Stars and the Universe

Which definition is this? A group of many billions stars to which sun belongs.

• Milky way

• Nebula

• Black hole

What is the length of a lightyear in metre?

• 9.5x10^15 m

• 8x10^15 m

• 5x10^15 m

What is redshifts?

• Redshift is the phenomenon where light is absorbed by an object moving away from the observer.
• Redshift refers to the brightness of light emitted by an object moving away from the observer.
• Redshift is the decrease in wavelength of light from an object moving towards the observer.
• Redshift is the increase in wavelength (or decrease in frequency) of light from an object moving away from the observer.

Big bang theory is.......

• A theory about the formation of black holes.
• An explanation of how stars are formed.
• The Big Bang Theory describes the origin and expansion of the universe.

What two pieces of evidence support Big Bang theory?

• 1. Redshift of distant galaxies 2. Cosmic microwave background radiation
• 1.Presence of dark matter

  2. 2. Redshifts of star

• 1.Formation of black holes

  2. 2. Formation of supernova