Space enthusiasts will know – it’s easy to get caught up in a plethora of fascinating developments, from missions to the lunar surface to new discoveries in exoplanet science. But what really excites me as an astronomer right now is a largely overlooked development here on Earth that could have profound implications for how we understand the evolution of life on our planet and one of its most unique features: our oceans.
What’s to come with little fanfare Vera C. Rubin Observatory in Chile marked an important construction milestone on April 27th. workers on the Telescope We added a reflective coating to the primary mirror, giving it the ability to capture light from extremely dark objects in the night sky that we cannot currently regularly see.
With this crucial component of one of Earth’s most powerful telescopes, we can address a question that has puzzled scientists for decades: Where did our oceans come from??
Related: How did the earth get its water? Scientists are now looking for clues in “hyperactive comets.”
We know that Earth’s oceans were a key component in the evolution of life, but we are still not sure how they evolved. Some of us think our oceans were delivered to us by ice Comets And Asteroids from further out in the solar system. Likewise, recently discovered interstellar objects such as ‘Oumuamua and 2I/Borisov could tell us how oceans get to planets around other stars.
Certain chemical properties of Earth’s oceans do not resemble what we would expect if the water were present at the time of Earth’s formation. Astronomers believe that water must have been supplied after Earth formed, possibly by comets formed in the far corners of the solar system Kuiper belt or Oort cloud. However, if the European Space Agency (ESA) Rosetta mission The measured properties of the water on Comet 67P/Churyumov-Gerasimenko did not match those of our oceans.
Part of the answer may lie in learning more about one of the biggest new mysteries in the solar system: dark comets.
We recently discovered seven dark comets hiding in the asteroids near the planet Earth. These objects disguise themselves as asteroids – rocky bodies that contain no water ice. However, we noticed that the dark comets were accelerating in strange ways.
Comets are small bodies like asteroids that also contain ice like water and carbon dioxide. As a comet heats up as it approaches the sun, this ice turns into gas and is thrown from the surface, creating rocket-like acceleration and a trail of gas and dust.
These dark comets accelerate like comets, but have no visible tail to our telescopes. If they had water ice, they might have given Earth its oceans.
If dark comets actually contain water, they could be the missing link in our understanding of the origins of our oceans. It is possible that they, or dark comets like them, had water similar to our oceans in the past.
‘Oumuamua was the first large body to pass through the interior Solar system that came from another star system – our first interstellar object. Like the dark comets, ‘Oumuamua masqueraded as an asteroid because it had no obvious cometary tail, but it accelerated like a comet. We now believe that ‘Oumuamua – and the dark comets – contain ice that was invisible to us, and that this unusual ice is driving their acceleration by heating up and turning into gases.
Astronomers have discovered rocky planets that orbit other stars and could harbor oceans and life. We now know that this Exoplanetary systems have thrown so many interstellar objects like Oumuamua and Borisov into the galaxy that a tiny fraction of them must pass through our solar system. Just as dark comets could have given us our oceans, bodies like these interstellar objects could contain components essential to the development of life on rocky planets around other stars – like our Earth.
Related: 10 exoplanets that could harbor extraterrestrial life
The fact that we recently discovered both the first interstellar object and the first dark comets means that we are only at the tip of the iceberg. There are likely many more of these stealthy comets – both from interstellar space and the solar system – lurking undetected in our planetary neighborhood.
The Rubin Observatory is now one step closer to giving us access to an order of magnitude higher observation sensitivity than we have today. We will soon be able to find potentially hundreds of interstellar objects in our solar system and observe accelerations on many new dark comets.
Could dark comets and interstellar objects be the source of life? Earth-like planets? With the Ruby Observatory we have the chance to understand these entirely new populations in the solar system and possibly where we come from.
Darryl Seligman is a research associate in the Department of Astronomy at Cornell University. His research focuses primarily on theoretical and computational planetary science and astrophysics.