Solar System Astronomical Data

Vocabulary flashcards covering the astronomical data and characteristics of the Sun, planets, moons, and comets in our Solar System.

Moon

A natural satellite of a planetary body (planet or asteroid), such as Earth's only natural satellite.

Moon Surface Gravity

$$1.62\,m/s^2$$

Pluto

A dwarf planet located in the Kuiper Belt, discovered in 1930 and reclassified in 2006 by the International Astronomical Union.

Kuiper Belt

A distant region of icy debris at the edge of our solar system.

Uranus

The seventh planet from the Sun, classified as an ice giant, known for its extreme $98$-degree axial tilt.

Ganymede

The largest moon in the Solar System and the only moon known to have its own magnetic field.

Io

The innermost of Jupiter's four Galilean moons and the most volcanically active body in the Solar System.

Earth

The third planet from the Sun and the only known planet in the Solar System that supports life.

Sidereal Day (Earth)

The period of rotation on Earth's axis, lasting $23$ hours $56$ minutes.

Callisto

The outermost Galilean moon of Jupiter and one of the oldest, most heavily cratered bodies in the Solar System.

Europa

The smallest of the four Galilean moons, believed to have a vast ocean beneath its icy surface.

Jupiter

The largest planet in the Solar System, a gas giant with a Great Red Spot storm and more than 90 known moons.

Mars

The fourth planet from the Sun, known as the "Red Planet" due to iron oxide (rust) on its surface.

Saturn

A gas giant and the sixth planet from the Sun, featuring the largest and most prominent ring system.

Yellow Dwarf

The common name for the Sun, which has a stellar classification of GZV.

Sun's Mass

$1.9885 \times 10^{30}\,kg$, which contains $99.86\%$ of the Solar System's total mass.

Photosphere

An atmospheric layer of the Sun with a temperature of $5,500\,^{\circ}C$ ($5,778\,K$).

Differential Rotation

The type of rotation shown by the Sun where the equator rotates in $24.47$ days while the poles take approximately $35$ days.

Nucleus (Comet)

The solid, central core of a comet, often described as a "dirty snowball," composed of volatile ices, rocky materials, and organic dust.

Coma

The glowing, hazy atmosphere surrounding the nucleus of a comet, formed by the sublimation of ices.

Ion Tail

A stream of electrically charged gas molecules blown away from the coma by the solar wind, always pointing away from the Sun.

Dust Tail

A tail made of tiny dust particles that curves slightly along the comet's orbit and glows with a yellowish-white color.

Halley's Comet (1P/Halley)

A comet with an orbital period of 75-76 years and a retrograde orbit (inclination of $162.3^{\circ}$).

Albedo (Halley's Comet)

Extremely dark reflectivity, reflecting only about $3\%$ of sunlight.