As night falls, El Morro National Monument is enveloped in a deep natural darkness far from the city lights. The high elevation, clean air, remote location, and minimal development in and around the El Morro Valley combine to produce optimal night-sky conditions. Experience the sky filled with light from thousands of stars as the Milky Way stretches from horizon to horizon!
Night Sky Monitoring
To track changes in night sky darkness, special cameras are used by park scientists to precisely measure light pollution coming from urban areas. For example, this black-and-white image taken from El Malpais National Monument, just east of El Morro, shows the dull glow of Grants and Albuquerque on the horizon.
When the image is analyzed by a computer, an exact level of brightness can be calculated and is shown below in a rainbow of colors. This allows the light levels from one photograph to be easily compared to a photograph taken at another location or another year.
Here you can clearly see the light pollution, in white-to-red-to-yelllow, from the two cities.
You Can Help!
Next time you turn on your lights at home, visit a store to shop after dark, or come to a remote place like El Morro and look at the night sky, think about how much light is escaping into the night sky and blocking out the stars. There are many things you can do to reduce light pollution, and a great place to start is: https://www.nps.gov/subjects/nightskies/practices.htm
Last updated: February 21, 2021