ASP MCQ 5

Question 1

What is dark matter?

Accepted Answer

Matter composed of undetected, non-luminous particles that interacts gravitationally

Answer

Dark matter is an undetected form of matter inferred from gravitational effects (galaxy rotation curves, lensing) that does not emit or absorb electromagnetic radiation.

Question 2

What is the defining characteristic of a Type Ia supernova that makes it useful as a standard candle?

Accepted Answer

It results from a white dwarf reaching the Chandrasekhar limit, giving uniform peak luminosity

Answer

Type Ia supernovae occur when a white dwarf reaches ~1.4 solar masses and explodes; their consistent peak luminosity allows astronomers to measure cosmic distances.

Question 3

What is the angular resolution of a telescope primarily limited by?

Accepted Answer

Diffraction due to the finite aperture of the telescope

Answer

Diffraction sets the theoretical minimum angular separation a telescope can resolve, with larger apertures producing sharper images (smaller Airy disks).

Question 4

Which phenomenon provides evidence that the universe is expanding at an accelerating rate?

Accepted Answer

Observations of distant Type Ia supernovae appearing fainter than expected

Answer

In 1998, studies of distant Type Ia supernovae found them dimmer (farther) than expected, revealing that cosmic expansion is accelerating — attributed to dark energy.

Question 5

What is the Roche limit?

Accepted Answer

The minimum distance at which tidal forces from a planet will disrupt a satellite held together by gravity alone

Answer

The Roche limit is the critical distance from a massive body inside which tidal forces overcome the self-gravity of an orbiting fluid or loosely bound satellite, tearing it apart.

ASP - Astronomical Society of the Pacific Exam Practice Test

ASP - Astronomical Society of the Pacific Exam Practice Test

ASP MCQ 5