Is Venus's Rotation Slowing Down?

New data points to a slowing in Venus's rotation since nasa first started taking measurments.

www.astronomy.com...

The European Space Agency’s (ESA) Venus Express spacecraft has discovered that our cloud-covered neighbor spins a little slower than previously measured. Peering through the dense atmosphere in the infrared, the orbiter found surface features were not quite where they should be.

i]reply to post by usmc0311


Curious stuff - Great find! S&F

That is a remarkable rate of change - 6.5 minutes over 16 years. These two possible factors mentioned in the article sound the most feasible to me...

If Venus has a solid core, its mass must be more concentrated towards the center. In this case, the planet’s rotation would react less to external forces.

The most important of those forces is due to the dense atmosphere — more than 90 times the pressure of Earth’s, and high-speed weather systems, which are believed to change the planet’s rotation rate through friction with the surface.

Granted the measurements differ....is this an improvement in instrumentation or sensitivity of telemetric electronics or radars?
If the rotation is perceptibly slower....
I asume that you have the differences and times , the plot could be worked out for the duration tillrotation stops roughly anywas....
Id be interested in you extrapolations as to when this may occur, and what possible consequences may result over time from this???earthquakes?slippage of the crustal outer skin of venus?
The core is also spinning inside too so things may get hairy for the venusians....in a few billion years or so......

so is that a good thing or a universe ending paradox thing?

Originally posted by LonelyGuy
so is that a good thing or a universe ending paradox thing?

Well it might be of interest to note that the ancient Egyptians and Mayans had a real "thing" for Venus. Venus, of course, is also known as the "Morning Star."

Lucifer, the name, is equated to Morning Star.

Jesus of Galilee is said to have stated--in what many think referred to the future:

And he said unto them, I beheld Satan as lightning fall from heaven. (Luke 10:18)

So, End of the World? Maybe. Venus stops spinning and falls like lightning from the heavens?

Originally posted by The GUT
[Well it might be of interest to note that the ancient Egyptians and Mayans had a real "thing" for Venus. Venus, of course, is also known as the "Morning Star."

Lucifer, the name, is equated to Morning Star.

Jesus of Galilee is said to have stated--in what many think referred to the future:

And he said unto them, I beheld Satan as lightning fall from heaven. (Luke 10:18)

So, End of the World? Maybe. Venus stops spinning and falls like lightning from the heavens?

I prefer to think of Venus as the god of love, but then I'm an optimist! Seriously though, even if Venus or any other planet were to stop rotating, the planet would still remain in orbit around the Sun.

Yeah, I wondered about that, but isn't rotation related to stabilization? I think of a gyro, football, or basketball and it made me wonder.

Is Venus about love or lust in the sense you're talking? Depending on your answer: I've been in love dozens of times.

I don't think Copper will be very happy about this . . .

Cu later

Originally posted by The GUT
Yeah, I wondered about that, but isn't rotation related to stabilization? I think of a gyro, football, or basketball and it made me wonder.

Is Venus about love or lust in the sense you're talking? Depending on your answer: I've been in love dozens of times.

Love? Lust? Isn't it just a chemical reaction? (I'm a cynical optimist). I've been in both on more than one occasion too!

Back on topic, If Venus stopped rotating, it would have no effect on its orbit, a Venusian year would still be a Venusian year, but due to the lack of rotation one side of Venus would face the Sun for half of the year and the other side would face the Sun for the other half of the year, giving the planet a 'day' that would last half of its year. This would result in very different weather conditions on the planet indeed! Rotation has no effect on the stability of a planets orbit though.

Edit to add: Thinking on it, Venus in all likelihood wouldn't stop spinning completely as anything in orbit will eventually become tidally locked with the larger body and rotate at the same rate as its orbit - just as the moon does as it orbits the Earth. That would of course give one half of Venus perpetual day. - Sorry for my fragmented thinking.. I'm working nights at the moment!

Originally posted by stirling
I asume that you have the differences and times , the plot could be worked out for the duration tillrotation stops roughly anywas....

Actually the data taken as a whole and at face value simply indicate a non-constant rotation rate for Venus. Multiple earth-based radar studies measured the rotation rate of Venus prior to Magellan and arrived at numbers between 243.022~243.025 plus or minus 0.002~0.006. They used a couple of techniques to try to measure the rotation rate using Magellan, but the one they ultimately went with involved improving the spacecraft ephemeris to attain the accuracy needed to measure the rotation. This resulted in an order of magnitude improvement in the uncertainty level of the measurements as compared to other techniques and produced the current accepted number of 243.0185 plus or minus 0.0001.

Interestingly though, when they tried to establish a longer baseline of measurement using older data from the Venera 15/16 probes, the resulting rotational period solution was 243.023 plus or minus 0.001 days, matching the current value measured by the Venus Express probe. This joint Venera-Magellan solution was disregarded though as being subject to ephemeris errors in the Venera probes that could not be corrected the way they were for Magellan, as well as the fact that Venera did not have as much radar resolution as Magellan. In light of the current evidence it seems it may have not been an incorrect solution, in fact it matches Venus Express' solution.

At best the new Venus Express data means that Venus' rotation is variable due to atmospheric and possibly geological forces at work under the surface as well, but taken as a whole the data do not indicate a steady slowing, rather they indicate an inconstant rate of rotation.


M. E. DAVIES,T. R. COLVIN,P. G. ROGERS, P. W. CHODAS, W. L. SJOGREN, E. L. AKIM, V. A. STEPANYANTZ, Z. P. VLASOVA, A. I. ZAKHAROV. 1992. The Rotation Period, Direction of the North Pole, and Geodetic Control Network of Venus. Journal of Geophysical Research. Vol 97, No. E8, Pg 13, 141-13, 151.