Download Astronomers classify stars according to their physical characteristics

Astronomers classify stars according to their physical characteristics.
These include the following properties: .
Chemical Composition
•Scientists study the star’s _______ _______ __________ to
determine what it is made of. Stars vary in their composition, but most
are made of _____________, _____________, and a small amount of
_____________ ______________.
KEY:
Chemical Composition
•Scientists study the star’s _black_ _line _ _spectrum__ to
determine what it is made of. Stars vary in their composition, but most
are made of _hydrogen___, _helium___, and a small amount of
_other_ _elements__.
Brightness
•How bright a star _______ ____ ______ _______ here on Earth is
called its _______________ ______________ or brightness.
•A star’s _______________ brightness depends upon how
bright it _____________ ______ and its ___________ from Earth.
•A star’s actual brightness (or ______________ ________________)
usually depends on the star’s _______ and ___________________.
•Because stars with _________ __________ have more ______________________, they tend to have ______________ temperatures
and burn _______________.
Size
•Very large stars are called _________ or ________________ stars.
•Our sun is a ______________-sized star.
•Most stars are __________________ than the sun.
•White dwarfs are about the size of ________________.
•______________ stars are about 20 km in diameter.
Color and Temperature
•A star’s __________, color, and temperature are all closely related.
•___________ and _____________ stars have the ______ ________
and burn at the _______________temperatures.
•Yellow, Orange, and Red stars have ______ _______ and burn at
_____ temperatures.
•Our sun is a ____ _______ star and is a ______________ color.
•Scientists study the star’s _______________ to find its temperature.
•Our sun has a surface temperature of about _____________.
Brightness
•How bright a star looks to our eyes here on Earth is
called its _apparent magnitude__ or brightness.
•A star’s _apparent_ brightness depends upon how
bright it _actually is and its _distance_ from Earth.
•A star’s actual brightness (or _absolute magnitude)
usually depends on the star’s _size_ and temperature__.
•Because stars with _more mass ___ have more __self
_gravity, they tend to have _higher__ temperatures
and burn _brighter__.
Size
•Very large stars are called _giant_ or _supergiant___ stars.
•Our sun is a _medium_-sized star.
•Most stars are _smaller__ than the sun.
•White dwarfs are about the size of __Earth_.
•__Neutron_ stars are about 20 km in diameter.
Color and Temperature
•A star’s _mass_, color, and temperature are all closely related.
•_Blue_ and _white stars have the _most mass__
and burn at the highest_temperatures.
•Yellow, Orange, and Red stars have _low mass_ and burn at
_low_ temperatures.
•Our sun is a _low mass_ star and is a __yellow_ color.
•Scientists study the star’s _spectrum_ to find its temperature.
•Our sun has a surface temperature of about _5500°C_.