During a short flight over Venus, NASA’s Parker solar probe detected a natural radio signal.
On July 11, 2020, the Parker solar probe flew past Venus for the third time. Each pass is needed in order to use the planet’s gravity to fly the spacecraft closer and closer to the Sun.
One of the instruments of the Parker solar probe is FIELDS: the instrument detected a natural low-frequency radio signal that was not previously attributed to the activity of the planet.
Like Earth, Venus has an electrically charged layer of gas at the top of its atmosphere called the ionosphere. These are charged gases or plasma that emits radio waves: they can be detected by devices such as FIELDS.
When Glyn Collison of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and his team detected this signal, they realized that the Parker solar probe had penetrated Venus’s upper atmosphere.
Understanding why Venus’s ionosphere is thinning near the solar minimum is part of the puzzle of how Venus responds to the Sun. The answers to these questions will help researchers determine how Venus, once so similar to Earth, became lifeless and toxic.