I've seen the same planet colored differently in different photos. Here are the true colors of major planets to the best of my knowledge (spacecraft photos appearing in the media often have false coloration): Mercury: grey; Mercury has practically no atmosphere, so we just see the rocky surface.
Sitting for hours can cause poor circulation which is a major cause of the heavy legs syndrome and if there no underlying medical condition and the feeling worsens when walking upstairs, then curiously enough, you might like to look at your diet for clues.
Deep vein thrombosis, or DVT, a blood clot in a deep vein that develops after extended periods of inactivity, can also cause major leg pain. Long flights or car rides make it difficult for the leg to return blood back to the heart. If that blood return slows or stops, it can create a clot within the vein.