Spectral Classes Quiz

What are the spectral classes in order?

• OABMFGK

• ABFGKMO

• OBAFGKM

• MAFOBKG

Who proposed the Harvard System of stellar classification?

• Williamina Fleming

• Annie Jump Cannon

• Edward Pickering

• Thomas Harvard

Which of these could be the temperature of an F class star?

• 3000 K

• 7000 K

• 17 000 K

• 30 000 K

Which of these could be the temperature of an M class star?

• 3000 K

• 7000 K

• 17 000 K

• 30 000 K

What class is the Sun?

• F

• G

• K

• M

What class is an orange star?

• A

• F

• G

• K

What are the prominent absorption lines in an A class star?

• H (strongest)

  ionised metals

• He+, He, H

• ionised and neutral metals

• neutral metals, TiO

What is the extra class, P, used for?

• Planets

• Black Holes

• Supernovae

• Planetary Nebulae

What is the temperature of a white star?

• 6500 K

• 8500 K

• 12 500 K

• 35 000 K

What are Balmer Lines?

• Hydrogen lines from/to the n=1 energy level

• Hydrogen lines from/to the n=2 energy level

• Helium lines from/to the n=1 energy level

• Helium lines from/to the n=2 energy level