Wonders of the Universe

THE ORIGIN OF LIFE

This seemingly ordinary piece of rock is anything but; this asteroid fragment is older than any rock on Earth and is one of the thousands of meteorites that fall onto our planet every year.

There are thousands of asteroids in our solar system, mostly within an asteroid belt that formed 4,568 million years ago, and on average one meteorite falls to Earth once a month. However, each and every one discovered is hugely important, regardless of its size, as these asteroid pieces give us a real insight into what forms the building blocks of life.

At first sight the graph opposite – depicting the spectrum of the light from the Orion Nebula (taken from the Herschel Space Observatory Telescope) – looks rather uninspiring, but the information that it contains is in fact fascinating. This illustration reveals that the Orion Nebula is not just a cloud of elements; there is complex chemistry happening out there deep in space.

Just like the black lines in the spectrum of the Sun, the peaks on this graph correspond to particular chemical elements, but some of these peaks derive from complex molecules – there is water in the nebula, and sulphur dioxide. Perhaps more surprisingly, there are also complex carbon compounds – methanol, hydrogen cyanide, formaldehyde and dimethyl ether. This is direct evidence for complex carbon chemistry occurring in deep space. This is tremendously exciting because it means that we are seeing the beginnings of the chemistry of life in a vast cloud of interstellar gas.

The connection doesn’t end there; we may be connected to the chemistry out there in space even more directly. The photo opposite is of a meteorite, a piece of rock that fell to Earth from somewhere out in the depths of the Solar System. It is almost certainly older than any rock on Earth because it was formed from the primordial dust cloud, the nebula that collapsed to form the Sun and the planets five billion years ago. When looking inside this ancient rock we discovered something incredibly interesting: it was found to contain amino acids, the building blocks of proteins, which in turn are the building blocks of life. This strongly suggests there was very complex carbon chemistry happening out there in space, forming the building blocks of life, over four and a half billion years ago. It raises the intriguing prospect that the first amino acids on Earth may have formed in the depths of space and been delivered to our planet by meteorites.

ORION’S MOLECULAR MAKE-UP: This detailed spectrum, obtained by ESA’s Herschel Space Observatory, shows the fascinating chemical fingerprints of potential life-enabling organic molecules in the Orion Nebula.

The fundamental building blocks of life may have formed in the depths of space and been delivered to our planet by meteorites.

This is one more beautiful piece of evidence that forces us to think differently about those twinkling lights and smudges of gas and dust in the sky. When we look out into space we are looking at our place of birth. We truly are children of the stars, and written into every atom and molecule of our bodies is the history of the Universe, from the Big Bang to the present day

Our story is the story of the Universe. Every piece of every one and every thing you love, of every thing you hate, of every thing you hold precious, was assembled in the first few minutes of the life of the Universe, and transformed in the hearts of stars or created in their fiery deaths. When you die those pieces will be returned to the Universe in the endless cycle of death and rebirth. What a wonderful thing to be a part of that universe – and what a story. What a majestic story!

Supernovae are the long-awaited spectacles of the skies. It is in the death of old stars that new ones are born, and their demise plays a crucial part of the endless cycle of death and rebirth that occurs right across our universe.