Finding it in the sky
When to look
Summer and fall nights, from June to November, almost overhead in the middle hours of the night. On summer evenings it is the figure that rules the upper part of the sky.
How to recognize it
Look for the brightest star almost straight overhead and from there follow a big cross: a long arm running downward and a shorter one across it, like open wings.
The main stars
- DenebAlfa Cygni
- AlbireoBeta Cygni
- SadrGamma Cygni
- FawarisDelta Cygni
- AljanahEpsilon Cygni
To get an idea
If Deneb were as close as the other bright stars, on its own it would light up the night almost like the Moon.
The Northern Cross is wider and more open than the Southern Cross, which can never be seen from the northern half of the world.
Fun facts
These are not in the book: there was no room on paper.
The name Albireo means nothing: it was born from a chain of mistaken translations lasting centuries.
A series of dark clouds splits the Milky Way in two right here, and it is called the Cygnus Rift.
Hidden in this constellation is Cygnus X-1, one of the first black holes ever suspected.
Just east of Deneb there is a cloud of gas that in photographs looks like North America.
In the myth the bird is Zeus in disguise, flying down to the Earth to visit Leda.
Deneb is the farthest of all the brightest stars in the sky.
Test yourself
The first question is the one printed under the QR code, with the answer the book did not give. The other four only exist here.
Question 1 of 5★ is the one from your book
What is the asterism of Cygnus called?
Question 2 of 5
Why is Deneb surprising?
Question 3 of 5
What do binoculars show when pointed at Albireo?
Question 4 of 5
When is Cygnus easy to see?
Question 5 of 5
Where does the Swan fly?
Riddles
I fly with open wings inside a river of stars, and whoever does not see me as an animal sees me as a big cross. On warm nights I am almost straight over your head. What am I?
My tail is called tail in Arabic too, and it is a star that looks like the others but is the farthest of all the brightest ones. What am I?
On my beak there is a single dot, which splits in binoculars: a drop of gold and a drop of blue, very close together. What am I?
Try it yourself
From a dark place, far from lights, see whether the cross sits inside a pale band. It is the Milky Way, and the Swan flies right through it.
Point binoculars at the bottom tip of the cross, where the beak is. The dot turns into two stars close together, one golden and one blue.
The words
- double star
- Two stars that look very close together when seen through an instrument.
- supergiant
- An enormous star, much bigger and brighter than the Sun.
Sources: Wikidata (Q10406), Wikipedia (Cigno (costellazione)).