#caldwell 91

[quiltofstars]

The Wishing Well Cluster, C91 // Alexandre Fagundes

Seen here against a backdrop of nearby nebulosity, the Wishing Well Cluster (NGC 3532) is an open cluster of stars located about 1,320 light years away in the constellation of Carina, the Keel. Discovered by Nicolas-Louis de Lacaille (1713-1762) in 1752, it was also admired by John Herschel (1792-1871) who said about it, "It is the most brilliant object of the kind I have ever seen."

[zespaceblog]

NGC 3532 (Caldwell 91)

Open clusters are the remains of a once intense star birthing nebula that has over time slowly lost most of the beautiful colours and dust clouds, leaving behind a group of stars gravitationally bound to one another in a cluster, sharing similar trajectory and speed as they orbit the Milky Way. Our own Sun would have remained part of its birthing cluster for many millions of years after its birth, now slowly over time the group breaks up and follows its own path around the galaxy.

What makes this open cluster in the Southern sky and constellation of Carina, not too far from the Southern Cross, is the backdrop, both a small remnant of the hydrogen gas glowing while it's bombarded with ultra violet light, but also the much further backdrop of the Milky Way, making the darkness of the sky almost full of stars, some over 20-30,000 light years behind.

Finally, the age of the cluster , at about 300 million years old, many of the stars in the cluster are blue giants, and have quickly passed through their main sequence, and turned red giant, contrasting with the blue stars, making it like a jewel box of stars.

[quiltofstars]

The Wishing Well Cluster, C91 // Alex Nicholas

Zooming out, we see that the Wishing Well Cluster (NGC 3532) is a truly beautiful cluster of about 150 stars. There are several red giant stars in the cluster, giving observers beautiful contrasting colors. The bright yellow star seen to the top left of the cluster is the star x Carinae, but it lies between the Sun and NGC 3532 and is not a member.

The Wishing Well Cluster was also the first target ever observed by the Hubble Space Telescope on May 20, 1990.