Physics ยท Science General

Astronomy and Cosmology

4,450 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

Which radiative process is responsible for the formation of polycyclic aromatic hydrocarbons (PAHs) in the interstellar medium?

  1. Photoionization

  2. Photodissociation

  3. Photoexcitation

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

Photoexcitation, the absorption of radiation by a molecule resulting in the promotion of an electron to a higher energy level, is the primary process responsible for the formation of polycyclic aromatic hydrocarbons (PAHs) in the interstellar medium.

Multiple choice

What is the primary source of infrared radiation in the interstellar medium?

  1. Hot stars

  2. Dust grains

  3. Molecular clouds

  4. Cosmic rays
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Dust grains, small solid particles in the interstellar medium, are the primary source of infrared radiation, as they absorb and re-emit starlight in the infrared wavelength range.

Multiple choice

What is the primary source of gamma-ray radiation in the interstellar medium?

  1. Hot stars

  2. Dust grains

  3. Molecular clouds

  4. Cosmic rays
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cosmic rays, high-energy particles from outside the solar system, are the primary source of gamma-ray radiation in the interstellar medium, as they interact with interstellar gas and dust, producing gamma rays through various processes.

Multiple choice

According to Dr. Subrahmanyan Chandrasekhar's 'Stellar Evolution Theory', what happens to a star when it exhausts its nuclear fuel?

  1. It becomes a white dwarf.

  2. It collapses into a neutron star.

  3. It explodes as a supernova.

  4. It transforms into a black hole.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Dr. Subrahmanyan Chandrasekhar's 'Stellar Evolution Theory' explains that when a star exhausts its nuclear fuel, it collapses under its own gravity, resulting in the formation of a neutron star.

Multiple choice

According to Dr. Subrahmanyan Chandrasekhar's 'Chandrasekhar Limit', what is the maximum mass a white dwarf star can have before collapsing into a neutron star?

  1. 1.4 solar masses

  2. 3.0 solar masses

  3. 0.5 solar masses

  4. 2.5 solar masses
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dr. Subrahmanyan Chandrasekhar's 'Chandrasekhar Limit' states that a white dwarf star cannot exceed 1.4 solar masses before collapsing under its own gravity and becoming a neutron star.

Multiple choice

Which of the following instruments is NOT part of the Hubble Space Telescope?

  1. Wide Field and Planetary Camera 2 (WFPC2)

  2. Advanced Camera for Surveys (ACS)

  3. Cosmic Origins Spectrograph (COS)

  4. James Webb Space Telescope (JWST)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The James Webb Space Telescope (JWST) is a separate space telescope with different instruments and capabilities. It is not part of the Hubble Space Telescope.

Multiple choice

What was the Hubble Deep Field (HDF) project?

  1. A study of the formation of stars and galaxies in the early universe

  2. An attempt to detect extraterrestrial life

  3. A mission to repair the Hubble Space Telescope

  4. A survey of the Milky Way galaxy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Hubble Deep Field (HDF) project was a groundbreaking observation that captured an extremely deep and detailed image of a small region of space, revealing distant galaxies and providing insights into the early universe.

Multiple choice

Which Hubble Space Telescope observation provided evidence for the existence of supermassive black holes at the centers of galaxies?

  1. The Hubble Ultra Deep Field (HUDF)

  2. The Hubble Space Telescope Key Project on Galaxies

  3. The Hubble Space Telescope Survey of Active Galactic Nuclei

  4. The Hubble Space Telescope Imaging Survey of Nearby Galaxies
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Hubble Space Telescope Key Project on Galaxies provided evidence for the existence of supermassive black holes at the centers of galaxies by observing the motions of stars and gas near the centers of these galaxies.

Multiple choice

Which Hubble Space Telescope observation provided evidence for the existence of an Earth-like planet orbiting a Sun-like star?

  1. The Hubble Space Telescope Planet Search

  2. The Hubble Space Telescope Exoplanet Survey

  3. The Hubble Space Telescope Kepler Mission

  4. The Hubble Space Telescope Transiting Exoplanet Survey Satellite (TESS)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Hubble Space Telescope Kepler Mission was an observation that discovered thousands of exoplanets, including the first Earth-like planet orbiting a Sun-like star.

Multiple choice

Which Hubble Space Telescope observation provided evidence for the existence of a massive black hole at the center of our galaxy, the Milky Way?

  1. The Hubble Space Telescope Milky Way Center Survey

  2. The Hubble Space Telescope Milky Way Black Hole Search

  3. The Hubble Space Telescope Milky Way Stellar Dynamics Survey

  4. The Hubble Space Telescope Milky Way Gas and Dust Survey
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Hubble Space Telescope Milky Way Center Survey was an observation that provided evidence for the existence of a massive black hole at the center of our galaxy, the Milky Way, by studying the motions of stars near the center.

Multiple choice

What is the estimated percentage of dark matter in the universe?

  1. 27%

  2. 68%

  3. 4%

  4. 11%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dark matter is estimated to make up approximately 27% of the universe's mass and energy.

Multiple choice

What is the name of the international collaboration that is working to build a dark matter detector?

  1. LUX-ZEPLIN

  2. PandaX-4T

  3. XENONnT

  4. DarkSide-20k
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

LUX-ZEPLIN is an international collaboration that is working to build a dark matter detector.

Multiple choice

What is the expected timeline for the detection of dark matter?

  1. Within the next 10 years

  2. Within the next 20 years

  3. Within the next 50 years

  4. Never
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The expected timeline for the detection of dark matter is within the next 20 years.

Multiple choice

What is the Hubble Space Telescope's main scientific instrument?

  1. Wide Field and Planetary Camera 2 (WFPC2)

  2. Advanced Camera for Surveys (ACS)

  3. Space Telescope Imaging Spectrograph (STIS)

  4. Cosmic Origins Spectrograph (COS)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Wide Field and Planetary Camera 2 (WFPC2) was the Hubble Space Telescope's main scientific instrument at launch and was responsible for capturing many of the telescope's most iconic images.

Multiple choice

What is the Hubble Space Telescope's most significant contribution to cosmology?

  1. Measuring the expansion rate of the universe

  2. Determining the age of the universe

  3. Discovering dark matter

  4. Observing the first galaxies
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Hubble Space Telescope's most significant contribution to cosmology is its measurement of the expansion rate of the universe, which led to the discovery of the accelerating expansion of the universe.