Ethyl formate is an ester formed when ethanol (an alcohol) reacts with formic acid (a carboxylic acid). Ethyl formate has the characteristic smell of rum and is also partially responsible for the flavor of raspberries. It occurs naturally in the body of ants and in the stingers of bees.
This unlikely discovery was made by astronomers studying interstellar objects for new molecules. They had the IRAM radio telescope trained on Sagittarius B2 – a gas cloud at the centre of the Milky Way galaxy – when they found a chemical called ethyl formate. This is one of the aroma compounds that creates the sweet scents of fruit, wine and flowers, and it smells a lot like rum. It is also the chemical that gives raspberries their distinctive flavour.
Ethyl formate is made from ethanol – a common molecule found in star-forming gas clouds – with formic acid, which is a mix of hydrogen, oxygen and carbon atoms. It’s visible to radio telescopes because ethyl formate molecules absorb the radiation from the stars and re-radiate it at radio wavelengths. Ethyl formate molecules are some of the largest molecules ever found in space and are among the building blocks of amino acids, which are vital for life as we know it.
Even though Sagittarius B2 is extremely dense as far as star-forming regions go, it still only has around 3,000 molecules per cubic centimetre, compared to around 25 million trillion molecules per cubic centimetre in the air that we breathe on Earth. So, even if you could breathe in the nebula, it would sadly be too rarefied to actually smell the rum or taste the raspberries.
Picture Credit : Google