While many red stars have planets closer than us to our sun it is ok because of the lower radiation of a red star.
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Red dwarfs emit frequent flares that would sterilize a planet.
Red dwarfs emit frequent flares that would sterilize a planet.
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Certainly no more than our own star. The flares of a red star would be nothing compared to our sun. The energy level on a red star surface are minuscule in energy content compared to a yellow star.
A red star is not dangerous because of flares. Red stars are at then end of their life cycle and their likely time until death can be counted in millions of years instead of billions. Red stars are burning helium, usually after starting a collapse that ignited the helium. The extra sudden ignition of helium is what causes the expansion in size. A red star total energy output would be higher than it was before it went red but the energy per square meter would be much less but now the red star has become huge compared to what it was.
If our sun were to start burning helium it’s diameter would likely encompass the orbits of Mercury and Venus and strip away our atmosphere. Mars might like that a lot.
After some millions of years however the helium would be exhausted and heavier atoms would start to be fused into more and more heavy elements until the fusion furnace could no longer support itself. The pressures that hold up the atmosphere would fail and the star would start falling in on itself. The star may convulse by starting to fall with the pressure of the falling star igniting heavier elements enough to sustain the pressure of the atmosphere again for a short time. This could happen several times or only once when vast amounts of matter are combined by fusion into heavy elements in a split second when the pressure of all this sudden fusion explodes the star and the star becomes either a white dwarf or if it was big enough a neutron star.
Any intelligent life near a red star would be looking for a new home well before any of that happened. the good news is that the star would be old and planets that had developed intelligent life would have had perhaps billions of years to develop the technology to either move the planet or move to another planet.
Don’t misunderstand what I say next. Any civilization that far advanced would be incomprehensible to us. To us they would be gods and have a level of intelligence and knowledge that we simply cannot even imagine. To them we would be no more than ants scurrying around building our little cities.