When in space the sun appears white to astronauts but the sun is actually a mix of all colors and it's also an illusion that makes the sun appear white in space and white during noon or yellow during the day.
The sun appears to be white in color at noon time because the sun is overhead and there is least amount of scattering and hence the sun appears white.
When it is overhead, it has lesser air to travel through and scattering results from dust and other particles which will be reduced if the distance to be traveled in air is reduced.
The actual color of the sun is a mixture of yellow, orange and red and all other colors mixed together.
The most common colors of the sun are the red, orange and yellow and is why the sun appears yellow from the earth.
But in reality the actual color of the sun is all colors mixed together.
Although the sun appears yellow from earth the sun is not actually yellow but instead it's just an illusion caused by the Earth's atmosphere.
The powerful processes happening inside the Sun are so robust that it emits every color of light imaginable. Together, these colors form a pure white light, which is precisely what you'd see from space.
But in outer space the sun appears to be a white in color but it's all different colors.