Astronomy Concepts

What is the electromagnetic spectrum used for? (name 3 purposes)

Determine composition & age of stars

Measure speed of objects travelling towards or away from Earth

Measure distance between objects in space

Scientific notation is used to _____

condense very large or very small numbers into a more manageable size

Radiation is the emision of ____

energy

List the 4 types of radiation

Electromagnetic (Light)

Particle (Radioactivity)

Acoustic (Sound)

Gravitational

The sun, radioactive isotopes, and other celestial objects are examples of ___

natural electromagnetic radiation

The 3 characteristics of electromagnetic waves are:

Speed

Wave length

Frequency

The speed of EM radiation is always ___

the speed of light

The speed of light =

3.0 x 10^8 m/s

Wavelength and frequency are _____

inversely proportional

Inversely proportional means:

As one value gets larger, the other gets smaller

Fundamental particles make up ___

subatomic particles

___ makes up protons and neutrons

quarks

electrons are a type of ___

leptons

Fundamental particles have ___

no internal structure

Telescopes collect ____

electromagnetic radiation

Optical telescopes collects ____

visible light

Radio telescopes collects ___

radio waves

X ray telescopes collects ___

x-rays

Atmospheric Cherenkov telescopes collects ___

gamma rays

Galaxies are ____

gravitationally bound systems of stars, stellar remnants, interstellar gas, dust and dark matter

Number of observable galaxies in the universe is estimated to be around ___

2 trillion

Every star you see is ____

within the Milky way

The 3 types of galaxies are:

spiral

elliptical

irregular

All galaxies are ___

classified by shape and have a black hole at its center

2 unique characteristics of spiral galaxies

Flat discs with think centers

have spiral arms

2 unique characteristics of elliptical galaxies

Shaped nearly spherical to lense

No spiral arms

2 unique characteristics of irregular galaxies

Smaller and fainter

Stars spread unevenly

A galaxy cluster consists of anywhere from ___ to ___ of galaxies bound together

hundreds to thousands

Galaxy clusters are the _____

largest known gravitationally bound structures in the universe

The Milky Way is part of a cluster called:

The Local Group

An astronomical unit is ___

the distance between the Earth and the Sun

In kms, 1 AU =

150,000,000 kms

1 light year =

63, 241 AU

5 properties of stars are:

Brightness

Colour

Temperature

Mass

Composition

A star's properties helps understand its ___

life cycle

Brightness/luminosity measures the total amount of ___ the star gives off per ___

energy, second

The ___ of a star indicates its ____

colour, surface temperature

Lower temperature stars appear ___

red

Mid range temperature stars appear ___

yellow to white

Hot temperature stars appear ___

blue

Most stars are ___ (2 stars orbit one another)

binary

By knowing the size of orbit and time it takes 1 star to complete 1 orbit, the star's ___ can be calculated

mass

By measuring the ____, the ___ of stars can be determined

wavelengths, composition

A ____ gives pattern of spectral lines that is used to determine the specific elements within the star

spectroscope

The Hertzsprung-Russell Diagram is a way to view ___ between stars. It plots ___ against ___

trends, luminosity, temperature

Fusion is the nuclear reaction that produces ___ in the core of stars

energy

Multiple ____ fuse into a single heavier nucleus - releasing energy

light nuclei

Fusion can only happen under high ___ and ___

temperature, pressure

The common method of fusion among light-mass stars is:

hydrogen to helium fusion

The CNO cycle only occurs in ____

higher mass stars (1.3+ solar masses)

The CNo cycle is a type of ___

catalytic cycle

A ____ of forces forms a star

balance

Stars will eventually ___ of hydrogen to fuse

run out

Low to intermediate mass stars do not ___

have enough high temp & pressure to fuse past helium

A _____ forms when low to intermediate stars use up its helium

carbon-oxygen core

Massive stars can fuse up to ____

Iron

Near the end of a massive star's life, it will expand to become a ___

supergiant

Supergiants will explode in an event called a ___

supernova

The core of a supergiant is ____

made up of Iron

Black holes have ____

infinite density