Water covers around 70% of Earth’s surface, but the question of where it actually comes from is still debated among scientists.

For a long time, the origins of water on our planet have been a bit of a puzzle.

However, a recent discovery sheds new light on where Earth’s water may have started: researchers now claim to have traced its origins back to the earliest moments of the universe.

Water’s Formation After the Big Bang

A team of scientists from the University of Portsmouth has made a groundbreaking claim that water first began to form in the aftermath of supernova explosions, occurring about 100 to 200 million years after the Big Bang.

These findings suggest that the key ingredients for life, like water, were already in place much earlier than we previously thought.

The researchers used computer simulations to show that water formed in the debris of supernova explosions, which occurred when the first stars in the universe died and collapsed.

As oxygen from these explosions cooled and mixed with surrounding hydrogen, water began to form in the leftover material.

This debris, which clumped together in dense cores, is also likely the place where the first planets began to take shape.

Dr. Daniel Whalen, along with his co-authors, explained that their research not only shows that a key ingredient for life was present just 100-200 million years after the Big Bang, but that water might have been a significant component of the first galaxies.

The Ingredients of Water: Hydrogen and Oxygen

Water is made up of two simple ingredients: hydrogen and oxygen.

Hydrogen formed in the minutes following the Big Bang, when superheated particles cooled and combined into atoms, creating elements like hydrogen, helium, and lithium.

However, oxygen, being a heavier element, couldn’t have been formed in the same way.

Instead, it had to be created through nuclear reactions in stars.

About 100 million years after the Big Bang, clouds of primordial hydrogen and helium came together under gravity.

As these clouds grew denser, the pressure at their cores became intense enough to trigger nuclear fusion, transforming them into stars and bringing the first light to the universe.

When these stars exhausted their hydrogen fuel, they collapsed into supernova explosions, reaching temperatures of around 1 billion degrees Celsius (1.8 billion degrees Fahrenheit).

This process fused the hydrogen and helium into heavier elements, including oxygen.

How Water Formed in the Universe

Water, as we know it, is made of hydrogen and oxygen.

The hydrogen existed from the early moments of the universe, but oxygen only formed later in the life cycle of stars.

These massive explosions created by dying stars not only produced oxygen but also led to the formation of water.

The heat from the supernovae enabled the hydrogen and oxygen atoms to clump together, eventually forming water in the debris surrounding the explosion.

Over millions of years, this process continued, creating large amounts of water that might have survived and contributed to the formation of the first galaxies.

Simulating the Supernovae’s Impact

In their study, the researchers modeled the aftermath of two supernova explosions—one from a star 13 times the mass of the Sun and the other from a star 200 times its mass.

These simulations showed that each explosion produced significant amounts of oxygen and water.

The smaller supernovae produced tiny amounts of water, but even these small amounts could have had a lasting impact.

Meanwhile, the larger explosion produced much greater amounts of water, and after just a few million years, it could have contributed to the early formation of galaxies.

The water formed in these supernova explosions could have been one of the key components in the creation of the first galaxies.

Over time, this water could have been part of the material that formed the first planets.

The Role of Water in Planet Formation

What makes this discovery so intriguing is that it could help explain how water arrived on planets like Earth.

The dense molecular clouds, where water formed in abundance, are also where protoplanetary disks likely began to take shape.

These disks are swirling clouds of dust that eventually form planets and stars, like our Sun.

In some of these disks, water levels could have been significantly higher than in other areas of the universe.

The researchers found that the amount of water in these disks could have been 10-30 times greater than what is found in diffuse clouds within our Milky Way.

With such high levels of water, it’s possible that planets with liquid water could have formed shortly after the first supernovae.

This discovery suggests that the conditions needed for life may have been set in motion much earlier than previously believed—billions of years before Earth was even formed.

A Glimpse Into the Search for Life

The discovery of water’s ancient origins is a significant step in humanity’s ongoing search for alien life. Over the years, several breakthroughs have brought us closer to understanding the potential for life elsewhere in the universe. These include:

The Discovery of Pulsars: In 1967, British astronomer Dame Jocelyn Bell Burnell discovered the first pulsar, a rotating, magnetized neutron star. Some initially thought the signals might have come from extraterrestrial civilizations.
The ‘Wow!’ Signal: In 1977, a powerful radio signal from deep space caused astronomer Dr. Jerry Ehman to exclaim “Wow!” It was never traced to a known source, sparking rumors that it might have been a message from aliens.
Martian Microbes: In 1996, scientists announced the discovery of possible signs of life in a meteorite from Mars, though further analysis raised doubts.
Tabby’s Star: Discovered in 2005, this star baffled scientists with its unusual dimming patterns, leading some to speculate about alien megastructures. However, more recent studies suggest dust clouds might be responsible.
Exoplanets in the Goldilocks Zone: In 2017, astronomers identified a system with seven Earth-like planets that might support life. The discovery of water on these planets raises the possibility that life could already be present.