Eps Sci 9 Final

The Hubble constant is the slope of the line on a graph of galactic_____.

velocity versus distance (v/d)

The Hubble constant has units of ______.

1/time (s^-1 or 1/s)

The Hubble constant tells us that_____.

The universe is 13 billion years old

The solar system is _____ years old.

4.5 billion

The Hubble constant also tells us that _____.

The universe is expanding uniformly

The main asteroid belt lies between the planets ______.

Jupiter and Mars

204Pb and 206Pb are examples of different _____ of the element lead.

isotopes

One astronomical unit is defined as ______.

One earth-sun distance

Asteroids of the asteroid belt are _______.

planetesimals broken and reassembled by multiple collisions

The primary heat source responsible for melting planetesimals was _______.

26Al radioactive decay

The Titus-Bode law describes______.

the spacing of planets around our sun

Looking down on the Earth from the north pole, the planets of our solar system generally rotate____.

counterclockwise

Only ____ have retrograde rotation.

Venus, Uranus, and Pluto

The inner planets are made primarily of_____.

rock

the outer planets are primarily made of____.

gas

The protoplanetary disk that made the solar system was a disk because____.

a balance between gravitational force and centripetal force acting on particles near the growing sun

most of the angular momentum of our solar system is in

the planets

The main source of heat in the protoplanetary disk is

viscosity in the disk

most meteorites in our possession today are

stone

chondrites are

undifferentiated

one of the best places to find meteorites

Antarctica

the first person to establish the age of earth and the solar system was

Clair Patterson

The earth and solar system were first dated using____.

238U and 235U to form 206Pb and 207Pb

Half life is

the time it takes for a radioactive nuclide to form in a star

the concept of epicycles was put forward by

Ptolemy

epicycles explained

retrograde motions of planets

_______ asserted that earth rotated on its own axis once daily and traveled around the sun once yearly

Copernicus

_____is credited with first suggesting that planets move in elliptical orbits with the sun as one of the foci, and planet sweeps out equal areas in equal times

Kepler

Newton's law of gravitation

F= G (m1m2)/r^3

Jupiter's hill sphere explains

the position of the outer edge of the asteroid belt

The concept of resonance explains

gaps in the asteroid belt

the first asteroid to be discovered was

1 Ceres

the largest of the asteroids in the asteroid belt is____

Ceres

The Kuiper belt is _______

composed of asteroids and comets beyond the orbit of Neptune

The Oort cloud is _______

a spherical region surrounding the solar system from which long-period comets derive

Pluto is an example of

a member of the Kuiper belt

The moon formed as a result of_____

a massive collision between early earth and another planetary body

Maria (plural for Mare) on the moon are made of _____

basalt

Highlands on the moon are made of

anorthosite

The moon has a ____ spin:orbit resonance with Earth

1:1

the sun appears _____ times larger in the sky from Mercury than it does from Earth

3

MERCURY

diameter = 4,879.4 km (slightly larger than the moon)
volume = 0.054
mass = 0.055
density = 5430 kg/m^3
surface gravity = 0.376
rotation period = 58.65 earth days
revolution period = 87.97 earth days
mean surface T = 166.96 C (332 F)
magnetic field = 1% earth (partly liquid core)
core is partly molten
core is 75% of the diameter of the planet

Mercury has a magnetic field because______

it has a partially molten core...but vexing - rotation is too slow

Caloris

fluid erupted lavas, huge basin on Mercury

Messenger

MErcury Surface, Space ENvironment, GEochemistry, and Ranging

-orbited Mercury between 2011 and 2015, launched in 2004
-studied surface geology, chemical composition, and magnetic field

The density of Mercury is extremely_____Mercury

high. (5400 kg/m^3)

Mercury surface is dominated by ______

impact craters

________not as important as on Moon.Volcanism

Volcanism (no maria)

Techtonism produced large_______.

scarps (shrinkage cracks)

_______temperatures in solar system

most extreme

day side

425º C (800º F)

night side

-210º C (-350º F)

2nd most _____ orbit in the solar system (next to Pluto)

eccentric

spin:orbit resonance

3:2

rotates ___ times every orbit

1.5

orbital period

88 earth days

spin period

59 earth days

If you were on Mercury, the sun would pass overhead ____ every _____ orbits around the sun, or every ____ earth days

once; two; 176

One day on Mercury takes ______ Mercury years

two

Calories basin

one of the solar system's largest impact structure (1550km, 960 miles in diameter)
-infilled with lava
-impactor was 60 miles (100 km) in diameter
-about the same age as Mare Ibrium or Mare Orientale on the moon

antipode

"weird terrain"
-causes surface disruption of the pressure waves that come from the Caloris impact at the antipode

Gravity is ____ at the Caloris basin

high

Calories basin contains the ______

dense impactor
-the sun attracts this dense side of Mercury

Mercury sidereal day

time to rotate once on its axis

Density arguments indicate that Mercury has ______

a much larger iron-rich core than Earth (relative) and moon

Range in topography is _____ by comparison with moon or mars

small

surface is generally _____ than the lunar highlands

younger

Mercurian interior was ______ for _____

hotter ; longer

Renoir basin

a peak ring basin featuring 100km- wide ring of massifs in the center of the crater

once; two; 176

One day on Mercury takes ______ Mercury years

two

Caloris basin

one of the solar system's largest impact structure (1550km, 960 miles in diameter)

-infilled with lava

-impactor was 60 miles (100 km) in diameter

-about the same age as Mare Ibrium or Mare Orientale on the moon

antipode

"weird terrain"

-causes surface disruption of the pressure waves that come from the Caloris impact at the antipode

Gravity is ____ at the Caloris basin

high

Calories basin contains the ______

dense impactor

-the sun attracts this dense side of Mercury

Mercury sidereal day

time to rotate once on its axis

Density arguments indicate that Mercury has ______

a much larger iron-rich core than Earth (relative) and moon

Range in topography is _____ by comparison with moon or mars

small

surface is generally _____ than the lunar highlands

younger

Mercurian interior was ______ for _____

hotter ; longer

Renoir basin

a peak ring basin featuring 100km-wide ring of massifs in the center of the crater

This morphology is found in craters ______ than central peak craters

larger

They are probably related to the _____

formation of central peak craters, although the reason for the more complex morphology is uncertain

What is the Renoir basin

ring-in-ring indicates larger impact than complex craters
-bowl-shaped crater 20km in diameter

Tir planitia

discovery rupes

prominent typographic scarp 2km high and 650km long

-fault scarp cutting old craters, shortens craters showing that the forces are compressive

Mercury appears to have grown ________ in its history due to global cooling

smaller

Mercury _____ as it cooled

shrank

dark material ejected from craters looks to be _____

carbon

-dark

-inefficient at absorbing neutrons

Carbon is excluded from metal cores containing significant ______

S or Si