NASA astronaut Jessica Watkins took the earbud with her to the International Space Station, where she will test the device, according to a CNN report.
Measuring about 1.2 inches long, the earbud is covered in clear silicone and features sensors for tracking heart rate, body temperature, and blood oxygen saturation levels.
The device was developed by a team at the University of California, Berkeley, with a $2.3 million grant from NASA's Advanced Exploration Systems program.
It has been designed to work in the microgravity environment of space and is small enough to be worn comfortably in the astronaut's ear while they sleep.
The earbud sends the data it collects to a small device that fits into a pocket or clips onto a belt, which transmits the information to mission control.
For missions to Mars, astronauts could be in transit for up to nine months. The earbud data will help mission controllers monitor the health and well-being of astronauts on these very long missions.
Astronaut Jessica Watkins will test the device and provide feedback to engineers back on Earth. If the technology passes the test, it could be used by future astronauts traveling much farther into space.
