Mars is spinning faster than before, according to data NASA InSight collected on the red planet.
Astronomers determined that the planet's spin is increasing by about 4 milliarcseconds per year², or shortening the length of a Martian day by a fraction of a millisecond per year. A Martian day is about 40 minutes longer than a day on Earth.
The increase seems incredibly small, but researchers aren't entirely sure what causes it. However, they suggest that it could be due to the accumulation of ice at the Martian poles, or the growth of land masses after becoming covered with ice. When a planet's mass shifts in this way, it can cause the planet's rotation to speed up.
