Astronomy - Quiz 3

What is our Solar System?

Our celestial neighborhood consisting of the Sun and all objects caught within its gravity.

What is the order of the planets from the Sun?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

What are the inner planets?

Mercury, Venus, Earth, and Mars. They are terrestrial planets with solid rocky surfaces.

What are the outer planets?

Jupiter, Saturn, Uranus, and Neptune. They are Jovian planets made mostly of lighter elements and gases.

What are characteristics of Mercury?

Many craters, cliffs, valleys, little ice, extremely hot during the day and freezing at night.

What are characteristics of Venus?

Volcanoes, deformed mountains, extremely hot surface temperatures.

What are characteristics of Earth?

Rocky planet with liquid water oceans, oxygen-rich atmosphere, active plate tectonics, and 1 moon.

What are characteristics of Mars?

Rocky, dusty, craters, frozen water beneath the surface, colder and drier than Earth, 2 moons.

What are characteristics of Jupiter?

Giant storms, colorful clouds, extremely hot inside, cold outer atmosphere, thick liquid-like interior, 115 confirmed moons.

What are characteristics of Saturn?

Mostly gas, no solid surface, cloud bands, liquid interior from pressure, rings made of water ice.

What are characteristics of Uranus?

Cold, windy, superheated water and gases, bright clouds, at least 21 moons.

What are characteristics of Neptune?

Very windy, cold clouds, methane gas gives blue color, giant storms, possible superheated ocean inside.

Why is Pluto not considered a planet?

Pluto is classified as a dwarf planet.

What are characteristics of Pluto?

Extremely cold, icy, rocky, covered in frost with mountains, glaciers, and frozen oceans.

What is an asteroid?

A rocky or metallic object orbiting the Sun that is smaller than a planet.

What is a meteor?

A streak of light caused when space debris enters Earth’s atmosphere and burns up.

What is a comet?

A cosmic snowball made of frozen gases, rock, and dust that orbits the Sun.

What is the Sun?

A star and luminous ball of gas containing 99.86% of the Solar System’s mass.

What powers the Sun?

Nuclear fusion converting hydrogen into helium.

How large is the Sun compared to Earth?

About 100x Earth’s radius and 300,000x Earth’s mass.

What are sunspots?

Cooler dark regions on the Sun caused by strong magnetic fields.

How long do sunspots usually last?

A few days to over a month.

What are solar flares?

Bright eruptions of hot gas that increase radio and X-ray emissions.

What is a star?

A massive self-luminous ball of gas powered by nuclear reactions.

What is absolute magnitude?

A measure of a star’s true brightness regardless of distance from Earth.

What does a blue star indicate?

A very hot star.

What does a yellow/orange star indicate?

A medium-temperature star.

What does a red star indicate?

A cooler star.

What is an HR Diagram?

A graph comparing stars by brightness and surface temperature.

What is the life cycle of an average star?

Nebula → Main Sequence Star → Red Giant → White Dwarf.

What is the life cycle of a massive star?

Nebula → Protostar → Blue Main Sequence Star → Red Supergiant → Supernova → Neutron Star or Black Hole.

What are stars mainly made of?

About 73% hydrogen and 25% helium with small amounts of heavier elements.