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Can rocky exoplanets orbiting stars smaller than our Sun support life as we know it? This is what a recent study published in Nature Communications hopes to address as an international team of researchers examined the atmospheric stability of exoplanets orbiting M-dwarf stars, which typically range from 7.5 percent to 50 percent of our Sun’s mass and surface temperatures of approximately 3,500 degrees Celsius (6,300 degrees Fahrenheit) with our Sun boasting surface temperatures of approximately 5,000 degrees Celsius (9,000 degrees Fahrenheit). This study holds the potential to help astronomers better understand the conditions for finding life beyond Earth and where we can find it.

For the study, the researchers examined TRAPPIST-1, which is an M-dwarf star located approximately 40 light-years from Earth while boasting seven rocky exoplanets, several of which orbit within its star’s habitable zone (HZ). Using computer models, the team simulated the formation and evolution of the orbiting exoplanets to ascertain if their individual atmospheres could remain stable over time to form a habitable environment. In the end, the team found that the exoplanets that orbit close to their star likely do not possess stable atmospheres, but found promising results for exoplanets orbiting farther out, specifically TRAPPIST-1 e.

“One of the most intriguing questions right now in exoplanet astronomy is: Can rocky planets orbiting M-dwarf stars maintain atmospheres that could support life?” said Dr. Joshua Krissansen-Totton, who is an assistant professor of Earth and space sciences at the University of Washington and lead author of the study. “Our findings give reason to expect that some of these planets do have atmospheres, which significantly enhances the chances that these common planetary systems could support life.”

In a remarkable encounter off the coast of Alaska, human scientists had what they describe as a “conversation” with a humpback whale named Twain. Dr. Brenda McCowan from the University of California Davis was at the heart of this unexpected exchange.

Dr. McCowan and her team, known as Whale-SETI, have been studying how humpback whales communicate. They’re aiming to understand whale communication systems to help in the search for life beyond Earth.

Using an underwater speaker, the team played a recorded humpback “contact” call into the ocean. To their astonishment, Twain approached their boat and began responding.

Are we alone in the universe? Are there other technological civilizations out there and how can we find them? This is what a recent preprint submitted to The Astronomical Journal hopes to address as a team of researchers led by Penn State University investigated new methods for detecting radio signals from extraterrestrial technological civilizations (ETIs). This study holds the potential to help researchers better understand and develop more efficient methods for detecting radio signals from ETIs and how we can continue to improve these methods.

For the study, instead of attempting to detect radio signals directed at Earth from an ETI, the researchers focused on radio signals that could potentially be traveling between planets, known as planet-planet occultations (PPOs). The team tested this method on the TRAPPIST-1 system, which boasts seven approximate Earth-sized worlds, and at least three orbiting within its star’s habitable zone (HZ). After using computer models to estimate the number of potential PPOs that could be found within the system, the researchers used the Allen Telescope Array (ATA) to scan the TRAPPIST-1 system for 28 hours with the goal of detecting radio signals emanating from ETIs. In the end, the researchers detected no signals, but this study opens the door for better understanding how to develop and improve methods for detecting ETI radio signals.

“This research shows that we are getting closer to technology and methods that could detect radio signals similar to the ones we send into space,” said Nick Tusay, who is a PhD student in the Department of Astronomy and Astrophysics at Penn State and lead author of the study. “Most searches assume a powerful signal, like a beacon intended to reach distant planets, because our receivers have a sensitivity limit to a minimum transmitter power beyond anything we unintentionally send out. But, with better equipment, like the upcoming Square Kilometer Array, we might soon be able to detect signals from an alien civilization communicating with its spacecraft.”

Scientists found living microbes in a 2-billion-year-old rock in South Africa, providing insights into early life on Earth and potentially aiding the search for life on Mars.

Researchers have discovered pockets of living microbes within a sealed fracture of a 2-billion-year-old rock from the Bushveld Igneous Complex in South Africa, an area known for its rich ore deposits. This is the oldest example of living microbes found within ancient rock to date.

To confirm that the microbes were indigenous to the ancient core sample and not caused by contamination during the retrieval and study process, the research team refined a technique they previously developed involving three types of imaging – infrared spectroscopy, electron microscopy, and fluorescent microscopy. These microbes could provide novel insights into the early evolution of life, and aid the search for extraterrestrial life in similarly aged rock samples brought back from Mars.

Researchers have developed a Martian atmospheric evolution model to propose a new theory about Mars’s past. Although Mars is currently a cold, dry planet, geological evidence suggests that liquid water existed there around 3 to 4 billion years ago. Where there is water, there is usually life. In their quest to answer the burning question about life on Mars, researchers at Tohoku University created a detailed model of organic matter production in the ancient Martian atmosphere.

Organic matter refers to the remains of living things such as plants and animals, or the byproduct of certain chemical reactions.

Whatever the case, the stable carbon isotope ratio (13C/12C) found in organic matter provides valuable clues about how these building blocks of life were originally formed, giving scientists a window into the past.

We often contemplate cyborgs, people enhanced by machines, but what would a civilization built upon cybernetics be like?

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