Carbon is critical to life, as far as we know. So anytime we detect a strong carbon signature somewhere like Mars, it could indicate biological activity.
Does a strong carbon signal in Martian rocks indicate biological processes of some type?
Continue reading “Curiosity Sees a Strong Carbon Signature in a Bed of Rocks”
Without phosphorus, there’s no life. It’s a necessary part of DNA, RNA, and other biological molecules like ATP, which helps cells transport energy. But any phosphorus that was present when Earth formed would’ve been sequestered in the center of the molten planet.
So where did phosphorus come from?
It might have come from cosmic dust.
Continue reading “Did Cosmic Dust Deliver the Phosphorus Needed for Life?”
Author’s note – this article was written with Dr. Vincent Kofman, a scientist at NASA’s Goddard Space Flight Center (GSFC), working in the Sellers Exoplanet Environments Collaboration (SEEC), and the lead author on the research it discusses.
Thousands of exoplanets have been discovered in the recent decades. Planet hunters like TESS and Kepler, as well as numerous ground-based efforts, have pushed the field and we are starting to get a total number of planets that will allow us to perform effective statistical analysis on some of them.
Not only do the detected number of planets show us how common they are; it exposes our lack of understanding about how planets form, what conditions are present, and when planets may be habitable. The transit detection of an exoplanet primarily yields the orbital period, or the length of a year on the planet, and the relative size of the planet with respect to the star. The next steps are to characterize the planet. This usually requires follow up studies, using different observational strategies and more powerful telescopes.
Continue reading “How To Search the Chemical Makeup of Exoplanet Atmospheres for Hints at Their History”
This is our Great Question: How did life begin on Earth? Anyone who says they have the answer is telling tall tales. We just don’t know yet.
While a definitive answer may be a long way off—or may never be found—there are some clever ways to nibble at the edges of that Great Question. A group of researchers at Kobe University in Japan are taking their own bites out of that compelling question with a question of their own: Did the heat from asteroid impacts help life get started?
Continue reading “Did Asteroid Impacts Provide Both the Heat and Raw Ingredients to Enable Life?”
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”
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?”
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”
Astronomers have a dark energy problem. On the one hand, we’ve known for years that the universe is not just expanding, but accelerating. There seems to be a dark energy that drives cosmic expansion. On the other hand, when we measure cosmic expansion in different ways we get values that don’t quite agree. Some methods cluster around a higher value for dark energy, while other methods cluster around a lower one. On the gripping hand, something will need to give if we are to solve this mystery.
Continue reading “The Chemicals That Make Up Exploding Stars Could Help Explain Away Dark Energy”
Despite all we know about the formation and evolution of the Universe, the very early days are still kind of mysterious. With our knowledge of physics we can shed some light on the nature of the earliest stars, even though they’re almost certainly long gone.
Now a new discovery is confirming what scientists think they know about the early Universe, by shedding light on a star that’s still shining.
Continue reading “Traces of One of the Oldest Stars in the Universe Found Inside Another Star”