29:52 Homework Set #4
Assigned: November 19, 2001
Due: November 30, 2001
Confused? Don’t go around miserable and despondent! Ask
for help and explanation from me. Even better, work on these problems with one
or two of your classmates.
- In class I said that the Galilean
satellites of Jupiter obey Kepler’s
3rd Law as they move in their orbits around
Jupiter. It must be remembered
that since the mass of Jupiter is different than the mass of the Sun, you cannot express it as a simple
relation between powers of the semimajor axis in astronomical units and
the period in years. Demonstrate
that the Galilean satellites do obey Kepler’s 3rd Law.
- Physicists
say liquid metallic hydrogen is a good conductor of electricity (like
copper). Give an observed property
of Jupiter which is consistent with this
statement.
- It is
generally believed that an iron and silicon core exists at the very center
of Jupiter and Saturn. Mention a
physical process (invoked in earlier discussions in this course) that
would explain the existence of such cores. If you can use the technical name for this process, that would be great.
- The
Leonid meteors are best seen between midnight and dawn. This should tell you if the orbits of
the “comet pieces” associated with the Leonids are on prograde orbits,
i.e. orbiting in the same direction as the orbital motion of the Earth and
the major planets, or retrograde orbits in which they
orbit in the opposite direction.
Explain your reasoning.
- A
meteor moves on an orbit in the solar system prior to encountering the
Earth. Make an accurate drawing of
a plausible meteor orbit,
explaining the principle features you have drawn.