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Scientists Identify “Pioneer Peptide” That May Have Sparked Life on Earth

A team of Rutgers University scientists dedicated to pinpointing the primordial origins of metabolism – a set of core chemical reactions that first powered life on Earth – has identified part of a protein that could provide scientists clues to detecting planets on the verge of producing life.

The research, published on March 10 in the journal Science Advances.

<em>Science Advances</em> is a peer-reviewed, open-access scientific journal that is published by the American Association for the Advancement of Science (AAAS). It was launched in 2015 and covers a wide range of topics in the natural sciences, including biology, chemistry, earth and environmental sciences, materials science, and physics.

New mission to search for signs of alien life in Alpha Centauri

“Modern satellite technology will allow us to explore our celestial backyard.”

The University of Sydney and Bulgarian aerospace manufacturer EnduroSat have teamed up to search for alien life in our nearest star system, Alpha Centauri.

The plan for the TOLIMAN mission is to search for planets in the habitable zone around two Sun-like stars in the system, Alpha Centauri A and B, which are located four light-years from Earth.


ESA

The new mission was dubbed TOLIMAN after the star’s ancient Arabic name. It was backed by Breakthrough Initiatives, which is also responsible for a mission that aims to one day send a light sail probe to the star system.

The “Wow! Signal” is the most compelling evidence of alien life but it was only detected once

The Wow! signal is a radio signal detected by astronomer Jerry R. Ehman on August 15, 1977, while he was analyzing data from Ohio State University’s Big Ear radio telescope.

When the astronomer discovered the signal, he was so impressed with it that he wrote a comment “Wow!.” Thus, the mysterious signal came to be called the Wow! signal.

The signal appeared to come from the Sagittarius constellation, and it lasted for 72 seconds. The signal was unusual because it had a narrow bandwidth, was significantly stronger than background noise, and appeared to come from a fixed point in space.

A Trendy New Chemical Theory for Where the Aliens Are Hiding

There’s a theory that’s in vogue in astrochemistry called “Assembly Theory.” It posits that highly complex molecules—many acids, for example—could only come from living beings. The molecules are either part of living beings, or they’re things that intelligent living beings manufacture.

If Assembly Theory holds up, we could use it to search for aliens—by scanning distant planets and moons for complex molecules that should be evidence of living beings. That’s the latest idea from Assembly Theory’s originator, University of Glasgow chemist Leroy Cronin. “This is a radical new approach,” Cronin told The Daily Beast.

But not every expert agrees it would work—at least not anytime soon. To take chemical readings of faraway planets, scientists rely on spectroscopy. This is the process of interpreting a planet’s color palette to assess the possible mix of molecules in its atmosphere, land, and oceans.

Where did Earth’s water come from? Not melted meteorites, according to scientists

Water makes up 71% of Earth’s surface, but no one knows how or when such massive quantities of water arrived on Earth.

A new study published in the journal Nature brings scientists one step closer to answering that question. Led by University of Maryland Assistant Professor of Geology Megan Newcombe, researchers analyzed melted meteorites that had been floating around in space since the ’s formation 4 1/2 billion years ago. They found that these meteorites had extremely low content—in fact, they were among the driest extraterrestrial materials ever measured.

These results, which let researchers rule them out as the primary source of Earth’s water, could have important implications for the search for water—and life—on other planets. It also helps researchers understand the unlikely conditions that aligned to make Earth a habitable planet.

The multiverse: Our universe is suspiciously unlikely to exist—unless it is one of many, says physicist

It’s easy to envisage other universes, governed by slightly different laws of physics, in which no intelligent life, nor indeed any kind of organized complex systems, could arise. Should we therefore be surprised that a universe exists in which we were able to emerge?

That’s a question physicists including me have tried to answer for decades. But it is proving difficult. Although we can confidently trace cosmic history back to one second after the Big Bang, what happened before is harder to gauge. Our accelerators simply can’t produce enough energy to replicate the that prevailed in the first nanosecond.

But we expect that it’s in that first tiny fraction of a second that the key features of our universe were imprinted.

Fundamental constants: Is the universe fine-tuned for life?

Imagine a universe with extremely strong gravity. Stars would be able to form from very little material. They would be smaller than in our universe and live for a much shorter amount of time. But could life evolve there? It took human life billions of years to evolve on Earth under the pleasantly warm rays from the Sun after all.

Now imagine a with extremely weak gravity. Its matter would struggle to clump together to form stars, planets and—ultimately—living beings. It seems we are pretty lucky to have gravity that is just right for life in our universe.

This isn’t just the case for gravity. The values of many forces and in the universe, represented by some 30 so-called fundamental constants, all seem to line up perfectly to enable the evolution of intelligent life. But there’s no theory explaining what values the constants should have—we just have to measure them and plug their numbers into our equations to accurately describe the cosmos.

Is the universe fine-tuned for life?

For decades, various physicists have theorized that even the slightest changes in the fundamental laws of nature would make it impossible for life to exist. This idea, also known as the “fine-tuned universe” argument, suggests that the occurrence of life in the universe is very sensitive to the values of certain fundamental physics. Alter any of these values (as the logic goes), and life would not exist, meaning we must be very fortunate to be here.

But can this really be the case, or is it possible that life can emerge under different physical constants, and we just don’t know it? This question was recently tackled by Luke A. Barnes, a postdoctoral researcher at the Sidney Institute for Astronomy (SIA) in Australia. In his book, “A Fortunate Universe: Life in a Finely Tuned Cosmos,” he and Sydney astrophysics professor Geraint F. Lewis argued that a fine-tuned universe makes sense from a standpoint.

The authors also summarized these arguments in an invited contribution paper, which appeared in the Routledge Companion to Philosophy of Physics (1st ed.) In this paper, titled “The Fine-Tuning of the Universe for Life,” Barnes explains how “fine-tuning” consists of explaining observations by employing a “suspiciously precise assumption.” This, he argues, has been symptomatic of incomplete theories throughout history and is a common feature of modern cosmology and .

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