Stars

How do we describe a star?

• A star is a massive ball of plasma that emit light in all direction

• Stars are massive ball of fire

• Stars are celestial bodies made up of oxygen

• Stars have pointy edges similar to Christmas star.

What are the characteristics used to describe a star?

• Brightness

• Shape

• Color and Surface temperature

• Size

What do we mean by a star’s luminosity?

• It pertains to brightest star

• True brightness or the absolute brightness of a star

• Brightness from a distant

• Brightness based on location of the obsever

How does luminosity affect the brightness of a star?

• It makes Blue stars appear dimmer

• It makes all stars to have equal brightness

• The higher the luminosity of the star, the brighter.

• It makes Red stars hotter

What do we mean by star's apparent magnitude.

• Apparent brightness is the perceived brightness of a star as observed from the Earth.

• It is the Brightness only from the surface

• It pertains to the location of the star

• Apparent magnitude show the stars true brightness

How does apparent magnitude affect the brightness of a star?

• It shows the average brightness of a star

• More distant means dimmer.

• Much closer means brighter

• Apparent magnitude show the stars true brightness

Can you name the closest star on Earth? What is its color?

• The Sun and it is a yellow star

• Proxima Centauri and it is a red star

• It is the Rigel which is a blue star

• Its the Polaris of the North

What color of a star is the hottest? Give example

• Blue/Alnilam

• Red/Betelguese

• Yellow/Sun

• White/White dwarf

What color of a star is the coldest? Give example

• Blue/Alnilam

• Red/Betelguese

• Blue/Rigel

• White/White dwarf

How does color and surface temperature are related to a star’s brightness?

• Stars that have blue color are hotter, thus, they are brighter

• The color depends on the surface temperature

• The color and surface temperature are not related to each other

• Stars that have red color are colder, thus, they are dimmer