The Solar day is longer than the sidereal day.
True. Solar day is 24hours and a sidereal day takes 3.9 more minutes.
If Earth rotated half as fast as it currently does, but its motion around the Sun stayed in same then...
The night would be twice as long
What causes the Earth's seasons?
23.5 degree tilt on Earth's rotational axis
time it takes the earth to complete one rotation as measured by the stars
time it takes the sun to go from noon one day to noon the next.
Earth travels faster than the other outer planets to Earth's periodically overtakes the other planets making it appear as though the other planets stop and move backwards.
A major flaw in Copernicus's model was that it still had
If Earth's orbit around the Sun were twice as large as it is now, the orbit would take
more than two times to traverse
distance that light travels in one year
Galileo's observation is significant because Jupiter's satellites show that...
the observation showed that bodies can orbit an object other than Earth
Modern telescopes use mirrors rather than lenses because
large lenses are more difficult to make, large lenses can be very heavy, mirrors can be computer controlled to improve resolution & light passing through lenses can be absorbed or scattered.
The MAIN reason professional observatories are built on the highest mountain tops is...
reduce atmospheric blurring
The MAIN reason that most professional research telescopes are reflectors it that...
mirrors produce sharper images that lenses do since there is no chromatic aberration
Which hero of the Renaissance postulated three "laws" of planetary motion?
Kepler's 1st law of planetary motion
1) planets orbit the Sun
2) orbits are elliptical in shape
3) orbits are noncircular
4) applies to all orbiting objects
Kepler's 2nd law
a planet moves faster when closer to its star
choose a heliocentric view over a geocentric view
1) observed the moons of Jupiter
2) observed Venus has phases
the simplest theory, is always the right answer
constructed the best geocentric model-each planet orbits Earth, and at the same time moves in circles about that orbit
farthest point from the sun
closest point from the Sun
Kepler's 3rd Law
The square of a planet's orbital period (Earth years) is proportional to the cube of its semimajor axis (AU)
Newton's First Law of Motion
An object at rest remains at rest and a moving object continues to move forever in a straight line with constant speed, uunless some external force changes their state of motion
Newton's 2nd Law
Acceleration of an object os directly proportional to the net applied force and inversely proportional to the object's mass
Newton's 3rd Law of Motion
To every action there is an equal and opposite reaction
Let's say Earth has the same mass, but is half the radius. How does the force of gravity change?
Half the radius then, for the same mass means four times the gravity. The gravitational force is inversely proportional to the square of the distance
You throw a baseball to someone; before the ball is caught, it is temporarily in orbit around Earth's center?
The leading theory of solar system formation is...
The planets formed from the same flattened, swirling gas cloud that formed the Sun.
What is the number of confirmed planets beyond our solar system?
more than 300
Terrestrial planets (earth-like)
Mercury, Venus, Earth and Mars
Most asteroids are found
between Mars and Jupiter
The planet with the largest diameter in our solar system is
The overall shape of the orbits of most the planets
is slightly elliptical, but nearly circular
Sunlight absorbed by Earth's surface is re-emitted in the form of
If Earth has no moon, then tides would
occur with the same frequency, but would not be as strong. The Sun also affects the tide but lesser than the moon.
The most likely theory of the formation of the moon is...
formed from a collision of Earth with a Mars-sized object
The region around Earth where the magnetic field traps charged particles is the...
Van allen radiation belts
Which of these gases is least abundant in our atmosphere?
Terrestrial planets have one or no moon.
The Jovian planets have large number of moons.
Jovian planets share
1) many moons
2) large magnetic fields
3) lots of hydrogen &helium gas
4) differential rotation
5) have much thicker
Mercury's solar day is longer than its solar year
Feature of Venus?
that the temperature on the surface does not change significantly between day and night
Jupiter's bright zones are cloud streams made of ___________ ice crystals.
Venus's surface is permanently obscured by clouds. So it has been mostly studied by...
orbiting satellits using radar
Jupiter has a large magnetosphere and strong magnetic field
The vastly different atmospheric character of Mars is likely due to...
a reverse greenhouse effect
The most famous and long lasting storm in the solar system is Jupiter's
Jupiter's atmosphere is mostly
What effect does the greenhouse effect have on the surface environment of Venus?
to raise the surface temperature by hundreds of degrees
From Earth Venus is the brightest then Jupiter
A feature of MArs which distinguishes it from the other planets is
the dust storms
Why did the Soviet spacecraft survive for only a few minutes on the Venusian surface?
The conditions of extreme pressure, corrosive atmosphere, and high temperatures severely damage it.
The most likely explanation for the retrograde rotation of Venus is...
impact of a massive object on it early in its history
Both Jupiter and Saturn
1) emit more energy than they absorb from the Sun
2) have liquid metallic hydrogen in their interiors
3) rotate very rapidly than the terestial planets
4) have rings
The seasons on Uranus: Its strange tilt produces extreme seasonal variations
Saturn is the least dense of the planets, and could float on water
Neptune has the Great _____ spot
Saturn's rings exist because they lie within the plane†'s Roche limit
Triton's orbit is unusual because it is retrograde
Io's surface appears very smooth bc...
is continuously by volcanic activity
The Galilean moons of Jupiter are sometimes described as a miniature inner solar system bc...
the moon's densities decreases with increasing distance from Jupiter
What future awaits Triton, the largest satellite of Neptune?
tidal breakup as it spirals closer to Neptune
What is the Dynamo theory?
The magnetic field of Earth is caused by the spinning electrically conductive metal core of the planet
Uranus and Neptune magnetic fields are offset from the planet's centers
The formaton of Jupiter and its moons may have mimicked on a small scale the formation of the Sun and the interior planets
Jupiter's moon's unique qualities.
Titan= has nitrogen atmosphere like earth's early atmosphere
Io= has volcanic activity
Europa= appear to have water
Triton= completely doomed, within roche limit of Neptune
Reading Music Is Very Unsatisfying for Xylophones and Glockenspiels
Radio, Microwave, Infrared, Visible, Ultraviolet, X-Ray and Gammaray
absolute temperature cannot be negative (-30K)
the lower the temperature the longer the wavelength. higher the temperature the shorter the wavelength.
What is the most abundant element in the Sun?
Compared with Earth's diameter, the Sun's diameter is about...
100 times larger
What is the primary source of the Sun's energy?
fusion of light nuclei to make heavier ones
The density of the Sun is most similar to that of??
The proton-proton cycle involves what kind of fusion process?
hydrogen into helium
How long does it take for a photon to escape from the solar core?
about a million years
how much mass will the sun lose to space during its lifetime, through the solar wind?
a few thousandths of its total mass
What is a neutrino
an elusive, subatomic particle having little mass, difficult to detect.
To determine the radius of a star, you must know what?
luminosity and temperature
The mass of a star may be determined
by studying its orbit around a binary companion
how hot is the core of the sun?
What is luminosity?
the amount of radiation (energy) leaving a star per unit of time.
What's a Giant?
starts with radii between 10-100 times that of our sun
What's a dwarf?
anything smaller in radius than our sun
What is the single most important characteristic determining the course of a star's evolution?
Why is dust important to solar system formation?
1) it radiated in the infr-red which helps to cool the cloud down
2) it provides a platform on which additional material can "climp" up
The Earth has a solid, dense, nickle-iron core
The temperature at the center of Earth is approx the same as the surface of the sun
Seismis waves are how we learned about the Earth's structure
Concerning the Earth's greenhouse effects...
The concentration of CO2 in the atmosphere has been increasing since the start of the industrial revolution
Which of these is the smallest of the terrestrial world?
Mercury has the largest eccentricity of the Terrestial worlds
Mercury has the largest angle to the plane of the rest of the solar system
The atmosphere of Mars..
mostly nitrogen like Venus and much less dense than Earth's
What is absolute zero?
The temperature at which all thermal motion stops
Magnitude for the temperature for the center of the sun
The Radiation zone is...
A region of the sun where the material is mainly ionized.
A region where photons can travel through relatively freely
As few as two wavelength measurements can be used to estimate the temperature of a star.
What is plotted on the HR diagram?
Luminosity and Temperature
As the distance of an object increases the parallax decreases
are larger and cooler than our sun
What is the ultimate stage of our star
to become a black dwarf
Galaxies merging causes
star formation and destruction of spiral arms
why do typw 1 supernovae provide signposts for large distances?
they all have the same absolute luminosities
relates galatic recession velocity to the distance to the galaxy in question
What is driving the expansion of the universe?
Nuclear fusion in the core of a massive star cannot create elements much heavier than iron.
This is true.
The Sun will get brighter as it begins to run ot of hydrogen (fuel) in its core
White dwarf is supported by the pressure of tightly packed- electrons
All things , included light are attracted by gravity
What is general relativity?
The warping of space, or curving by matter.
The lighthouse model explains how...
a rotating neutron star generates an observable beam of light
most pulsars are observed as radio sources
What is the event horizon of a black hole?
"surface" from inside of which nothing can escape
As a spaceship's velocity gets closer to the speed of light
its length will decrease and its clock will run more slowly
Due to the density and collisions among galaxies, ___________ are rare in the centers of clusters.
Where is dark matter located?
dark matter appears to be concentrated in spherical haloes around galaxies but extends far beyond the visible matter
the diamete of the Milky Way is