Hydrocarbons in the Horsehead mane

[Orstio]

http://www.everything-science.com/index.php?option=com_content&task=view&id=114&Itemid=2

Observing the edge of the famous Horsehead Nebula with the IRAM interferometer located on the Plateau de Bures (France), a team of French and Spanish astronomers discovered a large quantity of small hydrocarbon molecules. This is a surprise because the intense UV radiation illuminating the Nebula should destroy the small hydrocarbons near the edge. The astronomers suggest that these molecules might result from the fragmentation of giant molecules, called - polycyclic aromatic hydrocarbons - (PAHs).

More than 120 molecules have been observed in the interstellar medium, of which about twenty are small hydrocarbons. These hydrocarbons are an important component of the interstellar chemistry as they furnish a carbon skeleton needed to build more complex molecules. However, these small hydrocarbons are easily broken apart by the UV radiation from young stars. Therefore, astronomers try to understand how these molecules are regenerated in spite of their destruction by UV radiation.. . .