Lesson 1: Observing The Night Sky

Question 1

Can you explain apparent motions of objects in the night sky?

Answer 1

Our planet is tilted 23.5 degrees. The earth completes one revolution around the sun every 365.4 days. Sun is directly above the equator at the vernal equinox(March 21), above the Tropic of Cancer on the summer solstice(June 21), above the equator on the autumnal equinox(Sept 23), and above the Tropic of Capricorn on the winter solstice(Dec 21).

Question 2

Can you identify ten constellations and their bright stars?

Answer 2

Ursa Major
Ursa Minor - Polaris
Cepheus
Cassiopeia
Andromeda
Pegasus
Perseus - Algol
Lyra - Vega
Aquila - Altair
Cygnus - Deneb

Question 3

Reason for the Earth’s four seasons?

Answer 3

Earth’s axis is tilted 23.5 degrees from it’s plane of orbit around the Sun.

Question 4

Issac Newton made what discovery involving concave mirrors?

Answer 4

They cause the light rays to converge to a focus point.

Question 5

What is the optimum magnification for an eight-inch telescope?

Answer 5

(8X15) = 120x

Question 6

What are the two main types of telescopes?

Answer 6

Refracting and reflecting.

Question 7

True or False: Light changes direction when it changes mediums.

Answer 7

True

Question 8

Which if the following terms refers to how clear the sky is:
Turbulence
Fluorescence
Transparency
Seeing

Answer 8

Transparency

Question 9

Why can the Hubble Space Telescope (HST) produce better photographs than telescopes on Earth?

Answer 9

Light does not get distorted by the atmosphere.

Question 10

What is a CCD?

Answer 10

A charge-coupled device.

Question 11

Which of the following has the entire Electromagnetic Spectrum in the correct order for decreasing wavelength?:

1) violet, blue, green, yellow, orange, red
2) radio, infrared, visible light, ultraviolet, X-Ray, gamma
3) red, orange, yellow, green, blue, violet
4) gamma, X-Ray, ultraviolet, visible light, infrared, radio

Answer 11

2) radio, infrared, visible light, ultraviolet, X-Ray, gamma

Question 12

What is a photon?

Answer 12

A tiny packet or bundle if energy.

Question 13

True or False: all electromagnetic waves travel at 300,000 km/sec in a vacuum.

Answer 13

True: all electromagnetic waves travel at the speed of light in a vacuum.

Question 14

What causes electromagnetic radiation?

Answer 14

Vibrating electrons in an atom. The electrons absorb energy and jump to a higher energy level; because this is highly unstable, the electrons will release energy and revert back to the lower energy state.

Question 15

Complete the following formula: speed x time = ?

Answer 15

? = Distance

Question 16

What are the three practical units of measurement for describing the distance from Earth to Proxima Centauri (the nearest star after the Sun)?

Answer 16

The astronomical unit (AU), the light-year, and parsec.

Question 17

One parsec is equivalent to how many light-years?

Answer 17

3.26

Question 18

True or False: light leaving the earth would take little more than one second to reach the moon, 400,000 km away.

Answer 18

True

Question 19

The apparent daily motion of the Sun, Moon, and stars from east to west is caused by…?

Answer 19

Earth’s rotation.

Question 20

True or False: Reflecting telescopes often suffer from spherical aberration.

Answer 20

True

Question 21

What is a tiny bundle of electromagnetic energy called?

Answer 21

Photon

Question 22

True or False: the amount of light collected by a telescope is proportional to the area of it’s aperture(the telescope’s opening).

Answer 22

True

Question 23

How fast do radio waves travel?

Answer 23

300,000 km/s

Question 24

On March 21, the Sun is directly above which location?

Answer 24

The Equator

Question 25

True or False: the biggest telescopes in use today are refracting telescopes.

Answer 25

False: the biggest ones are reflecting telescopes.

Question 26

Who was the first person to realize that mirrors could be used to construct a telescope?

Answer 26

Issac Newton

Question 27

The distance from the earth to the Sun has been called…?

Answer 27

The astronomical unit (AU)

Question 28

What causes the earth to have seasons?

Answer 28

The tilt of Earth’s axis allows direct sunlight to hit different places throughout the year.

Question 29

True or False: The Hubble Space Telescope gives us much better images than Earth-based telescopes because it is much larger than Earth-based telescopes.

Answer 29

False: HST gives better images because light reaching it doesn’t have to travel through Earth’s atmosphere.

Question 30

Which of the following electromagnetic waves has the most energy?
Visible light
Ultraviolet
Radio waves
Infrared

Answer 30

Ultraviolet

Question 31

What is the best way to obtain astronomical data?

Answer 31

Use a telescope in space

Question 32

Two types of telescopes are…?

Answer 32

Refracting and reflecting

Question 33

True or False: all types if electromagnetic waves travel at the same speed in a vacuum.

Answer 33

True

Question 34

TRUE OR FALSE: THE NUMBER OF TIMES YOU WILL ORBIT THE SUN IN YOUR LIFETIME WILL BE THE SAME AS THE NUMBER OF DAYS IN YOUR LIFE.

Answer 34

False: as a “passenger” in Earth, you orbit the Sun in the same amount of time that the Earth does. It takes one year for Earth to orbit the Sun, so the number of times you orbit the Sun in your lifetime will be equal to the number of years in your life, not the number of days in your life.