P1 Keywords Flashcards
(29 cards)
Galaxy
a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
universe
The Universe is all of time and space and its contents. It includes planets, moons, minor planets, stars, galaxies, the contents of intergalactic space, and all matter and energy.
Crust
the outermost layer of a planet composed of a great variety of igneous, metamorphic, and sedimentary rocks
Mantle
the part of the earth between the core and the the crust and is made up of magma and rock.
Core
a liquid layer made of iron and nickel. This is above the Earth’s solid inner core and below the mantle.
Light pollution
brightening of the night sky which has a disruptive effect on natural cycles and inhibits the observation of stars and planets.
Asteroid
A small rocky body orbiting the sun
Comet
celestial object consisting of a nucleus of ice and dust and, when near the sun, a ‘tail’ of gas and dust particles pointing away from the sun.
Fusion
the process or result of joining two or more things together to form a single entity.
Dwarf Planet
a celestial body resembling a small planet but lacking certain technical criteria that are required for it to be classed as a planet.
Light-Year
a unit of astronomical distance equivalent to the distance that light travels in one year, which is 9.4607 × 1012 km (nearly 6 million million miles).
Parallax
the effect whereby the position or direction of an object appears to differ when viewed from different positions, e.g. through the viewfinder and the lens of a camera.
nebula
a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.
big bang
the cosmic explosion that marked the beginning of the universe
Redshift
the displacement of spectral lines towards longer wavelengths (the red end of the spectrum) in radiation from distant galaxies and celestial objects; used to prove that the universe is expanding.
Erosion
the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc.
Continental Drift
he gradual movement of the continents across the earth’s surface through geological time.
Oceanic ridge
any section of the narrow, largely continuous range of submarine mountains that extends into all the major oceans and at which new oceanic lithosphere is created by the rise of magma from the earth’s interior.
Seafloor Spreading
Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge; this helps explain continental drift in the theory of plate tectonics.
tectonic plates
the lithosphere of the earth is divided into a small number of plates which float on and travel independently over the mantle and much of the earth’s seismic activity occurs at the boundaries of these plates.
Rock Cycle
an idealized cycle of processes undergone by rocks in the earth’s crust, involving igneous intrusion, uplift, erosion, transportation, deposition as sedimentary rock, metamorphism, and further melting and igneous intrusion.
Mountain Chain
a geographic area containing numerous geologically related mountains.
P - waves
They are longitudinal waves which mean the vibrations are along the same direction as the direction of travel. They can travel through both solids and liquids.
S - waves
Are the secondary waves and can only travel through solids.They are transverse waves which mean the vibrations are at right angles to the direction of travel. Other examples of transverse waves include light waves and water waves.
