So assuming that you know the size of the sun looking out the window, then it'll look bigger on Venus, huge on Mercury and by the time its out to Neptune it's but a bright star.
The New Horizons page reports:
The latest spectra from New Horizons Ralph instrument reveal an abundance of methane ice, but with striking differences from place to place across the frozen surface of Pluto. "We just learned that in the north polar cap, methane ice is diluted in a thick, transparent slab of nitrogen ice resulting in strong absorption of infrared light, said New Horizons co-investigator Will Grundy, Lowell Observatory, Flagstaff, Arizona. In one of the visually dark equatorial patches, the methane ice has shallower infrared absorptions indicative of a very different texture. "The spectrum appears as if the ice is less diluted in nitrogen," Grundy speculated or that it has a different texture in that area."
As Nitrogen melts at about -210°C it means that the surface there will be bloody cold.
So the sun which heats our world nicely (thank you very much) is shedding so little heat out there that as its size suggests, its not giving much more radiation than a star. Who knows, maybe Jupiter gives is something too...