Unit E Science Exam Study

Geocentric Model

Earth at the center of the universe, supported by Aristotle.

Heliocentric Model

Sun at the center of the universe, proposed by Copernicus and supported by Galileo and Kepler.

Ellipse

Oval shape of planetary orbits.

Ecliptic

The Sun’s apparent path through the sky over the year.

Equinox

Equal day and night, occurs in spring and fall.

Solstice

Longest and shortest days of the year (summer = longest, winter = shortest).

Solar Winds

Stream of charged particles emitted from the Sun, protected by Earth's magnetic field.

Astronomical Unit (AU)

Distance from Earth to Sun, approximately 149,599,000 km.

Celestial Objects

Includes stars, constellations, galaxies (like the Milky Way), and solar systems.

Light-Year

Distance light travels in one year, equivalent to 9.5 trillion km.

Azimuth

Compass direction measured in degrees (N = 0°, E = 90°, S = 180°, W = 270°).

Altitude

Angle above the horizon; 0° is horizon level and 90° is directly overhead.

Asteroid

Rock in space, primarily found in the main belt between Mars and Jupiter.

Comet

Ice and dust object in space with a distinct tail, often referred to as a 'dirty snowball'.

Meteor

A meteoroid that burns up upon entering Earth's atmosphere.

Meteorite

A meteoroid that survives its passage through the atmosphere and lands on Earth.

Space Shuttle

A reusable spacecraft designed for human spaceflight.

Space Probe

An unmanned spacecraft that collects data from space environments.

International Space Station (ISS)

A human habitat for long-term missions in space.

Gravity

The force that pulls objects toward each other.

Microgravity

A condition of very weak gravity often experienced in orbit.

Remote Sensing

Observing Earth from a distance without direct contact.

Global Positioning System (GPS)

A technology that uses satellites to pinpoint locations on Earth.

Optical Telescope

A type of telescope that uses lenses or mirrors to gather and focus light.

Hubble Space Telescope

A telescope launched in 1990 that orbits Earth and takes high-quality images.

Spectroscope

An instrument that analyzes the light spectrum from stars to determine their elements.

Triangulation

A method of measuring distances by observing angles from two points.

Space Suit

Protective gear providing oxygen, temperature control, and pressure for astronauts.

Space Junk

Debris from satellites and rockets that poses risks to spacecraft.

Parallax

An apparent shift in position of an object when viewed from different locations.

Pros of Space Exploration

Advancements in technology, scientific knowledge, and global cooperation.

Cons of Space Exploration

High costs, creation of space junk, and risks posed to astronauts.