re: Earth-like planet spotted orbiting Sun’s closest star

#50

Post by grishka »

rbanffy wrote: post #44
tokai wrote: post #23

Earlier quoted context omitted.

I thought the nuclear propulsion options were viable and relative simple.

Even if you get a very high specific impulse, you still need to pack a lot of reaction mass. You'll also need a lot of supplies (or a biome) because even if you get to 0.1 c, it's still 40 years to get there.

I'm not losing hope that there are ways to travel faster than the speed of light that we haven't yet discovered, like bending the spacetime around the spacecraft, or wormholes, or something else of that kind. If various forms of rapidly ejecting matter out of a nozzle really are the only physically viable option for spaceflight, it would be an extremely disappointing universe.
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