M42 The Orion Nebula

The Orion Nebula is a large and very bright nebula. Itīs 1500 l.y. away in the constellation Orion. The Orion Nebula is alsio known as M42 or NGC 1976. The nebula covers more then 1°x1° of the sky and can easilly be seen with the naked eye. It looks like a fuzzy patch around the quadruple stars, Theta Orionis which is also known as the Trapezium. From the Trapezium wafts ultraviolet light that ionizes the nebula. The nebula is over 20 l.y. in diameter, thirty l.y years across and like I said previously, 1500 l.y. away. If somenone could take 2.5-centimeter (1-inch) diameter core sample right through it, the total weight of material collected would just about counter-balance a small coin, which is about 3.5 grammes. The Orion Nebula is yet a stellar birthplace, where fresh stars are being formed. It contains very young stars of T-Tauri-type. They havenīt reached the Main Seaquens that means they are varying irregularly; there are also immensly powerful stars which we can detect because their infra-red radiation is not blocked by dust. The Nebula is very big, in fact M42 is just a small portion of huge molecular cloud which covers almost the whole Orion. Many of the stars in Orion are hot and young, evolving rapidly and ending their lives in colossal explosions called supernovae. They are born and die in periods of tens of millions of years. The first person to resolve individual stars (the Trapezium) in the inner region of M42 was Christian Huygens in 1656. The stars are perhaps only 25.000 years ago. They are very blue colored or perhaps white. From them proceeds very strong stellarwind. Now have mensuartions by the Hubble Space Telescope shows that the stellarwind is so remarkably strong that the Trapezium stars blows away all the material needed to form planets. The material ablates and drifts away into space. For example the ablate is so fast that it corresponds about three moons, like ours, would be blown away.

         M Number  NGC   Const   Mag     RA       dec       Type
     -----------------------------------------------------------------
           M42    1976   Orion    5   05h 35.4m  -05° 27ī   Great
                                                            Nebula