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The famous trapezium lies buried deep within the Orion Nebula. It is primarily made up of four bright stars, but is also generally considered to include several fainter stars in the vicinity. This object would be striking anywhere in the sky, but is particularly appealing (not to mention easy to find) within the famous M42 nebulosity.

The stars of the Trapezium make up the Theta¹ Ori system, with Theta¹ Ori as the primary. The four brightest components (A, B, C, and D) are traditionally lettered in RA order instead of the magnitude order used for other multiple stars.  These four brightest members are visible in even the smallest telescope using high magnification.

The primary star, 6.7-magnitude Theta¹ Ori, is also the variable star V1016 Ori, an Algol-type eclipsing binary system that becomes fainter by about a magnitude when the smaller, brighter star passes in front of the larger, cooler one. These stars are so close together that no telescope can split them apart. Eclipses occur every 65 days.

Star B is also an eclipsing binary, known as BM Ori. It undergoes a primary eclipse every 6.5 days, dimming by 0.76 magnitudes.

Star C is HD 37022, a 5.1 magnitude star suspected of small variability.

Star D is HD 37023, a 6.7 magnitude star also suspected of small variability.

Stars E and F should be visible in a 6-inch scope under good conditions. Stars G and H are quite difficult, typically requiring large aperture and good seeing.

Diagram of the system, north is down and east is to the right.

The view in six inch at 50x. North is down and east is to the right.