Chapter 1 Flashcards
something that answers the question “why and how” and it has been tested repeatedly and has so far always been true.
Theory
scientific study of the physical universe (origin, evolution, fate)
Cosmology
science of celestial bodies and phenomena (characteristics, position, motion, composition)
Astronomy
It states that the universe began as a hot and infinitely dense point. This tiny “singularity” violently exploded, and from that explosion, all matter, energy, space, and time were created.
The big bang theory
Proofs of big bag
Hubble’s law
Cosmic microwave background (CMB) radiation
Abundance of light elements
Galaxies have been observed to be moving from the Earth at speeds that are proportional to their distance.
• Supports the expansion of the universe and suggests that it was once compacted
Hubble’s law
• Pervades (spread through) ALL the known universe.
• The CMB is the evidence of the theory’s statement that if the universe was extremely hot and extremely small at one point in time, then there should be evidence of this extreme temperature across the universe
Cosmic microwave background (CMB) radiation
•The sheer volume of light elements, Hydrogen and Helium in the observable universe.
•Supports the model since these are the first elements to form in the high- energy environment during and shortly after the Big Bang.
Abundance of light elements
Expansion implies that at some point the universe was smaller
… if it is expanding, the universe must have been smaller
Streak of light seen when a meteoroid heats up in the atmosphere
Meteor
Rocky body smaller than a planet that orbits the sun
Asteroid
Meteor fragment that reaches the ground
Meteorite
Icy body that releases gases as it orbits the sun
Comet
Rocky or metallic fragment of an asteroid, comet, or planet
Meteoroid
Models of the universe
Geocentric Model by Claudius Ptolemy
Heliocentric Model by Nicolaus Copernicus
Earth-centered
• The sun, moon, stars and the 5 planets (Mercury, Venus, Mars, Jupiter, and Saturn) moved around the Earth.
• Planets moved with respect to fixed stars, changing brightness, changing speed, and having retrograde motion.
Geocentric model by Claudius Ptolemy
Sun-centered
• heliocentrism, a cosmological model in which the Sun is assumed to lie at or near a central point.
Heliocentric Model by Nicolaus Cupernicus
Theories on the Origin of the Solar System build up of the idea on the ———
Angular Momentum
Formed about 4.5 billion years ago
A dense cloud of interstellar gas and dust from a nearby exploding star (supernova) eventually formed a solar nebula – a spinning, swirling disk of material
Solar Nebula
• Star passed closed enough to the sun, creating huge tides and causing materials to be ejected.
• These smaller masses quickly cooled and became numerous planetesimals. • The accretion of planetesimals created the larger bodies or protoplanets.
Planetesimal theory
• A massive star passed by the Sun, drawing from it a tidal filament.
• The gravitationally unstable filament broke up with each condensation forming a protoplanet.
• A dualistic theory
Tidal theory
The dense area of the Nebula and the gaseous matter surrounding it ceased to rotate uniformly
• Under the influence of turbulence and tidal action, the nebula broke into whirlpools of gas within a rotating mass called protoplanets.
Protoplanet Theory
—— drive the Earth’s subsystems. It is through these cycles that earth materials are recycled and replenish.
Biogeochemical cycles
Earth’s four Spheres
Atmosphere
Hydrosphere
Biosphere
Lithosphere/Geosphere
•Largest of the four spheres
•Comprises the solid portion of the Earth
•Extends 6,400 km from the surface down to the core
Geosphere
Layers of the geosphere
Crust
Mantle
Core
a cold, thin, brittle outer shell made of rock; less than 1% of Earth by mass
• Oceanic crust
• Continental crust
Crust
hot, ultramafic rock; it represents about 68% of Earth’s mass
• Scientists discovered that mantle is made of rock based on evidence from seismic waves, heat flow and meteorites
Mantle
dense metallic (mostly composed of iron); makes about 31% of the Earth
Core
•Accounts for more than 70% of the Earth’s surface area
•Not limited to the water we see on the surface; groundwater is part of the hydrosphere cycle
Hydrosphere
Layer of gaseous envelope that surrounds the planet on the surface and extends thinly into space
Atmosphere
Layers of atmosphere
Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
contains mainly oxygen and hydrogen
Exosphere
very hot & high amount of x-rays and UV radiation
Thermosphere
serves as a shield for meteorites
Mesosphere
contains much of the ozone
Stratosphere
lowest part and the part we live in
Troposphere
A set of layers of gases that blankets the planet held by the planet’s gravity. It is consisted of 78% nitrogen, 20.95% oxygen, 0.93% argon and 0.04% water vapor including all other gases. Different layers of the atmosphere include the troposphere, stratosphere, mesosphere and thermosphere.
Atmosphere
It is the liquid component of the Earth including oceans, glacial waters, and freshwater bodies that covers 70% of the earth’s surface; 98% of the water on Earth is saltwater.
Hydrosphere
•Includes all forms of life on Earth
•Includes organisms found in the deepest parts of the oceans and highest parts of the atmosphere
Biosphere
It is the solid sphere of the earth. This is where geologic processes such as volcanism and orogenesis (mountain building) take place. The lithosphere is a part of the geosphere that is composed of the solid, outermost part of the planet.
Geosphere
This is the living sphere of the earth. It is the totality of all the ecosystems in the whole planet. It compels us to interact with other living organisms with the influence of the abiotic factors in the system.
Biosphere
