alt Hacker NewsSure, the sun is white, more or less (cf comments re human perception and what "white" really means).
But when did humans first perceive the sun as white? We can only reliably say "sometime on or after 12 April 1961", the day Gagarin went into space. Prior to that, as far as we know, all humans saw the sun as some other colour, most often yellow or red, depending on the time of day.
Since Newton's prism, we had pretty good reason for believing it was likely white, reasons that got stronger in the 19th C with improved theories of optics, the discovery of atomic spectra, etc. I'm curious to know when we confirmed for sure its whiteness, and whether this was before October 1957 (Sputnik) or after Gagarin or somewhere in between.
The direct light from the Sun is yellowish, because the blue light of the sky is subtracted from it.
If the sky is covered with clouds, then the light is white, because the blue sky light is mixed again with the direct Sun light.
If the sky is clear and there is an unobstructed view of it, the light reflected by a white object will be the sum of the light coming from the sky to the object and directly from the Sun to the object, so it will be white. For example this is true for white clouds and white snow.
This, i.e. that the Sun outside the atmosphere is perfectly white, has been understood for a long time, since the 19th century.