With the aid of new data from the ESA Gaia satellite, astronomers updated the study of IC 4996 and its surroundings. IC 4996 is a young open cluster living in the constellation Cygnus. Acts as a member of the association Swan OB1.
Despite numerous reviews, age and distance remained uncertain. Some believe that they are at a distance of 5400 light years, while others point to 2400 light years. The age varies between 6-9 million years.
Open Cluster IC 4996
To eliminate inaccuracies and penetrate deeper into the nature of IC 4996, scientists conducted a new study. For this purpose, the 1.8-meter telescope VATT (Arizona) and information from the second edition of Gaia (DR2), published in April 2018, were used. In DR2, there are highly accurate measurements, including positions in the sky, parallaxes and correct movements for more than 1 billion sources of the Milky Way. Gaia data analysis showed that the parallax for IC 4996 is 0.552, which corresponds to a distance of 6243 light years. And the age of clusters was estimated at 8-10 million years. The distance to the association Swan OB1 reaches 5483, which means IC 4996 can no longer be considered a member. However, researchers note that the cluster is most likely endowed with a common origin with the association.
Scientists note that they also managed to find 72 new possible members of the cluster from the DR2 data set.