The Solar System
The Sun. Contains 98% of the mass of the Solar System. Sunspots
and Magnetic Fields
Mercury: The Messenger
mission. The Caloris Basin. Large
impacts.. Compared to
Earth, Mercury’s core is disproportionately large. This suggest that the planet may once have been much
larger and that what we see is what is left over after many violent impacts.
Venus. Surface air pressure 90 atmospheres, mostly CO2. Surface Temperature about 480 °C
(896 °F) because of a runaway Greenhouse effect. This is the worst-case scenario for the buildup of CO2
in the Earth’s atmosphere, out there for everybody to see.
H2SO4. Active volcanos.
Jupiter. Gas giant. No well defined surface. Contains 1% of the mass of the solar system, about
equal to that of the other planets, dwarf planets, asteroid, comets, etc. all taken together. The sheer
mass of Jupiter means that it takes many impacts by comets, e.g.
might otherwise come into the inner Solar System and endanger us. The
Great Red Spot.
Rings. Some of its
Scientists disagree about what processes are responsible for Miranda’s features. One possibility is that the moon may have been smashed apart in some colossal collision, and the pieces then haphazardly reassembled. Another, perhaps more likely, scenario is that the coronae are sites of large rocky or metallic meteorite strikes which partially melted the icy subsurface and resulted in episodic periods of slushy water rising to Miranda’s surface and refreezing.
Neptune: Just finished its first orbit around the Sun since its discovery in 1846. Happy Birthday! Very
The Pluto system. Ready is firmly in the Pluto-is-not-a-planet camp. [So am I]. One more reason for this
is that the Moons of Pluto do not rotate around Pluto.
Instead Pluto and its moons rotate around a common
barycenter that is beyond the surface of
Pluto. I.e. Pluto is simply the largest of a group of bodies revolving around the same point in empty space.
There may be other, smaller, objects there, possibly enough to endanger the New Horizons
mission. NASA may change the spacecraft’s trajectory through the Pluto system to improve its chances of
Other Kuiper Belt objects.