study guides

Question 1

Star

Answer 1

a large, glowing ball of gas that generates heat, and light through nuclear fusion reactions in its core. (Sun)

Question 2

Planet

Answer 2

moderately large object that orbits a star, shines reflected light. (Earth)

Question 3

Moon

Answer 3

orbits a planet. (moon)

Question 4

Comet

Answer 4

relatively small, icy object that orbits, and develops tails as it approaches the star.

Question 5

Asteroid

Answer 5

small, rocky object that orbits a star. (mathilde)

Question 6

Solar System

Answer 6

the sun, and all material that orbits; planets, satellites, asteroids, comets.

Question 7

Exoplanetary System

Answer 7

any system of planets beyond our solar system. (trappist 1 system)

Question 8

Galaxy

Answer 8

collection of billions of stars held together by gravity, orbiting a common star.

Question 9

Local Group

Answer 9

smaller collections of galaxies (50+)

Question 10

Galaxy cluster

Answer 10

bigger collections of galaxies (1500+)

Question 11

Supercluster

Answer 11

collections of groups and clusters.

Question 12

Galaxy Filament

Answer 12

collection of superclusters

Question 13

how many stars in in our galaxy?

Answer 13

100 billion

Question 14

Practice writing small and big numbers in scientific notation.

Answer 14

Bigger than zero numbers- move to the left

93 . 000000 = 9 . 3000000 (less than 10) 9 . 3 * 10^7

Less than zero numbers- move to the right

0 . 0004 = 4 . 0 x 10^-4

Question 15

million(th)
billion(th)
trillion(th)

Answer 15

million 10^6 (-6)
billion 10^9 (-9)
trillion 10^12 (-12)

Question 16

multiplying and dividing exponents

Answer 16

multiplying= adding exponents
dividing= subtracting exponents

Question 17

Astronomical unit

Answer 17

( AU ) average distance between the earth and sun (1 AU)
1 AU = 93 million miles

Question 18

Lightyear

Answer 18

distance light travels in one year

500 light years = 500 years

Half of it’s value = traveling slower = doubled

Question 19

how old is our universe

Answer 19

13.7 billion years

Question 20

How many stars are present in the observable universe?

Answer 20

100 billion galaxies
100 billion stars per galaxy

100 billion * 100 billion

10^2 * 10^2 * 10^18 = 10^22 stars

Question 21

horizon

Answer 21

where the sky and land meet

Question 22

celestial sphere

Answer 22

a model used by astronomers to understand the night sky. locates stars, galaxies, and plots the courses of the sun, moon, and planets

Question 23

meridian

Answer 23

line passing through the zenith, connecting the north and south points

Question 24

zenith

Answer 24

directly overhead

Question 25

altitude

Answer 25

height of an object

Question 26

azimuth

Answer 26

width of an object

Question 27

june 21st

Answer 27

summer solstice

Question 28

march 21st

Answer 28

spring equinox

Question 29

september 21st

Answer 29

fall equinox

Question 30

december 21st

Answer 30

winter solstice