AST 111 - Astronomy Quiz 1 Review

Vocabulary flashcards generated from AST 111 Quiz 1 study material covering basic astronomy scales, atomic structure, scientific notation, and scientific methods.

The Sun

The star at the center of the Solar System, orbited by Earth and the other planets.

Milky Way Galaxy

The galaxy in which we live, containing our Solar System as one of many star systems.

Number of Stars in the Milky Way

Roughly $100-400\text{ billion}$ stars.

Scale of Earth (Grapefruit Sun Model)

About the size of a small seed or pinhead, roughly $1-1.5\,mm$ across, when the Sun is the size of a grapefruit.

Distance to Next-Nearest Star (Grapefruit Sun Model)

On the order of a few thousand miles away if the Sun were the size of a grapefruit in Washington, DC.

Atom

The basic unit of ordinary matter that retains the properties of an element, consisting of a nucleus surrounded by electrons.

Protons, Neutrons, and Electrons

Subatomic particles that make up atoms. Protons and neutrons are located inside the nucleus, while electrons reside outside the nucleus.

Subatomic Particle Charges

The electric charges of subatomic particles: electron = negative ($-1$); proton = positive ($+1$); neutron = neutral ($0$).

Nucleus (Atomic)

The central part of an atom containing protons and neutrons.

Electrons (Atomic Location)

Subatomic particles positioned outside the atom's nucleus in regions called orbitals or the electron cloud.

Scientific Notation for Large Numbers

A process where the decimal is moved LEFT until one nonzero digit remains before it, resulting in a POSITIVE exponent (e.g., $45,000,000 = 4.5 \times 10^7$).

Scientific Notation for Small Numbers

A process where the decimal is moved RIGHT until one nonzero digit remains before it, resulting in a NEGATIVE exponent (e.g., $0.0000062 = 6.2 \times 10^{-6}$).

Converting Scientific Notation to Regular Numbers

Moving the decimal to the RIGHT for a positive exponent and to the LEFT for a negative exponent (e.g., $3.2 \times 10^5 = 320,000$; $4.7 \times 10^{-4} = 0.00047$).

Scientific Hypothesis

A testable and falsifiable proposed explanation for an observation or phenomenon.

Scientific Model

A simplified representation of a real object, system, or process used to explain observations and make predictions.

Scientific Theory

A broad explanation of natural phenomena supported by extensive evidence that has survived repeated testing, makes testable predictions, and remains consistent with observations.

Scientific Law

A description of a consistent pattern or relationship in nature. It differs from a theory because a theory explains why or how phenomena occur, and a theory does NOT become a law.