The Trapezium is the most famous multiple star system in the entire night sky. Located at the very heart of M42, the Orion Nebula, it is one of the youngest star clusters known.
The four brightest stars in the Trapezium (A, B, C and D) are easily visible in a four inch telescope with decent optical quality under good seeing conditions. They range in brightness from magnitude 5 to magnitude 8. They can be seen with the unaided eye as the middle star in the sword of Orion.
The image above shows the four brightest stars of the Trapezium very close together at the center of the photo. This image was taken with a 5 inch telescope in visible light. The Trapezium lies at the front surface of a massive, dusty molecular cloud that is teeming with newborn stars