On the left is Mimosa the second brightest star in the constellation Crux, the southern cross at Magnitude 1.25 is the 19th brightest star in the sky.
Very close to Mimosa there’s a blood-red star, that’s DY Crucis a carbon star! Carbon stars are the reddest stars in the sky. Mimosa and DY Crucis are a beautiful blue-red pairing in the sky.
On the right side of the photo lies the beautiful star cluster known as the “Jewel Box” (NGC 4755). The cluster is centered around Kappa Crucis an orange star contrasting with the other members of the cluster.
There are no green stars in the sky but comets can look really green or cyan in color.
This is comet C/2012 F6 Lemmon in the middle of Crux, the Southern Cross.
Taken on January 20th it was bright at magnitude 6.
As a reference the reddish/orange star above the comet is Epsilon Crux a Mag 3.55 star.