If The interior of Venus is composed of a central iron core and a molten rocky mantle, similar to the composition of Earth, then why isn't Venus projecting a magnetic field too?
A day on Venus (243 Earth days) is longer than a year (224.7 Earth days). The rotation is also opposite from that of Earth, with the Sun rising in the West.
Does the direction and rate of rotation have to do with the lack of a magnetic field?
I don't understand...
I have a Mars Question too...
2007-12-21 01:51:41 · 11 answers · asked by Ophiuchus 3 in Science & Mathematics ➔ Astronomy & Space
It has no satellites. Earth's magnetic field is generated by the gravitational pull of the Moon raising tides in the core. Venus hasn't got this. However, you are also right that the slow rotation is significant, because if it rotated faster the Sun would raise smaller tides and create a field, though weaker. The direction of rotation is not significant.
2007-12-21 04:46:31 · answer #1 · answered by grayure 7 · 0⤊ 2⤋
Venus slow rotation is likely why it's magnetic field is almost non-existent. Most of that does not come from the planet's interior, but the interaction between the Solar wind and the planet's upper atmosphere. On Earth, the rapid rotation coupled with the presence of a layer of liquid, conductive metals gives rise to a strong magnetic field because of eddies and currents in the outer core. Venus is about the same size, mass and bulk composition as the Earth, so it too should have a partially molten core as well. It also would have started plate tectonics but because of it super heating and losing it's oceans, plate tectonics stopped and hot spot volcanism took over.
2007-12-21 02:19:48 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Venus core is probably made up out of the same materials as earths. Venus density suggests this. So the core is most likely as hot as earths too. But magnetic fields require a dynamo effect. Earth gets its from its rotation. Venus hardly rotates at all and has an extremely weak magnetic field in proportion to that rotation. The direction of the rotation is not relevant.
2007-12-21 05:47:20 · answer #3 · answered by DrAnders_pHd 6 · 2⤊ 0⤋
If this is actually the case (I'm not sure at the moment, but I'll check) then I would say that Venus' core isn't acting like a dynamo the way earth's core does.
The molten iron in earth's core spins, which causes a magnetic feild to eminate. Appartently Venus core is not spinning, so there is no magnetic field produced.
Update: Venus DOES have a magnetic field, but it is very weak as compared to earth. Read more at wikipedia.
2007-12-21 02:00:44 · answer #4 · answered by Jared Z 3 · 0⤊ 0⤋
Here are a couple of websites which might be of help:
http://sunearth.gsfc.nasa.gov/sunearthday/2004/vt_venus_planetary_2004.htm
http://www-ssc.igpp.ucla.edu/personnel/russell/papers/venus_mag/
http://ocw.mit.edu/NR/rdonlyres/Earth--Atmospheric--and-Planetary-Sciences/12-570Spring-2005/B048CA70-465A-4844-82B4-4B3D9720AFCA/0/grp1vensmgntcfld.pdf
Most of these describe a ratio of solid core to liquid mantle being unlike that of Earth's, combine with a slow rotation, that acting together do not allowing the convection necessary to generate a strong magnetic field. Venus DOES have a magnetic field, but it is very much weaker (10^-5) than the Earth's.
2007-12-21 02:13:36 · answer #5 · answered by We left and returned! 7 · 1⤊ 0⤋
Pluto cannot have a magnetic field because it is mostly ice. Venus seems to lack a magnetic field. Mercury has a weak one. You ought to taske a look at NASA's website, and click on either a planet, or click on a spacecraft that studied another planet, such as Galileo at Jupiter or MESSENGER at Mercury.
2016-04-10 11:08:19 · answer #6 · answered by Tara 4 · 0⤊ 0⤋
although Venus is similar to earth its core has solidified our earths core mixes and rotates producing a magnetic field. i think that research suggests at one point in the past Venus did produce a field but this diminished when its core stopped. Its been a long time so please correct me if im wrong.
2007-12-21 02:07:11 · answer #7 · answered by Ricky 2 · 0⤊ 0⤋
because its core is not moving/rotating like earth's to produce a magnetic field and the core is frozen while earth's is liquidy like lava
2007-12-21 01:57:43 · answer #8 · answered by Anonymous · 0⤊ 0⤋
because venus doesn't have plates...it's crust is one solid piece. The earths plates allow for the mantle to cool, but since venus' crust is one piece the mantle cannot cool.
2007-12-21 02:02:56 · answer #9 · answered by darcy_t2e 3 · 0⤊ 0⤋
i think the direction of the rotation might have something to do with it because Pluto revolves the same manner and doesn't have one either, it could also be the speed of the rotation as well
2007-12-21 02:02:23 · answer #10 · answered by J 3 · 0⤊ 0⤋