Life on our planet appeared early in Earth’s history. Surprisingly early, since in its early youth our planet didn’t have much of the chemical ingredients necessary for life to evolve. Since prebiotic chemicals such as sugars and amino acids are known to appear in asteroids and comets, one idea is that Earth was seeded with the building blocks of life by early cometary and asteroid impacts. While this likely played a role, a new study shows that cosmic dust also seeded young Earth, and it may have made all the difference.Continue reading “Cosmic Dust Could Have Helped Get Life Going on Earth”
Aging stars that become red giants increase their luminosity and can wreak havoc on planets that were once in the star’s habitable zones. When the Sun becomes a red giant and expands, its habitable zone will move further outward, meaning Earth will likely lose its atmosphere, its water, and its life. But for planets further out, their time in the habitable zone will just begin.
Is there enough time for life to arise on these newly habitable planets?Continue reading “Dying Stars Could Have Completely New Habitable Zones”
Does life appear independently on different planets in the galaxy? Or does it spread from world to world? Or does it do both?
New research shows how life could spread via a basic, simple pathway: cosmic dust.Continue reading “Cosmic Dust Could Spread Life from World to World Across the Galaxy”
It’s a classic statement shared at many public outreach events…’we are made of stardust’. It is true enough that the human body is mostly water with some other elelments like carbon which are formed inside stars just like the Sun. It’s not just common elements like carbon though for we also have slighly more rare elements like iodine and bromine. They don’t form in normal stars but instead are generated in collisions between neutron stars! It poses an interesting question, without the neutron star merger event; ‘would we exist?’Continue reading “Could We Live Without Kilonovae?”
The number of near misses, false starts, and legitimate disasters that have befallen our species since the day we took our first upright steps all those generations ago is too large to count and could honestly take up this entire book. I’ll give us humans this much, though: we’re survivors, through and through.Continue reading “The Seeming Impossibility of Life”
We do not yet know how, where, or why life first appeared on our planet. Part of the difficulty is that “life” has no strict, universally agreed-upon definition.Continue reading “The Improbable Origins of Life on Earth”
All modern life shares a robust, hardy, efficient system of intertwined chemicals that propagate themselves. This system must have emerged from a simpler, less efficient, more delicate one. But what was that system, and why did it appear on, of all places, planet Earth?Continue reading “Early Life Was Radically Different Than Today”
The Large Interferometer for Exoplanets (LIFE) project is an ambitious plan to build a space telescope with four independent mirrors. The array would allow the individual mirrors to move closer or farther apart, similar to the way the Very Large Array (VLA) does with radio antennas. LIFE is still early in its planning stage, so it would likely be decades before it is built, but already the LIFE team is looking at ways it might discover life on other worlds. Much of this focuses on the detection of biogenic molecules in exoplanet atmospheres.Continue reading “The Next Generation LIFE Telescope Could Detect Some Intriguing Biosignatures”
The day when human beings finally set foot on Mars is rapidly approaching. Right now, NASA, the China National Space Agency (CNSA), and SpaceX have all announced plans to send astronauts to the Red Planet “by 2040”, “in 2033”, and “before 2030”, respectively. These missions will lead to the creation of long-term habitats that will enable return missions and scientific research that will investigate everything from the geological evolution of Mars to the possible existence of past (or even present) life. The opportunities this will create are mirrored only by the challenges they will entail.
One of the greatest challenges is ensuring that crews have access to water, which means that any habitats must be established near an underground source. Similarly, scientists anticipate that if there is still life on Mars today, it will likely exist in “briny patches” beneath the surface. A possible solution is to incorporate a system for large-scale water mining operations on Mars that could screen for lifeforms. The proposal, known as an Agnostic Life Finding (ALF) system, was one of thirteen concepts selected by NASA’s Innovative Advanced Concept (NIAC) program this year for Phase I development.Continue reading “NASA Selects New Technology to Help Search for Life on Mars”
On October 19th, 2017, astronomers with the Pan-STARRS survey detected an interstellar object (ISO) passing through our Solar System for the first time. The object, known as 1I/2017 U1 Oumuamua, stimulated significant scientific debate and is still controversial today. One thing that all could agree on was that the detection of this object indicated that ISOs regularly enter our Solar System. What’s more, subsequent research has revealed that, on occasion, some of these objects come to Earth as meteorites and impact the surface.
This raises a very important question: if ISOs have been coming to Earth for billions of years, could it be that they brought the ingredients for life with them? In a recent paper, a team of researchers considered the implications of ISOs being responsible for panspermia – the theory that the seeds of life exist throughout the Universe and are distributed by asteroids, comets, and other celestial objects. According to their results, ISOs can potentially seed hundreds of thousands (or possibly billions) of Earth-like planets throughout the Milky Way.Continue reading “Since Interstellar Objects Crashed Into Earth in the Past, Could They Have Brought Life?”