  We present bispectrum speckle interferometry observations with the SAO 6 m
telescope of the four brightest stars in the Orion Trapezium.
Diffraction-limited images with an unprecedented resolution lambda/D of 57 mas
and 76 mas were obtained in the H- and K-band, respectively. The The H and K
images of Theta1 Ori C (the star responsible for the proplyds) show for the
first time that Theta1 Ori C is a close binary with a separation of only 33 mas
(H-band observation). The sub-arcsecond companions of Theta1 Ori A and Theta1
Ori B reported by Petr et al. (1998) are confirmed. We use the magnitudes and
colors of the companions to derive information about their stellar properties
from the HR-diagram. In addition we briefly discuss the multiplicity of the
Trapezium stars. Considering both, the visual and the spectroscopic companions
of the 4 Trapezium stars, there are at least 7 companions, i.e. at least 1.75
companions per primary on average. This number is clearly higher than that
found for the low-mass stars in the Orion Nebula cluster as well as in the
field population. This suggests that a different mechanism is at work in the
formation of high-mass multiple systems in the dense Trapezium cluster than for
low-mass stars.
