Has it been spotted though? Indirect evidence shows something is there. But no one has seen it, not any image has been produced.
Earth-like planet spotted orbiting Sun’s closest star
101–110 of 351 posts
Re: Earth-like planet spotted orbiting Sun’s closest star
#102Earlier 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 literally the plot of a very old computer game Alien Legacy. [0]
Re: Earth-like planet spotted orbiting Sun’s closest star
#103Earlier quoted context omitted.
> a trip to the next star can be a week-long affair from your point of view You’d need to travel at around 233x the speed of light to make getting to the nearest star be a week trip, no?
Nope! If you obtain the full speed of light then a) you're not made of baryons anymore so congratulations on that and b) no time passes whatsoever between your being emitted in some tight laser beam on planet A, and being transcribed on planet B, from your perspective. None. Photons don't experience time, they are time.
Not exactly. For you to think you are traveling 20x faster than light, your friends that stayed at home would have to see you traveling at 0.99995c. For 233x faster than light, that's a lot of 9's in that number.
Re: Earth-like planet spotted orbiting Sun’s closest star
#104Has it been spotted though? Indirect evidence shows something is there. But no one has seen it, not any image has been produced.
'detected' would be more accurate, but this is a pop sci take on a press release that says "New planet detected around star closest to the Sun" [1] of a paper called "A candidate short-period sub-Earth orbiting Proxima Centauri" [2]. That's often how it goes, each new medium picking it up adding more and more embellishment, graphics of green-and-blue planets, and breathless fantasizing about one day colonizing the stars.
"Earth-like planet spotted orbiting Sun's closest star" is a lot sexier than "We detect a signal at 5.12 ± 0.04 days with a semi-amplitude of 39 ± 7 cm s−1. The analysis of subsets of the ESPRESSO data, the activity indicators, and chromatic RVs suggest that this signal is not caused by stellar variability but instead by a planetary companion with a minimum mass of 0.26 ± 0.05 M⊕ (about twice the mass of Mars) orbiting at 0.029 au from the star. The orbital eccentricity is well constrained and compatible with a circular orbit."
Re: Earth-like planet spotted orbiting Sun’s closest star
#105"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.
Could you please stop ruining cool science journalism headlines with your facts?
Re: Earth-like planet spotted orbiting Sun’s closest star
#106Earlier quoted context omitted.
> 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. Indeed. If that's the case, the universe is an infinitely big and infinitely boring place. OTOH, our future uploaded selves may be able to slow down their clock rates and make the trip so much shorter. And you don't need to leave your dear ones on…
What would that fork think of it?
If I were to fork myself in this situation, I'd make one fork who thinks that making the trip will be awesome and another that will think that staying home is the coolest thing.
If we can, from time to time, merge our memories and refork, this wouldn't be a big issue, as both forks would experience both lives.
I think that, at this point, we wouldn't be that much human anymore.
Re: Earth-like planet spotted orbiting Sun’s closest star
#107Earlier quoted context omitted.
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.
> 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. Indeed. If that's the case, the universe is an infinitely big and infinitely boring place. OTOH, our future uploaded selves may be able to slow down their clock rates and make the trip so much shorter. And you don't need to leave your dear ones on…
At the moment I have more faith that our AI overlords - or, future self-replicating robots, insert various levels of intelligence and self-reliance here - will be the ones going interstellar, not so much us unless we revolutionize spaceflight. That said, the picture of the future that The Expanse investigates seems to be the most realistic, just minus the somewhat magic propulsion system.
Re: Earth-like planet spotted orbiting Sun’s closest star
#108Another 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…
Whenever I read discussions about space travel and trying to approach the speed of light for human travel I have the feeling there's a lot of tunnel vision (excuse the pun). It always seems to assume travelling along a linear path through space.
In my mind, using the admittedly poor analogy of space-time as a membrane that is distorted by gravity, my thinking is we'll find some way to effectively bring two points in space-time adjacent to each other and 'step' between them. Wormholes, Warp, or whatever you want to call it.
Think of a flexible membrane 10 meters long and we are going to travel from one end to the other. We can either travel in a linear fashion over its surface for 10 meters or we can wrap the membrane so both ends are next to each other and travel 0.01m across the gap between them.
Yes, I know there are all sorts of obstacles and arguments against this simplistic visualisation but this is how I've always imagined the physics of any science fiction faster-than-light travel - worm-holes, warp drives, etc.
If you want an actual, real, possible-right-now analogy, think of our current situation where the fastest way to travel from London, UK to Sydney, Australia (1/2 way around the world) is through the atmosphere in an aeroplane travelling ~17000 kilometers and taking at best 19.5 hours.
SpaceX (Musk) Virgin Galactic (Branson), other companies [0], and space agencies [1] have talked about, and are actively working toward, stepping outside the atmosphere into space to reduce the time element to around an hour.
So just like with supposedly faster-than-light travel, by 'stepping outside' the linear/conventional thinking/physics we reduce the time of travel element dramatically. The start and end points don't move but the distance travelled by the transport vehicle itself changes in order to enable the reduction in time.
[0] https://www.telegraph.co.uk/travel/news/new-flights-space-lo...
[1] https://edition.cnn.com/travel/article/hypersonic-flight-air...
Re: Earth-like planet spotted orbiting Sun’s closest star
#109Earlier quoted context omitted.
"Earth-like" just means terrestrial, as opposed to jovian. It means it has a rocky surface.
Venus is also classified as Earth like, but it's rocky surface looks more like hell than the mythological descriptions of it. ;-)
Since we're being a bit pedantic in this thread, the biblical descriptions of hell are limited to darkness and gnashing of teeth.
Re: Earth-like planet spotted orbiting Sun’s closest star
#110"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.
"Earth-like" just means terrestrial, as opposed to jovian. It means it has a rocky surface.
Terrestrial and rocky are both far better choices to communicate the concept.