About this episode
This episode explores the constellation Serpens, detailing its two parts and notable stars.
The sky is divided into 88 official constellations. In fact, though, it’s more like 88 and a half. That’s because the constellation Serpens consists of two disconnected parts – a head and a tail. They wrap “behind” the body of Ophiuchus the serpent bearer. Serpens is in full view in the east and southeast by a couple of hours after sunset. The half that represents the head is highest, above Ophiuchus, with the tail below the serpent bearer. The front of the snake, Serpens Caput, is the more prominent half. It has several stars that are fairly easy to see. The brightest is Alpha Serpentis, also known as Unukalhai – “the serpent’s neck.” It’s a red giant – an old, bloated star that’s much bigger and brighter than the Sun. Its surface is much cooler than the Sun’s, so the star looks yellow-orange. The back half of the snake, Serpens Cauda, is tougher to spot. Its brightest star, Eta Serpentis, is the second-brightest star in the whole constellation. It’s about half as bright as Alpha. But the two stars are quite similar. Eta is also a giant – a puffed-up star that’s nearing the end of its…
People in this episode
Host: Billy Henry
Topics covered
- constellations
- astronomy
- stars
- Serpens
- Ophiuchus
- night sky
Keywords
- Serpens
- Ophiuchus
- Alpha Serpentis
- Eta Serpentis
- constellations
- astronomy
- night sky
Mentioned in this episode
Books & works: Serpens, Ophiuchus, Alpha Serpentis, Unukalhai, Eta Serpentis
More episodes of StarDate
- ‘Shifting’ Stars · June 12, 2026 · 2 min
- Evening Array · June 11, 2026 · 2 min
- Tight Family · June 10, 2026 · 2 min
- Moon and Saturn · June 9, 2026 · 2 min
- More Venus and Jupiter · June 8, 2026 · 2 min
- Death-Ray Galaxy · June 7, 2026 · 2 min
Explore listener stats, chart rankings, contacts and more on the StarDate podcast page.