Delphinus, the Dolphin, is a small, neat constellation of the northern summer sky, a diamond of stars with a short tail leaping just east of Altair.
At a glance
| stars in the figure | 5 |
|---|---|
| nearest star of the figure | Rotanev, 101 light-years (30.9 pc) |
| farthest star of the figure | Aldulfin, 330 light-years (101 pc) |
| depth | the farthest is 3.3 × farther than the nearest |
Read off the piece’s own catalogue, the same values it draws with.
About Delphinus
Delphinus is an ancient Greek constellation, a dolphin in the service of Poseidon. Its four brightest stars form a small diamond known as Job’s Coffin, with Aldulfin marking the tail. Two of its stars, Sualocin and Rotanev, carry a hidden joke: read backwards they spell Nicolaus Venator, the Latin name of the assistant astronomer at Palermo whose catalogue gave them their names.
Though faint, the dolphin is easy to pick out because its stars are close together and the patch of sky around it is fairly empty. Gamma Delphini, at the nose, is a pretty double in a small telescope. Delphinus lies near the Summer Triangle and is best seen on northern summer and autumn evenings.
What you see in the piece
Flown out to, even this tight little diamond loosens: Rotanev is the nearest star of the figure and Aldulfin lies a few times deeper, so the dolphin stretches out along the line of sight.
Questions
Why are Sualocin and Rotanev called that?
Spelled backwards they read Nicolaus Venator, the Latinised name of Niccolò Cacciatore, who worked at the Palermo observatory where the names were first recorded.
How far away are the stars of Delphinus?
They range from Rotanev, 101 light-years (30.9 pc), to Aldulfin, 330 light-years (101 pc): the farthest is 3.3 × farther than the nearest.