Solar System Final (Mercury, Venus, Mars, Asteroids, Jupiter & Saturn, Uranus & Neptune, Comets, Exoplanets, Earth's Moon, Earth as a Terrestrial Planet, The Origin of the Solar System)

(Unit 34 - Structure of the Solar System) How can we determine the density of a distant planet?

Outer planets, indicate that they contain mainly low-density material in their interiors...

Kuiper Belt

a region containing many large icy bodies and from which some comets come. The region appears to extend from the orbit of Neptune at about 30 AU, past Pluto, out to approximately 55 AU.

Jupiter and Saturn

aurora: the light emitted by atoms and molecules in the upper atmosphere. This light is a result of magnetic disturbances caused by the solar wind and appears to us as the Northern or Southern Lights belt: a dark, low-pressure region in the atmosphere of the Jovian planet, where gas flows downward Great red Spot: a reddish elliptical spot about 40,000 km by 15,000 km in size in the Southern Hemisphere of the atmosphere of Jupiter. The Red Spot has existed for over three centuries (45.3) Liquid metallic hydrogen: a form of hot, highly compressed Hydrogen that is a good electrical conductor, found in the interiors of Jupiter & Saturn. Vortex: a strong spinning flow within a gas or liquid, such as the Great Spot on Jupiter (45.3) Zone: a bright, high-pressure region in the atmosphere of a Jovian planet, where gas flows upward Jupiter shows more prominent bands than Saturn is that .....Saturn is farther from the Sun. It is cooler, so different chemicals are able to condense in the high atmosphere, creating a haze (Reason: The difference is a layer of ammonia haze (crystals form like tiny snowflakes of ammonia). Its too warm for one to form at the top of Jupiter's atmosphere.) Jupiter and Saturn generate substantial internal heat because They emit more infrared radiation than is expected to result from solar heating alone Inside Jupiter and Saturn, extreme pressure creates a layer of highly compressed., metallic hydrogen. List each layer and its properties: · It plays a role in creating the planet's magnetic field (Reason: The size of the layer is why Jupiter's field is incredibly strong compared to Earth's.) · It is a liquid. · Electric currents can flow in it. JUPITER & SATURN'S ATMOSPHERE: -Jupiter and Saturn have atmospheres composed mainly of hydrogen and helium (Jupiter and Saturn are similar in composition to the Sun.) -Metallic liquid hydrogen, formed at tens of millions of times normal atmospheric pressure, acts like a metal. Consequently,currents can flow through it. -If you attempted to land on a Jovian planet, your ship would descend into the gaseous layers until it was crushed and/or melted by pressure and heat FEATURES OF JUPITER: four bright moons, orange & brown banding, and red spot upiter and Saturn have rapid jet streams that alternate directions of flow. Arrange the arguments into a logical explanation of how the jet streams are created in Jupiter's northern hemisphere. 1. Heat from the interior warms gases low in the atmosphere 2. Hot material rises 3. At the surface, rising materials spreads out in all directions 4. The Coriolis effects deflects material moving toward the pile to the east and material moving toward the equator to the west. 5. This result in an eastward flow on the north side and a westward flow on the south, creating opposite streams. type of activity matched w description on Jupiter and Saturn.· 300+ year old storm — Great Red Spot on Jupiter · Ring of light emitted near the poles — Aurora · Intermittent flashes of light — Lightning · White oval regions between bands — Temporary storms · Whirling zone between jet streams — Vortex false, Radio data from the Juno mission to Jupiter showed that the Great Red Spot is about 100 km deep. Reason: Actually, Juno's data showed the spot is almost twice that, extending 200 km down. · How do we know that Jupiter and Saturn generate substantial internal heat? They emit more infrared radiation than is expected to result from solar heating alone. Match the probe to the planet it explored. · Juno — Jupiter · Cassini — Saturn · New Horizons — Pluto · Voyager 2— Jupiter, Saturn, Uranus & Neptune ·Jupiter and Saturn show circles of light near their poles. What causes these? Charged particles from the solar wind channeled into the upper atmosphere · Charged particles from some of the moons and rings hitting the upper atmosphere Jupiter's magnetic field is 20,000 times stronger than the Earth's, and Saturn's is 500 times stronger than Earth's. What best explains this difference between the gas giants and Earth? Magnetic dynamo currents can flow in the layers of liquid metallic hydrogen in the giants. The layer is bigger in Jupiter than Saturn. Auroras occur when charged particles funneled by a planet's magnetic field collide with the planet's atmosphere

(Inner Planets: Unit 40- Mercury) What is the evidence for a large iron core in Mercury? What might explain why it so large?

- Once had a thicker rocky crust that blasted off by the impact of a large planetismal early in the Solar System history. -its density

(Unit 1 - Our Planetary Neighborhood) About how many times bigger in radius is the Sun than Earth? How many times bigger in mass?

- The Sun is 100 times the diameter of Earth and over 300,000 times more massive.

(Unit 35 - The Origin of the Solar System) How are radioactive elements in rocks used to estimate the age of the Solar System? Why do rocks have different ages?

- due to radioactive atoms. -radioactive atoms w different half-lives

(Inner Planets: Unit 43- Asteroids) How have differentiation and impacts led to the variety of asteroid types we observe today?

--—Iron meteorites exists (Reason: Yes. The source of iron meteorites is believed to be the iron core of differentiated asteroids that were subsequently broken up into pieces)

(Inner Planets: Unit 40- Mercury) What are scarps? How might they have formed?

-A cliff produced by vertical movement of a section of the crust of a planet satellite (40.1) -Because the scarps cut across many impact craters, they must have formed later in Mercury's history when the planet cooled and shrank, wrinkling like a dried apple.

(Unit 35 - The Origin of the Solar System) What is the difference between condensation & accretion? What are planetesimals?

-Accretion is the addition of matter to a body. Examples are gas falling onto a star and asteroids colliding and sticking together. Whereas condensation is conversion of free gas atoms or molecules into a liquid or solid. A snowflake forms in our atmosphere when water vapor condenses into ice. -Planetesimals one of the numerous small, solid bodies that, when gathered together by gravity, form a planet.

(Inner Planets: Unit 42- Mars) What are the major geological features on Mars?

-All the features that are evidence of past geologic activity on Mars... Giant volcanic mountains such as Olympus Mons · Giant rifts such as the Valles Marineris -Mars has huge volcanoes and a long chasm that may have...Opened up as the result of internal tectonic or geological activity. -Water-ice is present under the surface in...Many regions and is kilometers thick at the poles

(Inner Planets: Unit 41- Venus) What gas dominates Venus's atmosphere? How is this known?

-CO2 - astronomers know the atmospheric composition of Venus from its spectrum and from measurements w space probes

Mercury

-Carol Basin: ---The largest impact crater region yet seen on Mercury. ---The Basin is a huge impact feature that is somewhat like a.... Lunar mare. ----Its circular shape and the presence of odd terrain on the opposite side of the planet from it indicates that the Basin on Mercury was likely caused by... A massive impact (Reason: The circular shape indicates the impact, and the global effect shows is was massive). Perihelion: the point in a planet's orbit where it is closest to the Sun. -Scarp: ---A cliff produced by vertical movement of a section of the crust of a planet or satellite ---Scarps in Mercury's crust suggest that... core has shrunk as it has cooled ---Scarps are one kind of wrinkle -If comets carrying enough water to create an ocean collided with Mercury, what do you suppose would happen? They would turn into ice by either the water trucking mercury's surface and vaporizing, drifting toward Mercury's cold polar regions and freeze or would -Though Mercury's escape velocity is almost twice as much as the Moon's, Mercury's closeness to the Sun makes its temperature higher, causing any gas molecules to readily escape into space. -How would a Mercury-mass planet at Earth's distance from the Sun, be different from Mercury? Would have crustal plate tectonics because of internal heat and having enough of it, which Mercury does not have. -MERCURY"S VOLCANIC ACTIVITY: ---Mercury has had more volcanic activity than the Moon. ---Mercury has more volcanic activity than the Moon due to... it's magnetic field and rotational wobble implying the interior is still molten. ---Astronomers believe pits or hollows on Mercury's surface is due to volcanic activity or volcanic venting, which might have been indirectly caused by impacts altering the crust -MERCURY"S SURFACE: ---Mercury's surface resembles the Moon in being... heavily cratered, having large ancient lava flows, and lacking an atmosphere. ---Mercury's surface experiences extremes of hot and cold because... It is so close to the Sun and has such a long night ---Surface features: Craters,(Solidified) Lava floods, Scarps, Volcanic vents, Surface stretching & wrinkling -On Mercury's surface... Large impact crater occurred first, then lava flow, and then small crater -Where did the ice seen on Mercury come from? Comets carrying water that struck the surface and vaporized, would try to escape to space, but would be slowed down by Mercury's gravity; Which then may result in the vapor drifting toward Mercury's cold polar regions and cause them to freeze. Or, from volcanic outgassing where gases are released which includes water vapor, and water vapor is destined to escape to space. But the water vapor from the gases would be slowed to down due to Mercury's gravity hanging onto them, which may result in them drifting towards Mercury's cold polar regions, causing them to freeze there. And over billions of years, the frost deposits (frozen water vapors from comets or volcanic outgases) may have built up the ice MERCURY'S INTERIOR:---Layers of Mercury's interior... Iron-nickel core (and perhaps sulfur), Silicate mantle, & Silicate crust ---The silicate skin on a large iron-nickel core is due to Mercury's density & gravitational field ---A rotating liquid core of iron & sulfur could explain Mercury's properties, such as, wobbles on it's axis and has a magnetic field. ------due to Mercury's liquid (molten) core is why Mercury wobbles a bit on its axis & has a magnetic field MERCURY'S ORBITAL PERIOD, ROTATIONAL PERIOD, SOLAR DAY, YEAR, ETC. : ---How long does it take from sunrise to sunrise on Mercury? Two orbital periods, a total of 176 Earth days (Reason: The combination of Mercury's 58.7 Earth day rotation period and its 88 Earth day revolution period results in a two-orbit solar day). ---One year on Mercury is...88 Earth days; shorter than a solar day on Mercury -One day on Mercury is... 176 Earth days, longer than its rotation period ---Mercury's solar day is twice as long as its year. ---True, as a result, sometimes the Sun travels backwards across the sky during the day (Reason: The Sun moves backwards near perihelion, when the orbital motion changes the Sun's position faster than the rotation). ---Mercury's orbital period is 88 Earth days. Rotational period is 58.6 Earth days. ---Tidal interactions between the Sun and Mercury have been important; The solar day (noon to noon) is 176 days; Mercury spins three times for every two orbits.

(Unit 1 - Our Planetary Neighborhood) Besides the Sun and planets, what other kinds of objects are members of the Solar System?

-In addition to the eight planets, the Solar System is filled with a vast number of smaller bodies, satellites (moons), asteroids, and comets.

(Outer Planets: Unit 45- Jupiter & Saturn) How do the gas giants masses and radii compare with Earth's

-JUPITER & Saturn are both about 10 times larger in diameter than Earth. Jupiter is mass is 300 times of Earth, while Saturn is only 100 times Earth's mass

(Inner Planets: Unit 43- Asteroids) What are the Kirkwood gaps? How were they formed?

-Kirkwood gaps are regions in the asteroid belt that are mostly empty because of orbital resonances with Jupiter or its best described as areas within the asteroid belt where Jupiter's gravity disturbs asteroid orbits -some gaps result from the gravititatonal force of Jupiter removing asteroids from orbits within gaps

(Inner Planets: Unit 40- Mercury) How do the craters on Mercury differ from the Moon's craters?

-Mercury's impact craters generally overlap less than the Moon's craters do in the lunar Highlands. -Mercury's crater walls tend to be less steep due it s surface gravity being 2x as strong as the Moon's surface gravity, making steep hills less stable on Mercury. -Congealed lava flows much on Mercury's surface while it is only found in the Maria on the Moon, and these lunar lava flows do not appear as dark as they do on the Moon and probably have a different composition from the Moon's basalt.

(Inner Planets: Unit 40- Mercury) Why does Mercury have no atmosphere? How does this affect Mercury's temperature?

-Mercury's temperature is very high & it's mass is very low -Mercury's no atmosphere bc of the planet's small size, which means its gravity is too weak to hold down a normal atmosphere. Mercury's thin atmosphere is constantly being "blown away" into space by the pressure of sunlight and by the solar wind

(Inner Planets: Unit 43- Asteroids) Where are asteroids found, other than in the main belt? What are their orbits like?

-Orbiting along Jupiter's path -Orbiting the Sun at a distance between 2 and 4 AU from the Sun

(Unit 39- Our Moon) What is odd about the Moon's rotations? Why does it spin like this?

-Rotates synchronously: The Moon must slowly rotate to keep the same features facing Earth. The Moon does NOT turn on its axis relative to the stars, but with a rotation period exactly equal to its orbital period, otherwise known as synchronous rotation. -This is common characteristic of satellites (moons) in the Solar System, which almost all keep one face toward their planet. The Moon rotates so one side is always facing Earth--this is side has a thinner crust and almost all of the Maria.

(Unit 38 - Earth's Atmosphere & Hydrosphere) What is the Coriolis effect? What motions does it affect? What motions does it NOT affect the student?

-The Coriolis effect: Air flows or even flying objects are deflected to the right in the northern hemisphere of a rotating planet, appearing to take a curved path because the ground below them is turning. -Coriolis effect affect's motions like: -Coriolis effect DOES NOT affect's motions like:

(Unit 39- Our Moon) How do astronomers now think the Moon formed? What evidence supports this hypothesis?

-The Moon's odd chemical composition suggests that it formed in a collision between a Mars-size object and the just formed Moon. -Lunar rocks brought back by the Apollo mission

(Unit 35 - The Origin of the Solar System) What is the Solar Nebula? What shape does it have, and why?

-The rotating disk of gas & dust from which the Sun & planets formed. -rotating disk-shaped cloud

(Inner Planets: Unit 41- Venus) How is Venus's rotation unusual? What might have caused this?

-Venus has a rotational period of 243 days and an orbital period of 225 days. It also spins backwards (retrograde) compared to the orbital motion · The Sun rises in the west · The solar day is shorter than the rotation period. · The stars that rise, rise in the west.

(Unit 1 - Our Planetary Neighborhood) What is a dwarf planet? Name two objects currently in this category.

-an object orbiting the Sun that is so massive that its gravity pulls it into a roughly spherical shape but, because it is not the dominant mass in the neighborhood of its orbit, it cannot be called a planet. -Pluto, Ceres, and Eris are considered dwarf planets. Several dozen trans-Neptunian objects (TNOs) may soon be added to that category.

(Inner Planets: Unit 43- Asteroids) Where are asteroids located? Why did they not form a planet?

-asteroid belt( a region between Mars & Jupiter.)' -due to jupiter's strong gravitational pull

(Inner Planets: Unit 42- Mars) What are the Martian polar caps composed of? Why do they show layering?

-carbon dioxide (dry ice) -by extending across a region extending up to 40 degrees from south pole (about 5000 km across) but less than 30 degree from the north pole (about 3500km across)

(Inner Planets: Unit 43- Asteroids) What is different about the shape of Ceres compared to other asteroids? Why is there this difference?

-is the largest of the asteroids -

(Unit 1 - Our Planetary Neighborhood) What are the eight planets in order of distance from the Sun?

1. Mercury (0.4 AU) [closest to the Sun] 2. Venus (0.7 AU) 3. Earth (1.0 AU) 4. Mars (1.5 AU) 5. Jupiter (5.2 AU) 6. Saturn (9.5 AU) 7. Uranus (19 AU) 8. Neptune (30 AU) [farthest from the Sun]

Earth (as a terrestrial planet)

1. The Earth's crust is approximately 45% oxygen by mass, making it the most common element in the crust. 2. Rounded to the nearest whole number, the density of silicate rock is about 3kg/L 3. Select the properties of S waves. · The slower of the two choices. · Wave motion is perpendicular to direction of travel. 4. Put the layers of Earth in order from the exterior (top) to the interior (bottom). · Crust · Mantle · Liquid core · Solid core 5. Rocks, which are made mostly of compounds of oxygen and silicon called silicates, are the most common materials in the Earth's crust. 7. Matching ----Solid rather than liquid or gas — Too much pressure to be anything else ----Made of iron and nickel —The densest materials sink to the core ----Radius is about 1200 km. — Seismic wave detection patterns 8. All the observations that lead us to believe that the Earth's interior is hot: ---Earth has active volcanoes. ----Earth has a magnetic field. Magnetic fields form from currents in a liquid metal core. ----Every 100 m we dig into the Earth, the temperature goes up 2 K. 9. Correct descriptions of the Earth's outer core. · Liquid (flowing) · About 1300 km thick · Mostly iron and nickel 10. What is the best explanation for why the Earth's inner core is solid, when the outer core is liquid? · It is under extremely high pressure. 11. What occurs when two tectonic plates pull apart (or the plate breaks and pulls apart), and mantle rock rises up into the gap to form new crust? This often happens in the middle of the oceans. · Rifting 12. Several hundred million years ago the Earth's continents were in very different locations (Reason: The landmasses on Earth move to form and break up very large continents from time to time.) 13. The circulation of material shown in the image is best described as convection. (Reason: Convection is a current that occurs when hot material decreases in density, moves upward from the heat source, cools, then sinks back down to be heated again.) 14. The temperature at the center of the Earth is believed to be 6000 K, as hot as the surface of the Sun. Primarily, astronomers believe this is because the Earth formed hot and has stayed hot because of its large volume (Reason: Because of its small surface area relative to its volume, the Earth loses heat slowly.). 15. Evidence that Earth's interior temperature increases with depth. ---Plate tectonics (Reason: Volcanoes and shifting plates only make sense if the mantle is hotter than the surface.). ---Direct temperature measurements in holes dug in the crust (Reason: We have not gone much deeper than 10 km, but the temperature goes up as you go down.). ---Models of planet formation. 16. Convection in the mantle can occur because the material in the mantle can flow. Material heated by the core can rise. 17. Rounded to the nearest whole number, the density of silicate rock is about 3 kg/L 18. True, Larger bodies cool more slowly than smaller bodies. (Reason: Compared to its total volume, a larger object has proportionally less surface area. The ratio of the surface area to volume determines how fast a body loses heat (the smaller the ratio, the slower the heat loss). 19. False, The Earth's outer core is a mixture of iron, nickel, and water. 20. The Hawaiian island chain is formed by a rising plume of melted rock (reason: The material forming the Hawaiian island chain comes from a plume of hot, melted rock rising to the surface in the mid-Pacific). · the Pacific plate moving west (Reason: The Pacific plate moving west results in a long line of Hawaiian Islands, rather than one big island.) 21. Why is Earth's mantle molten and its outer core liquid, while this is not true of the Moon or Mars? ---There are long-lived radioactive elements in the Earth. ---Earth formed hot and has a high ratio of volume to surface area. 22. Most continental mountain ranges on Earth are formed where plates collide and wrinkle. (Reason: Plates colliding and wrinkling create folded mountain ranges, the predominate type on Earth.) 23. The surface area of a spherical planet is 4πR2. The volume is V = 4343πR3. The ratio of the surface area to volume determines how fast a body loses heat (the smaller the ratio, the slower the heat loss). As a planet's radius increases, the ratio gets smaller by the same factor. (Reason: The ratio is equal to 3R. If R goes up by some factor, the ratio goes down by the same factor) 24. Match the features or events with how plate tectonics causes them: ---Earthquakes — --- Plates shift abruptly at boundaries. ---Continents move — --- Convection in the mantle drags the Earth's surface ----A chain of volcanic islands — --- Convection moves plates over rising plumes in the mantle ----Volcanoes on the U.S. Pacific Northwest coast — -- Ocean plates can be subducted under continental boundaries 25. About 255 hundred million years ago, nearly all of the seven continents we have today were joined into a single large mass called Pangea. 26. The features or events caused by plate tectonics: ---Erosion of surface rocks and soil (Reason: Erosion is a result of wind and water) ---New crust is formed (Reason: Fresh basalt is formed at the Mid-Atlantic Ridge). ---Folded mountains ---Earthquakes ----The Atlantic Ocean getting wider 27. Electrical currents in the molten (outer) iron core of Earth create Earth's magnetic field. (reason: moving electric charges (currents) create an electromagnetic field.) 28. The Earth's magnetic field is a result of... · Convection currents in the molten iron core. (Reason: Rotation and convection-induced currents in the molten iron core cause Earth's magnetic field.) 29. Earth's magnetic poles reverse occasionally & migrate slowly over the years. (Reason: Earth's magnetic field has reversed many times over the history of the planet and the magnetic poles move in an irregular pattern.)

(Inner Planets: Unit 43- Asteroids) What is Bode's rule, and how did it lead to the discovery of asteroids?

A formula that somewhat accurately predicts the orbital distances of the first eight major bodies in the Solar System and then somewhat predicts the next several is known as Bode's rule.

ion tail

A stream of ionized particles evaporated from a comet and then swept away from the Sun by the solar wind.

A typical short-period comet might return to the inner Solar System after 150 years. (Reason: Short-period comets have orbital periods of less than 200 years).

A typical short-period comet might return to the inner Solar System after 150 years. (Reason: Short-period comets have orbital periods of less than 200 years).

(Unit 34 - Structure of the Solar System) What is the Oort cloud? Where is it located, and what kind of objects come from it?

A vast region in which comet nuclei orbit. This cloud lies far beyond the orbit of Pluto and may extend halfway to the next nearest star. Objects that come from the Oort Cloud are comets, Sedna, a TNOs,

(Unit 34 - Structure of the Solar System) What is a dwarf planet?

An object orbiting the Sun that is so massive that its gravity pulls it into a roughly spherical shape but, because it is not the dominant mass in the neighborhood of its orbit, it cannot be called a planet.

Venus

Aphrodite— A continent-like highland region on the planet Venus. Fault—In geology, a crack or break in the crust of a planet along which slippage or movement can take place. Greenhouse gas— A molecule, such as carbon dioxide, methane, or water vapor, that efficiently absorbs infrared radiation. ---Results of Venus's greenhouse effect include: Little change in temperature from day to night; and Surface temperatures much hotter than can be explained by Venus's distance from the Sun. Ishstar—A continent-like highland region on Venus. Maxwell Montes— A set of mountains on Venus, including the tallest volcano; one of the first features detected by radar imaging. Pancake domes—Unusual surface feature on Venus , they appear as "blisters" of uplifted rock that may be produced by volcanic activity. Photodissociation— the breaking apart of a molecule by intense radiation. Radar imaging— is done through radio wavelengths, which Venus thick clouds do not stop radio waves. Retrograde spin— A spin backward from the unusual orbital direction. For example, seen from above their north poles, most of the planets orbit and spin in a counterclockwise direction; however, a few have a retrograde spin. Runaway greenhouse effect— An uncontrollable process in which the heating of a planet leads to an increase in its atmospheric greenhouse effect and thus to further heating. The process significantly alters the composition of the planet's atmosphere and the temperature of its surface. ---The runaway greenhouse effect is why Venus's atmosphere is extremely hot and dense. -Venus's thick crust may prevent tectonic activity, like tectonic plates, and possibly impact craters if there is geological activity happening to erase them. VENUS'S ATMOSPHERE: ---Temperature hotter than Mercury's near the surface; ---Clouds of sulfuric acid; and ---More than 90% CO2. ---The CO2 (carbon dioxide) atmosphere has created conditions for a runaway greenhouse effect, making Venus hotter than Mercury even though Mercury is closer to the Sun than Venus! ---In Venus's atmosphere and weather:Lightning occurs in the sky; and The surface temperature is in excess of 700 K. ---H2O rises to the top and is broken up by ultraviolet light, which is a process called photodissociation. ---Atoms do not re-form into water because the freed Hydrogen atoms are too light for Venus's gravity to hang on to, and many escape to space, and Oxygen eventually combines with Carbon (Reason: The hydrogen and oxygen that remain may eventually become part of sulfur compounds). VENUS'S FEATURES: ---Volcanic mountains ---Pancake (or lava) domes ---Continent-like masses ----Two small continents: Aphrodite & Ishstar. ----The unusual circular features found on Venus's surface are called pancake (or lava) domes. ---True, the surface has been mapped by radar, showing two small "continents" (Aphrodite & Ishstar) and smooth low-lying lava plains cover most of the surface VENUS'S INTERNAL HEATING: ---Venus's internal heat affects its surface by: =Rising plumes of melted rock stretch the surface and crack it and Domes, uplifted regions, and faults result; =The crust is too thick to break into plates and move, but convection in the mantle causes bulges, volcanoes, and wrinkles in the crust; and =Heat builds in Venus's interior, melting the underside of the crust, periodically, breaks occur and massive lava floods renew the surface. ---Radar images show volcanoes and crustal bulges from internal heating (but it is unclear when volcanic activity last occurred) METHODS USED ON VENUS:---Venus undergoes resurfacing by what method?Periodic Major Resurfacing Events (Reason: The internal heat of Venus builds until it is released in a major event) ---Methods astronomers used to observe Venus's surface: · Spacecraft Landers to photograph the surface (Reason: Soviet Venera missions between the late 1960s to the early 1980s obtained radar and a few photographic images of the surface) and; · Radar Mapping (Reason: The US orbiter Magellan, as well as ground-based telescopes on Earth, have used radar to penetrate the clouds and map the geology of the surface). ---We have mapped the surface of Venus by bouncing radar off the surface from satellites and Earth (reason: Venus's clouds are thick but do not block radio waves). ---True, Several Soviet spacecraft successfully transmitted images of the surface of Venus before succumbing to the intense heat and pressure of the Venusian surface. (Reason: Even though each only survived for a few hours, between 1970 and 1981, several Venera landers made it to the surface and transmitted pictures). VENUS'S RETROGRADE SPIN:---True, Venus rotates backwards slowly because of a major collision when it formed and is why 1 day for Venus is half the length of its year. —--Venus was struck late in the formation process by a large planetesimal. —--Venus retrograde spin is a result of tidal interactions with the Sun, Earth and other planets (Reason: Interaction with the Sun alone would not explain it, but detailed modeling shows once nearly tidally locked to the Sun, other planets could nudge Venus into the rotation observed). ---False, Tidal braking with the Sun is NOT sufficient to explain Venus' retrograde rotation. ---Consequences of the retrograde motion: The Sun rises in the west; The solar day is shorter than the rotation period; and Stars that rise, rise in the west. VENUS'S ROTATION:---It is retrograde compared to its orbit; ---It causes the solar day to be shorter than the rotation period and; ---One 360° turn versus the stars takes longer than a 360° orbit. ---Venus has a rotational period of 243 days, and an orbital period of 225 days. SIMILARITIES & DIFFERENCES BETWEEN EARTH & VENUS: [Similarities] ---A core made of iron-nickel and a mantle of rocky silicates ---Total mass of about 1 M⊕ --- size, density, and equatorial radius . [Differences]---Grids of narrow cracks and Pancake domes are not found on Earth as they are on Venus. ---Atmospheric density; —--Surface temperature; and —--Atmospheric composition (it is almost entirely carbon dioxide). Making venus atmosphere very different from earth's. WATER ON VENUS: —--Venus's water evaporated in the heat. —--Molecules drifted to the upper atmosphere and were split by ultraviolet light. ---The hydrogen escaped to space. ---Liquid water may once have been present, but it boiled away, and sunlight broke down the H2O (photodissociation) allowing the hydrogen to escape

Earth's Moon

Apollo mission results show that Moon and Earth rocks have differences; For example, Moon rocks have more high-melting-point materials and less low-melting-point materials. The Moon's density also suggests it has less iron than might be expected. What do these suggest is a likely model of the Moon's formation? Made of basalt * younger; 3 billion years old Describe how impact features are formed on the Moon: ---A meteorite or comet hits the Moon's surface at high speed. --These pre-Apollo mission hypotheses for the formation of the Moon make different predictions about the Moon's chemical composition. All that would be supported if the Moon had a composition identical to the Earth's. (In reality, the Moon's composition is similar, but too different for any of these models to be correct.) · Fission hypothesis (spun out from the Earth's equator) · Twin formation hypothesis (formed side-by-side) All lunar features thought to form as a direct or indirect result of impacts. Evidence against the "twin hypothesis" that the Earth and the Moon formed together side-by-side from a common cloud of gas and dust? The Moon has a lower fraction of iron than Earth does. All the features that are found on Earth's Moon are: Highlands, Maria, & Craters An asymmetry of the Moon's structure is that the crust is more than twice as thick on the far side than the near side. Match each prediction to the appropriate hypothesis of the Moon's formation: · Earth captured a fully formed Moon -- Earth and the Moon have very different chemical compositions. · The Moon formed from material spun off Earth due to Earth's rapid rotation -- The Moon has a chemical composition identical to Earth's crust. · The Earth and Moon formed side by side out of the nebula -- Earth and the Moon share many compositional similarities. · Late collision of a large planetesimal with Earth splattered mantle and crust material into orbit -- The Moon's composition indicates it was formed hot, but it has less iron than expected. The elements matched with regions on the Moon where they are likely to be concentrated (found): · Iron, titanium, magnesium -- Lunar mare regions · Calcium, aluminum silicates -- Lunar highlands · Hydrogen, helium -- Not prevalent on the Moon All lunar features that are thought to form as a direct or indirect result of impacts. · Craters · Maria · Lunar rays Lunar canyons, possibly carved by ancient lava flows, are known as rilles. Lunar canyons known as rilles are believed to have been formed by ancient lava flows & crustal cracking. The blanket of chunks of rock and fine rock powder that covers the Moon is called regolith. All processes that are important for forming lunar maria: ---Large objects hitting the Moon ---Lava from the mantle flooding craters on the early Moon

As a comet approaches the Sun, solar radiation causes ices on comet's surface to sublimate (The ices turn directly into gas

As a comet approaches the Sun, solar radiation causes ices on comet's surface to sublimate (The ices turn directly into gas

How would a comet nucleus be best described?

As a dirty snowball, loosely packed (Current estimates of the densities of comet nuclei are less than 1 kg/L. They appear to be loosely packed, at least for a good chunk of the volume, rather than solid ice).

Asteroid

Asteroid— A small, generally rocky, solid body orbiting the Sun and ranging in diameter from a few meters to hundreds of kilometers. Outer-belt asteroids and some meteorites contain carbonaceous materials and ice. Some asteroids were large enough to differentiate and subsequent collisions between asteroids have broken them apart. The largest asteroid is called a dwarf planet because of it's gravity that has pulled it into a round shape, like Ceres, but it has not cleared its orbit to be a planet. Asteroids have been cleared out from Kirkwood gaps, where orbits have a resonance with Jupiter's orbit (gravitational pull). Thousands of asteroids have orbits that come close to Earth's orbit, and astronomers are searching for any others. Asteroid's orbits have been determined for hundreds of thousands of asteroids, but are far more too small to have been detected yet. Asteroids composition and size and where they orbit: Size— small Composition— rocky bodies Orbit— Most orbit between Mars (inner planet) and Jupiter (outer planet) and their combined mass is much less than the Moon's mass. An asteroid would best be described as a small object made of rock and metal orbiting the Sun at a distance between 2 and 4 AU (Reason: Although some asteroids have ice, you have selected a better description of the icy bodies that orbit in the Kuiper belt (trans-Neptunian objects). True of asteroids in our Solar System: —Differentiated; —Mostly rock; —Orbit along Jupiter's path (Reason: The Trojan asteroids occupy stable points along Jupiter's orbit); —Mostly iron; and —Orbit between 2 & 4 AU from the Sun. Asteroids were discovered by a systematic search for a planet between Mars and Jupiter (Reason: The search was guided by Bode's rule). Achondrite— A story meteorite of rocky material from the upper layers of a differentiated body. Achondrites have no chondrules. Achondrite meteorites come from differentiated bodies (the Moon, Mars, or very large asteroids) because they contain no chondrules. The material has melted since it was in the Solar Nebula Spectral and chemical analysis of the objects matches analyses of the Moon, Mars, or specific asteroids. Achondrites are a type of meteorite made of materials that have been melted and differentiated in the formation of a large body or planet. They lack the chondrules found in meteorites that are leftover materials from the Solar Nebula (Reason: Chondrules are approximately millimeter-sized small round nodules). Asteroid family— A group of asteroids that appear to have originated from a single object that underwent a collision (killed the dinosaurs). The asteroids all have orbital parameters and spectroscopic properties that indicate they have similar compositions (makeups). Bode's Rule— A numerical formula for predicting the approximate distances of most of the planets from the Sun. Bode's rule provides a fairly accurate prediction of the orbital distances of the first eight planets A formula that somewhat accurately predicts the orbital distances of the first eight major bodies in the Solar System and then somewhat predicts the next several is known as Bode's rule.' Carbonaceous chondrite— A type of meteorite containing many tiny spheres (chondrules) of rocky or metallic material embedded in carbon-rich material. Carbonaceous chondrites contain organic compounds such as amino acids. These were not produced by living organisms but by physical processes due to the right- and left-handed forms that occur in equal numbers. If you found a meteorite that looked like a big lump of coal with a small round of rock nodules in it, you have found a carbonaceous chondrite Ceres— The first discovered and largest of the asteroids, over 900 km in diameter. Often was called a planet during the early 1800s. — Ceres is a dwarf planet Chondrite— A meteorite containing small spherical granules called chondrules. Chondrites are stony meteorites composed of rounded grains, flakes of metal, and rocky bits Chondrule— A small spherical silicate body embedded in many meteorites. Chondrules, rounded grains found in meteorites, are extremely useful to study because they are materials that formed directly in the Solar Nebula. DIFFERENTIATION: The existence of iron meteorites is evidence that what process must have occurred in at least some asteroids?" Differentiation (Reason: They are likely from the core of a differentiated asteroid). Evidence that some asteroids differentiated into cores and mantles? —Iron meteorites exists (Reason: Yes. The source of iron meteorites is believed to be the iron core of differentiated asteroids that were subsequently broken up into pieces). Iron— Core of a differentiated asteroid. Stony-Iron— Core mantle boundary of a differentiated asteroid. Achondrite— Mantle of a differentiated asteroid. Chondrite—Undifferentiated asteroid. METEORITE: Meteorite—The solid remains of a meteor that falls to Earth. True, some meteorites come from bodies that grew large enough to differentiate, making an iron core and crustal rocks. True, some meteorites appear to never have been melted, and contain chondrules that were grains of material in the solar nebula. A meteorite forms when a larger chunk of rock and iron from the asteroid belt survive the fiery trip from the Solar System to the ground on Earth, turning into a meteorite. KIRKWOOD GAPS: Kirkwood gaps— Regions in the asteroid belt with a lower-than-average number of asteroids. Some of the gaps result from the gravitational force of Jupiter removing asteroids from orbits within the gaps. Gaps appear in the asteroid orbital distances because —Jupiter's orbit is a simple multiple of the orbital period at the gaps and gravitational interactions that modify the orbits recur at the same location (Reason: An orbit in the gap would have an orbital period one-third (or one-fourth or one half, etc.) of Jupiter's. So every three orbits, an asteroid would be closest to Jupiter in exactly the same point in the orbit. Jupiter's gravity would pull on the asteroid, gradually elongating the asteroid's orbit). Kirkwood gaps are best described as areas within the asteroid belt where Jupiter's gravity disturbs asteroid orbits Near Earth Object— An asteroid with an orbit that crosses or comes close to Earth's orbit. Resonance— A condition in which the repetitive motion of one body interacts with the repetitive motion of another to reinforce the motion. For example, planets or satellites orbiting with orbital periods that have a simple fractional ratio are in resonance and can have a strong influence on each other's orbit. Trojen asteroids - Asteroids clumped in a region in Jupiter's orbit by the Sun's and Jupiter's gravity An object orbiting an asteroid allows us to find the asteroid's mass using Newton's laws. Examining spacecraft photos of asteroids from missions such as NEAR, you would be most likely to observe craters

(Unit 39- Our Moon) Why are the Maria and highlands so different in appearance?

Because Maria (the dark areas of the Moon) is smooth due being flooded with basalt after major impacts and is filled w basalt rocks and the Highlands (the light areas of the Moon) are heavily cratered with rocks composed of high calcium and alumin silicates

(Inner Planets: Unit 43- Asteroids) What are chondrules, and what do they indicate about conditions in the Solar Nebula?

Chondrule— A small spherical silicate body embedded in many meteorites. Chondrules, rounded grains found in meteorites, are extremely useful to study because they are materials that formed directly in the Solar Nebula, and indicate the conditions in the the Solar Nebula are.. they are some of the oldest material in the solar syste, explosion triggered collapse of Solar Nebula. Solar Nebula contained a disk of hot gas full of small rocky pebbles, and metal flakes.

Comets from the Oort cloud might develop elliptical orbits and arrive in the inner Solar System as a result of gravitational interactions with other nearby stars in the Milky Way and dwarf planets that orbit in the Oort cloud

Comets from the Oort cloud might develop elliptical orbits and arrive in the inner Solar System as a result of gravitational interactions with other nearby stars in the Milky Way and dwarf planets that orbit in the Oort cloud

Compared to the Kuiper belt, the Oort cloud is... · about 2000 times farther from the Sun (reason: The Oort cloud is at about 100,000 AU.) · more nearly spherical · colde

Compared to the Kuiper belt, the Oort cloud is... · about 2000 times farther from the Sun (reason: The Oort cloud is at about 100,000 AU.) · more nearly spherical · colde

Each time a comet passes by the Sun, it loses the material that forms the tail, parts of the nucleus experience outbursts, explosions, and melting

Each time a comet passes by the Sun, it loses the material that forms the tail, parts of the nucleus experience outbursts, explosions, and melting

(Inner Planets: Unit 41- Venus) Contrast the magnetic fields of Earth, Mercury, and Venus, and explain why these magnetic fields are so different.

Earth has as a moderately strong magnetic field, and Venus and Mars have almost no measurable fields.

(Unit 37 - Earth as a Terrestrial Planet) What generates the magnetic field of Earth?

Electrical currents in the molten (outer) iron core of Earth create Earth's magnetic field. (reason: moving electric charges (currents) create an electromagnetic field.) · Convection currents in the molten iron core. (Reason: Rotation and convection-induced currents in the molten iron core cause Earth's magnetic field.) . Earth's magnetic field is the result of convection currents in the molten iron core. (Reason: Rotation and convection-induced currents in the molten iron core cause Earth's magnetic field)

Uranus & Neptune

Great dark spot: A large atmospheric vortex discovered on Neptune, similar to Jupiter's Great Red Spot. The spot was discovered by the Voyager II spacecraft in 1989 but has since disappeared. Ice giant: A term used to distinguish Uranus and Neptune form the gas giants Jupiter and Saturn. The name is descriptive of their composition, which suggests that they formed from the accretion of icy planetesimals. Despite the name, these planets have interiors hotter than Earth's interior. Uranus and Neptune are the only major planets in our Solar System that were discovered since ancient times True, Uranus and Neptune are similar in size. They are also about 4 times Earth's diameter AND their masses are about 16 times Earth's mass. Uranus and Neptune are called ice giants because their composition suggests they probably formed from icy planetesimals and captured much less gas than the gas giants, Jupiter or Saturn. Although methane causes these planets to be blue, their atmospherse are mostly consist of? Hydrogen (80%) and Helium (15%) Uranus and Neptune rotate rapidly, showing evidence of? Uranus and Neptune rotate rapidly, showing evidence of atmospheric bands and storm systems, however much of this detail is hidden beneath the methane haze. Due to rapid rotation, both Uranus and Neptune show evidence of atmospheric bands and storm systems, however, much of this detail is hidden beneath Methane Haze The methane haze on both Uranus and Neptune hides much detail of atmospheric bands and storm systems, which are caused by both planets rapid rotation. Uranus's rotation axis is almost...Uranus's rotation axis is almost sideways, leading to large seasonal changes in solar heating Uranus's almost "sideways" rotation axis leads to large seasonal changes in solar heating. Both Uranus and Neptune have peculiar magnetic fields that do NOT align with the rotation axis; Thus, their peculiar magnetic fields may be generated in what layer? in the internal water layer Why do Uranus and Neptune have a higher percentage of Helium than their more massive neighbors, Jupiter and Saturn? because they were built primarily by accumulating icy planetesimals Methane freezes into a haze of crystals in Uranus's and Neptune's atmosphere because their outer atmospheres are so cool (cold) (much cooler than Saturn's or Jupiter.)

(Unit 38 - Earth's Atmosphere & Hydrosphere) What is the greenhouse effect? How does it relate to global warming?`

Greenhouse effect: · slows the rate at which energy that heats Earth is lost (radiated into space) · traps infrared radiation in the atmosphere · is stronger when there is more water vapor and carbon dioxide in the atmosphere

(Inner Planets: Unit 42- Mars) Why is it impossible for Mars to have liquid water on its surface today?

Impossible for mars to have liquid water on its surface due to... · Low gravity allows gas to escape. · The weak magnetic field allows the solar wind to strip gas. · Major asteroid impacts disrupted the atmosphere

(Outer Planets: Unit 45- Jupiter & Saturn) How are the interior structures of Jupiter and Saturn similar? How do they differ?

Inside Jupiter and Saturn, extreme pressure creates a layer of highly compressed., metallic hydrogen. List each layer and its properties: · It plays a role in creating the planet's magnetic field (Reason: The size of the layer is why Jupiter's field is incredibly strong compared to Earth's.) · It is a liquid. · Electric currents can flow in it. differ: in jupiter its average density is only slightly greater than that of water--1.3 kilograms per liter. For saturn, the density is lower than the density of water--0.7 kilograms

Ion tails of comets glow through fluorescence. The process is also why fluorescent paint looks bright at twilight or under a blacklight. It happens when ultraviolet photons excite electrons in atoms to high-energy orbitals. The electrons emit multiple lower-energy photons as they drop back down (Reason: In fluorescence, the electrons are excited by external radiation).

Ion tails of comets glow through fluorescence. The process is also why fluorescent paint looks bright at twilight or under a blacklight. It happens when ultraviolet photons excite electrons in atoms to high-energy orbitals. The electrons emit multiple lower-energy photons as they drop back down (Reason: In fluorescence, the electrons are excited by external radiation).

(Inner Planets: Unit 42- Mars) How does Mars compare with Earth in mass & diameter?

Mars diameter is only about half the size of Earth's diameter and mass is about one-tenth of Earth's mass.

(Inner Planets: Unit 42- Mars) What is the Martian atmosphere like?

Mars' atmosphere has a percentage of carbon dioxide that is much higher than Earth's and about the same as Venus'.

(Inner Planets: Unit 40- Mercury) How can Mercury's day be longer than its year?

Mercury rotates very slowly, spinning three times for every two orbits, making its day longer than its year

(Unit 37 - Earth as a Terrestrial Planet) How does plate tectonics cause earthquakes and volcanoes?

Plates shift abruptly at boundaries

Several hundred million years ago the Earth's continents were in very different locations

Several hundred million years ago the Earth's continents were in very different locations

Shower meteors seem to come from one point on the sky, the radiant, because the shower is caused by the Earth running into a concentration of debris. (Reason: The meteors come from debris along a comet's orbit. The Earth crosses the orbit, so the meteors all contact the atmosphere from the same direction).

Shower meteors seem to come from one point on the sky, the radiant, because the shower is caused by the Earth running into a concentration of debris. (Reason: The meteors come from debris along a comet's orbit. The Earth crosses the orbit, so the meteors all contact the atmosphere from the same direction).

(Unit 34 - Structure of the Solar System) How are asteroids and TNOs similar? How do they differ?

TNOs, (trans-neptunian object) is an object orbiting in the Kuiper belt or outer Solar System with a semi major axis larger than Neptune's. These include Pluto and many other objects ranging up to sizes even larger than Pluto. Whereas an asteroid is a small, generally rocky, solid body orbiting the Sun and ranging in diameter from a few meters to hundreds of kilometers

(Unit 34 - Structure of the Solar System) What properties distinguish the terrestrial from the Jovian planets?

Terrestrial planets are small, rocky planets, with relatively thin or no atmospheres. While Jovian planets are giant, mostly gaseous planets (Jupiter, Saturn, Uranus, & Neptune) The term Jovian, means Jupiter-like and is based on "Jove," an alternative name of Jupiter.

The Kuiper belt is the source of short-period comets. It also contains many times more mass than the asteroid belt, has objects with orbits of varied inclinations but that are fairly close to the plane of the Solar System, and is home to the TNOs in addition to other icy bodies

The Kuiper belt is the source of short-period comets. It also contains many times more mass than the asteroid belt, has objects with orbits of varied inclinations but that are fairly close to the plane of the Solar System, and is home to the TNOs in addition to other icy bodies

The Sun plays a role in creating both tails of a comet. Radiationpressure from sunlight pushes particles out of the coma to form the dust tail of a comet, but the ion tail is shaped by the solar wind

The Sun plays a role in creating both tails of a comet. Radiationpressure from sunlight pushes particles out of the coma to form the dust tail of a comet, but the ion tail is shaped by the solar wind

the process of fluorescence

The gases in the tail absorb ultraviolet light from the Sun. · The energy from an ultraviolet photon lifts an electron bound to a gas atom up several energy levels · The electron spontaneously drops back down, stopping at an intermediate level and emitting a lower energy visible light photon. The electron takes additional steps back down, emitting additional visible or lower-energy light rays until it is back to where it started.

The object Oumaumau passed inside the orbit of Mercury in September 2017 and showed evidence of acceleration in its trajectory. It is small, shows variations in brightness, and was traveling very fast compared to the typical Solar System object. Based on this evidence astronomers believe it might be a comet from outside our Solar System

The object Oumaumau astronomers believe it might be a comet from outside our Solar System because evidence of acceleration in its trajectory. It is small, shows variations in brightness, and was traveling very fast compared to the typical Solar System object. It was traveling too fast to have come from the Oort cloud.

(Unit 1 - Our Planetary Neighborhood) Which planets are most similar to Earth?

Venus and Mars

What usually happens when small rocks or chunks of ice enter Earth's atmosphere? Friction with the atmosphere heats them, causing a "shooting star" to appear

What usually happens when small rocks or chunks of ice enter Earth's atmosphere? Friction with the atmosphere heats them, causing a "shooting star" to appear

Where would you find a comet that has a long tail? · At the orbit of Earth · Inside the orbit of Mercury

Where would you find a comet that has a long tail? · At the orbit of Earth · Inside the orbit of Mercury

Halley's comet

a comet that reappears about every 76 years, famous because it was the first comet whose return was predicted

Long-period comet

a comet whose orbital period is longer than 200 years. these comets may originates from the Oort Cloud.

(Unit 1 - Our Planetary Neighborhood) Astronomical unit (AU)

a distance unit based on the average distance of Earth from the Sun

(Unit 35 - The Origin of the Solar System) What hypotheses explain why some terrestrial planets have atmospheres and other do not?

because gases and liquids were brought to those planets by comets, creating an atmosphere while the planets w/o an atmosphere were not. OR Small terrestrial planet has a lower escape velocity than a large one, so it. cannot hold on to an atmosphere as effectively. Smaller planets have less volcanic activity, so there is less volcanic outgassing to start with. THUS IF THERE IS NO SOURCE OF REPLENISHMENT ALL TERRESTRIAL PLANETS WOULD EVENTUALLY LOSE THEIR ATMOSPHERES. OR LOW MASSES.

(Unit 39- Our Moon) Why is the Moon so much less active than Earth?

because it cannot retain internal heat as effectively as Earth can due to its cooler internal temperatures which are a result of its mass being only about 1/8 of Earths and radius only one quarter of Earth's.

(Inner Planets: Unit 43- Asteroids) How do we know that asteroids are similar to some meteorites in composition?

because of differentiation and asteroid collisions

(Inner Planets: Unit 43- Asteroids) How do we know what asteroids are made of?

because of meteorites.

Unit 39- Our Moon) Why are craters so much larger than the impacting disability?

because of the kinetic energy released. the kinetic energy released in an impact by an asteroid is 1 kilometer in diameter---roughly a million times the enrgry release d by an atomic bomb dropped on Hiroshima. Whereas the size of an impact crater reflects the kinetic energy released and is usually about 10 to 100 times the diameter of the impacting object.

(Outer Planets: Unit 46- Uranus & Neptune) Why are Uranus and Neptune blue?

by a deep layer of methane

(Unit 34 - Structure of the Solar System) How does the density of an object provide clues to its composition?

by understanding the objects volume and mass...

(Unit 37 - Earth as a Terrestrial Planet) What is meant by plate tectonics?

cause shifting and is evidence that Earth's interior temperature increases with depth...

Mars

demios: One of the two small moons of Mars, probably a captured asteroid. laminated terrain: Alternating layers of ice and dust seen in the ice caps of Mars. The layers appear to reflect climate changes caused by long-term orbital variations. Olympus Mons: A volcano on Mars, the largest volcanic peak in the Solar System. Phobos: One of the two small moons of Mars, thought to be a captured asteroid. Its close orbit will cause it eventually to spiral into the planet. Tharsis bulge: A large volcanic region on Mars rising about 10 km above surrounding regions. Valles Marineris: A canyon feature on Mars stretching thousands of kilometers. MARS'S ATMOSPHERE: -Mars' atmosphere has a percentage of carbon dioxide that is much higher than Earth's and about the same as Venus'. -Possible explanations for how Mars has lost so much of its atmosphere.... · Low gravity allows gas to escape. · The weak magnetic field allows the solar wind to strip gas. · Major asteroid impacts disrupted the atmosphere -Mars's thinning atmosphere, several billion years ago allowed... the surface to cool to below the freezing temperature of water. -The atmosphere is now too thin for liquid water to remain the surface of Mars, but....There may be seepage from underground -Match the property of Mars to how it affects the density of Mars's atmosphere over time: · Small mass — A low escape velocity means molecules in the atmosphere can escape · Weak magnetic field —The solar wind can directly interact with the upper atmosphere, stripping it · No recent volcanic activity —The atmospheric gases are not replenished regularly. · No plant life or rain —Carbon dioxide stays in the atmosphere. -About how dense is Mars's atmosphere, compared to the Earths? · 1% (Reason: Mars likely had more atmosphere in the distant past, but with a weak magnetic field and a small mass, it easily loses gas to space). MARS'S INTERIOR: -Mars' interior is most similar to... Earth and Venus (Reason: Mars has a partially molten core about half the radius of the planet, composed mainly of iron and surrounded by a rocky mantle and a silicate rock crust). -The interior of Mars appears to have...Cooled, but volcanic activity may still have occurred in the last few hundred million years. MARS & EARTH: -Comparisons of the Earth and Mars... · Both planets have four seasons. · Temperatures are sometimes above 0° C. · The length of a solar day is similar (Reason: Mars's day is only 40 minutes longer than Earth's). -In Mars's surface conditions, rotation period, and axis tilt, Mars is more similar to Earth than any other planet in our Solar System. -The dream of many science fiction stories is that it might be possible to "terraform" Mars (to make it more like Earth) so that its environment would be suitable for humans. How might this be done? Seeing if there is seepage underground to find a resource of water to live on Mars. MISSIONS' ON MARS:· Curiosity rover — Climbed Mt. Sharp, a water- and wind- eroded sedimentary mound inside a crater. · Opportunity rover — Studied martian "blueberries", which are hematite nodules that form in water. · Spirit rover — Found minerals in layered rock outcrops that appeared to be formed through sedimentary processes. · Phoenix lander — Scooped up and chemically analyzed surface rock, exposing sub-surface ice. · Sojourner rover (Pathfinder lander) — Demonstrated we could operate a robotic rover on Mars Viking 1 and 2 — First successful landers, took pictures in 1976 · Pathfinder — Launched the Sojourner rover to explore a dead flood plain · Mars Odyssey — Orbiter that mapped hydrogen (interpreted as being in H2O) under the surface · Spirit & Opportunity — Rovers that explored valleys, plains, and craters, analyzing rocks and soil -The Mars rovers, Spirit and Opportunity successfully found evidence that... liquid water was once present on the surface of Mars. (Reason: The Rovers found evidence liquid water was present on the surface in the past). · Mars Reconnaissance Orbiter — Orbiter capable of taking high-resolution images of the surface showing few meter-sized features MARS'S MOONS (SATELLITES): -All that is true about the Martian moons: · They are only a few tens of kilometers across. · They are named Phobos and Deimos. · Their surfaces have craters and dust -Mars has two small moons that may captured asteroids or debris from a....Collision like the one that created our Moon. -Statements that are true about Mars's moons: · They have craters on their surfaces. · They are likely to be captured asteroids. · They are not spherical. -True or false: A moon that orbits a planet faster than the planet rotates will rise in the west and set in the east, if both are moving counterclockwise as seen from above. · True (Reason: This is true of Phobos, one of Mars' moons). MARS'S SEASONS: -Seasonal changes on Mars.... Dust storms are more common during the southern summer. · Laminated terrain forms near the poles. · The polar caps shrink in the summer. -Causes Mars's seasonal changes: · Orbital shape (Reason: Mars's distance to the Sun changes 20% over its orbit) · Axial tilt of 25 -The warmest temperatures on Mars are about 10°C (283 K or 50°F), chilly but comfortable (Reason: During a warm time of year, the temperature at the Martian equator is quite reasonable. Unfortunately, the atmosphere is still only about 1% as dense as Earth's). -Winds occasionally raise global dust storms that have covered the entire planet with red dust. MARS'S SURFACE: -Mars once had large bodies of water on its surface, what observations support this? · Compounds that form in water have been detected using spectra. · Images show features that appear to be dried-up river channels or lakes. · Substantial ice is currently present in the polar caps and under the surface. · Mars -What materials besides water ice might explain the Hydrogen detected on Mars's surface by the Odyssey spacecraft? Would these be likely? Mars probably had extensive liquid water on its surface when it was young. -Surface features imply that Mars once had bodies of...Liquid water, flowing streams, and deposited layers of sedimentary rock. -Today we think that liquid water cannot exist on Mars due to the low atmospheric pressure. Evidence that ice is present at or near the surface: · Ground-penetrating radar found the polar caps are mostly water ice. · Landers have excavated ice (Reason: The Phoenix lander dug up ice in 2008).

(Unit 34 - Structure of the Solar System) What is meant by a volatile substance, and why would we expect to find objects made out of volatile substances far from the Sun?

element or compound that vaporizes at low temperature. Water and carbon dioxide are examples of volatile substances that form solids far from the Sun

(Inner Planets: Unit 43- Asteroids) What kinds of meteorites come from differentiated asteroids?

iron meterorites.

(Unit 39- Our Moon) What are the effects of tides on Earth and on the Moon

moonquakes or earth quakes.

fluorescence

the conversion of ultraviolet light (or other short-wavelength radiation) into visible light. This occurs, for example, when an atom is excited into a high energy level by an ultraviolet photon, and then descends to the ground state in a series of steps, emitting lower-energy photons.

coma

the gaseous atmosphere surrounding the head of a comet

(Unit 37 - Earth as a Terrestrial Planet) How do the ways in which P waves and S waves propagate indicate the internal structure of Earth?

the seismic waves...? waves generated in earth interior by earthquakes. similar waves occur in other bodies. two of the more important varieties are S and P waves. S waves travel only through solid material and P waves travel through solid or liquid material

(Unit 35 - The Origin of the Solar System) What is differentiation? Why is it more likely to have occurred in the larger bodies in the Solar System?

the separation of previously mixed material inside a planet or other object. An example of differentiation is the separation that occurs when a dense material, like iron, settles to the planet's core, leaving lighter material on the surface. Differentiation is more likely to have occurred in the larger bodies in the Solar System because ...?

sublimate

to charge directly from a solid into a gas without passing through a liquid phase

Math the parts of a comet to their approximate sizes: gas and dust tails, hydrogen envelope, coma, and nucleus.

· 10 km - nucleus · 100 million km - gas and dust tails · 100,000 km - coma · 10 million km - hydrogen envelope

Measurements indicate that since the 1700s, the Earth's magnetic field has weakened by about how much?

· 10%.

(Inner Planets: Unit 41- Venus) How does Venus compare with Earth in mass & radius?

· A core made of iron-nickel and a mantle of rocky silicates Total mass of about 1 M

(Inner Planets: Unit 41- Venus) How does Venus's surface differ from Earth's? How have astronomers determined what the surface of Venus is like?

· Atmospheric density · Surface temperature · Atmospheric composition · Grids of narrow cracks (feature on Venus) · Pancake domes (feature on Venus) · Volcanic mountains (feature on Venus) · Pancake domes (feature on Venus) · Continent-like masses (feature on Venus) -with infrared radar imaging (wavelengths)

(Inner Planets: Unit 42- Mars) What is the evidence that Mars once had running water on its surface? Is there evidence for water in any form today?

· Compounds that form in water have been detected using spectra. · Images show features that appear to be dried-up river channels or lakes. · Substantial ice is currently present in the polar caps and under the surface. · Mars no.

(Unit 37 - Earth as a Terrestrial Planet) What factors cause the interior of Earth to be hot?

· Earth has active volcanoes. · Earth has a magnetic field. Magnetic fields form from currents in a liquid metal core. · Every 100 m we dig into the Earth, the temperature goes up 2 K.· Plate tectonics (Reason: Volcanoes and shifting plates only make sense if the mantle is hotter than the surface.). · Direct temperature measurements in holes dug in the crust (Reason: We have not gone much deeper than 10 km, but the temperature goes up as you go down.). · Models of planet formation.

(Inner Planets: Unit 42- Mars) What evidence indicates that Mars was once geologically very active but has been geologically inactive for hundreds of millions or billions of years?

· Giant volcanic mountains such as Olympus Mons · Giant rifts such as the Valles Marineris

(Outer Planets: Unit 45- Jupiter & Saturn) What is the source of internal heat for Jupiter and Saturn?

· Jupiter and Saturn have large volumes that cool slowly. · Gravitational energy is released as the planet contracts. · Differentiation releases gravitational energy.

(Unit 37 - Earth as a Terrestrial Planet) What s the evidence that Earth's magnetic field has undergone dramatic changes over time?

· Minerals in lava preserve the orientation of the Earth's magnetic field at the time the lava solidified. (Reason: When lava cools, the orientation is preserved in the rocks.)

· Perseids - August meteor shower associated with comet Swift-Tuttle · Meteor - Particle of asteroid or comet burning up in the atmosphere · Radiant - Point on the sky from which meteors in the shower seem to diverge · Meteor shower - Many meteors associated with particular debris in the Earth's path hitting the atmosphere over a few hours. · Geminids - A shower in December with many meteors per hour

· Perseids - August meteor shower associated with comet Swift-Tuttle · Meteor - Particle of asteroid or comet burning up in the atmosphere · Radiant - Point on the sky from which meteors in the shower seem to diverge · Meteor shower - Many meteors associated with particular debris in the Earth's path hitting the atmosphere over a few hours. · Geminids - A shower in December with many meteors per hour

What is the source of materials for a comet's tail?

· Sublimated (evaporated) material from the nucleus (Sublimation is changing directly from solid to gas. It is what happens to some of the ices in a comet's nucleus as it comes close to the Sun. The gas and dust freed from the nucleus make the comet's tail.)

All that happen to charged particles from the Sun when they encounter Earth's magnetic field.

· They move in spirals around the magnetic field lines and can create auroras · Some are deflected by the magnetic field and go around Earth. · Many are trapped in the Van Allen belts.

(Outer Planets: Unit 45- Jupiter & Saturn) What is the Great Red Spot? Why has it persisted for centuries?

· has been observed for over 300 years · is a high-pressure vortex · changes color and size over the years