Q 01/05

How many constellations does the International Astronomical Union officially recognise?

A) 88

B) 66

C) 72

D) 80

Answer · why

A) 88

By 1930 the whole sky had been carved into 88 tidy regions so that every star belongs to exactly one of them.

Q 02/05

Which constellation is the largest of all, sprawling across roughly 1,303 square degrees of sky?

A) Ursa Major

B) Centaurus

C) Cetus

D) Hydra

Answer · why

D) Hydra

The water snake is more than 100 degrees long but has only one reasonably bright star, Alphard, whose name means 'the solitary one'.

Q 03/05

Which constellation is the smallest by area, yet one of the southern sky's most recognisable?

A) Sagitta

B) Equuleus

C) Crux

D) Circinus

Answer · why

C) Crux

The Southern Cross covers just 68 square degrees, and the ancient Greeks knew its stars only as part of a neighbouring constellation before precession...

Q 04/05

How many constellations did Ptolemy list in the Almagest in the 2nd century AD?

A) 52

B) 60

C) 72

D) 48

Answer · why

D) 48

All but one of the figures survive today; the exception, a giant ship, was carved up in the 18th century.

Q 05/05

Which ancient constellation, the ship of the Argonauts, was broken up into Carina, Puppis and Vela?

A) Cetus

B) Eridanus

C) Argo Navis

D) Piscis Austrinus

Answer · why

C) Argo Navis

It is the only one of Ptolemy's 48 constellations no longer recognised as a single figure, and its brightest star Canopus now belongs to Carina, the k...