Something about the humidity and water-filled flatness of the Amazon helps transform the sky into a thick pastel painting, full of colors and milky hues. Below are photos of Amazon sunsets over the cities of Manaus and Rio Branco, on the Amazon River, on the Rio Tapajós near the village of Alter do Chão, and from outside the Amazon on the coastal town of Jericoacoara. None of these photos have been doctored or enhanced.