Astronomy Exam 2

Question 1

Flux

Answer 1

Brightness

Question 2

Wavelength

Answer 2

Color

Question 3

The only directly measurable quantities in astronomy

Answer 3

Brightness, Color, Position, Time, Polarization (+ Particles)

Question 4

Kirchhoff’s Rules

Answer 4

Rules governing the emission of radiation by heated gases and solids

Question 5

Kirchhoff’s Rules #1

Answer 5

A hot, opaque gas or solid will glow with a continuous spectrum

Question 6

Kirchhoff’s Rules #2

Answer 6

A hot transparent gas emits light only at specific wavelengths that depend of the composition of the gas. This an emission line spectrum

Question 7

Kirchhoff’s Rules #3

Answer 7

A cool gas placed between the observer and a continuous spectrum source absorbs light at specific wavelengths that depend on the composition of the gas

Question 8

Spectrum

Answer 8

A representation of the amount of light something emits at each color or “wavelength”

Question 9

Light

Answer 9

Any kind of electromagnetic radiation, not just colors we can see with our eyes

Question 10

Continuum Spectrum

Answer 10

The wavelength of the peak in the continuum spectrum grows shorter (bluer) for hotter substances

Question 11

Every atom has a ________ spectrum

Answer 11

Different

Question 12

Bluer Photons

Answer 12

Higher Energies

Question 13

Redder Photons

Answer 13

Lower Energies

Question 14

When electron absorbs energy from a photon, it moves out to _____ orbital level

Answer 14

Higher

Question 15

The greatest jump means the ________ the most energy

Answer 15

absorbing

Question 16

Planet means

Answer 16

Wanderer

Question 17

Pluto was considered a planet between

Answer 17

1930-2006

Question 18

8 Planets

Answer 18

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Question 19

Definition of Planet

Answer 19

A celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and has cleared the neighborhood around its orbit.

Question 20

Definition of Dwarf Planet

Answer 20

A celestial body that is in orbit around the sun and has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape

Question 21

Solar System Properties

Answer 21

Terrestrial (rocky) is close to the sun, Jovian (gaseous) planets are farther away.

Orbits all lie in the same place, orbit in the same direction.

Most of the stuff (mass) in the sun.

Question 22

Astrometry

Answer 22

Precisely measuring the positions of the stars in the sky

Question 23

Transit

Answer 23

When one astronomical body appears to move across the face of another

Question 24

Distance to closest star (besides the Sun)

Answer 24

4.2 light-years

Question 25

Luminosity (L)

Answer 25

Total amount of power a star emits into space (does not depend on observing distance)

Question 26

Flux (F)

Answer 26

Power per unit area; measures parent brightness (does depend on distance)

Question 27

Distance (d)

Answer 27

Distance to emitting object (e.g., a star)