Science Final Review: Exploring Our Universe

A set of vocabulary flashcards covering solar system formation, types of celestial bodies, star life cycles, and planetary motions based on the lecture notes.

Sol

Located in the middle of the Solar System, it formed from a giant cloud of gas and dust that collapsed over its own gravity, becoming denser and hotter until nuclear fusion formed in its core; a bright star composed of hydrogen + helium.

Inner planets

Also known as Terrestrial Planets (Mercury, Venus, Earth, Mars), these have a hard + rocky surface made with iron, nickel, metal, and rock.

Outer planets

Also known as Gas giants (Jupiter, Saturn, Uranus, Neptune), these are farthest from the sun and are composed of liquid and gases like hydrogen and helium.

Asteroids

Objects smaller than dwarf planets + moons that are not big enough to form a spherical shape and are irregularly shaped.

Comets

Chunks of ice, dust, and rock that orbit the Sun in long elliptical paths, featuring two tails (one from the sun and one from debris).

Black holes

Astronomical objects with a gravitational field so intense that nothing can escape it, formed when massive stars collapse at the end of their life cycle.

Meteroids

Small pieces of rock/metal (space rock).

Meteors

A meteroid that enters earth's atmosphere.

Meteorites

A meteroid that hits earth's surface.

Protostar

A young star that is developing; a celestial body representing the earliest stage in a star's life where the core becomes hot and nuclear fusion starts.

Main Sequence

A star in the longest, stable phase of its lifecycle that fuses hydrogen + helium in the core.

Red Giant

A big, red star near the end of its life that forms when a star runs out of hydrogen fuel and heat makes outer layers expand.

Hertzprung-Russel Diagram

A graph that compares a stars temperature to its luminosity and helps scientists group stars + understand their life cycles.

Astroid Belt

A wide ring-shaped region between Mars + Jupiter filled with millions of rocky debris left over from the past formation of our solar system.

Kuiper Belt

A giant ring beyond the Gas Giants that holds dwarf planets, meteroids, astroids, and dust.

Oort cloud

A giant cloud that shows the boundary of the Solar System and holds billions of comets + space rocks.

Constellations

Groupings of stars that make up a shape of an animal, person, or thing.

Nebulae

The plural form of nebula, used when discussing more than one cloud.

Planetary Nebula

A glowing cloud of dust + gas left behind when a giant red star sheds its outer layers.

White Dwarf

The small, hot core left behind after a star like the sun runs out of fuel and sheds its outer layers.

Black Dwarf

A cold, dark white dwarf that has cooled down completely over a very long time. What a medium-mass star becomes at the end of its life.

Supergiant

An extremely large, very bright star that is near the end of its life cycle.

Supernova

A powerful explosion that happens when a massive star dies.

Neutron Star

The super dense core left after a massive star explodes in a supernova.

Rotation

When an object spins around its own axis.

Revolution

When an object moves in a path around another object in space.

Seasons

Changes in weather and daylight caused by Earths tilt as it orbits the sun.

Equinox

Occurs when day and night are nearly equal in length.

Solstice

Occurs when Earths tilt causes the sun to reach its highest / lowest point in sky, creating the longest + shortest days of the year.

Moons

Natural satellites that orbit planets / dwarf planets.

Dwarf planets

Celestial bodies that orbit the Sun, are almost round, but have not cleared the orbital path of past debris (examples: Ceres, Mane Make, Hamaea, Eres, Pluto).

Solar System Formation

Solar system formed when a star exploded creating planets and other rocks, gas, liquid formation that gravity pulled together, forming our solar system