As millions of people across North, Central and South America tilt their heads skyward to watch a partial ‘ring of fire’ solar eclipse tomorrow (October 14), NASA engineers will be celebrating the once-in-a-decade event in their own way. : Launching a rocket directly into the shadow of the eclipse.

Do not worry; The sun, the moon and everyone watching will be okay. Three science rockets planned from White Sands Missile Range in New Mexico are part of a purely scientific mission to investigate changes in Earth’s upper atmosphere during the sudden drop in daylight caused by eclipses, according to NASA.

At the peak of Saturday’s eclipse, about 90% of sunlight will be blocked by the moon. We know from previous eclipses that this sudden decrease in daylight can have very strange effects on the planet, including rapid changes in temperature, wind, and even animal behavior. What’s less clear is how the eclipse affects the electrically charged upper atmosphere, or ionosphere, which begins 30 to 50 miles (50 to 80 kilometers) above Earth.

Here, the sun’s ultraviolet radiation knocks electrons out of atoms, creating a vast sea of ​​charged particles throughout the day; As the sun sets, many of these electrons recombine into neutral atoms until the sun’s rays return in the morning and separate them again. During the 2017 total solar eclipse over North America, scientists observed a time-lapse version of this process; The moon completely blocked sunlight for several minutes, causing “ripples” in the ionosphere as the temperature and ion density dropped rapidly, rising again immediately afterwards. peak eclipse.

The combined aerial and ground data will provide APEP researchers with an unprecedented view of atmospheric changes during the eclipse. The team will also recover and reuse eclipse study rockets scheduled to pass North America on April 8, 2024; This time, it will be launched from NASA’s Wallops Flight Center in Virginia, not far from the path of the eclipse.

After that, the team won’t have a chance to launch rockets into the moon’s shadow until 2044, when the next total solar eclipse occurs.