What are Years... and the Galactic Supermassive Black Hole!

The video explores the concept of a year, defining it as the time it takes for one body to orbit another. It explains different types of Earth years: tropical, sidereal, and anomalistic, each with slightly different lengths. The civil calendar aligns with the tropical year due to its relation to Earth's axial tilt and seasons. The video also discusses non-Earth years, such as Mercury's and Neptune's, and introduces the galactic year, the time for the solar system to orbit the Milky Way. It highlights the short orbits of stars around the Milky Way's central black hole, used to measure its mass.

What is a tropical year defined by?

• The time it takes for the Moon to orbit the Earth

• The time it takes for the Earth to return to the same position in its orbit

• The tilt of the Earth's axis relative to the Sun

• The time it takes for the Earth to orbit the Sun

Why does our civil calendar follow the tropical year?

• Because it is the longest year

• Because it is the shortest year

• Because it aligns with the passage of the seasons

• Because it is based on the Moon's orbit

How long is a year on Mercury compared to Earth?

• 165 Earth years

• 250 million Earth years

• 88 Earth days

• 10 Earth years

What is a galactic year?

• The time it takes for a star to orbit a black hole

• The time it takes for the Earth to orbit the Sun

• The time it takes for the Moon to orbit the Earth

• The time it takes for the solar system to orbit the Milky Way

What have astrophysicists determined about the black hole at the center of the Milky Way?

• It is as massive as 100,000 Suns

• It is as massive as 10 million Suns

• It is as massive as 1 million Suns

• It is as massive as 4 million Suns