What if Earth had a small close satellite?

(Jaak Suurpere) wrote in message . com...
Earth now has just 1 satellite. Moon.

Yet Mars has 2. Jupiter, Saturn and Uranus each have many.

If Earth had an asteroid-type satellite, what would happen next?

Its orbit would be perturbed, among other things, by Sun, Moon,
Earth's oblacy, Earth's relief and the tidal wave it raises on Earth.

We know that perturbations by Sun do not rule out existence of
satellites for many planets, and perturbations by quite large
satellites do not rule out existence of others.

What orbits could a natural satellite of Earth naturally have,
assuming that Moon has orbit as in OTL?

Mars has a satellite whose orbital period is less than 8 hours.

What would happen if a satellite of Earth crossed the Roche limit?

If it is weak, it could break immediately into a ring. But when the
fragments of the satellite spread out along the orbit, the tidal force
on them would vanish and tidal braking would stop. What would the ring
do next?

If it is strong and small, it would first break into a few large
pieces. These would then orbit for some time on closeby orbits and
undergo collisions at sloew speed. What else can be said about this
process?

Small and strong satellites might ultimately reach atmosphere. If a
large hard rock moves in upper atmosphere at 8 km/s, what are the
effects on ground? What will happen with the smoke in atmosphere? It
is likely that the orbit may be close to equator.

If a large body eventually reaches ground, its speed cannot be over 8
km/s, but probably nor can it be much less. What will the explosion be
like? Will it produce distinctive results that cannot happen if a body
hits Earth on hyperbolic orbit? Will the results be distinctive even
if the final splashdown is in an ocean?

At which geological - or historical - times could the Earth have had
rings or satellites without us knowing about it now?


Depending on what you classify as "close", one word

Cruithne

http://www.google.com/search?sourcei...ent&q=Cruithne