by Ann » Fri Aug 26, 2016 4:02 am
Chris Peterson wrote:Ann wrote:Proxima Centauri is a flare star. That means that it can suddenly release a sudden burst of energy that briefly makes it perhaps twice as bright as it normally is. That wouldn't be healthy for any surface-dwelling beings on Proxima Centauri b, but perhaps life could still exist and thrive underground.
That's not obvious. If the Sun occasionally doubled its intensity for a few seconds, I don't imagine it would have any significant impact on surface life. Looking at the entire biosphere, there's more than a twofold difference in solar intensity at any time.
I just grabbed that estimate of Proxima's brightening during flares, "twice as bright", out of thin air so to speak, because a quick googling didn't tell me how much it would brighten during flares.
But Proxima is indeed classified as a flare star, whereas the Sun isn't. And while we are unlikely to miss any upheavals on the Sun, we might well miss flares on Proxima - at least we may have done so in the past, before Proxima was so closely monitored.
Also the Earth is 150 million kilometers away from the Sun, whereas Proxima B is about 7 million kilometers away from Proxima. So not only is Proxima likely to brighten more during flares than the Sun does during flares in relation to each star's normal brightness, but the Earth is also twenty times farther away from its star than Proxima B, and is likely to suffer less from the upheavals of its Sun than the newly discovered planet of Proxima.
Ann
[quote="Chris Peterson"][quote="Ann"]Proxima Centauri is a flare star. That means that it can suddenly release a sudden burst of energy that briefly makes it perhaps twice as bright as it normally is. That wouldn't be healthy for any surface-dwelling beings on Proxima Centauri b, but perhaps life could still exist and thrive underground.[/quote]
That's not obvious. If the Sun occasionally doubled its intensity for a few seconds, I don't imagine it would have any significant impact on surface life. Looking at the entire biosphere, there's more than a twofold difference in solar intensity at any time.[/quote]
I just grabbed that estimate of Proxima's brightening during flares, "twice as bright", out of thin air so to speak, because a quick googling didn't tell me how much it would brighten during flares.
But Proxima is indeed classified as a flare star, whereas the Sun isn't. And while we are unlikely to miss any upheavals on the Sun, we might well miss flares on Proxima - at least we may have done so in the past, before Proxima was so closely monitored.
Also the Earth is 150 million kilometers away from the Sun, whereas Proxima B is about 7 million kilometers away from Proxima. So not only is Proxima likely to brighten more during flares than the Sun does during flares in relation to each star's normal brightness, but the Earth is also twenty times farther away from its star than Proxima B, and is likely to suffer less from the upheavals of its Sun than the newly discovered planet of Proxima.
Ann