The total journey time from Earth to Mars takes between 150-300 days depending on the speed of the launch, the alignment of Earth and Mars, and the length of the journey the spacecraft takes to reach its target. It really just depends on how much fuel you’re willing to burn to get there. More fuel, shorter travel time.
Why do some planets have rings?
One theory is that the rings formed at the same time as the planet and its major moons. In this case, if material is close to the planet, the planet’s gravitational pull is too strong to coalesce into a moon and the particles that would otherwise form a moon spread out in orbit around the planet as a ring.
Another idea is that a close call by a moon or comet results in the planet's gravitational tidal force breaking up those bodies, the debris of which then becomes a ring system.
Although astronomers can't say for certain what causes planetary rings, Lattis says that the Cassini spacecraft now in orbit around Saturn is beginning to provide tantalizing new clues to the forces that govern the physics of planetary rings.
By : Lucia 6ºB
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