Astronomy 109 Lab 1-5 Midterm Fall 2022

Question 1

Scientific Notation: when the decimal is moved to the left the exponent is?

Answer 1

positive or +

Question 2

Scientific Notation: when the decimal is moved to the right the exponent is?

Answer 2

negative or -

Question 3

Scientific Notation: what is a million and prefix?

Answer 3

10^6, mega

Question 4

Scientific Notation: what is a billion and prefix?

Answer 4

10^9, giga

Question 5

Scientific Notation: what is a trillion and prefix?

Answer 5

10^12, tetra

Question 6

Scientific Notation: what is a millionth and prefix?

Answer 6

10^-6, micro

Question 7

Scientific Notation: what is a billionth and prefix?

Answer 7

10^-9, nano

Question 8

Scientific Notation: what is a trillionth and prefix?

Answer 8

10^-12, pico

Question 9

What is one degree equal in arcminutes?

Answer 9

60’ arcminutes

Question 10

What is 1’ or 1 arcminute?

Answer 10

60” arcseconds

Question 11

Astronomical Unit ( AU):

Answer 11

-used to express the average distance between earth and sun
- distance between earth and sun= 1 AU

Question 12

What is 1 AU in miles and kilometers?

Answer 12

• kilometers:1.49x10^8
  -miles: 9.29x10^7

Question 13

Light year (ly):

Answer 13

the distance that light travels in a year, used to expressed distances of nearby stars

Question 14

Celestial Sphere:

Answer 14

dome in which we see the sky

Question 15

Declination ( DEC):

Answer 15

the angular distance of how high or low something is to the equator, analogous to latitude

Question 16

Right ascension ( RA):

Answer 16

measured along the eastward equator, measured in time, ranges from zero point to vernal equinox

Question 17

What is the equatorial co-coordinate system?

Answer 17

right ascension and declination

Question 18

Parts of the celestial sphere
- Horizon:

Answer 18

the apparent line that separates earth from the sky

Question 19

Parts of the celestial sphere
-Zenith:

Answer 19

the point directly overhead on the celestial sphere

Question 20

Parts of the celestial sphere
-Meridian:

Answer 20

is the great circle passing through the zenith, due north and south points on the observers horizon, a star reaches its maximum height above the horizon when its on the median

Question 21

Parts of the celestial sphere
- celestial poles:

Answer 21

the projection of the earths poles onto the celestial sphere

Question 22

Parts of the celestial sphere
- celestial equator:

Answer 22

an extension of the earths equator onto the celestial sphere

Question 23

Azimuth:

Answer 23

the angle measured eastward from the true north to the point of the horizon below the star and ranges from 0 degrees to 300 degrees

Question 24

Altitude:

Answer 24

• how far above the horizon an object is seen in the sky
• altitude of Polaris = observers latitude ( in northern hemisphere )

Question 25

What is Horizon Co-ordinate System?

Answer 25

Altitude and Azimuth

Question 26

Constellation:

Answer 26

-pattern/groupings of stars named after mythological animals, “characters” or objects -examples: Andromeda, Perseus, Crux, Orion

Question 27

Asterisms:

Answer 27

-Asterisms are the shapes within the constellations, sometimes patterns are also formed by stars in different constellations. -example: The Big Dipper in the constellation Ursa Major, Summer Triangle, Winter Triangle

Question 28

Never-Set Stars:

Answer 28

DEC > 90 – LAT

Question 29

Never-Rise Stars:

Answer 29

DEC < -90 + LAT

Question 30

Rising/Setting Stars:

Answer 30

DEC < 90 – LAT and DEC > -90+ LAT

Question 31

What is the importance of Polaris: the pole star?

Answer 31

1. Polaris indicates the direction of true north as it sits on the NCP 2. Altitude of Polaris = Observer’s Latitude (In Northern Hemisphere)

Question 32

Parallax:

Answer 32

is the apparent shift in position of an object when the observer views it from two different lines of sight

Question 33

distance:

Answer 33

r to a celestial object

Question 34

Finding the distance: r to a celestial object using the small angle formula:

Answer 34

Small-Angle Formula: r=(206265")(d) divided by (a)

Question 35

what does d represent in the small angle formula for finding distance?

Answer 35

where d is the separation between two perspectives

Question 36

what does a represent in the small angle formula for finding distance?

Answer 36

𝛼 is the parallax angle in arcseconds

Question 37

true or false: do you have to convert a into arcseconds in small angle formula for finding distance?

Answer 37

true

Question 38

Finding the diameter: formula for celestial objects using the small angle formula

Answer 38

𝒅= (r)(a) divided by (206265")

Question 39

what does r represent in the small angle formula for finding diameter?

Answer 39

where r is the distance to the celestial object

Question 40

what does a represent in the small angle formula for finding diameter?

Answer 40

𝛼 is the angular diameter of the object in arcseconds.

Question 41

true or false: do you have to convert a into arcseconds in the small angle formula for finding diameter?

Answer 41

true

Question 42

what is the formula for finding the mass of Jupiter?

Answer 42

Mjupiter=(4)(pi^2)(d)^3 divided by (G)(P)^2

Question 43

what does P stand for in the formula for finding the mass of Jupiter?

Answer 43

-(seconds)^2 - is the orbital period of the moon in units of seconds

Question 44

what does D stand for in the formula for finding the mass of Jupiter?

Answer 44

-(meters)^3 - orbital size/distance of the Jupiter’s moon in units of meters

Question 45

what does G represent in the formula for finding the mass of Jupiter?

Answer 45

-G is the gravitational constant - 6.673x10^-11 m^3/kg/s^2

Question 46

what is the formula for finding the volume of celestial objects?

Answer 46

V=(4/3)(pi)(R)^3

Question 47

what does r represent in the formula for finding volume of celestial objects?

Answer 47

where R is the radius of the object in meters

Question 48

what star is in the summer triangle?

Answer 48

vega

Question 49

what star is in the winter triangle?

Answer 49

Sirius