Q 01/05

Polaris is the brightest star of which constellation?

A) Ursa Major

B) Draco

C) Ursa Minor

D) Cepheus

Answer · why

C) Ursa Minor

Its designation is Alpha Ursae Minoris; it marks the tip of the Little Dipper's handle.

Q 02/05

What kind of star is Polaris Aa, the main component of the system?

A) Red dwarf

B) White dwarf

C) Blue giant

D) Yellow supergiant

Answer · why

D) Yellow supergiant

It is spectral type F7Ib, with about five times the Sun's mass and a radius 46 times larger.

Q 03/05

Polaris looks like one star but is actually how many?

A) One

B) Two

C) Five

D) Three

Answer · why

D) Three

Polaris Aa and its close companion Ab are orbited at a distance by Polaris B; two further 'companions' turned out to be unrelated.

Q 04/05

Who discovered Polaris B, the outer companion, in August 1779?

A) Edmond Halley

B) Charles Messier

C) Caroline Herschel

D) William Herschel

Answer · why

D) William Herschel

He used a reflecting telescope of his own making; the inner pair was only confirmed in the early 20th century.

Q 05/05

Which space telescope first resolved all three members of the Polaris system in January 2006?

A) Spitzer

B) Chandra

C) Hubble

D) Kepler

Answer · why

C) Hubble

The CHARA Array later refined the inner orbit and put the supergiant's mass at about 5.1 solar masses.