2007-12-08 22:06:03 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
A planet like ours has a magnetic field for two reasons -- 1. Its core is molten metal; 2. It rotates which 'stirs up' the metallic core so that it acts like a dynamo from which a magnetic field is generated. Venus appears to also have a molten core, but its rotational period is 240 days compared to our 24 hours. Because of its very slow rotation, no significant dynamo effect occurs, thus no significant magnetic field.
2007-12-08 22:42:47 · answer #1 · answered by Chug-a-Lug 7 · 3⤊ 1⤋
Magnetic fields are produced by large lumps of molten iron moving around. Venus, while it has a similar composition to Earth, lacks the internal movement, and plate tectonics of Earth, so a magnetic field is extremely weak, or absent.
2007-12-08 22:25:05 · answer #2 · answered by Labsci 7 · 2⤊ 1⤋
Why does Venus lack a magnetic field?
http://ocw.mit.edu/NR/rdonlyres/Earth--Atmospheric--and-Planetary-Sciences/12-570Spring-2005/B048CA70-465A-4844-82B4-4B3D9720AFCA/0/grp1vensmgntcfld.pdf
2007-12-08 22:12:42 · answer #3 · answered by a bush family member 7 · 2⤊ 0⤋
It was formed by the collection of space dust and not by massive iron based asteroids colliding with primal Venus!
2007-12-09 01:07:53 · answer #4 · answered by Anonymous · 0⤊ 1⤋
reason 1)
Perhaps because of its slow rotation.
reason2)
The core of Venus doesn't have any siderophile elements.
2007-12-09 02:11:34 · answer #5 · answered by An ESL Learner 7 · 0⤊ 0⤋