The Planet Venus is Slowing Down, but Only Sometimes

Recent studies have provided new insights into Venus’s rotation, revealing a complex picture of its rotational dynamics:

Current Rotation Period

Venus’s rotation period is now measured to be 243.0212 ± 0.00006 Earth days, slightly longer than previously thought[5].

Variability in Rotation

1. Venus’s rotation rate is not constant but fluctuates over time[5].
2. The length of a Venusian day can vary by up to 20 minutes[5][6].

Is Venus Slowing Down?

The question of whether Venus is consistently slowing down is not straightforward:

1. Short-term observations: Venus Express data in 2012 suggested Venus was rotating about 6.5 minutes slower compared to measurements from the 1990s by NASA’s Magellan probe[1].

2. Long-term trends: More recent studies using 29 years of radar observations (1988-2017) have not detected a resolvable trend in Venus’s rotation rate[6].

3. Atmospheric influence: Venus’s dense atmosphere is believed to be the primary factor affecting its rotation[3][5].
– The atmosphere can both slow down and speed up the planet’s rotation.
– It exchanges angular momentum with the solid planet, causing variations in the rotation rate[5].

4. Tidal effects: While tidal forces from the Sun tend to slow Venus’s rotation, the planet’s atmosphere counteracts this effect to some degree[3].

Conclusion

While short-term observations have shown variations in Venus’s rotation rate, including periods of apparent slowing, long-term studies have not conclusively demonstrated a consistent slowing trend. The planet’s rotation appears to be in a state of complex fluctuation rather than steady deceleration[5][6].

Read More
^{[1] https://www.science.org/content/article/scienceshot-venus-slowing-down
[2] https://en.wikipedia.org/wiki/Venus
[3] https://www.space.com/venus-atomphere-slows-down-rotation
[4] https://pmc.ncbi.nlm.nih.gov/articles/PMC5385710/
[5] https://www.college.ucla.edu/2021/04/29/how-long-is-a-day-on-venus-scientists-crack-mysteries-of-our-closest-neighbor/
[6] https://www.frontiersin.org/journals/astronomy-and-space-sciences/articles/10.3389/fspas.2023.1188096/full
[7] https://phys.org/news/2019-05-possibility-life-venus.html
[8] https://newsroom.usra.edu/from-earth-like-to-extreme-new-study-explores-venuss-atmospheric-evolution/}