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Did Venus Have A Moon?
nprev
post Oct 11 2006, 07:06 PM
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...or two?

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RNeuhaus
post Oct 12 2006, 02:49 PM
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QUOTE (nprev @ Oct 11 2006, 02:06 PM) *

So that it would be probed, Venus must show any impact marks of two moons.

Does the Magallen's radars show any indication of these impacts? I haven't heard of anyone speculating about this. However, I seems that it would be very hard to prove since at about 500 millions years ago Venus might have undergone a big volcan eruption that have resurfaced most of the planet.

Anyway, due to its odd direction of its polar spin, there must have some kind of impact that have changed its polar position and not due to the influence of Sun tidal and the Venusian's massive atmosphere in which they are, most probably, be impossible to alter the polar positions.

On the other hand, I think that the changing the rotation way by reversing the poles is lower than by reversing the rotation direction which would be twice force than the polar's one. So, this kind of mystery would continue...and hope to attract more spacecraft to visit to Venus. smile.gif

Rodolfo
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JRehling
post Oct 12 2006, 04:08 PM
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QUOTE (RNeuhaus @ Oct 12 2006, 07:49 AM) *
So that it would be probed, Venus must show any impact marks of two moons.

Does the Magallen's radars show any indication of these impacts? I haven't heard of anyone speculating about this. However, I seems that it would be very hard to prove since at about 500 millions years ago Venus might have undergone a big volcan eruption that have resurfaced most of the planet.

On the other hand, I think that the changing the rotation way by reversing the poles is lower than by reversing the rotation direction which would be twice force than the polar's one. So, this kind of mystery would continue...and hope to attract more spacecraft to visit to Venus. smile.gif

Rodolfo


Venus does not show any such features, although you correctly note that it might have been covered by volcanism -- we aren't seeing very much of Venus's full history on its surface.

Note, though, just how slow Venus is rotating: 4 miles per hour = 6.5 km/hour. It doesn't take much of an input to that system to make whatever change you would like.

The low inclination is another argument for a solar-tide basis to Venus's rotation.

I suggested a few years ago that Mercury may bear the impact scar of a satellite that "augured in". There is a large radar feature called "Feature C" that is near the equator and 240 West longitude -- an area not imaged by Mariner 10. That area shows nothing especially compelling in albedo maps made with Earth-based telescopy, but neither does the estimable Caloris basin, which simply isn't much of an albedo feature. There is another proposed near-equatorial basin that has perhaps been imaged as a *relief* feature casting shadows of a double-rimmed basin, around 270 West longitude. We will find out more about the anti-Mariner hemisphere of Mercury when Messenger makes its initial flybys and then enters orbit.
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RNeuhaus
post Oct 12 2006, 06:53 PM
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QUOTE (JRehling @ Oct 12 2006, 11:08 AM) *
I suggested a few years ago that Mercury may bear the impact scar of a satellite that "augured in". There is a large radar feature called "Feature C" that is near the equator and 240 West longitude -- an area not imaged by Mariner 10. That area shows nothing especially compelling in albedo maps made with Earth-based telescopy, but neither does the estimable Caloris basin, which simply isn't much of an albedo feature. There is another proposed near-equatorial basin that has perhaps been imaged as a *relief* feature casting shadows of a double-rimmed basin, around 270 West longitude. We will find out more about the anti-Mariner hemisphere of Mercury when Messenger makes its initial flybys and then enters orbit.

The longitudinal 270 degrees West of Mercury are still not shown in maps except from 0 to 180 degrees West. Mariner 10's three fly-by only took half planet picture and hope that Messenger would success its mission and by able to take pictures to all round Mercury planet.

On the other hand, about the two theories which leads to explain to the Venusian's oddy rotation (opposite and slow) are:
  1. Impact by at least two Moons
  2. Solar tidal influence
However, the only true is that there are similiarities of slow axis rotation behavior of Mercury and Venus comparing to the planet orbit around the Sun. The Earth would be an exception to that in fact that it was hit by a Mars' size that leaded in the creation of Moon. The hard hit on Earth might have implicated to accelerate the Earth spin axis rotation. Doesn't it?

However, the slow axis rotation of Mercury and Venus would be the best goal to explain the enigma.

Rodolfo
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Posts in this topic
- nprev   Did Venus Have A Moon?   Oct 11 2006, 07:06 PM
- - Myran   I read it and agree that slow rotation of Venus ar...   Oct 11 2006, 08:01 PM
- - Jyril   I agree, the theory sounds a bit too complicated a...   Oct 11 2006, 08:08 PM
- - Rob Pinnegar   Cute, but it's just speculation. Nobody can pr...   Oct 11 2006, 08:09 PM
|- - JRehling   Keep in mind that the rate of Venus's rotation...   Oct 11 2006, 09:07 PM
|- - AndyG   QUOTE (Rob Pinnegar @ Oct 11 2006, 09:09 ...   Oct 12 2006, 08:41 AM
- - tasp   Whew, heady stuff. I think the odds for the Satur...   Oct 12 2006, 03:20 AM
- - nprev   I gotta agree with the majority opinion so far; th...   Oct 12 2006, 03:53 AM
- - edstrick   Venus's solar tidal drag on the solid body is ...   Oct 12 2006, 10:18 AM
|- - Rob Pinnegar   QUOTE (edstrick @ Oct 12 2006, 04:18 AM) ...   Oct 12 2006, 02:20 PM
- - RNeuhaus   QUOTE (nprev @ Oct 11 2006, 02:06 PM) ......   Oct 12 2006, 02:49 PM
|- - JRehling   QUOTE (RNeuhaus @ Oct 12 2006, 07:49 AM) ...   Oct 12 2006, 04:08 PM
|- - Rob Pinnegar   Hmmm. Would a satellite small enough to avoid disi...   Oct 12 2006, 04:58 PM
|- - RNeuhaus   QUOTE (JRehling @ Oct 12 2006, 11:08 AM) ...   Oct 12 2006, 06:53 PM
|- - JRehling   QUOTE (RNeuhaus @ Oct 12 2006, 11:53 AM) ...   Oct 12 2006, 08:25 PM
- - Bill Harris   QUOTE My initial thought was "but that requir...   Oct 12 2006, 03:42 PM
- - DonPMitchell   According to dynamics calculations by Alexandre Co...   Oct 12 2006, 07:36 PM
- - nprev   Interesting...but how about Mars' relatively r...   Oct 13 2006, 04:55 AM
|- - RNeuhaus   QUOTE (nprev @ Oct 12 2006, 11:55 PM) Int...   Oct 13 2006, 06:59 PM
- - nprev   Well, I'll be...I actually didn't know tha...   Oct 14 2006, 12:14 AM
|- - JRehling   QUOTE (nprev @ Oct 13 2006, 05:14 PM) Wel...   Oct 14 2006, 02:24 AM
- - nprev   Argh...my apologies for misunderstanding you, RN. ...   Oct 14 2006, 03:45 AM
|- - JRehling   QUOTE (nprev @ Oct 13 2006, 08:45 PM) wha...   Oct 14 2006, 04:59 AM
||- - ugordan   QUOTE (JRehling @ Oct 14 2006, 05:59 AM) ...   Oct 14 2006, 09:21 AM
||- - helvick   That was my thinking too. To nudge this slightly ...   Oct 14 2006, 11:17 AM
||- - JRehling   QUOTE (helvick @ Oct 14 2006, 04:17 AM) T...   Oct 15 2006, 04:59 AM
||- - helvick   QUOTE (JRehling @ Oct 15 2006, 05:59 AM) ...   Oct 15 2006, 06:07 AM
||- - JRehling   QUOTE (helvick @ Oct 14 2006, 11:07 PM) A...   Oct 15 2006, 03:32 PM
|- - RNeuhaus   QUOTE (nprev @ Oct 13 2006, 10:45 PM) Arg...   Oct 15 2006, 12:00 AM
|- - nprev   Delinquent thanks for the great "pocket...   Oct 19 2006, 09:27 AM
|- - diane   QUOTE (nprev @ Oct 19 2006, 05:27 AM) Del...   Oct 20 2006, 10:42 PM
- - Myran   QUOTE JRehling wrote: ...would we be here as an ad...   Oct 16 2006, 11:48 AM
|- - tty   QUOTE (Myran @ Oct 16 2006, 01:48 PM) Hal...   Oct 16 2006, 06:19 PM
|- - JRehling   QUOTE (tty @ Oct 16 2006, 11:19 AM) In ea...   Oct 16 2006, 06:35 PM
- - dvandorn   Here's a question: If this model is correct a...   Oct 21 2006, 02:11 AM
- - tasp   QUOTE (dvandorn @ Oct 20 2006, 09:11 PM) ...   Oct 21 2006, 02:24 AM
- - Rob Pinnegar   QUOTE (dvandorn @ Oct 20 2006, 08:11 PM) ...   Oct 24 2006, 08:57 PM


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