Earth and Space Science Flashcards
How many known extrasolar planets exist as of 2008?
333
The solar system contains at least ____ dwarf planets
5 (Ceres, Pluto, makemake, haumea, Eris)
A small solar system body that orbits the sun and, when, close enough to the sun, exhibits a visible coma (atmosphere) or a tail
A comet
Loose collections of ice, dust, and small rocky particles measuring a few kilometers or tens of kilometers across.
Comet nuclei
Comets that are thought to originate in the Kuiper Belt, or associated scattered discs, which lie beyond the orbit of Neptune.
Short period comets
Comets that are believed to originate at a much greater distance from the sun, in a cloud (the Oort Cloud) consisting of debris left over from the condensation of the solar nebula.
Long period comets
They are sometimes called minor planets/planetoids, and are bodies–primarily the inner solar system–that are smaller than planets but larger than meteoroids, excluding comets
Asteroids
What is the difference between asteroids and comets?
Visual appearance: when discovered, comets show a perceptible coma while asteroids do not.
What is the distance from the earth to the sun?
The earth travels in orbit that is slightly oval (elliptical) so the distance ranges from 91.5 to 94.5 million miles
The degrees east or west of the prime meridian through Greenwich, England
Longitude
The degrees north or south of the equator
Latitude
What is the explanation to why we have seasons?
The seasons of the year are the consequence of the earths equatorial plane being tilted about 23 degrees from the orbital plane
In each hemisphere at noontime, the sun is near the zenith during _____, and low in the sky during ______.
In each hemisphere, at noontime, the sun is near the zenith during SUMMER, and low in the sky during WINTER
What is the distance between the moon and the earth?
237,000 miles
The phase of the moon when it is in conjunction with the sun and visible from earth, or shortly thereafter when it appears as a slender crescent.
New moon
The moon is less than one half illuminated by the sun but less than one quarter illuminated.
Waxing crescent
During this phase of the moon, fifty percent of it is illuminated and visible from the earth. It occurs after the Crescent phase and before the Waxing Gibbous phase.
First quarter (moon phase)
When the moon appears to be more than one half but not fully illuminated by direct sunlight. This phase happens when the moon is between 45 and 90 degree angle with respect to the earth and sun
Waxing Gibbous moon
The phase of the moon in which it is visible as a fully illuminated disk
Full moon
Moon phase that occurs when the moon appears to be more than one half illuminated (but not fully illuminated); when the moon is between a 90 and 135 degree angle with respect to the earth and sun.
Waning Gibbous moon
Darkens the moon as the earth passes between it and the sun, casting a shadow on the moon.
Lunar eclipse
Takes place when the moon passes between the earth and the sun, with the moon blocking the sunlight for about 2 minutes. (A total eclipse may only be seen from the small zone on the earth)
Solar eclipse
A huge ball of incandescent gases. It’s mass is more than 300,000 times that of the earth (it’s volume could engulf a million earths)
The sun
What are the two principal constituents of the sun?
The lightest elements, hydrogen and helium (gases undergoing nuclear fusion to heavier elements with the release of prodigious quantities of energy)
The sun’s atmosphere is divided into the ______________ with explosive prominences and the __________, a glowing halo only visible during a solar eclipse
Inner chromosphere; outer corona
Bodies similar to the sun but immensely distant
Stars
Astronomers have calculated the distance to many of the closest stars by measuring the __________, a slight shift in apparent position against the background of more distant stars as the earth travels around the sun
Parallax
Interstellar distances are described in ___________. ( the distance light travels in one year)
Light years. (The nearest star is 4 light years away!)
Huge systems of stars
Galaxies
Our galaxy. The sun is not in the center, rather in the outward perimeter, and is revolving around the galactic center.
The Milky Way
Galaxy that is about 20 million light years away
Andromeda
Stars of variable luminosity that serve as distance indicators (helps us know how far away others are)
Cephids
The spectra of distant objects display a _______, which is interpreted as meaning they are rapidly receding from us (given the rise of the Big Bang theory)
Red shift
A region of the earth that has uniform standard time (usually referred to as local time)
Time zone (standard and day light saving/summer)
Geometrically subdividing the earths spheroid into 24 lunes (wedge shaped sections), bordered by meridians, each 15 degrees of longitude apart. (15 degrees of longitude=1 hour of time)
Standard time zones
Earth reaches ________ (the point in its orbit closest to the sun) in January, and it reaches _________ (farthest from the sun) in July.
Peripehlion; aphelion
What are the two main types of planets?
Large low density gas giants, and smaller rocky terrestrials
These occur two times a year,me hen the tilt of the earths axis is oriented neither from nor to the sun, causing the sun to be located vertically above a point to the equator.
- at this time, night and day are equally long
- happens each year at two specific moments in time (not a whole day)
Equinoxes (Latin: aequus=equal, nox=long)
Occurs at the instant when the sun’s position in the sky is at its greatest angular distance on the other side of the equatorial plane from the observer’s hemisphere
Winter solstice
The science that describes and interprets the earth
Geology
Study of landforms
Geomorphology
The study of rocks
Petrology
The study of layered rocks
Stratigraphy
The study of fossils
Paleontology
Using the events of today to infer about the past
Uniformitarianism
One of three main rock types. Formed by deposition and consolidation of mineral and organic material and from precipitation of minerals from solution.
-covers 75-80% of earths land area
Sedimentary rock
What are some common examples of sedimentary rock?
Limestone, chalk, dolostone, sandstone, conglomerate, types of brecca, and shale
Type of rock that is formed by solidification of cooled magma (molten rock)
- over 700 types have been described
- have diverse properties depending on how they were formed
Igneous rocks
What are some common igneous rocks?
Plutonic: granite, gabbro
Volcanic: basalt, rhyolite
Rock type that is the result of the transformation of an existing rock type (the protolith) in a process called metamorphism, which means change in form.
- make up a large percentage of the earths crust
Metamorphic rock
Examples of metamorphic rock
Slate, marble, schist, quartzite
Natural chemical compounds that are the crystals that make up rocks
- each has a specific composition or narrow range of composition
Minerals
What are the most abundant minerals and how are they formed?
Quartz, olivine, augite; they are silicates, built from interlocking silicon and oxygen atoms
A landform that stretches above the surrounding land in a limited area, with a peak.
-generally steeper than a hill, no universally accepted standard of height (usually has an identifiable summit)
Mountain
Natural flow of water, usually freshwater, traveling toward an ocean, lake or another stream.
-a component of the water cycle
River
Take up about 1/3 of the earths land surface, have a large diurnal and seasonal temperature range, with high day time temperatures and low Night time temperatures (due to extremely low humidity)
Deserts
The decomposition of the earths rocks, soils, and their minerals through direct contact with the planets atmosphere.
-occurs in situ (no movement), and thus should not be confused with erosion
Weathering
Involves the movement of rocks and minerals by agents such as water, ice, wind, and gravity
Erosion
The breakdown of rocks and soils through direct contact with the atmospheric conditions such as heat, water, ice, and pressure
Physical weathering
Involves the direct effect of atmospheric chemicals of biologically produced chemicals in the breakdown of rocks, soils, and minerals
Chemical weathering
How erosion is increased by human land use
Poor land practices including deforestation, overgrazing, unmanaged construction activity, and road building
How improved land use practices can limit erosion
Using techniques such as terrace building, conservation tillage practices, and tree planting
Excessive erosion can cause damage by excessive loss of soil
The layers of sediment deposited in a quiet environment
-commonly very extensive laterally, and relatively thin vertically, like a blanket
Strata
Younger beds were originally deposited above older beds
Law of superposition
Traces of ancient life preserved in the strata as shells, footprints, and the like
Fossils
What lay in the earliest fossil rich beds?
Trilobites, early crab-like creatures that have been extinct for hundreds of millions of years
Represents interpretations from fossils and radioactivity. The earth is believed to be about 5.6 billion years old. Fossil records only show the last 11% of the worlds history
The geological time scale
Beginning: 70,000,000 ybp
Duration: 70,000,000 years
Characteristic life forms: mammals
Cenozoic era
Beginning: 225,000,000 ybp
Duration: 155,000,000 years
Characteristic life forms: reptiles
Mesozoic era
Beginning: 600,000,000 ybp
Duration: 375,000,000 years
Characteristic life forms: invertebrates
Paleozoic era
Beginning: 5,600,000,000 ybp
Duration: 5,000,000,000 years
Characteristic life forms: no life except algae
Precambrian era
About 31% of the earths mass, it is made up of liquid iron and nickel metals, melted by the extremely high temperature of the center of the earth (3,000 degrees Celsius)
The earth’s core
Around the liquid core is the largest zone of the planet (67%), of crystalline silicates, rich in magnesium, calcium, and iron.
-very hot and mainly solid, local melting go magma, and is source of volcanic eruptions
The earths mantle
Makes up less than 1% of the earth; above the mantle.
-thin zone, about 5-25 miles, contains the only rocks we can study
The earth’s crust
The result of forces within the earth, where temperature and pressure changes lead to instability
-particularly severe in organic zones
Earth movements
Zones that are characterized by volcanism, metamorphism, deformation, and uplift
Organic zones
The large scale motions of the earths lithosphere
Plate tectonics
The outermost part of the earths interior is made of the ________, comprising the crust and uppermost part of the mantle
Lithosphere
Below the lithosphere lies the _________, that has low viscosity and sheer strength and can flow like a liquid on geological time scales.
Asthenosphere
Three types of plate boundaries
1.) convergent or collision boundaries 2.) divergent or spreading boundaries 3.) transform boundaries
The lateral movement of the plates is typically at speeds of ____ to ____ mm annually
50 to 100 mm annually
An area of frequent earthquakes and volcanic eruptions encircling the basin of the Pacific Ocean
- a 40,000 km horse shoe shape
- 90% of all earthquakes, 80% largest earthquakes
- a direct result and consequence of plate tectonics
The pacific ring of fire
How mountains result from lithospheric plates
Compressional forces, isostatic uplift, and intrusion of igneous matter forces surface rock upward. Major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity
An opening, or rupture, in a planets surface or crust, allowing not molten rock, ash, and gases to escape from below the surface.
-are generally found where tectonic plates are diverging or converging
Volcanoes
The science of the atmosphere and weather
Meteorology
The amount of water vapor in the air depends on the prevailing _________ and the availability of ________
Temperature; water
Water transpired from plants and evaporated from the soil
Evapotranspiration
Condensed water vapor that falls to the earths surface. Mostly occurs as rain, but also can be snow, hail, fog drip, or sleet
Precipitation
The precipitation that is intercepted by plant foliage and eventually evaporates back into the atmosphere rather than falling to the ground
Canopy interception
Runoff produced by melting snow
Snowmelt
Variety of ways by which water moves across the land. Includes surface runoff and channel runoff. As it flows, the water may percolate to the ground, evaporate into the air, become stored in lakes or reservoirs, or be extracted for agricultural or other human uses.
Runoff
The movement of rainwater as it filters through soil and rocks into the ground, becoming groundwater
Percolation
The flow of water underground
Subsurface flow
The transformation of water from liquid to gas phases as it moves from the ground or bodies of water into the overlying atmosphere
Evaporation
The state change where a solid (ice or snow) changes directly to gas (water vapor)
Sublimation
The transformation of water vapor to liquid water droplets in the air, producing clouds of fog
Condensation
Almost all weather phenomena occur in the __________ (the lower part of the atmosphere)
Troposphere
Weather occurs primarily due to _________ (temperature and moisture) differences between one location and another
Density. Differences can occur due to the angle of the sun at any particular spot, which varies by latitude from the tropics.
The farther from the tropics you are positioned, the _______ the angle of the sun.
Lower (causes these locations to be cooler)
Surface temperature differences cause ________ differences
Pressure. A hot surface heats the air above it and the air expands, lowering the air pressure and its density
How is wind created?
The horizontal pressure gradient accelerates the air from high to low, creating wind.
The motive force behind land breezes and sea breezes (also known as off shore winds)
Differential heating
Land absorbs and radiates heat _______ than water, but water releases heat over a long period of time.
Faster
In locations where sea and land meet, heat absorbed over the day will be radiated _______ quickly by the land at night, _______ the air.
More; cooling
