water worlds Archives

February 27, 2024February 27, 2024 by Evan Gough

Some Intelligent Civilizations Will Be Trapped on their Worlds

With thousands of exoplanets discovered so far, astronomers are learning how different planets can be. What if intelligent alien civilizations arise on extremely different habitable worlds? Some civilizations could develop space exploration technologies, but others would be trapped underwater, under ice, or in enormous gravity wells. How could they escape? Image Credit: DALL-E

Evolution has produced a wondrously diverse variety of lifeforms here on Earth. It just so happens that talking primates with opposable thumbs rose to the top and are building a spacefaring civilization. And we’re land-dwellers. But what about other planets? If the dominant species on an ocean world builds a technological civilization of some sort, would they be able to escape their ocean home and explore space?

February 13, 2024February 13, 2024 by Laurence Tognetti

Saturn’s “Death Star Moon” Mimas Probably has an Ocean Too

Saturn's moon, Mimas, captured by NASA's Cassini spacecraft in 2010. (Credit: NASA/JPL-Caltech/Space Science Institute)

A recent study published in Nature presents a groundbreaking discovery that Saturn’s moon, Mimas, commonly known as the “Death Star” moon due to its similarities with the iconic Star Wars space station, possesses an internal ocean underneath its rocky crust. This study was conducted by an international team of researchers and holds the potential to help planetary geologists better understand the conditions for a planetary body to possess an internal ocean, which could also possess the conditions for life as we know it. While Mimas was photographed on several occasions by NASA’s Cassini spacecraft, including a close flyby in February 2010, what was the motivation behind this recent study regarding finding an internal ocean on Mimas?

December 6, 2023December 6, 2023 by Evan Gough

Astronomers Calculate Which Exoplanets Are Most Likely to Have Water

This illustration shows what the hot rocky exoplanet TRAPPIST-1 b could look like. A new method can help determine what rocky exoplanets might have large reservoirs of subsurface water. Credits: NASA, ESA, CSA, J. Olmsted (STScI)

Astronomers know of about 60 rocky exoplanets orbiting in the habitable zones of their stars. When they try to determine how habitable these planets might be, detecting water in their atmospheres plays a huge role. But what if there was another way of measuring the water content in these worlds?

Researchers are developing a way of modelling these worlds to determine how much water they have.

February 8, 2023February 9, 2023 by Laurence Tognetti

Astronomers still scratching their heads over population of ocean-world exoplanets

Artist rendition of a potential water-world exoplanet that might support advanced civilizations. Such life could advertise its existence via technosignatures from industrial or other activities. (Credit: ESA / Hubble / M. Kornmesser) — Artist rendition of a potential water-world exoplanet that might support life. Scientists could determine whether to explore this world based on its planetary entropy production. (Credit: ESA / Hubble / M. Kornmesser)

In a recent study submitted to The Astrophysical Journal Letters, an international team of researchers led by the University of California, Los Angeles (UCLA) examine the potential for water-worlds around M-dwarf stars. Water-worlds, also known as ocean worlds, are planets that possess bodies of liquid water either directly on its surface, such as Earth, or somewhere beneath it, such as Jupiter’s moon, Europa and Saturn’s moon, Enceladus.

December 19, 2022January 28, 2023 by Matt Williams

Hubble and Spitzer Team up to Find a Pair of Waterworld Exoplanets

Artist’s impression of a water world, where half of its mass consists of water. Just like our Moon, the planet is bound to its star by tidal forces and always shows the same face to its host star. Credit: Pilar Montañés

As of December 19th, 2022, 5,227 extrasolar planets have been confirmed in 3,908 systems, with over 9,000 more awaiting confirmation. While most of these planets are Jupiter- or Neptune-sized gas giants or rocky planets many times the size of Earth (Super-Earths), a statistically significant number have been planets where water makes up a significant part of their mass fraction – aka. “water worlds.” These planets are unlike anything we’ve seen in the Solar System and raise several questions about planet formation in our galaxy.

In a recent study, an international team led by researchers from the University of Montreal’s Institute for Research on Exoplanets (iREx) found evidence of two water worlds in a single planetary system located about 218 light-years away in the constellation Lyra. Based on their densities, the team determined that these exoplanets (Kepler-138c and Kepler-138d) are lighter than rocky “Earth-like” ones but heavier than gas-dominated ones. The discovery was made using data from NASA’s now-retired Spitzer Space Telescope and the venerable Hubble Space Telescope.

November 16, 2022November 16, 2022 by Brian Koberlein

Mapping the Interiors of Meteorites to Learn how Earth got its Water

A composite image of Earth as a watery world. Credit: Reto Stöckli, Robert Simmon, MODIS/NASA

Earth is a strange world. A warm, rocky planet covered with oceans of liquid water. This strangeness is central to life on Earth, but it has been a longstanding puzzle for astronomers. Just why is our planet wet while other terrestrial worlds are dry? Where did all of Earth’s water come from?

September 14, 2022September 14, 2022 by Matt Williams

There Could be as Many Water Worlds as Earths in the Milky Way

Artist’s impression of the strange landscape of a water world. Credit: Pilar Montañés

On July 12th, 2022, NASA released the first images acquired by the James Webb Space Telescope, which were taken during its first six months of operation. Among its many scientific objectives, Webb will search for smaller, rocky planets that orbit closer to their suns – especially dimmer M-type (red dwarf) stars, the most common in the Universe. This will help astronomers complete the census of exoplanets and gain a better understanding of the types of worlds that exist out there. In particular, astronomers are curious about how many terrestrial planets in our galaxy are actually “water worlds.”

These are rocky planets that are larger than Earth but have a lower density, which suggests that volatiles like water make up a significant amount (up to half) of their mass-fraction. According to a recent study by researchers from the University of Chicago and the Instituto de Astrofísica de Canarias (IAC), water worlds may be just as common as “Earth-like” rocky planets. These findings bolster the case for exoplanets that are similar to icy moons in the Solar System (like Europa) and could have significant implications for future exoplanet studies and the search for life in our Universe.

June 28, 2022June 28, 2022 by Evan Gough

Water Worlds Could Have Plumes of Nutrients Carried up From Down Below

This reprocessed colour view of Jupiter’s moon Europa was made from images taken by NASA's Galileo spacecraft in the late 1990s. Credit: NASA/JPL-Caltech

Earth’s oceans are one huge, uniform electrolyte solution. They contain salt (sodium chloride) and other nutrients like magnesium, sulphate, and calcium. We can’t survive without electrolytes, and life on Earth might look very different without the oceans’ electrolyte content. It might even be non-existent.

On Earth, electrolytes are released into the oceans from rock by different processes like volcanism and hydrothermal activity.

Are these life-enabling nutrients available on water worlds?

July 28, 2021July 28, 2021 by Andy Tomaswick

Water Vapour has Been Discovered at Ganymede

Ganymede has been getting alot of attention lately. It was the co-star of a video from Juno recently, and now scientists found something to make it an even more intriguing place visit – water vapor.

November 5, 2018March 24, 2019 by Matt Williams

Exoplanets Will Need Both Continents and Oceans to Form Complex Life

Artist's concept of Earth-like exoplanets, which (according to new research) need to strike the careful balance between water and landmass. Credit: NASA

When it comes to the search for extra-terrestrial life, scientists have a tendency to be a bit geocentric – i.e. they look for planets that resemble our own. This is understandable, seeing as how Earth is the only planet that we know of that supports life. As result, those searching for extra-terrestrial life have been looking for planets that are terrestrial (rocky) in nature, orbit within their stars habitable zones, and have enough water on their surfaces.

In the course of discovering several thousand exoplanets, scientists have found that many may in fact be “water worlds” (planets where up to 50% of their mass is water). This naturally raises some questions, like how much water is too much, and could too much land be a problem as well? To address these, a pair of researchers from the Harvard Smithsonian Center for Astrophysics (CfA) conducted a study to determine how the ratio between water and land masses can contribute to life.

Continue reading “Exoplanets Will Need Both Continents and Oceans to Form Complex Life”