Astronomy-2

Question 1

Apparent Magnitude

Answer 1

How bright objects appear from earth

Question 2

Absolute magnitude

Answer 2

How bright an object appears from a distance of 10 parsecs

Question 3

Stellar Parallax

Answer 3

The apparent shift of position if a nearby star (or other object) against the background of distant objects

Question 4

Parsec

Answer 4

The distance from which one astronomical unit (AU) sub tends an angle of 1 arc sec

Question 5

Black body radiation

Answer 5

A hypothetical object which is a perfect absorber and perfect emitter of radiation over all wavelengths

Question 6

Line emission spectrum

Answer 6

This emission occurs when an atom, element or molecule in an excited state returns to a configuration of lower energy at specific wavelengths of radiation

Question 7

Absorption spectrum

Answer 7

A spectrum of EM radiation transmitted through a substance showing dark lines or bands due to absorption at specific wavelengths

Question 8

Flux

Answer 8

Power per unit area

Question 9

Peak wavelength

Answer 9

The wavelength where the spect ru m reaches its highest intensity

Question 10

Radiation pressure

Answer 10

The outwards pressure in main sequence stars due to radiation from fusion in the core

Question 11

Nuclear Fusion

Answer 11

This is when two small light nuclei join together to make one heavy nucleus