The cluster of stars known as the Pleiades or Seven Sisters have moved on compared to the Orion Nebula, and have blown away most of the surrounding cloud of gas and dust to be revealed as blue-white young stars.
Young stars are much brighter in X-rays than middle-aged stars such as the sun. Stars do not form in isolation, but in clusters which can have thousands of members, so most young stars are found in clusters.
Orion Nebula in Oxygen, Hydrogen, and Sulfur Image Credit Copyright: César Blanco González The Orion Nebula spans about 40 light years is about 1500 light years away in the same spiral arm of our Galaxy as the Sun. The Great Nebula in Orion can be found with the unaided eye just below and to the left of the easily identifiable belt of three stars in the popular constellation Orion.The whole Orion Nebula cloud complex, will slowly disperse over the next 100,000 years.
The Dandelion Cluster is a group of stars located 5000 ly away, backdropped by the center of the galaxy. This cluster collapsed from a large gas cloud about 200 Ma and weighs about 300 solar masses. Remnants of the cloud are visible, blocking light from the stars behind them