Observable Universe

The observable Universe is the furthest we can see with the largest telescopes, because light (or other signals) from those objects has had time to reach us.

Universe - facts 7

The diameter of the observable Universe is currently estimated to be 93 billion light years. This is approximately 558,000,000,000,000,000,000,000 miles (558 sextillion miles).

Velocity

Velocity is how fast an object is moving in a given direction.

Galaxies - facts 8

Some galaxies are as far as 13 billion light years away from us.

Galaxy

A galaxy is made up of a massive amount of gas, dust, stars, planets, and other objects. They are held together by their own gravity.

Homogeneously

Homogeneously means that the matter in the Universe is spread uniformly when averaged over large distances.

Extrasolar planet

An extrasolar planet is a planet that is outside the Solar System.

Super-Earth

A super-Earth is an extrasolar planet that has a mass higher than Earth's but less than the gas giants in the Solar System.

Quasar

A quasar is a very distant object that is extremely luminous and looks star-like in appearance.

Supercluster

A supercluster is a very large group of galaxy clusters.

Space time

Space time is space and time existing together in the Universe.

Absolute zero

Absolute zero is the lowest theoretical temperature possible. It is 0 on the Kelvin scale. This is -459.67 degrees Fahrenheit or -273.15 degrees Celsius.

Jupiter - trivia 3

1) In what direction does the Great Red Spot on Jupiter rotate?

a) clockwise
b) counterclockwise
c) stationary

Check comments for the answer.

Cosmic microwave background radiation

Cosmic microwave background radiation is radiation that fills the entire Universe, believed to be left over from the Big Bang.

Intergalactic space

Intergalactic space is the space between galaxies.

Elementary particle

An elementary particle is a particle that cannot be subdivided into anything smaller.

Earth - facts 12

Earth is the third planet from the Sun.

Titan - facts 3

Titan is the only moon in the Solar System with a thick atmosphere.

Ganymede - facts 2

Ganymede is the largest moon in the Solar System.

Ganymede - facts 1

Ganymede was discovered by Galileo Galilei in 1610.

Jupiter - facts 8

The largest moon of Jupiter is Ganymede.

Neptune - facts 4

Neptune is named after the Roman god of the sea.

Uranus - facts 4

Uranus is named after the ancient Greek god of the sky.

Mars - facts 12

Mars is named after the Roman god of war.

Saturn - facts 5

Saturn is named after the Roman god of agriculture and the harvest.

Titan - facts 2

Titan is the second largest moon in the Solar System.

Titan - facts 1

Titan was discovered by Christiaan Huygens in 1655.

Saturn - facts 4

The largest moon of Saturn is Titan.

Earth - facts 11

The diameter of the Earth is approximately 7,918 miles.

Sun - facts 13

The diameter of the Sun is approximately 864,400 miles.

Sun - facts 12

The Sun's diameter is approximately 109 times as big as the diameter of Earth.

Light speed

The speed of light is approximately 186,000 miles per second. This is how far light travels each second. A light year is how far light travels in a year.

Sun - facts 11

A solar flare is a large eruption in the Sun's atmosphere.

Meteor

A meteor is the visible path of a meteoroid that has entered the Earth's atmosphere and burns up.

Planets - facts 14

Planets do not give off their own light. They shine from the light of their star.

Planets - facts 13

Planets are round shaped because of gravity.

Planet

A planet is a round celestial body that revolves around a star. Planets are round because of gravity. A planet is illuminated by the light from its star.

Gravity

Gravity is the force of attraction between all masses in the Universe.

Dark matter

Dark matter makes up approximately 25% of the Universe. It is matter in the Universe that cannot be seen, but is detected by gravitational effects on other bodies.

Dark energy

Dark energy makes up over 70% of the Universe. Dark energy is believed to increase the rate of expansion of the Universe.