Astronomers have made another super discovery. They have found evidence of what they think was the first ever molecule formed in the universe! This is the helium hydride ion (HeH+). Scientists were able to create this in the lab as long ago as 1925. However they were unable to find this molecule in space. They have finally found it in our own galaxy, the Milky Way. The HeH+ molecule was discovered in a constellation called Cygnus about 3000 light years away.
How Did They Find It? Astronomers thought that perhaps this molecule could be detected in nebulas, or clouds of gas and dust that are produced just before a star explodes in a supernova. These are the closest conditions we can think of that approximate the environment after the Big Bang and the creation of the universe. NASA used a plane called SOFIA (Stratospheric Observatory For Infrared Astronomy), that carries a special telescope and flies above the lower layers of the atmosphere, to investigate a nebula called NGC 7027. This instrument was finally able to detect helium hydride, according to results that have been published in a scientific journal last week.
A bit of background: We live in a young universe: Right after the Big Bang, the universe was very hot and dense, and space contained only a few atoms, mostly hydrogen and helium. The Earth slowly cooled and the temperatures dropped below 3700 degrees Celsius. In this environment, almost one lakh years after the Big Bang, the helium and hydrogen atoms combined for the very first time, creating helium hydride. The conditions of the early universe did not allow this molecule to last very long, but it is thought that the beginning of the modern universe began with the formation of the helium hydride ion. This event is called the Dawn of Chemistry.
Why was it difficult to find? The Earth’s atmosphere prevented detection of the molecule. To find it, the astronomers flew the SOFIA plane above the Earth’s surface and looked for the molecule.
Vaijayanti is a writer, a nature enthusiast and an amateur wildlife photographer. She hopes her virtual pen and lens can make the world a better place.