year ten earth & space science

Three features of a planet

Is in orbit around the sun, is spherical in shape, has cleared neighbourhood around orbit

What is a solar system

A sun and all of the celestial bodies bound by its gravitational field

What is a galaxy

A huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity

Our solar system is part of a spiral - shaped galaxy called…

The Milky Way

What is a star

A giant ball of hot, glowing gases

What are most stars made almost entirely of

Hydrogen and helium

What can stars vary in (five things)

Size, mass, temperature, age, luminosity (brightness)

What is a moon

A celestial body that makes an orbit around a planet

What is a nebula

A big cloud of dust and gas

What are the first three forms of stars

Nebula, protostar, main sequence star

What determines whether a star becomes a red giant or a red super giant

If it was originally massive it will become a red super giant

Describe supernova

Up to forming iron, implodes, metals ejected across universe

What evolution of red super giant is extremely dense

Neutron star

Describe the big bang theory

All matter created at a single point in time at the beginning of the universe

Describe the steady state theory

Matter was continuously created over time

Difference between big bang theory and steady state theory

Big bang theory says universe expands and density thins. Steady state theory says universe expands and density remains constant