Open Cluster

Caldwell 16

Caldwell 16, a moderately bright and visually appealing open star cluster with a compact angular diameter, is situated in the constellation Lacerta in the northern hemisphere.

NGC 7243, or Caldwell 16, is a visually stunning open star cluster nestled in the Lacerta constellation. Notable for its arrangement of relatively young, hot, and luminous stars, the cluster exhibits a captivating celestial choreography. With a distinct blue hue characteristic of youthful stars, NGC 7243 offers a striking contrast against the cosmic backdrop. Estimated to be around 20 million years old, this cluster serves as both a picturesque astronomical sight and a valuable window into the early stages of stellar evolution.

Location of Caldwell 16

Caldwell 16 is situated in the constellation Lacerta (The Lizard) in the northern hemisphere of the sky. Lacerta is a relatively small and inconspicuous constellation nestled between the more prominent constellations of Cygnus, Pegasus, and Andromeda. This region of the sky provides a serene yet intriguing backdrop for observing this open star cluster.

Unique facts

  • Caldwell 16 stands out for its remarkable age diversity among its members. The open star cluster hosts stars of different ages, suggesting that star formation in NGC 7243 did not occur simultaneously but over an extended period.
  • Some stars within NGC 7243 are recognized as variable stars, indicating periodic fluctuations in their brightness. Studying such stars in open clusters provides valuable insights into the physical properties and evolutionary stages of stars.

Brightness and size

NGC 7243 exhibits a moderate brightness, with an apparent magnitude typically ranging around 6 or 7, making it visible to the naked eye under dark sky conditions and easily observable with binoculars or small telescopes. In terms of size, this open star cluster has a relatively compact angular diameter, measuring a few arcminutes across when observed from Earth. The apparent size of NGC 7243 in the night sky is influenced by its distance, contributing to its visual appeal as a suitable and rewarding target for amateur astronomers.