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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

#21

Post by Udo »

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. Or 9 years if we 'only' get to 0.5c.

The same goes for laser-driven light sails if we just wanted to send a probe, although deceleration would be an issue. (There is currently an aspirational research project for this called Breakthrough Starshot)

The exciting thing about these technologies is that they don't require new physics in principle, just a lot of engineering. Of course, uploaded minds would probably always be better suited for space travel, but it's neat to know that even biological people could in theory make these trips.

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

#22

Post by _fizz_buzz_ »

chadcmulligan wrote: post #18
ilija139 wrote: post #14

Just for reference, the planet is 4.0×10^13 kilometres away, if we send our fastest ever probe, and assume it averages the top speed of 586,800 km/h all the way there, it will still take 7,781 years to reach the planet.

Under 1g acceleration about 3.5 years https://www.omnicalculator.com/physics/space-travel

1) you also need time decelerate

2) speed of light is a hard limit, you cannot keep accelerating and you need more energy the closer you get to that limit

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

#23

Post by tokai »

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.

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

#25

Post by brabel »

WithinReason wrote: post #20
lbriner wrote: post #17

We can't even work out how to run our own planet in a consistent and consensual way, I say leave it to the other more civil aliens to inhabit, otherwise we'll end up with another broken planet.

What is there to break on a lifeless planet?

Whether there's life on this planet is not known, it's in the inhabitable zone so that possibility cannot be discarded.

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

#26

Post by tokai »

_fizz_buzz_ wrote: post #22
chadcmulligan wrote: post #18

Earlier quoted context omitted.

Under 1g acceleration about 3.5 years https://www.omnicalculator.com/physics/space-travel

1) you also need time decelerate 2) speed of light is a hard limit, you cannot keep accelerating and you need more energy the closer you get to that limit

> 1) you also need time decelerate

No that would be a waste of effort. A flyby mission definitely makes the most sense. The 3.5 years are with deceleration though.

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

#27

Post by rob74 »

denton-scratch wrote: post #16

"Earth-like planet"? It orbits the star every 5 days; it's a quarter of the earth's mass. It's also a tenth the distance from its star that Mercury is from the Sun. It's earth-like only in that its temperature is consistent with there being liquid water.

Well, Proxima Centauri isn't really "Sun-like" either, so what constitutes an "Earth-like" planet for a different type of star is debatable...

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

#28

Post by b112 »

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…

Easier to add water to Mars, or fix Venus, all possible to have well underway by end of century.

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

#29

Post by [deleted] »

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…

[deleted]

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

#30

Post by michaelerule »

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…

Is the 6 years measured in the time-frame of a passenger on the spacecraft, or as observed from Earth?
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