Imagine that, in a thousand years, the star system of Proxima centauri has a planet located in its goldilocks zone that has been terraformed by earthling settlers.

We do not really know what the biosphere of such a planet will be like, so let's assume that it is equal in size, sea/continent ratio, atmosphere, and animal and plant species to the Earth in the 20th century, including the most exotic microorganisms. The only difference would be that it wouldn't have plate tectonics.

Let us suppose that one million human beings live on this planet, in a society that has voluntarily renounced high technology and lives like its ancestors of the year 2020 in a simple, common existence, with satellites and computers, but no nanotech nor AIs. Let's supose they dominate nuclear fusion power.

Would the human species survive? Would any life in Proxima survive?

  • $\begingroup$ Are you referring to Proxima B? $\endgroup$ Apr 16, 2018 at 17:56
  • $\begingroup$ I'd be very surprised if scientists on your Earth didn't point out the folly of choosing a planet near such a star to invest the resources into terraforming. Correct solution : find another rock that's in a better "neighborhood". $\endgroup$ Apr 16, 2018 at 20:21
  • $\begingroup$ They'd never get the chance to renounce high technology because they'd be relying on it every few months, if not every few weeks, in order to survive (if they could somehow provide shielding to the planet). It would be like someone in Canada announcing that they are going to implement a plan to give up on the technology of snow tires and home insulation. Nature's going to intervene on a regular basis to demonstrate the stupidity of that idea. $\endgroup$ Apr 17, 2018 at 3:32

3 Answers 3


Do you have a solar shield?

Artist representation

I agree with @RonJohn's answer, here's my take on it.

Red dwarves have epic awful for life solar flares. These flares can instantly make the star twice as bright and smaller ones are nearly constant, causing the solar flares to literally blow the atmosphere away.

Solution? But you know what? If you've built a transparent Faraday cage around the planet, made out of some handwavium that you have recently acquired, you can sidestep that, and the powerful near constant magnetic fields (oh, I forgot to mention that). And, it has to have a transition-lense type stuff on the inside, so that it can deal with massive fluctuations in solar energy. Your civilization can just neatly ignore the "future tech" stuff and go back to living in peace, oblivious of the shield.


We already have possibly discovered a relatively Earth-like planet in the habitable zone.


The exoplanet is orbiting within the habitable zone of Proxima Centauri, the region where, with the correct planetary conditions and atmospheric properties, liquid water may exist on the surface of the planet.

The problem is that it's really close to the star, and gets regular bathed in a lot of solar radiation.

Also from the Wikipedia article:

The habitability of Proxima Centauri b has not been established,[12][13] since the planet is subject to stellar wind pressures of more than 2,000 times those experienced by Earth from the solar wind.[12][25] This radiation and the stellar winds would likely blow any atmosphere away, leaving the undersurface as the only potentially habitable location on that planet.[26]

And http://iopscience.iop.org/article/10.3847/2041-8213/aaad6b/meta

These analyses reveal that the star underwent a significant flaring event during one of the ACA observations on 2017 March 24. The complete event lasted for approximately 1 minute and reached a peak flux density of 100 ± 4 mJy, nearly a factor of 1000 times brighter than the star's quiescent emission.

So... no terraforming Proxima Centauri b.

  • 2
    $\begingroup$ As much as I agree with your reasoning and I don't think we could terraform or colonize Proxima Centauri b, the question asks what the effects would be if we HAD terraformed it somehow; not whether we can terraform it. $\endgroup$
    – hhoburg
    Apr 16, 2018 at 18:16
  • $\begingroup$ @hhoburg knowing what we know about PCb, if we had the technology to terraform it, this question would be moot since intense shielding would be a big, fat prerequisite of terraforming it. $\endgroup$
    – RonJohn
    Apr 16, 2018 at 18:38
  • $\begingroup$ I agree that we would need atmospheric shielding, but according to the prompt, humans on this planet have renounced 'high technology'; maybe the shield begins to fall into disarray, or maybe the shield wasn't built up for the rare solar flares that occur every hundred years or so? $\endgroup$
    – hhoburg
    Apr 16, 2018 at 18:43
  • $\begingroup$ Then the part of my answer which reads "This radiation and the stellar winds would likely blow any atmosphere away, leaving the undersurface as the only potentially habitable location on that planet" comes into play. $\endgroup$
    – RonJohn
    Apr 16, 2018 at 18:50
  • $\begingroup$ @hhoburg also the solar megaflares occur maybe every few weeks or so... "oh, and bring sunglasses because the sun may randomly decide to become at least twice as bright as it used to be" $\endgroup$ Apr 16, 2018 at 19:56

According to NASA, solar flares and Coronal Mass Ejections (CMEs) can have serious electromagnetic effects on signal transmission. They use GPS satellites as an example, saying that these flares can cause the satellites to be off by 'many meters'; I would assume that, by extension, other signal-based satellites would be unreliable, including telecommunication satellites, defense satellites, and anything to do with space travel.

Furthermore, NASA mentions that CMEs can produce bursts of particles and electromagnetic fluctuations strong enough to blow out transformers at ground level on Earth. That means pretty much any non-protected electrical system could be vulnerable... Including, given enough of these CMEs, protected systems like that of a nuclear reactor, I would imagine.

A lot of this answer depends on distance from Proxima Centauri. As mentioned in another comment, if it is Proxima Centauri b, an exoplanet in Proxima Centauri's habitable zone, it is closer to their sun than we are to our own Sun. In fact, the Wikipedia article for Proxima Centauri b puts the semi-major axis (the furthest point of the orbit) at 0.0485 AU (astronomical units). 1 AU is the distance from the Earth to our Sun, so they would only have about 4% of the distance to their (smaller) star.

The shorter distance means these effects would be greatly magnified compared to a similar CME in our Solar System, and the planet could even experience notable temperature fluctuations (something that is mentioned in NASA's article as not being a threat to Earth because of our distance from the Sun).

Some other effects of these solar flares would be increased aurora frequency/visibility, which could make for an interesting scene on Proxima Centauri b. Also, people like astronauts and airline pilots have increased rates of cancer because they are higher in the atmosphere, which means there is less of a shield for harmful particles. Thus, your planet's inhabitants would be at much greater risk of cancer. For our sun, there are increases in solar flares every 11 years (these are known as a solar maximum). If Proxima Centauri followed a similar pattern, it would result in dramatically increased cancer rates roughly every decade, and by extension there would be many more cancer-related deaths over the year or two after that, which could give some interesting implications on your inhabitant's life expectancies.

I hope this answer helps!


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