Rocky Planet and Rings
Could a rocky planet have rings like Saturn or Jupiter?
There is no reason why a rocky planet could not have a ring system.
There are several theories of how the rings of Saturn and Jupiter
formed. One of the theories is that the rings are remnants of a moon
that came close enough to the planet so that the tidal forces ripped
it apart. Another is that the rings were formed from collisions of
moons or asteroids. A third theory is that the particles are remnants
from the early formation of the planet itself - particles that did not
merge with the planet.
As you can imagine, depending on which theory is true - and there are
data supporting one theory over another so that it is still too early to
tell which theory is the most likely, then it would answer whether rocky
planets can have rings. If tidal forces is what form rings, than rocky
planets with lower masses might not form rings - or the debris would be
too close to stay in orbit very long. If rings are formed by collisions,
than debris rings can form around any type of planet. If rings are formed
from particles that did not join the planet during its formation, than
again, these rings would have to be at a distance which balances the
gravitational and tidal forces. It's possible to have them around rocky
planets but it would have to be a confluence of several factors that
Greg (Roberto Gregorius)
From the following article on the on-line encyclopedia Wikipedia:
"There are three ways that planetary rings (the rings around planets) have
been proposed to have formed:
1) from material of the protoplanetary disk that was within the Roche limit
of the planet and thus could not coalesce to form moons;
2) from the debris of a moon that was disrupted by a large impact; or
3) from the debris of a moon that was disrupted by tidal stresses when it
passed within the planet's Roche limit."
So, yes, a rocky planet can have rings like Saturn or Jupiter.
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Update: June 2012