Re: Re. life
"Plants would look very strange indeed at least in visible light."
Not necessarily. Most stars - even most "red" dwarfs - would look pretty white to the human eye if you're on a nearby planet because they're usually hotter than any incandescent bulb. A K0 star would have a surface temperature of 5200K, which produces a color balance similar to noontime solar illumination on Earth.
See the center picture for an example of 5200K illumination - it doesn't make much difference once the light source's temperature is above 3000K (like a tungsten bulb):
http://taylortakesataste.com/wp-content/uploads/2011/03/strobe.jpg
http://ezbackgrounds.com/images/blog/kelvin-color-temperature-chart.jpg
Hopefully any photographers will correct me if I'm egregiously incorrect in applying color temperatures to stellar illumination.
Biting the hand that feeds IT
