which star color indicates an 8000k main sequence star? (1) blue (3) yellow (2) white (4) red

Which star color indicates an 8000K main sequence star?

(1) blue (3) yellow

(2) white (4) red

Orange stars with luminosity over 100,000 are classified how?

Light, stars, and the expanding universe…

Textbook Pages 612-616

Starlight travels in many colors.

Which type of electromagnetic energy has the longest

wavelength?

(1) infrared radiation

(2) radio wave radiation

(3) ultraviolet radiation

(4) x-ray radiation

Light Moves Fast!

300,000 Km/sec

(186,000 miles/sec)

Light takes .0000000002 seconds

Light takes about

1.5 seconds

Light takes

about 8.5

minutes

Light takes about 434 years to get here from POLARIS !

Are you seeing the way Polaris looks today?

Light can take billions of years to reach us!

Our telescopes really look into

the past.

Billions of years ago we see the energy

from the “Big Bang”.

There is also background radiation the big bang left behind!

Which evidence best supports the theory thatthe universe was created by an explosion called

the Big Bang?

(1) impact craters found on Earth

(2) cosmic background radiation

(3) the different compositions of terrestrial and Jovian planets

(4) the blue shift of light from distant galaxies