Orion’s Shield

To complement its more famous Belt and Sword, the constellation of Orion is also equipped with a Shield, represented by a shallow arc of stars running north to south along the western borders of the constellation, separating it from neighbouring Taurus.

Though now generally known as Orion's Shield, this part of the constellation was described by ancient writers as a lionskin, and indeed older illustrations of Orion often show him holding up a skin or a shield emblazoned with the emblem of lion. This association hints at an ancient connection of Orion with the legends of Hercules (who was sometimes depicted holding the skin of the slain Nemean Lion in a similar posture) though whether such a mythological connection actually existed remains unclear.

The six main stars that make up the Shield's bowed shape are all designated Pi on the Bayer system, running from Pi¹ Orionis at the northern end to Pi⁶ Orionis at its southern tip. Some sources also extend the Shield northward to encompass Omicron² or Omicron¹ Orionis (as a traditional asterism rather than a formal constellation, there is no official definition of the Shield's stars).

Most of the stars that make up the Shield are extremely distant from the Solar System, especially those in the southern part of the structure (which are generally a thousand light years distant or more). A significant exception is Tabit or Pi³ Orionis, a bright yellow dwarf star that shines as the brightest of the Shield's stars in the sky because it lies just 26 light years from the Sun.