Trapezium Cluster

The trapeze (also θ1 Orionis ) is an optical multiple star in the Orion Nebula. It consists of four stars, all of which are each physical multiple stars. In fact, the keystone is the brightest component of a very densely packed open cluster ( Orion Trapezium pile ) with a diameter of about 1.5 light years at the center of the Orion Nebula.

Astronomical significance

The Trapezium stars have formed directly from the material of the Orion Nebula about 300,000 years ago, and encourage him today by ionization glow. They drive the gas and dust cloud apart by their stellar wind and give rise to a spheroidal cavity whose interior is illuminated by the ionizing radiation and so the forms from Earth clearly visible part of the Orion Nebula. The stars in the trapezium have masses between 15 and 40 solar masses. The Trapeziumhaufen is a younger subgroup of the larger Orion Nebula - cluster, which consists of about 2000 stars spread over only about 20 light years.

Discovery history

In 1610, the French astronomer Nicolas Claude Fabri de Peiresc turned his telescope was the first in this region. He is now regarded as the discoverer of the trapezoid. Some years later, in 1617, Galileo Galilei observed this region. His observations he wrote extensively down in his notebook. From the trapeze he saw the three lighter components A, C and D. He noted that the components A and D are about equally bright and the component C have the same distance. Furthermore, the components A and D are so close to C that they touch this practical. This Theta Orionis 1 was the first star, which was resolved with a telescope into several components. In 1656 the Dutch astronomer Christiaan Huygens observed the Orion Nebula. Because of his drawing was Christiaan Huygens until the 19th century as the discoverer of the Orion Nebula and the trapezoid. However, he saw - as Galileo Galilei before - of the actual trapeze stars at first only three. Abbe Jean Picard in 1673 discovered a fourth star on the inside. Christiaan Huygens also observed this star in 1684 and later called this group of four " Trapezium ".