Astronomy Test

Scientific Method

the steps scientists use to create explanations based on the evidence they gather

Theoretical Model

Theories are formulated to explain, predict, and understand phenomena and, in many cases, to challenge and extend existing knowledge within the limits of critical bounding assumptions. The theoretical framework is the structure that can hold or support a

Constellations

a group of stars forming a recognizable pattern that is traditionally named after its apparent form or identified with a mythological figure. Modern astronomers divide the sky into eighty-eight constellations with defined boundaries.
a group or cluster of

Celestial Sphere

an imaginary sphere of which the observer is the center and on which all celestial objects are considered to lie.

Celestial Poles

the point on the celestial sphere directly above either of the earth's geographic poles, around which the stars and planets appear to rotate during the course of the night. The north celestial pole is currently within one degree of the star Polaris

Celestial Equator

the projection into space of the earth's equator; an imaginary circle equidistant from the celestial poles.

Rotation vs. Revolution

Rotation is when a planet or moon turns all the way around or spins on its axis one time. The axis of rotation is an imaginary line going from the north pole to the south pole. When a planet or moon travels once around an object this is considered a revol

Solar vs. sidereal day

A solar day is the time it takes for the Earth to rotate about its axis so that the Sun appears in the same position in the sky. The sidereal day is ~4 minutes shorter than the solar day. The sidereal day is the time it takes for the Earth to complete one

Solstices

either of the two times in the year, the summer solstice and the winter solstice, when the sun reaches its highest or lowest point in the sky at noon, marked by the longest and shortest days.

Equinoxes

the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).

Precession

the slow movement of the axis of a spinning body around another axis due to a torque (such as gravitational influence) acting to change the direction of the first axis. It is seen in the circle slowly traced out by the pole of a spinning gyroscope.

Lunar Phases

The lunar phase or phase of the moon is the shape of the illuminated (sunlit) portion of the Moon as seen by an observer on Earth. The lunar phases change cyclically as the Moon orbits the Earth, according to the changing positions of the Moon and Sun rel

Eclipses

An eclipse is the result of either an occultation (completely hidden) or a transit (partially hidden). The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the

Geocentric

having or representing the earth as the center, as in former astronomical systems.
ASTRONOMY
measured from or considered in relation to the center of the earth.

Heliocentric

having or representing the sun as the center, as in the accepted astronomical model of the solar system.
ASTRONOMY
measured from or considered in relation to the center of the sun.

Ellipses

a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points (the foci) is constant, or resulting when a cone is cut by an oblique plane that does not intersect the base.

Focus

a central point, as of attraction, attention, or activity: The need to prevent a nuclear war became the focus of all diplomatic efforts. 2. Physics. a point at which rays of light, heat, or other radiation meet after being refracted or reflected.

Semimajor Axis

The semi-major axis is one half of the major axis, and thus runs from the centre, through a focus, and to the perimeter. Essentially, it is the radius of an orbit at the orbit's two most distant points. For the special case of a circle, the semi-major axi

Period

The orbital period is the time a given astronomical object takes to complete one orbit around another object, and applies in astronomy usually to planets or asteroids orbiting the Sun, moons orbiting planets, exoplanets orbiting other stars, or binary sta

astronomical unit

a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun.

Acceleration

a vehicle's capacity to gain speed within a short time.
increase in the rate or speed of something.

Mass

mass definition. In physics, the property of matter that measures its resistance to acceleration. Roughly, the mass of an object is a measure of the number of atoms in it. The basic unit of measurement for mass is the kilogram. (See Newton's laws of motio

Inertia

A property of matter by which it continues in its existing state of rest or uniform motion ina straight line, unless that state is changed by an external force

Gravity

the force that attracts a body toward the center of the earth, or toward any other physical body having mass. For most purposes Newton's laws of gravity apply, with minor modifications to take the general theory of relativity into account.

inverse-square law

The inverse-square law, in physics, is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.

wavelength

the distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave

frequency

1.
the rate at which something occurs or is repeated over a particular period of time or in a given sample.
"shops have closed with increasing frequency during the period"
2.
the rate at which a vibration occurs that constitutes a wave, either in a materi

amplitude

1.
PHYSICS
the maximum extent of a vibration or oscillation, measured from the position of equilibrium.
2.
ASTRONOMY
the angular distance of a celestial object from the true east or west point of the horizon at rising or setting.

electric/magnetic fields

a field of force that consists of both electric and magnetic components, resulting from the motion of an electric charge and containing a definite amount of electromagnetic energy.

Diffraction

the process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced.

Electromagnetic spectrum

electromagnetic radiation is classified by wavelength into radio wave, microwave, terahertz (or sub-millimeter) radiation, infrared, the visible region that is perceived as light, ultraviolet, X-rays and gamma rays

Radio Waves

Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light

infrared radiation

Infrared radiation is a type of electromagnetic radiation, as are radio waves, ultraviolet radiation, X-rays and microwaves.

visible light

Visible light is a form of electromagnetic (EM) radiation, as are radio waves, infrared radiation, ultraviolet radiation, X-rays and microwaves. Generally, visible light is defined as the wavelengths that are visible to most human eyes'

ultraviolet radiation

Ultraviolet (UV) radiation is part of the electromagnetic spectrum emitted by the sun

X-rays

1.
an electromagnetic wave of high energy and very short wavelength, which is able to pass through many materials opaque to light.
2.
a photographic or digital image of the internal composition of something, especially a part of the body, produced by X-ra

Gamma rays

Gamma rays have the smallest wavelengths and the most energy of any wave in the electromagnetic spectrum. They are produced by the hottest and most energetic objects in the universe, such as neutron stars and pulsars, supernova explosions, and regions aro

Temperature

the degree or intensity of heat present in a substance or object, especially as expressed according to a comparative scale and shown by a thermometer or perceived by touch.

blackbody curve

A blackbody (sometimes spelled "black body") is a theoretically ideal radiator and absorber of energy at all electromagnetic wavelength s. The term comes from the fact that a cold blackbody appears visually black. The energy emitted by a blackbody is call

Doppler Effect

The Doppler effect (or the Doppler shift) is the change in frequency or wavelength of a wave for an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842.

Scientific Method 5 Steps
cumulative/progressive driection

Step 1: Ask a question or identify a problem. ...
Step 2: Background research. ...
Step 3: Form a hypothesis. ...
Step 4: Experiment and observe. ...
Step 5: Draw a conclusion.

Arrange the structure of the universe in order of Size

1)Planet, 2)star, 3)solar system, 4)open cluster, 5)galaxy, 6)cluster of galaxies, 7)supercluster

Methods how astronomers use constellations and angular measure to determine positions in the sky

Parallax is the visual effect produced when, as an observer moves, nearby objects appear to shift position relative to more-distant objects. This common event is easily reproduced; hold your finger out at arm's length, and look at your fingertip first wit

Explain the changing motion of the sun, moon, and planets with respect to the background stars

The orbital motion

Understand the relationship between the Earth's axial tilt and our changing seasons

Earth has seasons because our planet's axis of rotation is tilted at an angle of 23.5 degrees relative to our orbital plane - the plane of Earth's orbit around the sun.
The tilt in the axis of the Earth is called its obliquity by scientists.

Explore examples of how simple geometry can be used to determine distances and sizes of otherwise inaccessible objects

...

Explain the contribution of ancient civilizations on modern astronomy

Ancient astronomers were able to differentiate between stars and planets, as stars remain relatively fixed over the centuries while planets will move an appreciable amount during a comparatively short time.

Understand how the observed motion of the planets led to the heliocentric view of our solar system

...

State Kepler's Laws of planetary motion

Kepler's three laws of planetary motion can be stated as follows: (1) All planets move about the Sun in elliptical orbits, having the Sun as one of the foci. (2) A radius vector joining any planet to the Sun sweeps out equal areas in equal lengths of time

Explain Newton's laws of motion and his Law of Universal Gravitation

v

Outline basic properties of wave motion

These also carry energy, but do not involve the mass movement of air from one place to another. A simple type of wave is illustrated below. ... Amplitude: the height of the wave, measured in meters. Wavelength: the distance between adjacent crests, measur

Describe how electromagnetic radiation transfers energy through space

Infrared radiation is a type of electromagnetic radiation. It involves waves, rather than particles. Unlike conduction and convection, radiation can even work through the vacuum of space. This is why we can still feel the heat of the Sun even though it tr

Know the major forms of energy represented in the electromagnetic spectrum

microwaves, infrared light, ultraviolet light, X-rays and gamma-rays.

Describe the basic properties of "blackbody radiation

As the temperature of the blackbody increases, the peak wavelength decreases (Wien's Law). The intensity (or flux) at all wavelengths increases as the temperature of the blackbody increases. The total energy being radiated (the area under the curve) incre

Explain how we can tell the temperature of objects by observing their radiation

you see where its peak is on the blackbody curve

Understand the doppler effect in terms of the relative motion of a luminous body and or the motion of the observer

The Doppler effect is a shift in the frequency or wavelength of radiation emitted from an object as it moves with respect to an observer