Table 1 Summary of the results of the experiment. Minimal O2 pressures were taken over datasets (3 datasets for He and 3 datasets for N2 were used).

From: A qualitative assessment of limits of active flight in low density atmospheres

Experiment (initial atmosphere in the experimental bottle chamber)

N2

He

First documented restoration of activity (one fly walking at least one body length)

O2 pressure (mbar)

33

33

Density (kg/m3)

1.26

0.35

Climbing on walls

O2 pressure (mbar)

38

48

Density (kg/m3)

1.26

0.43

First documented flight

O2 pressure (mbar)

46

142

Density (kg/m3)

1.26

0.93