Low gravity causes the heart to weaken, a study has found, after bioengineered heart tissue was sent to the International Space Station (ISS).

Scientists at Johns Hopkins Medicine in Baltimore, US, wanted to find out what low gravity conditions in space do to the human heart.

They placed 48 human bioengineered heart tissue samples on miniature chips, which would collect data about how the tissues beat. The samples were placed in a specifically designed chamber that simulated the environment of a human heart.

The chamber was sent to the ISS onboard the SpaceX CRS-20 mission, which launched in March 2020. Upon reaching the ISS, the tissue samples spent 30 days under observation.

Scientists received real-time data for 10 seconds every 30 minutes about the tissues’ strength of contraction and on any irregular beating patterns.

Bioengineered heart tissue samples from the same source and housed in the same type of chamber were simultaneously observed in the research laboratory on Earth.

When...