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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

#161

Post by LeifCarrotson »

irrational wrote: post #156
ethbr0 wrote: post #144

Earlier quoted context omitted.

Here's a good collection of details about the entire star system of Proxima Centauri, including its planets. https://www.star-facts.com/proxima-centauri/ Also fascinating, a relative distance vs time graph of close stars. It turns out we'll have closer distances for 6 in the next 10,000 - 50,000 years. https://www.star-facts.com/wp-content/uploads/2020/08/Neares... Somehow I feel like Elon Musk has a print out of tha…

I only counted 5 (including Proxima Centauri). What are the six that you see?

Barnards Star, Lalande 21185, then Alpha Centauri, then Proxima Centauri, then Ross 248, then Gliese 445 makes 6.

There are 6 if you count Proxima Centauri and Alpha Centauri separately; 7 if you count both stars in the Alpha Centauri pair separately, and 5 if you count Alpha and Proxima Centauri separately.

Alpha Centauri is the binary system of Alpha Centauri A and Alpha Centauri B, which are separated by about 10-30 AU. It's very, very close in terms of interstellar distances to Proxima Centauri, which is a red dwarf that orbits Alpha Centauri A and B at a distance of 13000 AU, or 0.2 LY - a remote enough orbit that it makes sense to keep track of whether it's on the near side or far side of the triple-star system.

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

#162

Post by [deleted] »

rbanffy wrote: post #103
samatman wrote: post #100

Earlier quoted context omitted.

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.

[deleted]

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

#163

Post by rbanffy »

Cthulhu_ wrote: post #107
rbanffy wrote: post #53

Earlier 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…

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.

Not a huge problem if, after the robots terraform the planet and build our settlements, I can opt to be printed into a new organic body.

We'll still need some form of magical propulsion or, worse, some magical power source. There aren't many things that can keep providing energy for thousands of years. I'm pretty sure fission is a non-starter here and even nuclear fusion designs would need a source of tritium because, after a couple thousand years, there won't be much left of the initial fuel.

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

#164

Post by netcraft »

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…

The formal name for this is the https://en.wikipedia.org/wiki/Interstellar_travel#Wait_calcu...

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

#165

Post by throw1234651234 »

grishka wrote: post #134
throw1234651234 wrote: post #90

Earlier quoted context omitted.

That's insane optimism to me. We don't even know how to get a nail to re-attach to a nail bed. We can't put some crystals on a tooth. We can't create a single hair follicle. We have zero non-surgical ways to repair arteries. Etc, etc, etc. We have made zero progress in anti-aging other than controlling blood pressure and identifying harmful chemicals in an environment. We ARE good at extreme, surgical and or heavy me…

We're now capable of programming cells to produce arbitrary proteins at will, how cool is that? Also please do look through the playlist in a sibling comment. Michael Levin's research is truly badass. He has grown tadpoles with an extra working eye on the back, and recently he has regrown an amputated leg on a frog. There's an astonishing amount of untapped possibilities in biology that are opening up only now as we…

Right, CRISPR is ok, but they haven't figured out that many real applications. This approach to vaccines has actually been around forever.

I bookmarked this thread specifically to watch your links later. I appreciate them and will watch, as I am really interested in the topic.

My hope is that biotech is the next step, but as I mentioned, for now I am highly pessimistic. We can't seem to treat virtually anything in any real sense, despite the experiments you mention. If anything, the progress in prosthetics (including the spinal bypass) has been great, but nothing to do with life extension or genuine recovery of lost functionality without surgical intervention.

Personally, it seems to be me that the closest thing we can do so far as individuals is reduce risk factors and try to stay high on Death Clocks: https://www.lifespan.io/news/grimage-is-the-best-clock-for-p...

Completely unrelated, but this reminded me that we can't seem to regrow cartilage either. This is a huge issue after cancers and cardiac deaths. Any falls, excessive wear and tear, etc all destroy quality of life with the joints. Latest efforts here: https://www.studyfinds.org/arthritis-pain-regrowing-cartilag...

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

#166

Post by ck2 »

I found this little ditty in a linked article way way way more fascinating:

> Humanity’s first chance to explore this nearby world may come from the recently announced Breakthrough Starshot initiative, which plans to build fleets of tiny laser-propelled interstellar probes in the coming decades. Travelling at 20% of the speed of light, they would take about 20 years to cover the 1.3 parsecs from Earth to Proxima Centauri.

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

#167

Post by spywaregorilla »

ethbr0 wrote: post #149
spaetzleesser wrote: post #64

Earlier quoted context omitted.

Going to Mars seems pretty useless to me at this time. It’s a super hostile environment and we don’t have the technology yet to have a self sustaining base there. Give it a few decades and progress in robotics will make a Mars base much easier. There is plenty of work to be done on Earth. We have to solve clean energy production and in general reduce pollution. These are massive technological challenges that deserve…

Going to {the Middle East, Europe / Asia, Australia, the New World, interior South America, the North American West) seems pretty useless to me at this time. It’s a super hostile environment and we don’t have the technology yet to have a self sustaining base there. Give it a few decades and progress in {insert technology} will make a base much easier. There is plenty of work to be done on {current place}. We have to…

Mars is multiple orders of magnitude more difficult to survive on than the Middle East. Its not really comparable at all.

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

#168

Post by [deleted] »

irrational wrote: post #156
ethbr0 wrote: post #144

Earlier quoted context omitted.

Here's a good collection of details about the entire star system of Proxima Centauri, including its planets. https://www.star-facts.com/proxima-centauri/ Also fascinating, a relative distance vs time graph of close stars. It turns out we'll have closer distances for 6 in the next 10,000 - 50,000 years. https://www.star-facts.com/wp-content/uploads/2020/08/Neares... Somehow I feel like Elon Musk has a print out of tha…

I only counted 5 (including Proxima Centauri). What are the six that you see?

[deleted]

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

#169

Post by [deleted] »

_blu wrote: post #55
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…

we need to send out a probe now before it's too late

[deleted]

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

#170

Post by strogonoff »

enkrs wrote: post #57
b3lvedere wrote: post #5

"The team used a state-of-the art spectrograph called ESPRESSO" And suddenly i am imagining lots of very smart people drinking lots of caffeine. "To find the wobble.." this is not helping :) "ESPRESSO is kept in a special room at the observatory, inside a tank " oh come on ..

Astronomers go to great lengths to name their stuff for good abbreviations. ESPRESSO is actually “Echelle Spectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations”

Astronomers are known to backronymise: https://en.wikipedia.org/wiki/STEVE
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