The first ever molecule formed in the universe — helium hydride, or HeH+ — has been detected in space for the first time, a new study reports.

The elusive molecule was found in the young planetary nebula NGC 7027, where HeH+ is being formed by a white dwarf star.

Around 13 billion years ago this molecular bond would have formed as positively charged particles combined with hydrogen atoms in the early cooling universe.

The discovery was made using a telescope which is carried up into the Earth's atmosphere, and above its signal-damping effects, by a special aeroplane. 

The finding, led by researchers from the Max Planck Institute for Radio Astronomy,  brings to the end a search for the molecule which began back in the late 1970s. 

As the early universe cooled below 4,000°K (6740°F/3,727°C) some 13 billion years ago, the light elements produced from the Big Bang began to combine.

It is believed that neutral helium atoms and ionised hydrogen - or protons - reacted to form ions of HeH+.

This would have been the first type of molecular bond to ever form in the universe.

HeH+ would have ultimately gone on to react with neutral hydrogen, paving the way to the formation of molecular hydrogen — and the beginning of the universe as we know it today.

Despite both its significance in the history of the universe, and having been first successfully synthesised in the laboratory in 1925, attempts to detect the molecule out in the universe itself had previously been to no avail.

The hunt began in the late seventies, when chemical models suggested that HeH+ might exist in detectable amounts in nearby interstellar nebulae. 

'The chemistry of the Universe began with HeH+,' said lead author and astrophysicist Rolf Güsten, of the Max Planck Institute for Radio Astronomy (MPIfR), in Germany.

'The lack of definitive evidence of its very existence in interstellar space has been a dilemma for astronomy for a long time.'

The failure to spot naturally-formed HeH+ out in space had been casting doubt on the understanding that had been developed of the chemical processes that were thought to have formed it in the early individual.

However, past hunts were only unsuccessful because the available spectrometer technology used all had too limited resolving power at the relevant wavelengths in which the molecule would be found. 

With new technology, however, the search has finally come to an end. 

Dr Güsten and colleagues from the MPIfR joined forces with researchers from Johns Hopkins University in Baltimore, both the Universities of Cologne and Applied Sciences Bonn-Rhein-Sieg in Germany, as well as the Institute of Millimetre Radioastronomy in France.

The international team made use of the high-resolution German Receiver for Astronomy at Terahertz Frequencies (GREAT) spectrometer to detect the infrared signals emitted by helium hydride ions.

The GREAT device is located on-board the Stratospheric Observatory for Infrared Astronomy (SOFIA), a modified Boeing 747 aircraft that carries a reflecting telescope.

The scientific research craft is operated by NASA and the German Aerospace Centre.

SOFIA is capable of flying above the majority of the water vapour in the atmosphere, the presence of which blocks some infrared signals from reaching the ground.

'With recent advancements in terahertz technologies is has now become possible to perform high-resolution spectroscopy at the required far-infrared wavelength', Dr Güsten added.

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