Solar System Quiz for 7th Grade Science

A celestial body that orbits a star, has sufficient mass to be nearly round, and has cleared its orbital path of other objects.

The eight major planets in our solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Planets made of rock and metal with a solid surface, like Earth. They are typically smaller and denser than Jovian planets.

Planets composed primarily of gases like hydrogen and helium, with no solid surface. They are much larger and less dense than Terrestrial planets.

Pluto was reclassified as a dwarf planet because it doesn't meet the criteria of clearing its orbital path.

Pluto is now categorized as a dwarf planet because it doesn't meet the criteria of having cleared its orbital path of other objects.

The Earth's magnetic field is a shield generated by its molten iron core, protecting us from harmful solar radiation.

Jupiter is the largest planet in our solar system, with a mass greater than all other planet's combined.

Mercury is the only terrestrial planet without an atmosphere. Its surface is extremely hot. However, frozen water exists in permanently shaded craters near its poles.

Venus has a thick, hot atmosphere made primarily of carbon dioxide. Clouds permanently cover its surface, making it invisible from Earth.

Earth, Venus, and Mars are the only terrestrial planets with significant atmospheres. Earth's atmosphere is essential for life.

Saturn's most prominent feature is its extensive ring system. The rings are made of ice particles of various sizes.

Jupiter's moon Io is incredibly volcanically active. Tidal forces from Jupiter generate immense heat.

Europa, a moon of Jupiter, is covered with a smooth layer of ice. It's believed to have a deep ocean of liquid water beneath the ice.

Ganymede, Jupiter's largest moon, has diverse surface features like mountains, valleys, and craters. It is suspected to have a hidden ocean.

Callisto, a moon of Jupiter, is heavily cratered. Its surface hasn't changed significantly since its formation.

Celestial bodies formed from gas clouds, orbiting the Sun. They develop a bright atmosphere called a coma when approaching the Sun, and often exhibit dust and ionized gas tails. The tails always point away from the Sun.

The process where ice in a comet sublimates into gas when it approaches the Sun, creating a bright atmosphere around the comet's nucleus.

Small celestial bodies that enter Earth's atmosphere and burn up due to friction, creating a bright streak of light.

A meteor that survives its journey through Earth's atmosphere and lands on the surface.

Earth's spinning on its axis, resulting in day and night.

Earth's movement around the Sun in an elliptical orbit, resulting in the seasons.

The angle between the Earth's axis and its orbital plane, responsible for the seasons.

The point in Earth's orbit where the Sun's rays hit the equator directly, resulting in equal day and night lengths.

The Earth's orbit around the Sun takes approximately 365 days and 5 hours and 48 minutes to complete. This slight difference from a full 365 days is the reason we have leap years.

June 21st marks the summer solstice in the Northern Hemisphere, the day with the longest daylight hours.

September 21st is the autumnal equinox, when the Northern Hemisphere experiences equal hours of day and night.

December 21st is the winter solstice in the Northern Hemisphere, the day with the shortest daylight hours.

Leap years occur every four years, where February has 29 days instead of 28. This accounts for the extra time taken for the Earth's orbit.

Time zones are 24 regions around the globe, each with a distinct time. The Greenwich Meridian serves as the central axis, with each zone adding an hour as you move East and subtracting an hour as you move West.

Traveling long distances by airplane can disrupt your body's natural sleep-wake cycle, causing symptoms like fatigue and disorientation. This is commonly known as jet lag.

The Greenwich Meridian is the zero-degree longitude line, serving as the primary reference for determining time zones. It runs through Greenwich, England.

The natural satellite of Earth, orbiting in a defined path due to Earth's gravitational pull. It's about 1/4th the size of Earth in diameter and 1/8th in weight. It lacks air and water, and its surface is marked by craters, mountains, and loose dirt. It experiences extreme temperature variations with very hot days and extremely cold nights.

A theory suggesting that the Earth and Moon initially formed as a single, rapidly rotating body. This body eventually split into two distinct entities.

A theory that the Moon was separated from the Earth, originating from the material that would later become the Pacific Ocean.

The most widely accepted theory proposing that a Mars-sized object collided with the young Earth, blasting a large portion into space. This ejected material eventually coalesced into the Moon.

These are celestial objects composed of ice and dust. They often leave a visible trail of gas and dust as they orbit the Sun.

A collection of rocky debris revolving between the orbits of Mars and Jupiter, which didn't form into a planet.

A celestial object that failed to become a planet. It's the largest asteroid and has about 800km diameter.

Collisions between Earth and asteroids can have devastating impacts. It's believed that one such collision caused the extinction of dinosaurs.

The area on Earth where the sun is directly overhead at noon.

The two days of the year when the sun is farthest from the equator, resulting in the longest (summer solstice) and shortest (winter solstice) days.

An event that happens when the Moon passes between the Sun and Earth, blocking out the Sun's light.

An event that happens when the Earth passes between the Sun and Moon, casting its shadow on the Moon.

The darkest, central part of a shadow.

The lighter, outer part of a shadow.

The path of the Moon around Earth.