NASA and the Korea Astronomy and Space Science Institute are testing a new way to study the Sun. From NASA’s Columbia Scientific Balloon Facility’s field site in Fort Sumner, New Mexico a football field-sized balloon is flying to the edge of Earth’s atmosphere. It’s carrying an instrument called BITSE — the Balloon-borne Investigation of Temperature and Speed of Electrons in the corona — to demonstrate its readiness for future missions. BITSE is a coronagraph that blocks the Sun’s bright disk to reveal and measure the Sun’s tenuous atmosphere, the corona. While standard coronagraphs measure the corona’s density, BITSE also measures the temperature and speed of electrons in the corona. These three measurements are key for understanding the source of the solar wind, the Sun’s constant stream of charged particles. Understanding how the solar wind is formed can help improve forecasts of solar eruptions, which, if directed at Earth, can affect our GPS signals and satellites in space. Key parts of this instrument were first tested during the 2017 total solar eclipse. On the balloon, BITSE will fly 22 miles above the ground for at least 6 hours, gathering observations and providing test data for 150 times longer than it could during the few minutes of an eclipse. Balloon platforms are a low-cost way to conduct science investigations, train the next generation of scientists and engineers, and test instruments before they head to space. Information from BITSE’s balloon flight will help fine-tune this technology for a future space mission.