Earth is about 29% land and 71% oceans. How significant is that mix for habitability? What does it tell us about exoplanet habitability?Continue reading “What’s the Best Mix of Oceans to Land for a Habitable Planet?”
There’s an ocean of human-made garbage floating through Earth’s seas. From plastic straws to beverage bottles and food wrappers, the ocean waters are this planet’s fastest-growing junkyard. Some of the plastic gets ground into little beads called microplastics, and ends up in the food chain, with humans at the top. For that reason, and many others, the European Space Agency is tracking ocean-bound plastics through the auspices of the MARLISAT project. It’s one of 25 efforts created to identify and trace marine litter as it moves through the world’s waterways. The ultimate goal is to help countries reduce ocean litter, particularly plastics.Continue reading “Satellites are Tracking Rivers of Garbage Flowing Across the Oceans”
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?Continue reading “Water Worlds Could Have Plumes of Nutrients Carried up From Down Below”
Jupiter’s moon Europa is a prime candidate in the search for life. The frozen moon has a subsurface ocean, and evidence indicates it’s warm, salty, and rich in life-enabling chemistry.
New research shows that the moon is pulling oxygen down below its icy shell, where it could be feeding simple life.Continue reading “Europa Could be Pulling Oxygen Down Below the Ice to Feed Life”
Data from the Cassini mission keeps fuelling discoveries. The latest discovery is that Saturn’s tiny moon Mimas may have an internal ocean. If it does, the moon joins a growing list of natural satellites in our Solar System that may harbour liquid water under their surfaces.Continue reading “Even Tiny Mimas Seems to Have an Internal Ocean of Liquid Water”
You could say that the study of extrasolar planets is in a phase of transition of late. To date, 4,525 exoplanets have been confirmed in 3,357 systems, with another 7,761 candidates awaiting confirmation. As a result, exoplanet studies have been moving away from the discovery process and towards characterization, where follow-up observations of exoplanets are conducted to learn more about their atmospheres and environments.
In the process, exoplanet researchers hope to see if any of these planets possess the necessary ingredients for life as we know it. Recently, a pair of researchers from Northern Arizona University, with support from the NASA Astrobiology Institute’s Virtual Planetary Laboratory (VPL), developed a technique for finding oceans on exoplanets. The ability to find water on other planets, a key ingredient in life on Earth, will go a long way towards finding extraterrestrial life.Continue reading “A Technique to Find Oceans on Other Worlds”
At first glance, Jupiter’s moon Europa doesn’t seem much like Earth. It’s a moon, not a planet, and it’s covered in ice. But it does have one important thing in common with Earth: a warm, salty ocean.
Now there’s even more evidence that Europa’s sub-surface ocean is habitable.Continue reading “More Evidence that Europa’s Oceans Could be Habitable”
It seems unlikely that an ocean could persist on a world that never gets closer than 30 astronomical units from the Sun. But that’s the case with Pluto. Evidence shows that it has a sub-surface ocean between 100 to 180 km thick, at the boundary between the core and the mantle. Other Kuiper Belt Objects may be similar.
But time might be running out for these buried oceans, which will one day turn to ice.Continue reading “Pluto and Other Kuiper Belt Objects Started Out With Water Oceans, and Have Been Slowly Freezing Solid for Billions of Years”
We’ve found thousands and thousands of exoplanets now. And spacecraft like TESS will likely find thousands and thousands more of them. But most exoplanets are gassy giants, molten hell-holes, or frozen wastes. How can we find those needles-in-the-haystack habitable worlds that may be out there? How can we narrow our search?
Well, first of all, we need to find water. Oceans, preferably, since that’s where life began on Earth. And according to a new study, those oceans need to circulate in particular ways to support life.Continue reading “Ocean Circulation Might Be the Key to Finding Habitable Exoplanets”
Evidence from an ancient section of the Earth’s crust suggest that Earth was once a water-world, some three billion years ago. If true, it’ll mean scientists need to reconsider some thinking around exoplanets and habitability. They’ll also need to reconsider their understanding of how life began on our planet.Continue reading “3 Billion Years Ago, the World Might Have Been a Waterworld, With No Continents At All”