"[A]fter the detection of huge solar flares...." Indeed, they'd have to be astonishingly power to reach from the Sun to a planet of Proxima Cen. "Stellar flares," maybe?
Seekers of new worlds for humans to colonise will have to look further afield than Proxima Centauri after the detection of huge solar flares showed its planets are probably uninhabitable. Proxima Centauri became a candidate for exploration, colonisation and/or alien investigation in 2016, when its second planet - Proxima …
I wonder what the former hypothetical habitants might have thought. "Ok, that flare was bad and fried our advanced tech. But the probability of this happening again in our lifetime and for generations to come is very low - it's maximum one in a million."
At least, I guess, they won't have died in a "beast from the east" cold wave.
By sheer coincidence, I am just about halfway through "Proxima", by Stephen Baxter. I thought it took a little while to get going, but I am reasonably hooked now, and I will finish it. Published in 2013, it does indeed have the star flaring quite frequently, but not as badly as we know now.
No spoilers, please!
Please say you were being sarcastic when you referred to New Scientist as "august"!
In today's dumbed-down new media era of anti-science and mistrust of experts and scientists, it seems to me that New Scientist and Scientific American (amongst others) have dumbed down so far that they are fast approaching red top status - from the wrong side.
In today's dumbed-down new media era of anti-science and mistrust of experts and scientists, it seems to me that New Scientist has dumbed down so far that they are fast approaching red top status - from the wrong side.
Can't talk about the others (don't read 'em and I gave up on Scientific American decades ago when its gobbledegook quotient hit 100%), but New Scientist has definitely taken a turn for the better since it exited from the Reed Group. Prior to that I was planning to cancel my subscription, but those plans are now on hold pending an ongoing review.
It's very near, 4 ly versus the approximately 100,000 ly of the diameter of our Galaxy, the Milky Way.
Estimates of the number of galaxies in the observable universe range from 200,000,000,000 to 2000,000,000,000. Andromeda isn't the closest, just the nearest galaxy like ours.
Our Oort Cloud is very wide and maybe from 0.03 to 0.08 ly at closest to as far as 0.79 ly to 3.16 ly. It's sparse, so hard to tell accurately.
So Proxima Centauri B is very close indeed. Though the Oort Cloud outer edge might be a 1000x as far away as the Kuiper belt.
100,000 AU = 1.58 ly. The Kuiper belt is about 30 AU to 50 AU. It's also not got a definite edge.
Voyager 1 is still within the Kuiper belt (40 AU), hardly out the front door!
1 AU = approximate distance Sun to Earth.
Jupiter SEEMS far at about 5 AU and much beyond it solar power isn't much use. Hence EM or Cannae drive or Solar sails only serve to get a fixed velocity long before the Kuiper belt. Very very slow for interstellar travel.
All true, except it is really really near. It's just our probes are much more use for the Solar System. The two Voyagers and Horizon just happen to be exiting the Solar System eventually, but they, as are all of our probes, are Solar System probes. KBOs and Oort Cloud origin comets are really Solar System things. Though we did have a rock from interstellar space visit lately.
A world our distance from GC in our galaxy on the other side is about 40,000 ly away, that's TEN THOUSAND times further than Proxima Centauri.
"and so far the furthest Earth has been able to send an operation space craft is 40 AU and that has taken decades"
The trajectories of the probes in question were never meant for interstellar travel to begin with... They were meant to get the probes to their designated targets as accurately as could be managed. Solar escape velocity was a secondary issue, really. Depends on how you look at it.
Mind... I'd love and applaud any idea that would endeavor seanding a probe away at any appreciable fraction of c.... Doesn't even have to be aimed at anything in particular. The Science that can be done on board while it's speeding up would alone be well worth it.
True, sort of. Planets tend to orbit around the same plane as equator of the rotating star. Simplistically if the flare lasts half the time of the star rotation period (or orbital period of the planet), then 50% chance of toasting a near enough planet. The flares are mostly going to be in the same plane as the planets due to the star's rotation.
Proxima Centauri is a red dwarf, which are known to be more prone to flares. It's much less than the mass of our sun, so flares are worse. It's thought that red dwarfs are poor candidates for ET life as the goldilocks zone is much closer to the star and thus more easily damaged by the usually bigger and more frequent flares.
Proxima Centauri b is really close to the star so a "year" (an orbit) is less than 12 days. Curiously star's rotation period is about 84 days.
There's been a number of breathless stories about potentially habitable exoplanets and just as many deflated follow-ups about how they're probably not habitable after all.
But ultimately, all of this is based on fairly limited data. We haven't actually seen any exoplanets; we haven't measured their atmospheres; and our data set for what actually does constitute a habitable planet is limited to just one single example. We've made inferences and deductions, and I'm fairly happy that the science is good, but it is most certainly very much incomplete.
What we really need is to get some more and bigger instruments up and running to help us find these planets, but also more importantly to *look* at them in detail after we've found them.
I'm excited about TESS, which will be launching soon (even better, it'll be on a Falcon 9), but that will just be another "finding" mission, not so much of the "looking". I'm also looking forward to JWST, which sounds like it'll be even more capable, but that keeps getting delayed.
Frankly, if we're still having debates about how much water is on the Moon (per the other Reg headline today), which is a body that we've actually been to, then I'm doubtful about how accurate we can really expect to be with what all these exoplanets look like.
"Proxima Centauri became a candidate for exploration, colonisation and/or alien investigation in 2016, when its second planet - Proxima Centauri b - was spotted..."
Proxima b is the first (and so far only) planet discovered to be orbiting Proxima Centauri. The designation 'b' is always given to the first planet discovered in a system. The parent star is considered 'a'.
Apologies for the pedantry.
Meanwhile on Proxima B:
Leading scientists have discovered a nearby solar system with a large yellow sun. The third planet in that system is tantalizingly close to supporting life. Unfortunately that planet has a mysterious magnetic field. Scientists speculate that the field would have trapped massive amounts of toxic oxygen on the planet (keep in mind, oxygen is commonly used to clean a plumbus, they have a whole planet full of it!). In addition, the yellow sun must flood the planet with high-intensity ultraviolet and infrared radiation, which surely killed off all life as we know it.
I sure hope there's a lot more decimal places between the most powerful solar flare observed from our sun and one that would kill all life. A flare 1/10th the power of one that increased the brightness of a star by 1000x means our most powerful flare would have made our sun 100x brighter than normal!
Seems more likely Proxima's flare would be 10^10 times more powerful than the most powerful one observed here.
Sounds bad. Expect mutants.
On the other hand, its not clear if life can evolve under truly mind-boggling radiation fields.
Deinococcus radiodurans comes to mind and if there is complex life, maybe 3-5m down in the oceans it might be relatively quiet with very complex life evolving over time and able to predict the flares by "going deep" until it clears.
I did read somewhere that certain organisms replace bases in their RNA, if the have also evolved the ability to use heavy metals as shielding then their cell membranes might be metallic.
Perhaps based on bismuth indium alloy or something similar and in fact they may even be shape-shifters.
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