Science Lecture Notes Review

Flashcards to review key vocabulary and concepts from a Science lecture on astronomy, physics, and related topics.

Science

The methodical study of natural phenomena.

Social sciences

Deal with human and social relationships, and include the disciplines of anthropology, economics, history, political science, psychology, and sociology.

Natural sciences

Deal with the physical world and include biology, physics, chemistry, geology, and astronomy.

Astronomy

Study of planets and their adornments, stars and star systems, nebulae and galaxies, and evolution of the universe

Astrophysics

Applications of physics laws and theories to astronomical objects and observations

Cosmology

Science dealing with the evolution of the universe

Astrobiology

Interdisciplinary study of life in the universe

Universe

Totality of all energy, matter, time, and space

Hypothesis

Objective proposition based on verifiable data that describes natural phenomena and is capable of being proven false by testing.

Geocentric models

Models of heavenly motion where Earth was at the center.

Ptolemaic models

Earth-centered models of planetary motion

Heliocentric models

Models of the universe where Sun was at the center.

Matter

A substance or object that occupies space and has mass.

Solid

Object of definite volume and definite shape

Liquid

Substance of definite volume and variable shape

Gas

Substance of variable volume and variable shape

Plasma

High temperature gas of electrons and ions

Ion

Atom that has an excess of electrons (negative ion) or deficit of electrons (positive ion) compared to the electrically neutral atom.

Phase change/transition

The change from one state of matter to another

Fluid

Substance of indefinite shape that flows easily.

Temperature

Measure of hotness or coldness; a measure of the average kinetic energy of atoms or molecules in an object/substance

Kinetic energy

Energy of motion, manifested by the movement of an object, substance, or particle

Force

Push or pull.

Energy

Property to cause motion.

Mass

Quantity of matter

Law of conservation of energy

Energy cannot be created or destroyed, only transformed from one form to another

Kelvin scale

A thermodynamic temperature scale because it has a meaningful (i.e., natural) zero.

Absolute zero

The temperature at which all classical motion ceases to exist.

Kepler’s Third Law

Distance of the planet from the Sun cubed is proportional to the orbital period of planet squared

Star

Glowing ball of gas and plasma that derives its energy from nuclear fusion

Dwarf planet

World that orbits a star and is spherical shape, but has not cleared its neighborhood of debris

Moon

Large natural satellite that orbits a planet

Satellite

Smaller object that orbits around a larger object

Asteroid

Small rocky object (typically hundreds of meters to a thousand kilometers in size) that orbits the Sun

Comet

Small icy and rocky object (typically hundreds of meters to a thousand kilometers in size) that orbits the Sun

Kuiper belt

Disk-shaped region that extends from 30 au (Neptune’s orbital radius) to about 100 au

Oort cloud

Huge spherical region surrounding the Sun, extending out to 50,000 to 100,000 au

Peer review

Evaluation of scholarly or professional work by experts (peers) in the same field

Matter

Physical substance that has rest mass and occupies space (i.e., has a volume)

Mass

Quantity of matter; quantitative measure of inertia

Inertia

Tendency of an object to resist a change in its state of motion

Isotope

Atom that is the same chemical element, i.e., has the same atomic number, but a different number of neutrons

Proton-proton chain

Series of three nuclear reactions that convert four H nuclei into a He nucleus and other particles with an energy release of about 27 MeV per reaction

Telescope

Optical instrument that makes distant objects appear closer, and therefore larger than would be seen with the naked eye.

Light

Electromagnetic radiation

Planck spectrum

Spectrum (I.e., all wavelengths) of light emitted by a blackbody per unit area per unit time

Black body

Idealized physical object that absorbs all incident light, regardless of wavelength and incidence angle

Intensity (of light)

Amount of radiated energy per area per time

Power (P)

Energy per time

Wave speed (v)

How fast a wave disturbance propagates

Light-year (ly)

Distance that light travels in one year.

Wave-particle duality

Light and matter exhibit properties of both waves and particles.

Planck spectrum

Continuous distribution of radiated light by an object that depends only on its temperature

Spectroscopy

Branch of science concerned with spectra produced when matter and light interact

Doppler Effect

Shifting of wavelength (and therefore frequency) of sound or light as a result of relative motion between wave source and observer

Light-year (ly)

Distance that light travels in one year.

Heavy element (in astronomy)

Any element more massive than helium (so, any element that is not H or He)

Nebular hypotheses

Star forms from a collapsing cloud of gas and dust

Nebula

Cloud of interstellar gas and dust, generally seen as illuminated by stars (bright nebula) or as a dark (often black) region of space against a brighter background (dark nebula)

Exoplanet

A planet orbiting a star other than Sun

Luminosity

Total energy output per time from a radiating object

Solar constant

The amount of solar energy reaching the Earth’s upper atmosphere per unit area per unit time

Solar wind

Stream of energetic charged particles moving away from the Sun

Magnetic domain

Region of space where individual ‘atomic magnets’ are all aligned (i.e., pointing) in the same direction

Granulation (on Sun)

Bubbling pattern visible in the photosphere, produced by underlying convection

Sunspot

Earth-sized dark region on the surface of Sun (this region appears darker because it is cooler in temperature, about 4000 K)

Prominence

Loop of gas ejected from an active region of the solar surface which then moves through the inner part of the corona under the influence of Sun’s magnetic field

Coronal hole

Large, low density (about 10 times lower than average) region where gas streams freely from Sun, escaping into space

Coronal mass ejection (or CME)

Giant cloud of solar plasma filled with magnetic field lines that are blown away from Sun during strong, long-duration solar flares

Protoplanetary disk

A disk of material surrounding a young star (or protostar) from which planets may eventually form

Geological process

Process responsible for the surface features of planets, dwarf planets, moons, asteroids, and comets

Obliquity (axis tilt)

Inclination of a body’s equator to its orbital plane

Atmosphere

Gravitationally bound gaseous envelope that surrounds a planet, moon, or star

Comet

Cosmic snowball of ices, rocks, and dust

Meteorite

Rock from space that lands on Earth

Eclipse

The passing of one celestial object through the shadow of another

Spin-orbit resonance

A relationship between the rotation and orbital periods of an object such that the ratio of their periods can be expressed as a ratio of simple integers

Belt (on a jovian planet)

Dark band of low-pressure sinking gas that encircles a planet at a nearly constant latitude

Zone (on a jovian planet)

Bright band of high-pressure rising gas that encircles a planet at a nearly constant latitude

Dwarf planet

An object that satisfies the first two criteria to be a planet, but not the third

Asteroid

Difficult to detect because they (i) do not radiate light like stars and (ii) are usually too small to reflect appreciable amounts of sunlight (like planets and moons)

Asteroid

Object relatively small, rocky or metallic object that orbits a star

Asteroid belt

Disk-shaped region between the orbital paths of Mars and Jupiter where most asteroids orbit

Comets and meteorites

Area with Comets a body of ice and rock typically orbiting the Sun in a highly eccentric orbit

Short-period comet

Body a comet that a Kuiper Belt short-period comet had originated in and has an orbital period is less than 200 years

Long-period comet

A body spherical -Oort cloud long period and had originated in object had in has orbital period from 200 years to millions of years

Coma of a comet

An enveloping cloud surface of comas near suns that that a passes .

Ion or Plasma tail of Comet.

Coma ion ionized and that is blown

Dust tail of comet.

Sun radiation dust comas of nucleas

Meteor showers.

Trail high debris comet, heating cause glowing the sky.

Meteroids

Rock with a Sun

Meteor

Enter earth atmosphere with high high speed heating fireball

Meteorites

Stricter of rock plant earth and lunars

Main belt asteroids

Asteroids that orbit between the orbital paths of Mars and Jupiter

Trojan asteroids

A collection of two groups of asteroids that travel with Jupiter, one leading Jupiter in its orbit and the other following

Earth-crossing asteroids (ECAs)

Asteroids whose paths cross Earth’s orbit, due to their highly elliptical orbits

Near-Earth Object (NEO)

An asteroid, comet, or large meteoroid whose orbit intersects Earth’s orbit

Meteoroid

A rock orbiting the Sun and ranging in size from a grain of sand to a boulder

Main belt asteroids

Asteroids that orbit between the orbital paths of Mars and Jupiter

Kuiper belt

Comets and that were dirt