As they move, they observe Earth's weather, oceans, atmosphere and more. The data they beam back to Earth is used to predict weather, understand climate change and track environmental changes.
Inside a giant aluminum shell on the grounds of the library near Pasadena, California, the movements of the spacecraft create an otherworldly soundscape. NASA's Orbit Pavilion, open through September 2019, turns research activities into sound. Go inside the nautilus-shaped sculpture and you'll hear sounds assigned to different Earth science satellites and the International Space Station as each of them crosses over.
Each NASA instrument has been given a sound that represents its mission, such as crashing waves and desert winds. As the satellite moves overhead, its trajectory is reflected through 28 surround-sound speakers.
The experience recruits listeners' ears and minds, reminding them spacecraft are always tracking Earth. Nineteen satellites and the ISS - which makes 16 rotations around Earth each day - are part of the mix.
The shell itself, designed by Jason Klimoski and Lesley Chang, offers glimpses of the sky through its aluminum panels. Those views are a reminder that someone's always watching and that there's plenty of wonder to record.
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