Red dwarf stars are the most common kind of star in our neighbourhood, and probably in the Milky Way. Because of that, many of the Earth-like and potentially life-supporting exoplanets we’ve detected are in orbit around red dwarfs. The problem is that red dwarfs can exhibit intense flaring behaviour, much more energetic than our relatively placid Sun.
So what does that mean for the potential of those exoplanets to actually support life?
Continue reading “Stellar Flares May Not Condemn a Planet’s Habitability”
When NASA’s Voyager spacecraft visited Saturn’s moon Enceladus, they found a body with young, reflective, icy surface features. Some parts of the surface were older and marked with craters, but the rest had clearly been resurfaced. It was clear evidence that Enceladus was geologically active. The moon is also close to Saturn’s E-ring, and scientists think Enceladus might be the source of the material in that ring, further indicating geological activity.
Since then, we’ve learned a lot more about the frigid moon. It almost certainly has a warm and salty subsurface ocean below its icy exterior, making it a prime target in the search for life. The Cassini spacecraft detected molecular hydrogen—a potential food source for microbes—in plumes coming from Enceladus’ subsurface ocean, and that energized the conversation around the moon’s potential to host life.
Now a new paper uses modelling to understand Enceladus’ chemistry better. The team of researchers behind it says that the subsurface ocean may contain a variety of chemicals that could support a diverse community of microbes.
Continue reading “The Interior of Enceladus Looks Really Great for Supporting Life”
Did comets deliver the elements essential for life on Earth? It’s looking more and more like they could have. At least one comet might have, anyway: 67P/Churyumov–Gerasimenko.
A new study using data from the ESA’s Rosetta mission shows that the comet contains the life-critical element phosphorous.
Continue reading “Solid Phosphorus has been Found in Comets. This Means They Contain All the Raw Elements for Life”
In many ways, stars are the engines of creation. Their energy drives a whole host of processes necessary for life. Scientists thought that stellar radiation is needed to create compounds like the amino acid glycine, one of the building blocks of life.
But a new study has found that glycine detected in comets formed in deep interstellar space when there was no stellar energy.
Continue reading “One of the Building Blocks of Life Can Form in the Harsh Environment of Deep Space Itself. No Star Required”
In September, a team of scientists reported finding phosphine in the upper atmosphere of Venus. Phosphine can be a biomarker and is here on Earth. But it’s also present on Jupiter, where it’s produced abiotically. The discovery led to conjecture about what kind of life might survive in Venus’ atmosphere, continually producing the easily-degraded phosphine.
The authors of that study were circumspect about their own results, saying that they hope someone can determine a source for the phosphine, other than life.
Now a new study says that the original phosphine detection is not statistically significant.
Continue reading “Astronomers Challenge Recent Findings About Venus. “No Statistically Significant Detection of Phosphine””
Does it feel like all eyes are on Venus these days? The discovery of the potential biomarker phosphine in the planet’s upper atmosphere last month garnered a lot of attention, as it should. There’s still some uncertainty around what the phosphine discovery means, though.
Now a team of researchers claims they’ve discovered the amino acid glycine in Venus’ atmosphere.
Continue reading “Astronomers Report They’ve Detected the Amino Acid Glycine in the Atmosphere of Venus”
The discovery of phosphine in Venus’ atmosphere has generated a lot of interest. It has the potential to be a biosignature, though since the discovery, some researchers have thrown cold water on that idea.
But it looks, at least, like the discovery is real, and that one of NASA’s Pioneer spacecraft detected the elusive gas back in 1978. And though it’s not necessarily a biosignature, the authors of a new study think that we need to rethink the chemistry of Venus’ atmosphere.
Continue reading “Did Pioneer See Phosphine in the Clouds of Venus Decades Ago?”
In its 4.5 billion year history, Earth has had to run the gauntlet. Numerous catastrophes have imperilled the planet, from massive impacts, to volcanic conflagrations, to frigid episodes of snowball Earth. Yet life persists.
Among all of the hazards that threaten a planet, the most potentially calamitous might be a nearby star exploding as a supernova.
Continue reading “A Supernova Exploded Dangerously Close to Earth 2.5 Million Years Ago”
The detection of phosphine in Venus’ atmosphere was one of those quintessential moments in space science. It was an unexpected discovery, and when combined with our incomplete understanding of planetary science, and our wistful hopefulness around the discovery of life, the result was a potent mix that lit up internet headlines.
As always, some of the headlines were a bit of an over-reach. But that’s the way it goes.
At the heart of it all, there is compelling science. And the same, overarching question that keeps popping up: Are we alone?
Continue reading “Maybe Volcanoes Could Explain the Phosphine in Venus’ Atmosphere”
In the beginning, the universe created three elements: hydrogen, helium, and lithium. There isn’t much you can do with these simple elements, other than to let gravity collapse them into stars, galaxies, and black holes. But stars have the power of alchemy. Within their hearts, they can fuse these elements into new ones. Carbon, nitrogen, oxygen, and others, all up to the heavy element of iron. When these first stars exploded, they scattered the new elements across the cosmos, creating planets, new stars, and even us.
Continue reading “Colliding Neutron Stars Don’t Make Enough Gold to Explain What We See in the Universe”