We all know that most of the constellations have a major or bright star. However, there is a constellation in the night sky that is faint and none of its stars are brighter than the fourth magnitude. Caelum is one such constellation. It represents a sculptor’s Chisel and is found in the southern hemisphere between the older constellations of Columba the Dove and Eridanus the River. It belongs to the Lacaille family of constellations and was charted by Nicholas Louis de Lacaille, a French astronomer in the 18th century. It can be best visible during the month of January at 9 pm. Caelum occupies a relatively small and barren area of sky which is set apart from the Milky Way and hence, has been described as more of a blank space than a constellation.
Caelum does not have many bright stars but of the numerous stars, a few notable stars include:
- Alpha Caeli: It is the brightest star in the constellation although its apparent magnitude is just 4.44. It is one of the old constellations, about 900 million years old and is approximately 65.7 light years distant from the earth. Its primary component is an F–type main sequence star which is Alpha Caeli A.
- Gamma Caeli: It is shared by two star systems namely gamma–1 Caeli and gamma–2 Caeli. They are separated by 0.22° in the sky. The system in a small telescope resolves into a red giant and a white giant with magnitudes 4.5 and 6.34 respectively.
- Beta Caeli: It is a yellow–white F–type main sequence dwarf and is the third brightest star in Caelum. With luminosity more than six times than that of the sun, its magnitude is about 5.04 and is approximately 90.2 light years distant from the earth.
- Delta Caeli: It is a blue–white B–type subgiant. With an apparent magnitude of about 5.07, it is approximately 711 light years distant.
- Nu Caeli: It is a yellow–white F–type dwarf with a magnitude of 6.06 and is approximately 171 light years away from the earth.
- Lambda Caeli: It is an orange giant.
Based on the imaginative figure around the stars of this constellation, it was named as ‘les Burins’ meaning ‘sharp engraving tools’. However, later it was translated into Latin and was called Caela Sculptoris, meaning ‘the sculptor chisel’ and much later was shortened to Caelum. The word Caelum means ‘chisel’.
Caelum does not have any deep sky objects but a few faint galaxies. Some of them include NGC 1679, which is a spiral galaxy located about two degrees to the south of Zeta Caeli; NGC 1571; and IC 2106.
Caelum is located in the first quadrant of the southern hemisphere between latitudes +40° and -90°.
Caelum constellation occupies 125 square degrees of space, making it the eighth smallest constellation in the sky. Most of the times, the distance of a constellation is difficult to mention due to the different locations of its major stars. One of its stars is about 800 square degrees light years away from the earth. Hence, it can be said that its distance from the earth is 800 light years.
There are no myths or stories associated with this constellation. Lacaille named it after various instruments and tools instead of stories and narrations.
Caelum neighbours constellations such as Columba, Dorado, Eridanus, Horologium, Lepus and Pictor.
