ζ Hydrae and The Hydra's Head

Zeta Hydrae is an orange giant (seven to ten times the size of the Sun) which forms the top of the neck of the Hydra, and is the brightest star in the asterism known as The Hydra's Head, which barely fits into a 5 binocular field of view.

From amongst this group of stars epsilon Hydrae is the most remarkable, as it is a splendid multiple binary of close components:
      AB: 3.5, 5.0; 176, 0.3" (orbit of 15.06 years.)
      AC (yellow and blue): 3.5, 6.7; 304, 2.7" (orbit of 990 years.)

Two more binaries are in this small group: Struve 1255 and Struve 1290:
      Struve 1255 (white/pale orange-reddish): 7.3, 8.6; 33, 26.2".
      Struve 1290: 7.4, 9.2; 325, 2.8".

Southeast one binocular field brings you to theta Hya: binoculars.

But before we proceed down the Hydra's neck we'll visit an isolated and 'missing' Messier object, M48.

From the Hydra's Head move about two and a half binocular fields southwest: M48 is the rogue cluster that isn't where Messier said it was. It has since been decided that Messier intended NGC 2548 to be his M48, which is 4 off his published location.

M48 is easily found in binoculars as a tight group of about fifty bright stars with an apparent magnitude of 5.5.

On now to theta Hydrae and beyond. Click on this star on the map to continue.

All files associated with The Constellations Web Page are
1999-2014 by Richard Dibon-Smith.