This is a pretty nice open cluster, according to Wikipedia, it was
probably discovered by Giovanni Batista Hodierna sometime before 1654.
Our boy Messier included it in his catalogue in 1764.
It contains some 19 white dwarfs, some 17 are DA or DAZ spectral type
(shouldn't keep you up at night). It is approx 1,500 light-years from
earth and spans some 35' making its radius of about 7
light-years. According to astronomers, age wise this open cluster
is approx 200-250 million years old.