Understanding the impact of space exploration remains biologically elusive. Cell Press is dedicating this month to space (Afshinnekoo et al., 2020), with the Open-Science NASA GeneLab database and the study showing that mitochondria are key to investigating the biological impact of spaceflight (da Silveira et al., 2020).

Walls et al. find that exposure to microgravity aboard the ISS causes heart dysfunction in a fly cardiac model. Hearts are less contractile and exhibit changes in genes and proteins that maintain heart structure and function. Effects are seen in several lines of flies, suggesting a common response to microgravity.

Consistent with findings first observed for NASA’s One-Year Mission twin astronaut, Luxton et al. report spaceflight-specific telomere elongation in ISS crewmembers on shorter duration missions. Signatures of persistent DNA damage responses in the space radiation environment are also observed, providing potential mechanistic insight into telomere maintenance pathways during spaceflight.

Long-duration space travel is marked by a unique combination of stressors known to impact human aging. Using data from six participants of the Mars-500 mission, a high-fidelity 520-day ground simulation experiment, Nwanaji-Enwerem et al. report significant associations of mission duration with decreased biological aging measured via blood DNA methylation.