Space and astronomy news
A team of astrophysicists has discovered a binary pair of ultra-cool dwarfs so close together that they look like a single star. They’re remarkable because they only take 20.5 hours to orbit each other, meaning their year is less than one Earth Day. They’re also much older than similar systems.
Continue reading “Binary Dwarf Stars Found Orbiting Each Other Every 20 Hours. They Were Once Almost Touching”
Future historians might look back on this time and call it the ‘exoplanet age.’ We’ve found over 5,000 exoplanets, and we’ll keep finding more. Next, we’ll move beyond just finding them, and we’ll turn our efforts to finding biosignatures, the special chemical fingerprints that living processes imprint on exoplanet atmospheres.
But there’s more to biosignatures than atmospheric chemistry. On a planet with lots of plant life, light can be a biosignature, too.
Continue reading “Worlds Bustling With Plantlife Should Shine in a Detectable Wavelength of Infrared”
Astronomers are very interested in the Habitable Zone of distant stars, which is the orbital radius where liquid water, and therefore potentially life, can exist on a planet in that region. But life itself changes the characteristics of a planet. New research suggestions that life is even capable of redefining what the Habitable Zone can mean.
Continue reading “How Life Reshapes the Habitable Zone”
For planet-hunters, finding an Earth-sized exoplanet must be special. NASA estimates there are about 100 billion planets in the Milky Way, but the large majority of the 5,000+ exoplanets we’ve found are extremely inhospitable. So finding one that’s similar to ours is kind of comforting.
In this case, it’s even more interesting because it’s the second Earth-sized planet orbiting the same star.
Continue reading “TESS has Found A Second Earth-Sized World in This System. Exoplanet Science is Maturing”
Astronomers are keenly interested in red dwarfs and the planets that orbit them. Up to 85% of the stars in the Milky Way could be red dwarfs, and 40% of them might host Earth-like exoplanets in their habitable zones, according to some research.
But there are some problems with their potential habitability. One of those problems is tidal locking.
Continue reading “Are Planets Tidally Locked to Red Dwarfs Habitable? It’s Complicated”
Our understanding of habitability relies entirely on the availability of liquid water. All life on Earth needs it, and there’s every indication that life elsewhere needs it, too.
Can planets with frozen surfaces somehow have enough water to sustain life?
Continue reading “Could Life Survive on Frigid Exo-Earths? Maybe Under Ice Sheets”
A team of astronomers has found two Super-Earths orbiting a red dwarf about 114 light-years away. The star, named LP 890-9, is the second coolest star found that hosts planets. Both the planets are likely temperate, and one of them “… is the second-most favourable habitable-zone terrestrial planet known so far,” according to the paper presenting the results.
Continue reading “Astronomers Have Found Two Temperate Super-Earths Orbiting a Nearby Red Dwarf”
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?”
The Curiosity rover has now reached its primary target on Mount Sharp on Mars, the mountain in the middle of Gale Crater the rover has been climbing since 2014. This target is not the summit, but a region over 600 meters (2,000 feet) up the mountain that planetary geologists have long anticipated reaching.
Known as the “sulfate-bearing unit,” the region is a boundary between the rocks that saw a lot of water in their history and those that didn’t; a possible shoreline, if you will. That boundary is already providing insights into Mars’ transition from a wet planet to dry, filling in a key gap in the understanding of the planet’s history.
Continue reading “Curiosity Arrives in a Salty Region of Mars. Was it Left Over From a Dying Sea?”
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”