Solar System Dynamics and Exoplanet Science

Posted on May 16, 2026 in Geology

The Jovian Planets

Jupiter: Largest planet, composed of hydrogen and helium.
Juno Mission: Orbiter powered by solar panels.
Rotation: Fast, completing a rotation every 10 hours.
Atmosphere: Bright, reflective cloud bands containing water, ice, and ammonia; colors result from organic molecules caused by convection.
Great Red Spot: Anticyclonic storm caused by ammonia interacting with UV radiation.
Magnetic Field: 20,000 times stronger than Earth’s; aurorae observed near poles in UV.
Rings: Thin, composed of rock dust; visible primarily in infrared.
Io: Thin sulfur atmosphere, yellow appearance.
Europa: Few craters, potential tectonic activity, thin oxygen atmosphere.
Ganymede: Largest moon, possesses a magnetic field and thin oxygen atmosphere.

Saturn: Lowest density planet.
Atmosphere: Ammonia clouds with banded patterns and a north pole hexagon.
Magnetic Field: Sufficient to form polar aurorae.
Rings: Thin, composed of reflective solid ice pieces.
Moons: 274 total; Titan features a thick atmosphere and solid surface of ice and methane.
Carolyn Porco: Led the Cassini imaging science team, exploring ring features.
Ice Giants (Uranus & Neptune): Unique appearances driven by atmospheric composition.
Axial Tilt: Uranus (98°) and Neptune (30°).
Rings: Uranus (icy with carbon, narrow, low reflectivity); Neptune (dusty, non-uniform).
Moons: Uranus (27), Neptune (14); Triton (rock/ice, orbits backwards).
Voyager 2 Mission: Provided critical data on the outer planets.

Definition of a Planet: Must orbit the Sun, be nearly round, and have cleared its orbit.
Dwarf Planets: Orbit the Sun and are round, but do not clear their orbit and are not moons (e.g., Pluto).
Pluto: Rocky and icy surface with potential tectonic activity; thin atmosphere present at perihelion.
Pluto’s Moons: Five total; Charon is the largest, locked in a double tidal lock.
New Horizons: Space probe that performed the first close-up flyby of Pluto.
Other Dwarf Planets: Ceres (largest in asteroid belt), Eris, Haumea, and Makemake.

Location: Between the orbits of Mars and Jupiter.
Characteristics: Revolve in the same direction as planets; very small total mass.
Discovery: Identified by comparing images of the same sky region over time.
Types: Trojans (reside in Jupiter’s gravitational balance points) and Apollo asteroids (NEA with eccentric, Earth-crossing orbits).
Planetary Defense: Detecting risks from NEOs that could impact Earth.

Structure: Nucleus (fluffy ice and dust), Coma (evaporated material), and Tail (points away from the Sun).
Origin: Oort Cloud (beyond Kuiper Belt) and Kuiper Belt (beyond Neptune).
Maria Mitchell: First American to discover a comet and first female astronomy professor.

Terminology: Meteoroid (small rock in space), Meteor (rock burning in atmosphere), Meteorite (rock that hits the ground).
Meteor Showers: Earth encountering debris left behind by an orbiting comet.
Solar Nebula Theory: The Sun and planets formed from the collapse of a rotating cloud of gas and dust.
Accretion: Gravitational accumulation of debris onto a central body.
Planetesimals & Protoplanets: Growing bodies of material that eventually form planets.

Protoplanetary Disk: Flattened disks of gas and dust surrounding new stars.
Detection Methods: Direct detection (IR), Radial velocity (Doppler wobble), and Transit method (brightness dips).
Classification: Super-Earths, Mini-Neptunes, and Hot Jupiters.
Key Figures: Debra Fischer (multi-planet systems), Sara Seager (biosignatures), and Annie Jump Cannon (stellar classification).

Composition: 74% hydrogen, 23% helium.
Helioseismology: Studying the solar interior via wave measurements.
Core: Energy produced via nuclear fusion (hydrogen to helium).
Structure: Radiative zone (energy leaks via radiation) and Convective zone (energy transported by rising/sinking material).
Gravitational Equilibrium: Radiation pressure balances gravity’s collapse.