2.1/2.3 Practice

Question 1

When the Sun became a star, it blew out the lighter elements and gases to form the

Accepted Answer

Oort Cloud., Kuiper Belt.

Question 2

Why do most astronomers think the condensation theory of solar system formation is correct?

Accepted Answer

various stages of solar system formation have been observed, the star system Beta Pictoris is an example

Question 3

So far there has been six _____ planets that have been discovered - including Pluto & beyond.

Accepted Answer

dwarf

Question 4

Which statement best describes the terrestrial planets?

Accepted Answer

no or very few moons; solid surfaces; moderate atmospheres

Question 5

The fact that all of the planets orbit in the same direction as the Sun rotates indicates that

Accepted Answer

they all formed at about the same time & relative space.

Question 6

The planet Mercury is the densest of all the planets - this means that

Accepted Answer

it has more material compacted together.

Question 7

Exoplanet evolution can also be explained using comparative planetology.

Accepted Answer

TRUE

Question 8

The Kepler spacecraft has discovered _____ of extrasolar planets (so far).

Accepted Answer

thousands

Question 9

Astronomers use _____ of the origin of the solar system based on current observations.

Accepted Answer

models

Question 10

Why do terrestrial planets have high densities and solid surfaces?

Accepted Answer

lighter elements were stripped away by the Sun

Question 11

All planets in our solar system orbit _____ around the Sun - as seen from the north pole.

Accepted Answer

counterclockwise

Question 12

According to the condensation theory, the Sun formed at the center of a nebula cloud with

Accepted Answer

the planets, asteroids, comets etc. forming as leftovers.

Question 13

Except for a slight off-set of the planet _____ - all planets orbit in the same plane.

Accepted Answer

Mercury

Question 14

What is the major difference between terrestrial planets and Jovian planets?

Accepted Answer

terrestrial planets are smaller and have solid surfaces

Question 15

How did the Sun form from a nebula cloud (according to the condensation theory)?

Accepted Answer

matter built up and became hotter & hotter at the center, gravity collapsed the cloud slowly at first & then rapidly

Question 16

Our solar system (so far) is pretty much the same as others in the galaxy.

Accepted Answer

FALSE

Question 17

The Oort cloud is an immense spherical cloud with over 6 trillion icy objects extending

Accepted Answer

about two-thirds of the way to the next nearest star system., approximately 3 light years outward from the Sun.

Question 18

Beta Pictoris is a "new" star system (20 million years old) and has recently been found to

Accepted Answer

have a planet orbiting it.

Question 19

KBO's - or Kuiper Belt Objects - exist beyond the orbit of Neptune and contains

Accepted Answer

many minor & dwarf planets like Pluto, Eris & Sedna.

Question 20

Which statement best describes Jovian or gas giant planets?

Accepted Answer

many moons; thick atmospheres; rapid spin rates

Question 21

Our solar system with 8 known major planets, asteroids & comets may or may not be

Accepted Answer

unique.

Question 22

Asteroids are small rocky/metallic leftovers from the

Accepted Answer

beginning of the solar system.

Question 23

There are _____ major planets in our solar system.

Accepted Answer

eight

Question 24

Comets can best be described as

Accepted Answer

dirty snowballs with highly elongated orbits.

Question 25

Our solar system also includes one ______ and countless asteroids & comets.

Accepted Answer

sun, star

Question 26

Many small, moon-like bodies collided to form the inner planets. They are known as _____.

Accepted Answer

planetesimals

Question 27

Where is the asteroid belt located?

Accepted Answer

mostly between the orbit of Mars & Jupiter

Question 28

Which statement best describes a dwarf planet?

Accepted Answer

object that is round but has not cleared its orbital debris

Question 29

Asteroids are also known as

Accepted Answer

"minor planets."

Question 30

The Jovian planets (gas giants) have the most

Accepted Answer

moons.

Question 31

Comparative planetology compares and contrasts properties of worlds to see how they evolved.

Accepted Answer

TRUE

Question 32

In order from the Sun: Mercury, Venus, Mars, Earth, Jupiter, Saturn, Uranus & Neptune.

Accepted Answer

FALSE

Question 33

The condensation theory & the solar nebula theory adequately explains today's solar system.

Accepted Answer

FALSE

Question 34

Why do Jovian planets have relatively low densities?

Accepted Answer

they formed farther from the Sun & kept lighter elements

Question 35

Definition of a planet includes that it orbits the Sun, is not a satellite, is round and

Accepted Answer

has cleared its orbit of debris.

Question 36

Which statement best describes the definition of a moon?

Accepted Answer

a natural satellite orbiting a larger body

Question 37

Each planet’s distance is roughly twice that as its next inward neighbor.

Accepted Answer

TRUE

Question 38

In our solar system, all major planets lie (roughly) in the same ____ & orbit in the same ____.

Accepted Answer

plane, direction

Question 39

A ____ is a cloud of gas & dust that has contracted under gravity to form a star & planets.

Accepted Answer

solar nebula

Question 40

In science, all _____ can change or become modified with new discoveries.

Accepted Answer

theories

2.1/2.3 Practice

Questions 40

2.1/2.3 Practice

Questions 40