Page "Stephan's Quintet" Paragraph 5

Perhaps even more unexpected is the discovery of very powerful molecular hydrogen signals from the shock wave, seen by the NASA Spitzer Space Telescope which detects infrared radiation.

The molecular hydrogen emission, which is seen through infrared spectral analysis using the Spitzer Space Telescope is one of the most turbulent formations of molecular hydrogen ever seen, and the strongest emission originates near the center of the green area in the visible light picture discussed earlier.

This phenomenon was discovered by an international team led by scientists at the California Institute of Technology and includes scientists from Australia, Germany and China.

The detection of molecular hydrogen from the collision was initially unexpected because the hydrogen molecule is very fragile and is easily destroyed in shock waves of the kind expected in Stephan's Quintet.

However, one solution is that when a shock front moves through a cloudy medium like the center of the group, millions of smaller shocks are produced in a turbulent layer, and this can allow molecular hydrogen to survive.

Most notable is the fact that this collision can help provide a view into what happened in the postulated beginning of the universe some 14 billion years ago, since shocked molecular hydrogen is likely to be present in the early universe.