Tennis Balls and the Sun

Tennis Balls were originally white but sir David Attenborough, who was the head of the BBC at the time decided they should be yellow so they could be seen clearly on colour (colour) TV screens. White balls were very easy to see on black and white screens but not so clear on colour ones. 

~ image generated by artificial intelligence (chatGPT)

In space the sun is white but the blue portion of the light separates from the ray when it passes through the atmosphere and makes the remaining colours appear yellow. The Blue portion of the sun light eventually becomes scattered and causes the sky to appear blue. 

So the sun and tennis balls both originally appear white. 

Sources

~2024 QI facts by John Lloyd 

~BBC

~ NASA.gov website