Physics · Science General

Astronomy and Cosmology

4,498 Questions

This topic provides questions on astronomy, cosmology, and the physical universe. It covers subjects like the Hubble sequence, constellations, dark matter, and stellar evolution. These questions help build a strong foundation for general science exam sections.

Galaxies and clustersConstellations and starsStellar evolutionSpace observatories

Astronomy and Cosmology Questions

Multiple choice physics constellations and galaxies light year evolution and end stages of stars in the world of stars

The nearest star to the Earth (apart from the Sun) is 'alpha centauri' which is about .......... away form the Earth

  1. 4.3 light years

  2. 3.26 light years
  3. $4.3 \times 10^{12}$ km
  4. $3.26 \times 10^{15}$ km
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Alpha century is a star system closest to earth other than sun. Its distance from the earth is about $4.367$ light years.

Multiple choice physics constellations and galaxies light year evolution and end stages of stars in the world of stars

How does astronomer calculate distance of star?

  1. Comparing apparent brightness of star to true brightness

  2. Comparing true brightness of star to apparent brightness

  3. Comparing true brightness of star to true brightness

  4. None
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The brightness of the stars changes over time. The difference in the brightness (difference in the apparent brightness to the true brightness) over the time allows calculating the distance to the star. This is the cepheid variable stars method that is used to measure the distance to stars beyond 100 light years.

Comparing the apparent brightness of the star to true brightness

Multiple choice evs our earth and the space asteroids, comets, and meteors and meteorites other objects in solar system asteroids, comets and meteors

Fill in the blank:

A shooting star is a _______.

  1. comet

  2. meteor

  3. meteorite

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Shooting stars look like stars that quickly shoot across the sky, but they are not stars. A shooting star is really a small piece of rock or dust that hits Earth's atmosphere from space. It moves so fast that it heats up and glows as it moves through the atmosphere. Shooting stars are actually what astronomers call meteors. Most meteors burn up in the atmosphere before they reach the ground. However, once in a while a meteor is large enough than some of it survives and reaches Earth's surface. Then it is called a meteorite.
Hence, shooting star is a common name for the visible path of a meteoroid as it enters the atmosphere, becoming a meteor.

Multiple choice physics movement of the earth properties of stars life cycle of stars solar system and its planets types of galaxies galaxies

Why does sun appear larger than other stars to us?

  1. It is larger than other stars.

  2. It is farther than other stars.

  3. It is closer than other stars.

  4. It is faster than other stars.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sun is much closer to us as compared to other stars. Hence, it subtends larger angle at eyes compared to other stars and appear larger. Note that many stars are much larger than sun in size.

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

The evidence for the rotation of stars comes mainly from the.

  1. Stark effect

  2. Photoelectric effect

  3. Doppler effect

  4. Zeeman effect
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Doppler effect causes shifts in the spectral lines of a rotating star. As one side of the star rotates toward the observer and the other away, the light is blueshifted and redshifted respectively, causing spectral line broadening.