Astronomy 115 Exam 2 Study Guide
What are the inhabitants of the Kuiper Belt called?
"Kuiper Belt Objects", or KBO's
What are the basic "ingredients" for making the solar system objects? What are some examples of each "ingredient"? Be able to give each average density
"metals" with the average density of 10 gm/cm3 (iron, nickel) "rocks" with an average density of 3 gm/cm3 (silicates mixed with magnesium, sulfur,...) "gasses" with the average density of < 1 gm/cm3 (hydrogen, helium) "ices" with the average density of 1 gm/cm3 (water-H2O, carbon dioxide-CO2, ammonia-NH3, methane-CH4) ~Mixtures of different proportions of these building materials can match the observed average densities of objects.
What are the four outer planets? What are the other planets called?
-Jupiter -Saturn -Uranus -Neptune Jovian planets
What is Earth's surface temperature?
-Max = 134 degrees F (Death Valley, 11915) 330 K -Min = -136 degrees F (Antarctica, 2010) 190 K - Global Average Annual (2013) = 58 degrees F
What is Mars's approximate temperature range?
-Max = 70 degrees F -Min = -220 degrees F -means surface temperature ~ -60 degrees F
What is the surface temperate of Mercury?
-Max = 800 degrees F -Min = -280 degrees F -highest temp range of all planets at 1080 degrees F
Describe Jupiter's interior.
-Mostly hydrogen -outer mantle - liquid hydrogen -inner mantle - liquid metallic hydrogen -core - "ices" and rock materials
Give examples of various visits with asteroids
-Near Earth Asteroid Rendezvous ~Eros - 33 x 13 x 13 km: Boulders on bottom of 5.3 km wide crater on Eros / The NEAR probe took this image from an altitude of 250 meters, and then crash-landed on the surface of Eros ~DAWN at Vesta -the space craft "Dawn" was placed into orbit around (4) Vesta in 2011. This image shows an apparent landslide (near the center): -Dawn's next goal is to fly on to Ceres and study it in 2015
Explain the formation of the Jovian Planets
-The Jovian Planets are believed to have formed from "seeds" consisting of rocky, metallic objects (similar to our current Terrestrial Planets, formed by millions of years accretion) -Jupiter formed at a distance of about 3AU, which is just outside of the snow line. Here, Jupiter accumulated huge amounts of hydrogen and helium. Jupiter used up most of the available raw material before the other planets formed. (Jupiter's current distance from the Sun is about 5AU) -Saturn was the next to form millions of years after Jupiter. At this time, it was much closer to Jupiter than it is now -Neptune was the third planet to form -Uranus was the last of the Jovian Planets to form. Uranus and Neptune must have had less hydrogen and helium available to them compared to Jupiter and Saturn. Gravitational interplay allowed the Jovians to migrate to their current positions. This resulted in Uranus and Neptune switching positions, leaving Neptune as the outermost planet.
Describe the formation of the Inner Planets
-The Terrestrial planets must have formed somewhat after the Jovians as a result of collisions of Moon-sized "planetesmales" of rocky/metallic composition aided by debris spirling in from beyond the snow line as the 4 giants' orbits changed. They were built from "seeds" in nearly circular orbits, or the collision process favored the survival of planetesimals in low-eccentricty orbits. (one of the last major collisions with Earth apparently led to the creation of the Moon). The Terrestrial planets reached their current diameters by about 4.1 billion years ago -Then the "Late Heavy Bombardment" began. It was fueled by debris cast inward from beyond the now line by the migration of the Jovians. It ended by 3.8 billion years ago. Any surface water came from the icy planetesmials from beyond the snow line. Only Earth retains significant amounts of this liquid water in its vast, deep oceans.
What are the physical properties of Earth's Moon?
-diameter = ~2,000 miles (~1/4 Earth's diameter) -mass = ~1/81 Earth's mass -average density = 3.3 gm/cm3 (3,300 kg/m3) -surface gravity = ~1/6 Earth's (1/6 g)
List and describe the physical properties of Earth
-diameter: ~ 8,000 miles. -mass: ~ 6 sextillion metric tons (6x10^24 kg). -average density: 5.5 gm/cm3
What are the physical properties of Pluto?
-diameter: ~1/5 of Earth's -mass: <1% of Earth's -average density: ~1.8 g/cm3
Describe Mars's surface features.
-heavily cratered Southern hemisphere -smoother and has volcanic domes in Northern hemisphere -N and S hemispheres are separated by Valles Marineris (Valley of the Mariners) ~3,000 miles long and 120 miles wide and about 4 miles deep -largest mountain in solar system in Olympus Mons (Mt. Olympus). Stands ~16 miles tall and its base covers ~36 miles. It also is an extinct Volcano
What is Earth's Moon's surface temperature?
-max = 265 degrees F (~400 K) -min = -300 degrees F (~100 K)
Give examples of types of meteorites
-stony -iron -stony-iron
Describe the estimated conditions of the center of the Earth.
-temperature = ~5,000*K. -pressure at the center = ~20,000 tons/in2 -central density = ~17 gm/cm3
Describe Mars's atmosphere
-thin and dry -mostly made up of CO2 (~95%) -surface pressure of only 0.006 bars
Be able to list and describe the various lunar surface features
1) Craters on the surface of the Moon were formed by a high speed impact of solid debris, such as asteroids and meteoroids 2) Maria (Mare-singlular) are described as "seas" on the surface of the Moon. These "seas" are actually solidified lava plains 3) Mountains/Mountain ranges on the Moon's surface were not formed by the same process as moountain ranges formed on Earth. These mountains are actually rims of huge ancient craters 4) rays are white/light colored streaks emanating from impact craters 5) Rilles, visible from Earth, resemble fine line cracks. They are actually long canyons formed by lava flows from collapsed lava tubes
What are the four layers of Earth's interior?
1) Crust 2) Mantle 3) Outer core 4) Inner core
Be able to describe the possible explanation for the origin of the Moon.
1) Fission: the Moon split off from the Earth 2) Capture: the Moon formed elsewhere and was captured by Earth's gravity 3) Co-creation [sister]: the Moon and the Earth accreted at the same time. The Moon developed from particles that were in orbit around the forming Earth 4) Collision-Ejection Theory: the Moon may have formed when the young, differentiated Earth was struck with a glancing blow by a young, differentiated proto-planet the size of Mars. The material coalesced to make the Moon
What is the order of the formation of the outer planets?
1) Jupiter 2) Saturn 3) Neptune 4) Uranus
What are the two satellites of Mars?
1) Phobos -the larger of the 2 satellites -max dimensions is ~16 miles -it is irregular shaped and heavily cratered 2) Deimos -the smaller of the 2 satellites -max dimensions is ~10 miles -irregular in shape and heavily cratered
What is Jupiter ideal for the production of a magnetic field?
1) fast rotation 2) fluid interior 3) metallic hydrogen -these compounds make the largest and strongest magnetic field of all the planets
What are the four ways you would describe the orbits of the 8 major planets?
1) nearly in the same plane/ecliptic 2) in the same direction 3) nearly circular 4) regularly spaced [not equally]
What are some difficulties associated with searching for exoplanets?
1) the angular separation between the parent star and the planet will be very small 2) the star will far outshine any of its planets
How long does it take Jupiter to revolve/rotate?
12 years/10 hours
What is Earth's surface pressure?
14.7 lb/in2 (1 "bar")
How long does it take Neptune to revolve/rotate?
165 years/~16.1 hours
how long does it take Venus to make a full revolution/rotation?
225 days/243R days (retrograde motion-spins backwards)
How long does it take Pluto to revolve/rotate?
249 years/6.4R days
How long foes it take for Saturn to revolve/rotate?
29.5 years/10.6 hours
How long does it take Mercury to make a complete revolution/rotation?
3 "spins" on its axis every 2 "obits" of the Sun
How many rings does Saturn have?
3 ring system has been resolved into multitudes of smaller ringlets, including the outer F-ring. Patterns of small pieces of ice-coated rock make up Saturn's rings. Voyager probe in 1980 showed radial dark streaks known as "spokes" on Saturn's rings
How many rings does Jupiter have?
3 rings
How big is Mercury compared to Earth?
4/10ths of Earth's diameter
How many rings does Neptune have? What are they made of?
5 rings and 4 partial rings, also known as "arcs". They are made of very dark material, similar to Uranus
How long does it take Mars to revolve/rotate?
687 days/24 hrs 39 mins and 35 sec
How long does it take Uranus to revolve/rotate?
84 years/17.24 hours
What is a comet? What are comets composed of?
A comet is believed to be a mixture of frozen gas, ices, and small solid particles. When far from the Sun, this tiny "nucleus" is too faint to be seen: -but as the nucleus crossed the orbit of Mars, heat from the Sun is sufficient to begin to vaporize frozen material and drive off gas and dust to form a "coma" and 1 or 2 "tails": -comet tail(s) always point away from the sun, even on the outbound leg
How is Gravitational "Microlensing" used as a detection technique by astronomers?
According to Einstein's General Theory of Relatively, a solar type star and its exoplanet can cause a temporary brightness flare of a much more distant star as the parent star and its exoplanet pass over it.
Give a description of Ceres
Also known as the largest asteroid, it is 940 km (585 miles) in diameter. It has also been re-classified as a dwarf planet. Eris, Haumea, Makemake are other dwarf planets residing in the Kuiper Belt. Eris may be slightly larger in diameter than Pluto. It has a small satellite named Dysnomia. Haumea also has two small satellites.
What is the cause of Venus and Uranus spinning in retrograde motion?
Astronomers believe that Uranus was struck by an object a long time ago causing it to rotate backwards. They have not yet discovered why Venus spins backwards
Describe the detection technique used by astronomers, Radial Velocity Method/Doppler Effect
Astronomers look at the stellar spectrum from low-altitude, periodic variations in the radial velocity of the parent stars produced by the gravity of the planet (Doppler "Wobble"). It is more likely to detect massive planets orbiting close to their stars using this method.
Be able to recognize and apply the following equation
Average Density = Mass / Volume
How do astronomers overcome the difficulties of finding exoplanets?
Because of the difficulties, astronomers realized that indirect methods must be used to discover exoplanets. Astronomers also chose to study nearby stars that are similar to our Sun (closer than 100 ly away).
Describe Neptune's magnetic field
Comparable in strength to Earth's magnetic field
What does it mean when it is said that Earth is in the "habitable" zone?
Earth is considered to be the "Goldilocks of Planets" because it is perfect distance from the Sun in order to sustain life. This allows for Earth to have water that is not all steam and not all ice. Astronomers search for exoplanets in hopes of discovering live beyond Earth
What are Exoplanets?
Exoplanets are planets outside of our solar system
List and describe Jupiter's Galilean Satellites.
Io -about the same size as earth -active volcanoes that change it surface continually -sulfur components coat its surface with a variety of colors -energy to melt the interior rock into lava must come from tidal effects due to Jupiter and other Galilean satellites Europa -about the same size as earth -cracked icy crust is reminiscent of Earth's polar ice -may be liquid water ocean dozens of km thick beneath a few km of ice Ganymede -about the size of Mercury -low density and probably have significant amounts of water/ice inside interior -has varied surface with old cratered sections Callisto -about the size of Mercury -low density and probably have significant amounts of water/ice inside interior -surface is covered with ancient craters -there has been little geological activity for about the past 4 billion years
Describe Titan's atmosphere.
It consists of mainly nitrogen gas. The surface pressure is about 1.5 bar. About 10% of its atmosphere consists of methane and other hydrocarbons. In 2005, Huygens probe separated from the Cassini probe and made a soft landing on the surface of Titan and radioed back images. The rounded rocks have been smoothed by flows of liquid methane and ethane in streams
What is Pluto?
Its status has long been controversial due to its small size and mass, and its odd orbit. The discovery of smaller objects called "Kuiper Belt Objects" (KBO's) also orbiting beyond Neptune's orbit showed the need to re-classify it as a dwarf planet based on the definition established by the International Astronomical Union on Aug. 24, 2006
Which planet is Saturn's very similar to?
Jupiter
Which of the Jovian Planets is referred to as the "King of the Planets"?
Jupiter, because of its large diameter and mass. It also has four huge satellites: Ganymede, Callisto, Io, and Europa
Describe the atmosphere on Uranus
Made up of mostly hydrogen. Its atmosphere is featureless, but blue (due to trace amounts of methane in atmosphere). The atmosphere of Uranus is very gaseous.
Which is the planet that is most studied by astronomers?
Mars
Compare the axial tilt of Mars to that of Earth's
Mars has a similar axial to Earth's, at 25.2 degrees. Seasons on Mars are much more severe and last a longer period of time
Be able to list the 8 major planets from the Sun
Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune
What are meteors?
Meteors can be seen on any clear night, but in small numbers. But, there are specific dates during the year when meteor "showers" occur. Meteor showers are named after the constellation nearest the point in the sky from which they seem to come - the "radiant" of the shower. Some showers have a consistently large numbers of meteors each year. A good one is the Perseid meteor shower in early August. Some meteoroids are large enough, or cohesive enough, to survive the ablation stage and end up on the ground as meteorites
What is the name of Uranus's major satellite? describe it
Miranda is the smallest and innermost of Uranus's satellites. Its orbit is perpendicular to the ecliptic and so it shares Uranus's extreme seasonal cycle. It is ~300 miles across. Miranda's surface may be mostly water and ice; strange mixture of surface types. Miranda has a sheer cliff that is about 20 km (10 miles) tall
Where do most asteroids orbit?
Most asteroids are confined to the "main belt", but the Centaur group has orbits that go beyond that of Jupiter. The Apollo group ("Earth-crossers") has perihelia inside Earth's orbit
What are Asteroids? Where do they orbit? When was the first asteroid discovered? What was it named? How many asteroids have been discovered?
Most of these rocky objects orbit in the "main belt" between the orbits of Mars and Jupiter. The first asteroid was discovered in 1801 and given the mythological name "Ceres" by its discoverer. More than 500,000 asteroids have since been discovered. Many more are thought to exist
How is the Astrometric Method (Wavy "Proper Motion" of the Stars) using as a detection technique by astronomers?
Nearby stars could be tugged back and forth by a massive object/planet. Astronomers look at its track across the sky as a way to show the existence of an object orbiting the star
Describe Neptunes interior
Neptune is considered a "ice giant". It consists of a rocky core, a highly compressed water "inner mantle", and a liquid hydrogen/helium "outer mantle"
What previously known planet was re-classified as a Dwarf Planet?
Pluto
What are 2 examples of Dwarf Planets?
Pluto and Ceres
Why is Pluto not considered to be part of the Jovian Planets anymore?
Pluto has been re-classified as a Dwarf Planet because of its very small size and mass compared to the rest of the 8 major planets. Its orbit is also not along the lines of the other planets as well
What are some examples of the inhabitants of the Kuiper Belt?
Pluto is considered a KBO, but it is only the second largest in diameter. Few asteroids stray from the main belt.
What is Earth's atmosphere composed of?
Primordial -CO2, H20, N2, and other Current -78% N2, 21% O2, traces of CO2, and others
How was the age of the solar system determined?
Radioactive dating of rock sample from the Earth, Moon, and meteorites have made it possible for scientists to determine the formation of the solar system
Which Jovian Planet would float in water if you were to find a bathtub big enough to fit it in?
Saturn, it has an average density of 0.7 gm/cm3, which is lower than the density of water and would allow Saturn to float on top of water
What are Small Solar System Bodies? Give examples
Small Solar System Bodies (SSSB) are the tiniest remnants of the solar system formation process. Some examples are smaller asteroids, comets, satellites of planets, and meteroroids
What is a "Martian Day"?
Sol
How are Stellar Transits used as a detection technique by astronomers?
Some exoplanets will have orbits whose planes are in our line of sight of the star. The exoplanet will periodically pass in from of, or transit, its star. Large diameter exoplanets are more likely to produce decreased brightness of its parent star.
How is direct imaging used as a detection technique by astronomers?
Technology now exists that can directly image an exoplanet in a wide orbit of apparent star relatively close to us
Be able to compare the following properties of the Terrestrial and Jovian Planets: average density, moons/satellites, rings, atmosphere, and rotation rate
Terrestrial Planets: -have high average densities -have few moons/satellites -have no rings -have an atmosphere described as "thin" -have a rotation rate that would be described as "slow" Jovian Planets: -have low average densities -have many moons/satellites -all four of the Jovian planets have rings -have an atmosphere described as "thick" -have a rotation rate that would be described as "fast"
What are the two distinct types of planets?
Terrestrial and Jovian
What is the largest visible white and brown in Jupiter's atmosphere? What is it believed to be?
The Great Red Spot is believed to be a huge hurricane-like storm on Jupiter
Describe the origin of the comets
The comets are believed to come from 2 resevoirs; the Ort Cloud and the Kuiper Belt. The Oort Cloud is thought to be roughly spherical in shape, centered on the Sun. It may contain billions of comet nuclei and reaches out to ~50,000 AU. The Kuiper Belt is an annulus extending from beyond Neptune's orbit (30 AU) to ~ 500 AU
According to the theory of the formation of the solar system, how long ago did our solar system form?
The solar system is estimated to have formed about 4.6 billion years ago.The theory of the formation of the Sun dates back to about the same time.
What is the Solar Nebula Theory? Explain and describe.
The universe began in an extremely hot and dense state about 14 billion years ago. After a few minutes, the temperature had dropped low enough for matter to form from energy. Essentially, only hydrogen and helium were produced during the "cool down" period. About 9 billion years later, the Sun and the planets formed, at about the same time, from material in an interstellar cloud. Small amounts of "heavier" elements must have been present from past supernova explosions. These elements were produced in the cores of stars that became supernova explosions. After being compressed, probably another nearby supernova explosion, the solar nebula began gravitational contraction. During this process, spinning nebula flattened in to a disk with a central concentration. This central concentration is referred to as the protosun. Gravitational contraction of the protosun released energy to heat it to a temperature that was about 10 million degrees K, at which it fuses. Meanwhile, the gas, ice, and dust in the disk slowly accreted to produce the planets. The inner part of the disk was warmed by radiation from the protosun. Only rocky and metallic particles were left behind. Beyond the snow line (or frost line), gasses and icy particles were also present.
How are asteroids given their names?
They are first given temporary names, like 2006 SQ 226, and later assigned names, usually chosen by the discoverer. The sequence number in order of discovery precedes the given name: 1) Ceres, 2) Pallas, 3) Juno, 4) Vest...
What are some common results of moving plate tectonics?
This movement often leads to earthquakes, volcanoes, mid-ocean rifts, and the recycling of the crust
What are two of Saturn's major satellites?
Titan and Enceladus
What is the name of Neptune's major satellite? Describe it
Triton. the largest moon of Neptune. This is the only moon in the solar system with a retrograde orbit. It is about 2,700km (1,700 miles) in diameter, but it has low pressure. Triton's surface is composed of mostly frozen nitrogen and a mostly water/ice crust. It has an ice mantle and a substantial core of rock and metal. It's atmosphere consists of mainly nitrogen.
What is notable exoplanet system discovery that was mentioned in class?
Upsilon Andromedae Three planets have been discovered in this system
What two Jovian Planets are considered the "twins"?
Uranus and Neptune, although they are not completely identical
Describe the ring system of Uranus
Uranus has a system of rings that are intermediate in complexity. 13 rings have been discovered that are composed of mostly materials that are dust-like
Give a description of Halley's Comet
Usually, comets are named for their discoverer(s), like Comet Hale-Bopp, which was easily visible to the unabided eye in March 1997. Edmund Halley did not discover the comet that bears his name; rather he was the first to predict that some comets make return trips to the inner solar system. When the comet made its predicted return in 1759 (after Halley's death), it was named in his honor. Comet orbits are quite different than the planets' (Many have high eccentricity, retrograde orbits, with steep inclination angles to the ecliptic). We now know that Halley's Comet has been seen at every perihelion passage since about 238 BC. It apparition in 1985-1986 was one of the poorest ever recorded. When it returns in 2061, it should again put on a great show. Studies show that the comet dust contains amino acids, such as those found in living organisms on Earth
What planet is considered Earth's "twin"?
Venus
What two Terrestrial Planets are considered the "twins"?
Venus and Earth, although they are not completely indentical
Which two planets rotate in retrograde motion (spin backwards)?
Venus and Uranus
Describe the surface of Venus.
Venus has a global perpetual cloud cover, so astronomers can use radar to study its surface. The radio waves pass through clouds and return signals to tell what the surface looks like. About 80% of Venus's surface is gently rolling plains with ~1,600 volcanoes/volcanic features. The U.S. Magellan probe used radar to map the entire surface of Venus. It showed that there were volcanic features with few impact craters. The U.S. and the Soviet Union have landed probes on Venus. The Russian probe Venera 13 revealed flat, angular rocks of probable volcanic origin on the surface of Venus before succumbing to the heat.
What are meteoroids?
Very small particles of solid debris orbiting the Sun are called meteoroids. Some of these have orbits that eventually intersect the Earth's. If a meteoroids enters the atmosphere at high speed it will "burn up" or "ablate" due to friction. This is known as a meteor or "shooting star". Most meteorites are associated with debris from the asteroid belt. But most meteor showers are associated with the debris left behind in the orbit of a comet. Meteorites are believed to be largely unaltered samples of the material that the solar system formed from some 4.6 billion years ago.
List Earth's atmospheric layers.
^ Thermosphere | Mesosphere | Stratosphere | Troposphere
What is the Kuiper Belt
a Torus of icy debris in the plane of the ecliptic, extending from about 30 to 500 AU from the Sun
What is the surface gravity on Mars?
a person standing on the surface of Mars would weigh 3/8 of what they would weigh if they were standing on the surface of Earth
As of 2015, how many exoplanets have been discovered?
about 2,000
What are examples of Small Solar System Bodies?
asteroids, meteors, meteorites, and meteoroids.
Describe Jupiter's atmosphere
clouds are drawn out into light and dark stripes that are parallel to the equator. Many white and brown ovals are visible
Describe the magnetic field of Uranus
comparable in strength to Earth's magnetic field. It is the planet with the greatest tilt in the solar system. It's axis points directly at the Sun. This causes very extreme seasonal cycles on Uranus.
Describe the interior of Uranus
considered an "ice giant". Uranus has a rocky core and a highly compressed water "inner mantle", as well as a liquid hydrogen/helium "outer mantle"
Describe Venus's atmosphere.
consists of mostly CO2 (96.5%). This carbon dioxide acts as a "greenhouse gas" to trap heat. Venus has the highest average temperature of all the planets in out solar system, which is about 890 degrees F. This surface pressure is 90 bars. This would be about the same amount of pressure that you would feel if you were ~3,000 feet deep in Earth's oceans.
What are the consequences of the Ozone Layer?
damage to the Ozone Layer results in increased solar UV damage to plants and animals (this is NOT the same thing as global warming)
What does the Ozone consist of?
depletion of 03 -Chlorofluorocarbons=CFC's
What is the Nice Model?
details of the Solar Nebula Theory that emerged from supercomputer simulations
How was the Kuiper Belt shaped?
doughnut shaped
How would you describe Mercury's atmosphere?
essentially no atmosphere - just low pressure
Describe the surface features of Mercury.
has no long maria even though it is covered with impact craters, like the Moon. There are smaller areas of solidified lava called "intercrater plains". There are also many sheer cliffs "scraps" that indicate the planet's crust shifted after craters formed. Scarps can be hundreds of miles long and greater than a mile high
When was Uranus discovered? Who is credited with the discovery? Who did he want to name his discovery after?
in 1781, William Herschel accidentally discovered Uranus while make star charts through a telescope. He wanted to name the newly discovered planet after the King of England, "Georgium Sidus"
When was Neptune discovered? Who is credited with the discovery?
in 1846, Adams/Leverrier/Galle, discovered Neptune based on a mathematical prediction. The credit to this discovery is controversial
When was Pluto discovered? Who is credited with this discovery?
in 1930, Clyde Tombaugh dicovered Pluto after a methodical photograph search
Is there any evidence for life on Mars?
in 1976, two Viking spacecrafts landed on the surface of Mars and tested the soil for life. No organic compounds were found at the sites that the soil was collected and tested. Two more rovers went to Mars, the Spirit rover and the Opportunity rover. In 2012, Curiosity landed on the surface of Mars. All three rovers found evidence of past liquid water on the surface of Mars. The last rover sent Mars is September of 2014 was the Maven rover. It was sent to study Mar's atmosphere.
Give examples of comets collisions with planets
in 1994 Comet Shoemake-Levy-9 broke into many pieces and collided with Jupiter. The impacts of these pieces released millions of tons of TNT in energy and left temporary scars
When was the first exoplanet discovered and who discovered it?
in 1995 by Mayor and Queioz it was named 51 Peg b and it is about 40 ly away in the direction of the constellation Pegasus
Give a description of Saturn's satellite Enceladus
in 2006, scientists discovered eruptions from this moon. They believe these eruptions to be water geysers
Describe Neptune atmosphere
it has a blue-green atmosphere. There are some visible features that include the Great Dark Spot and white methane cirrus clouds
What are Jupiter's rings made of?
it has not yet been discovered what these rings are made of
Describe Mercury's magnetic field.
it is only about as strong as 1% of Earth's magnetic field. The weak magnetic field is mainly due to Mercury's slow spin on its axis
What are the Terrestrial Planets composed of?
mostly made up of rocky, denser material
Does Earth's Moon have an atmosphere?
no
Is Pluto in the same plane as the rest of the 8 major planets?
no. this is part of the reason why it was re-classified as a dwarf planet
Collisions of asteroids with Earth?
over cosmic time intervals it is inevitable that asteroids will collide with Earth. The bigger the asteroid is, the greater the damage. There is evidence that a large asteroid struck Earth about 65 million years ago at Chicxulub, Mexico. Debris blown into the atmosphere may have darkened our planet for years, and may have contributed to the extinction of the dino's and other species. Some astronomers scan the sky every night looking for "Near Earth Objects" (NEO) that might eventually collide with Earth. In February 2013, an asteroid to be about 60 feet across, with a mass of 12 million kg entered the atmosphere over Chelyabinsk, Russia, producing a brilliant fireball and a shock wave that broke thousands of windows that injured about 1,500 people.
Describe Saturn's atmosphere.
similar to Jupiter's. Clouds are less distinct. Its atmosphere is made up of mostly hydrogen, but contains more hydrogen then Jupiter's
What is the Greenhouse Effect?
some incoming light is reflected back out into space by the clouds in Venus's atmosphere. The rest of the incoming sunlight strikes the surface of Venus. This gets absorbed by the surface and heats it up. Then infrared radiation gets emitted from the surface. Some of the infrared radiation gets reabsorbed and the rest of it escapes the atmosphere.
Explain the 2nd Mission to Mercury
the MESSENGER spacecraft flew by venus twice and Mercury once. Images were taken of the entire Caloris Basin (about 1,000 mile impact crater). MESSENGER spacecraft continues to study and orbit Mercury today.
Describe the interior of Mercury.
the core is made up of mostly iron. the planet is made up of mostly its core. The whole planet is smaller than just Earth's core.
What have astronomers concluded about previously discovered exoplanets and their period and orbit size?
the first exoplanet discovered were found quite close to their apparent stars. By Kepler's 3rd Law, this means that these exoplanets have short periods (if a=0.1AU, then P is equal to about 10 days). Amplitude of the Doppler shift tells the relative mass of an exoplanet. Massive exoplanets were the first to be discovered. With masses of up to several times Jupiter's, their proximity to their parent stars led to the term "hot Jupiters". As techniques have improved with time, lower mass exoplanets have been discovered, located farther from their parent star
What are the Terrestrial Planets?
the four inner planets: Mercury Venus Earth Mars
What are the Jovian Planets?
the four outer planets: Jupiter Saturn Uranus Neptune
What is the Ozone Layer?
the layer near the top of the Stratosphere
What is chemical differentiation?
the process in a fluid object where higher density material sinks to form a central core. Lower density material rises to form a crust with an intermediate mantle
What are plate tectonics?
the process of Earth's crustal development due to relative motion of about 16 plates that the crust is made up of
Magnetosphere
the region occupied by the magnetic field of the planet. It is produced by charged, fluid material in the interior of a (rapidly) rotation planet
What is the Oort Cloud?
the vast spherical distribution of icy debris extending out to about 50,000 AU from the Sun
What are the Jovian Planets composed of?
they are composed of gaseous material
What did leftover debris from the construction process lead to?
while solid debris had been sent to the inner solar system, icy debris propelled out beyond Neptune's orbit. This produced Kuiper's Belt
