Modals of possibility : Science-fiction et anomalies

You are writing a science-fiction short story set in a parallel dimension. Complete the sentences using modals of possibility (might, may, could) to describe the following scientific anomalies:

1. The gravitational constant is significantly lower than on Earth, where $g = 9.81 m/s^2$. Write a sentence stating that people could leap over obstacles easily.
2. The chemical composition of the atmosphere involves a rare gas, $Z_2$. Suggest that this gas might cause the sky to appear purple.
3. The speed of light in this dimension is denoted as $c' = 2.0 imes 10^8 m/s$. Explain that travel between planets could take longer than expected.