Physics of the universe test 2

What are molecular clouds?

Large “dense” clouds, gas, and dust (Mostly hydrogen)

What Experiences “Self-gravity?”

A molecular cloud (all parts of the cloud gravitationally pulls to each other)

Gravity versus (creating) ____+____

Pressure + temperature

What is a protostar?

A star that is still in the process of forming

What raises the temperature of the star or core?

Collisions of objects

Hotter things glow what color?

Blue (Higher energy)

Cooler things glow what color?

Red (Lower energy)

Which color star would be the hottest?

Rigel

What do protostars emit?

Little wish le light and a lot of infrared light, due to their cool temps

What is accretion?

Gradual growth via gravity

What radiates (or glows0 away to keep the balance between pressure and gravity?

Energy

The star’s core temperature and density will increase until nuclear fusion and hydrogen turn into what?

Helium (H to He)

What planet is a failed star?

Jupiter

As a protostar collapses, it’s density ___ and the temperature ___, so the luminosity ___.

Increases, Increases, Increases, Increases

Young stars are surrounded by rotating disks of gas and dust, called ___.

Accretion disk

What is angular momentum?

Angular momentum is a quantity of rotational motion an object has

What is linear momentum?

An object’s mass times its velocity. measures the amount of motion in a straight line

The 4 inner planets (Mercury, Venus, earth, and Mars) are ___ planets

Terrestrial (Land) or “Rocky”

The 4 outer planets (Jupiter, Saturn, Uranus, and Neptune) are ____ planets

Gaseous “Jovian planets” or “gas Giants”

Which of the following statements is false?

All the planetesimals in our solar system have become planets

What does NEO stand for?

Near Earth Objects

What are examples of planetesimals?

All of the above

Extrasolar planets orbits __ other than our sun

Stars

What are the main methods to find exoplanets?

All of the above

What are gaps between stars called?

Interstellar

What is direct imaging?

Directly viewing a faint planet in the bright glow of its star (blocks some glow from sun) - similar to partial eclipse

What is the Doppler effect?

The motion of a light source towards or away from viewer/user

(Doppler Effect) The motion away is ____

Redshift

(Doppler Effect) The motion towards in ___

Blue shift

The smaller the wavelength the higher the ___

Frequency and Energy

What is a capital T?

A theory with a lot of evidence

Low-mass planets cannot hold on to their primary atmospheres due to their ___.

Low-gravity

Some Low-mass planets later emit gases from their interiors (via___)

Volcanoes or collect gas form comets- producing a secondary atmosphere

What is the radial velocity method?

Some stars have periodic velocity fluctuations caused by orbiting planets, and this motion is detected by Doppler shifts.

If stars spectrum is redshifted, than all the following are true except:

Star appears red

What is the transit method?

A planet passing in front of a star causes the total brightness of the star to decrease

Bigger the dip the ___ on a transit method graph

Bigger planet

Many other solar systems have ____ planets close to the star.

“Hot Jupiters”

What kind of exoplanet is easiest to detect by any of the 3 methods?

Large

Tilt of Venus if almost 180 degrees this explains what?

Why Venus spins backwards or inverse of other planets

Regions A and B of a terrestrial world are the same size. Region A has 20 impact craters and region B has 5. Which region is likely to be "older"?

Region A

What are craters?

Scars on planets’ surfaces left by impacts of large objects: asteroids and comets

When were most craters formed?

At the end of the accretion phase _the 1st billion years of the solar system)

More craters on a planets surface means that _____

The planet is older

What is radiometric dating?

Determines the age form the time the rocks were molten

What is the giant impact hypothesis for the origin of the moon?

Moon formed in a large collision between Earth and a Mars-sized protoplanet Martial ejected form the collision

What is “Maria”?

Dark regions on the moon

If an object is large enough to feel different gravitational pulls on opposing sides, it experiences ___

Tidal stress (Waves)

Seismic Waves are tested similarly to ___

Ultrasounds

Do tides also affect the SOILD part of earth?

True

What is differentiation?

Occurred and produced the different layers of Earth - dense materials sank, low density materials rose.

Which of the following layers of earth’s interior should be the hottest?

Inner Core

Which of the following layers of Earth’s interior in composed of Liquid Metal?

Outer core

Earth’s magnetic field is actually due to electric currents flowing in its conduction ___ as it rotates

Outer core

What are the only terrestrial planets with a global magnetic field?

Earth and Mercury

Which planet has no magnetic field?

Venus

Which of the following layers of the earth’s interior should be the least dense?

Crust

____ is the deformation of earths” crust, which is broken into jigsaw-like plates

Tectonism

Plate tectonics describes what?

The movement of plates (aka continental drift)

Earth has how many major plates?

7

Crustal plates are moves to be ____

Convection

Most ____ and ___ occur along plate boundaries.

Volcanoes and Earthquakes

Mars shows evidence of extensive ___ and has the biggest chasm: ___

Tectonsim and Valles Marineris

what should be true about Earth’s Internal heat?

B) It would have been greater long ago when Earth was young D) It has Radioactivity and tidal stress contributing to it

What raises the rocks temperature to the melting point with volcanoes?

Friction

Very Fluid lava creates ___

Shield Volcanoes (Hawaii Volcanoes)

Viscous or Thick Lava create ____

Composite Volcanoes (Mt. Fuji) - Looks like a pyramid

Which is Erosion?

The wearing down of a world’s surface due to mechanical action

What is the main sources of Erosion on Earth?

Wind and Water

What are some types of Erosion?

1) Wind and Water, 2) Impact Cratering - Volcanoes and tectonics plates

Without erosion, ancient features are ____

Retained

In there evidence that Mars has water?

Yes - the stream line erosion and ice pockets

The Moon and Earth are approximately the same distance from the Sun. Why does the Moon lack an atmosphere?

The Moon has weal gravity

What is considered a primary atmosphere?

includes Hydrogen and Helium (very light)

Due to ________ and _____ every terrestrial world lost its primary atmosphere they could NOT hold on to their gases

Low surface gravity (and high gas speeds)

Secondary atmospheres were acquired later due to

All of the above

Which planets basically have NO atmosphere?

Mercury and the Moon

Which planet has more volcanoes then earth?

Venus

What is the current composition of Earth mostly made form?

What is the current composition of Mars and Venus mostly made from?

Almost ALL Carson Dioxide

Mars has a much lower gravity than either Earth or Venus, Because ____

Mars in much less massive (so mass related)

Which of the following is a valid reason to build a ground-based telescope at high altitudes, like on top of a mountain?

Get above water vapor, clouds, and thick air

What decreases with altitude in the sky?

Temperature and Pressure

What is layer one of the earth’s atmosphere?

Troposphere

What is layer two of earth’s atmosphere?

Stratosphere

What is layer three of earth’s atmosphere?

Mesosphere

What is layer four of earth’s atmosphere

Thermosphere

Which larger of earths atmosphere contains the Ozone layer and eventually heats this layer up?

Stratosphere

What does the Ozone layer do?

Protects earth’s surface by absorbing UV rays

Which layer of earth’s atmosphere contains the coldest part of the atmosphere?

Mesosphere

What two things protect earth from solar wind?

The thermosphere and magnetosphere

Clouds and weather occur in which layer of the earth’s atmosphere?

Troposphere

Where does most solar wind hit the earth?

The poles

How are auroras formed?

After the magnetosphere traps charged solar wind particles, the particles collide and heat the atmosphere, causing the fluorescent glow.

What is the Hadley Circulation?

Pattern of air movement: equator to poles (vertical air convection)

What is the Coriolis effect?

The way earth’s rotation makes winds curve

What gases absorb infrared radiation, preventing the planet from cooling?

All of the Above

Why in Mars so cold compared to Venus if both of their atmospheres are made mostly of carbon dioxide, a greenhouse gas?

All of the above

This ____ is the increase in a planet’s equilibrium to a higher temperature than if there were no atmosphere

Greenhouse effect