Home
Class 8
PHYSICS
Cosmic or galactic year is...

Cosmic or galactic year is

A

Year in which a comet arrives

B

Period taken by Earth to revolve around the sun

C

Year in which total solar eclipse occurs

D

Period of Sun's revolution around galactic centre

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding the Concept of a Cosmic Year:** - A cosmic or galactic year refers to the time it takes for the Sun to complete one full orbit around the center of the Milky Way galaxy. 2. **Identifying the Components:** - The solar system, which includes the Sun and its planets, is part of the Milky Way galaxy. - The Milky Way is a vast collection of stars, gas, dust, and dark matter. 3. **Defining the Galactic Center:** - The center of the Milky Way galaxy is a point around which the Sun and other stars orbit. 4. **Calculating the Duration:** - The duration of a cosmic year is approximately 225-250 million Earth years, which is the time it takes for the Sun to make one complete revolution around the galactic center. 5. **Conclusion:** - Therefore, the cosmic or galactic year is defined as the period of the Sun's revolution around the galactic center. 6. **Selecting the Correct Option:** - From the given options, the correct answer is option D: "the period of the Sun's revolution around the galactic center."
Promotional Banner

Similar Questions

Explore conceptually related problems

Cosmic rays (atomic nuclei stripped bare of their electrons) would continuously bombard Earth's surface if most of them were not deflected by earth's magnetic field. Given that earth is, to an excellent approximation, a magnetic dipole, the intensity of cosmic rays bombarding its surface is greatest at the

Cosmic rays are charged particles that strike out atmosphere from some external source. We find that more low-energy cosmic rays reach the earth at the north and south magnetic poles than at the (magnetic) equator. Why it is so?

Due to the earth's magnetic field, charged cosmic ray particles

A: The electrical. Conductivity of the Earth's atmosphere does not change with altitude. R : Cosmic rays from outer space entering the earth's atmosphere do not affect it.

The Sun, which is 2.2 xx 10^20 m from the center of the Milky Way galaxy, revolves around that center once every 2.5 xx 10^8 years. Assuming each star in the Galaxy has a mass equal to the Sun's mass of 2.0 xx 10^30 kg, the stars are distributed uniformly in a sphere about the galactic center, and the Sun is at the edge of that sphere, estimate the number of stars in the Galaxy.

While assessing income tax, the year next to a financial year is called _______ year for that financial year.

Cosmic Panspermia theory was proposed by