3.1: Constellations Flashcards
What is a constellation
An area of sky containing the pattern of stars
What are asterisms
Smaller groups of stars that form familiar shapes
What are nebulae
Faint,fuzzy patches of light (Latin for cloud)
What is the brightest star in the sky
Sirius , magnitude -1.5
Where is the Orion Nebula located
Below the belt in the constellation of Orion
What stars does the asterism the winter triangle contain
Betelgeuse, Sirius and Procyon
Who created the scheme for labelling stars according to how bright they are
German lawyer and amateur astronomer Johann Bayer in the 17th century
When was the first list of constellations published
In 150 AD by Claudius Ptolemaeus
On a clear, moonless night, well away from light pollution how many stars is it possible to see
2,000
When did stars start being grouped in patterns called constellations
Since antiquity
Who was Nicolas Louis de Lacaille
A French astronomer who filled gaps in the southern sky, he sit up a small observatory under the Table Mountain at Cape Town, South Africa in 1750. From there he invented 14 new constellations an named them after important artistic and scientific instruments of the time
What did Lacaille divide
The large Greek constellation Argo Navis into 3 separate constellations: carina, puppis, and vela
When was the official list of constellations formally adopted and how many constellations were in the list
1822 by the International Astronomical Union. There were 88 constellation in the list
Why are stars above and below the ecliptic visible at all times of the year
Because the sun doesn’t obstruct their visibility
Why are some constellations visible all year long and some ‘seasonal’
The earth’s orbital motion around the sun and the fact that stars cannot be seen during the day
