image: Smoke from fires burning in Siberia have generated a lot of smoke that has blown across the Pacific Ocean and is causing reddish sunsets in the US Pacific Northwest. Smoke from those fires was spotted along the coast of Oregon and over the western part of the state.
The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Aqua satellite captured an image of smoke on April 19 at 21:05 UTC (2:05 p.m. PDT/5:05 p.m. EDT).
The smoke particles from the fires allow sunlight's longer wavelength colors like red and orange to get through while blocking the shorter wavelengths of yellow, blue and green. Those longer wavelengths give the sky a red or orange tinted appearance. Similarly, during sunrise and sunset times when the sun is near the horizon, sunlight has to travel through more of Earth's atmosphere to get to you. The additional atmosphere filters out the shorter wavelengths and allows the longer wavelengths to get through, providing reds and oranges during those times.
Credit: Image: NASA Jeff Schmaltz, MODIS Rapid Response Team. <BR>Text: NASA Goddard Space Flight Center, Rob Gutro