The Origins of Life on Earth

The video explores how we compute age, contrasting it with the complexity of determining Earth's age. Historically, Earth's age was believed to be only a few thousand years, but modern science estimates it to be around 4.6 billion years. The nebular theory, a widely accepted explanation, suggests that Earth and the solar system formed from a nebula, a cloud of gas and dust, following a supernova explosion. This process led to the formation of the Sun and planets, with Earth being the third planet from the Sun.

How did scientists' beliefs about Earth's age change over time?

• Their beliefs have remained unchanged.

• They always believed Earth was billions of years old.

• They initially thought Earth was a few thousand years old, but now believe it is billions of years old.

• They believed Earth was billions of years old, but now think it is younger.

What is the nebular theory?

• A theory that Earth was formed by volcanic activity.

• A theory that Earth was formed by a giant asteroid impact.

• A theory that Earth was created by a divine being.

• A theory that Earth and the solar system developed from a nebula after a supernova explosion.

What event is believed to have triggered the formation of our solar system according to the nebular theory?

• A volcanic eruption on Earth.

• The cooling of the Sun.

• A collision with another galaxy.

• A supernova explosion near a nebula.

How did the planets, including Earth, form according to the nebular theory?

• They formed from the cooling of the Sun.

• They were created by a series of volcanic eruptions.

• They formed from clumps of matter revolving around the Sun.

• They were shaped by the gravitational pull of the Moon.

Approximately how old do scientists believe Earth is?

• 2.8 billion years

• 1.2 billion years

• 6.4 billion years

• 4.6 billion years