Space enthusiasts will know: it’s easy to get caught up in a wealth 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 explore the development of life on our planet and one of its most unique features of it: our oceans, understanding.
With little fanfare, the next one Vera C. Rubin Observatory in Chile marked an important construction milestone on April 27. Employees at the telescope has finished a reflective coating on the main mirror, giving it the ability to collect light from extremely faint objects in the night sky that we currently cannot regularly detect.
With this crucial part of what will become one of the most powerful telescopes on Earth, we can shed light on a question that has baffled scientists for decades: Where do our oceans come from??
Related: How did the earth get its water? Scientists are now looking to ‘hyperactive comets’ for clues
We know that Earth’s oceans were an important ingredient for the development of life, but we still don’t know for sure how they developed. Some of us think our oceans were delivered to us by ice Come eat And asteroids from further away in the solar system. Similarly, recently discovered interstellar objects such as ‘Oumuamua and 2I/Borisov can tell us how oceans are delivered to planets around other stars.
Certain chemical properties of Earth’s oceans do not resemble what we would expect if water were present when Earth formed. Astronomers believe that water must have been supplied after the Earth formed, possibly from comets that originate in the furthest reaches of the solar system, such as the Kuiper belt or Oortwolk. However, then the European Space Agency (ESA). Rosetta Mission Measured properties of water on the comet 67P/Churyumov-Gerasimenko, these chemical characteristics did not match those of our oceans.
Part of the answer may come from learning more about one of the greatest new mysteries in the solar system: dark comets.
We recently discovered seven dark comets lurking in asteroids close to Earth Soil. These objects disguise themselves as asteroids: rocky bodies that do not contain water ice. However, we noticed that the dark comets were accelerating in strange ways.
Comets are small bodies, such as asteroids, that also contain ices such as water and carbon dioxide. When a comet heats up as it gets closer to the sun, this ice becomes a gas and is blown off the surface, creating a rocket-like acceleration and creating a tail of gas and dust.
These dark comets accelerate like comets, but do not have a tail that is clearly visible to our telescopes. If they had water ice on them, they might have given the Earth its oceans.
If dark comets contain water, they could be the missing link in our understanding of where our oceans come from. It’s possible that they, or dark comets like them in the past, had water that resembles our oceans.
‘Oumuamua was the first large body seen through the interior solar system which came from another galaxy – our first interstellar object. Like the dark comets, ‘Oumuamua disguised itself as an asteroid because it had no obvious cometary tail, but it accelerated like a comet. We now think that ‘Oumuamua – and the dark comets – contain ice that was invisible to us and that this unusual ice is fueling their acceleration as it heats up and becomes gases.
Astronomers have discovered rocky planets orbiting other stars that could harbor oceans and life. We now know that this exoplanetary systems have flung enough interstellar objects like ‘Oumuamua and Borisov into the Milky Way that a small portion of them must pass through our solar system. Just as dark comets could have given us our oceans, bodies like these interstellar objects could carry ingredients essential for 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 we are only scratching the surface. There are likely many more of these disguised comets – both from interstellar space and from the solar system – lurking unnoticed in our planetary environment.
The Rubin Observatory is now one step closer to giving us access to orders of magnitude more observational sensitivity than we have today. Soon we may be able to find hundreds of interstellar objects in our solar system and see accelerations in many new dark comets.
Could dark comets and interstellar objects be the source of life? Earth-like planets? With the Rubin Observatory we have the opportunity to understand these entirely new populations in the solar system and possibly where we came 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.