"These differences are not just [due] to Venus being closer to the sun," Oxford's Taylor says. "We now know that the lack of a protective magnetic field and the differing planetary rotation rates also play a role in ensuring that many of the atmospheric processes we observe on Earth occur at a much faster rate on Venus. Our new data make it possible to construct a scenario in which Venus started out like the earth [did]—possibly including a habitable environment, billions of years ago—and then evolved to the state we see now."

Jumbotron image: ESA/VIRTIS-VenusX/INAF-IASF/Obs. de Paris-LESIA (P. Drossart, Obs. de Paris-LESIA)

6 Comments

1. 1. prenderman 04:03 PM 11/30/07

   The subheadline is a joke, right?

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2. 2. wonderwhy 12:24 AM 12/9/07

   No magnetic field, but a twin Earth? Core? Land mass? How do you justify the headline?

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3. 3. Guardian54 12:24 AM 12/10/07

   1. Venus and Earth form.
   2. Venus hit by giant rock, slowing spin.
   3. Venus unable to cool down with slow spin, lose water
   4. core stops dynamo work, magnetism disappears
   5. Current day

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4. 4. Guardian54 12:25 AM 12/10/07

   Oh, and also, a kid abused almost to death since birth isn't gonna be the same as an identical twin treated well with a good education

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5. 5. jtdwyer in reply to David Cota 04:09 AM 12/18/10

   Good comment! Once again I agree, but with a few suggestions:
   3 - Despite the obvious accumulated evidence of Lunar impacts, I doubt that the moon's gravitational field (without a heavy core) is strong enough to attract most impact events headed towards the Earth. I think that a small body object directed to the Earth-moon systems at high relative velocity would most likely hit the larger Earth with its much greater gravitational effect. Keep in mind that, relative to any approaching object, the moon is nearest to the object less than half of the time and, as mentioned, the much more massive iron core Earth's gravitational effect is much greater.
   
   In addition, the Solar wind's affect on Venus' atmosphere, observed to be stripping away both its hydrogen and oxygen, currently observed to produce a comet-like coma extending to the Earth's orbit, may have contributed to Earth a significant amount of the elemental components of our water. While Venus may have rarely been aligned with the Sun and Earth such that its coma could have delivered oxygen and hydrogen into the Earth's magnetosphere, those elements would be much more massive and less energetic than the radical particles contained within the Solar wind. This is just an interesting possibility I don't think has been considered...

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6. 6. Percival 05:48 PM 4/18/13

   I'd still like to now why Venus has such high winds. One would think that friction with the surface would damp them down after a few million years. What keeps them going?

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