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Rogue Planets Could be Habitable

The search for potentially habitable planets is focused on exoplanets—planets orbiting other stars—for good reason. The only planet we know of with life is Earth and sunlight fuels life here. But some estimates say there are many more rogue planets roaming through space, not bound to or warmed by any star.

Could some of them support life?

The term ‘Rogue Planet’ is a colourful term used to describe what are actually interstellar objects (ISOs). But in the case of rogue planets, the ISOs are planetary-mass objects, rather than less massive objects like ‘Oumuamua or 2I/Borisov, the only two confirmed ISOs to enter our Solar System.

Rogue Planets have been somehow ejected from their solar systems. Young solar systems are chaotic places, where bodies collide with each other and where migrating gas giants can perturb smaller terrestrial planets from their orbits, sending them on an interstellar journey. It’s also possible that rogue planets form in interstellar space similar to how stars form. A planet could coalesce out of a cloud of gas and dust, along with a system of moons orbiting it. Sub-brown dwarfs are also considered rogue planets, but since they’re just gas, life is unlikely. In any case, rogue planets aren’t gravitationally bound to any star or stars. They’re free-floating.

We don’t know how many of them there are. If you ask Neil deGrasse Tyson there are billions of them in the Milky Way, maybe even trillions. Could any of them host life? Possibly.

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A star just 35 light-years away has been found to host a number of rocky exoplanets, and one that has a good chance of habitability.

Around the red dwarf L 98-59 orbit at least four planets, and the system looks to be fascinating. New observations confirm what prior research had already suggested – the existence of a terrestrial world with half the mass of Venus.

But the new observations also reveal new worlds in the same system, including an ocean planet, and what seems to be a super-Earth bang in the middle of the star's habitable zone.

"The planet in the habitable zone may have an atmosphere that could protect and support life," said astrophysicist María Rosa Zapatero Osorio of the Centre for Astrobiology in Spain.

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In 2018, scientists made a discovery that could change our understanding of the dusty, dry red ball that is Mars.

Radar signals bounced from just below the planet's surface revealed a shining patch, consistent with nothing so much as an underground pool of liquid water. Subsequent searches turned up even more shiny patches, suggesting a whole network of underground lakes.

Groundbreaking stuff, right? Although Mars has water in the form of ice, to date not a single drop of the liquid stuff has ever been found on our red buddy.

There's just one problem. According to a new analysis, which has found dozens more of these shiny patches, some of them are in regions that are just too cold for liquid water, even a brine, which can have a lower freezing temperature than freshwater.

"We're not certain whether these signals are liquid water or not, but they appear to be much more widespread than what the original paper found," said planetary scientist Jeffrey Plaut of NASA's Jet Propulsion Laboratory.

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On the broad Martian equatorial plain called Elysium Planitia, a huge swath of dark material has been hiding a secret, one that could upend our beliefs about the recent history of Mars.

In research published in April in Icarus a team led by David Horvath of the Planetary Science Institute used Mars Reconnaissance Orbiter (MRO) images to study rocky debris in the Cerberus Fossae fissures, finding evidence of volcanism on Mars — and what’s more, the Martian eruption happened so recently that ancient humans were already roaming the Earth.

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One of the great mysteries of modern space science is neatly summed up by the view from NASA's Perseverance, which just landed on Mars: Today it's a desert planet, and yet the rover is sitting right next to an ancient river delta.

The apparent contradiction has puzzled scientists for decades, especially because at the same time that Mars had flowing rivers, it was getting less than a third as much sunshine as we enjoy today on Earth.

But a new study led by University of Chicago planetary scientist Kite, an assistant professor of geophysical sciences and an expert on climates of other worlds, uses a computer model to put forth a promising explanation: Mars could have had a thin layer of icy, high-altitude clouds that caused a greenhouse effect.

"There's been an embarrassing disconnect between our evidence, and our ability to explain it in terms of physics and chemistry," said Kite. "This hypothesis goes a long way toward closing that gap."

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In recent years there has been an exhaustive study of red dwarf stars to find exoplanets in orbit around them. These stars have effective surface temperatures between 2400 and 3700 K (over 2000 degrees cooler than the Sun), and masses between 0.08 and 0.45 solar masses. In this context, a team of researchers led by Borja Toledo Padrón, a Severo Ochoa-La Caixa doctoral student at the Instituto de Astrofísica de Canarias (IAC), specializing in the search for planets around this type of stars, has discovered a super-Earth orbiting the star GJ 740, a red dwarf star situated some 36 light years from the Earth.

The planet orbits its star with a period of 2.4 days and its mass is around 3 times the mass of the Earth. Because the star is so close to the Sun, and the planet so close to the star, this new super-Earth could be the object of future researches with very large diameter telescopes towards the end of this decade. The results of the study were recently published in the journal Astronomy & Astrophysics.

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In fascinating new research, cosmologists explain the history of the universe as one of self-teaching, autodidactic algorithms.

The scientists, including physicists from Brown University and the Flatiron Institute, say the universe has probed all the possible physical laws before landing on the ones we observe around us today. Could this wild idea help inform scientific research to come?

In their novella-length paper, published to the pre-print server arXiV, the researchers—who received “computational, logistical, and other general support” from Microsoft—offer ideas “at the intersection of theoretical physics, computer science, and philosophy of science with a discussion from all three perspectives,” they write, teasing the bigness and multidisciplinary nature of the research.

Here’s how it works: Our universe observes a whole bunch of laws of physics, but the researchers say other possible laws of physics seem equally likely, given the way mathematics works in the universe. So if a group of candidate laws were equally likely, then how did we end up with the laws we really have?

“The notion of ‘learning’ as we use it is more than moment-to-moment, brute adaptation. It is a cumulative process that can be thought of as theorizing, modeling, and predicting. For instance, the DNA/RNA/protein system on Earth must have arisen from an adaptive process, and yet it foresees a space of organisms much larger than could be called upon in any given moment of adaptation.”

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Using the Atacama Large Millimeter/submillimeter Array (ALMA), in which the European Southern Observatory (ESO) is a partner, a team of astronomers has directly measured winds in Jupiter's middle atmosphere for the first time. By analyzing the aftermath of a comet collision from the 1990s, the researchers have revealed incredibly powerful winds, with speeds of up to 1450 kilometers an hour, near Jupiter's poles. They could represent what the team have described as a "unique meteorological beast in our solar system."

Jupiter is famous for its distinctive red and white bands, swirling clouds of moving gas that astronomers traditionally use to track winds in Jupiter's lower atmosphere. Astronomers have also seen, near Jupiter's poles, the vivid glows known as aurorae, which appear to be associated with strong winds in the planet's upper atmosphere. But until now, researchers had never been able to directly measure wind patterns in between these two atmospheric layers, in the stratosphere.

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