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Does Space Dust Transport Life Around The Galaxy

November 29, 2017 by  
Filed under Around The Net

It may not take an asteroid strike to transport life from one planet to another.

Fast-moving dust could theoretically knock microbes floating high up in a world’s atmosphere out into space, potentially sending the bugs on a trip to another planet — perhaps even one orbiting a different star, according to a new study.

“The proposition that space-dust collisions could propel organisms over enormous distances between planets raises some exciting prospects of how life and the atmospheres of planets originated,” study author Arjun Berera, a professor in the School of Physics and Astronomy at the University of Edinburgh in Scotland, said in a statement.  

“The streaming of fast space dust is found throughout planetary systems and could be a common factor in proliferating life,” Berera added.

Berera isn’t the first person to propose that organisms could hop from world to world throughout the cosmos. That basic idea, known as panspermia, has been around for thousands of years. It has received renewed interest recently, however, as scientists have demonstrated that some organisms — such as certain bacteria, and micro-animals known as tardigrades — can survive for extended periods in space.

But researchers have generally regarded comet or asteroid impacts as the only viable way to get simple life-forms off a planet and into space, whence they could perhaps blunder their way to a different habitable world. (We won’t consider here the “directed panspermia” idea, which posits that intelligent aliens have seeded the galaxy with life or its building blocks.)

Comet or asteroid impacts do indeed blast rocks from planet to planet. Scientists have found numerous meteorites here on Earth that were once part of Mars — including one known as ALH84001, which some scientists think may preserve signs of ancient Red Planet life.

In the new study, Berera examined what likely happens when bits of interplanetary dust hit molecules and particles in Earth’s atmosphere. This space stuff rains down on us every day, hitting the planet at speeds of between 22,400 mph and 157,000 mph (36,000 to 253,000 km/h).

He calculated that small particles floating at least 93 miles (150 kilometers) above Earth’s surface could theoretically get knocked into space by this wandering dust. It’s unclear if microbes could survive such violent collisions; that’s an area ripe for future research, Berera wrote in the new paper, which has been accepted for publication in the journal Astrobiology. (You can read the study for free at the online preprint site arXiv.org.)

And even if these micro-impacts are invariably fatal, they could still help life get a foothold on other worlds by sending its building blocks — the complex molecules that make up a microbe corpse, for example — out into space, he added.

Courtesy-Space

Astronomers Find New Alien Planet Suitable For Life

November 21, 2017 by  
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A newfound exoplanet may be one of the best bets to host alien life ever discovered — and it’s right in Earth’s backyard, cosmically speaking.

Astronomers have spotted a roughly Earth-mass world circling the small, dim star Ross 128, which lies just 11 light-years from the sun. The planet, known as Ross 128b, may have surface temperatures amenable to life as we know it, the researchers announced in a new study that will appear in the journal Astronomy & Astrophysics.

Ross 128b is 2.6 times more distant from Earth than Proxima b, the potentially habitable planet found in the nearest solar system to the sun. But Proxima b’s parent star, Proxima Centauri, blasts out a lot of powerful flares, potentially bathing that planet in enough radiation to stunt the emergence and evolution of life, scientists have said. [10 Exoplanets That Could Host Alien Life]

Radiation is likely much less of an issue for Ross 128b, because its parent star is not an active flarer, said discovery team leader Xavier Bonfils, of the Institute of Planetology and Astrophysics of Grenoble and the University of Grenoble Alpes in France.

“This is the closest Earth-mass planet potentially in the habitable zone that orbits a quiet star,” Bonfils told Space.com

Bonfils and his colleagues found Ross 128b using the High Accuracy Radial velocity Planet Searcher (HARPS), an instrument at the European Southern Observatory’s La Silla Observatory in Chile.

As its name suggests, HARPS employs the “radial velocity” method, noticing the wobbles in a star’s movement induced by the gravitational tugs of orbiting planets. (NASA’s prolific Kepler space telescope, by contrast, uses the “transit” technique, spotting tiny brightness dips caused when a planet crosses its host star’s face from the spacecraft’s perspective.)

The HARPS observations allowed Bonfils and his team to determine that Ross 128b has a minimum mass 1.35 times that of Earth, and that the planet orbits its host star once every 9.9 Earth days.

Such a tight orbit would render Ross 128b uninhabitable in our own solar system. But Ross 128 is much cooler than the sun, so the newfound world is likely temperate, the researchers said. Determining whether  the planet is actually capable of supporting life as we know it, however, would require a better understanding of its atmosphere, Bonfils said.

“Ross 128b receives 1.38 times [more] irradiation than Earth from our sun,” he said. “Some models made by theorists say that a wet Earth-size planet with such irradiation would form high-altitude clouds. Those clouds would reflect back to space a large fraction of the incident light, hence preventing too much greenhouse heating. With those clouds, the surface would remain cool enough to allow liquid water at the surface. Not all models agree, though, and others predict this new planet is rather like Venus.

Though both Ross 128 and Proxima Centauri are red dwarfs — the most common type of star in the Milky Way galaxy — they are very different objects.

“Proxima Centauri is particularly active, with frequent, powerful flares that may sterilize (if not strip out) its atmosphere,” Bonfils said. “Ross 128 is one of the quietest stars of our sample and, although it is a little further away from us (2.6x), it makes for an excellent alternative target.”

And the star may indeed be targeted in the not-too-distant-future — by giant ground-based instruments such as the European Extremely Large Telescope, the Giant Magellan Telescope and the Thirty Meter Telescope, all of which are scheduled to be up and running by the mid-2020s.

Such megascopes should be able to resolve Ross 128b and even search its atmosphere for oxygen, methane and other possible signs of life, Bonfils said. (NASA’s $8.9 billion James Webb Space Telescope, which is scheduled to launch in early 2019, probably won’t be able to perform such a biosignature search, the researchers said in their discovery paper. If Ross 128b transited its host star from Webb’s perspective, it would likely be a different story, they added.)

Earlier this year, by the way, radio astronomers detected a strange signal that seemed to be emanating from Ross 128. But further investigation revealed that the signal most likely came from an Earth-orbiting satellite, not an alien civilization.

Courtesy-Space

Astronomers Ponder The Role Of Physics In Life

September 25, 2017 by  
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Understanding the origin of life is arguably one of the most compelling quests for humanity. This quest has inevitably moved beyond the puzzle of life on Earth to whether there’s life elsewhere in the universe. Is life on Earth a fluke? Or is life as natural as the universal laws of physics?

Jeremy England, a biophysicist at the Massachusetts Institute of Technology, is trying to answer these profound questions. In 2013, he formulated a hypothesis that physics may spontaneously trigger chemicals to organize themselves in ways that seed “life-like” qualities.

Now, new research by England and a colleague suggests that physics may naturally produce self-replicating chemical reactions, one of the first steps toward creating life from inanimate substances.

This might be interpreted as life originating directly from the fundamental laws of nature, thereby removing luck from the equation. But that would be jumping the gun.

Life had to have come from something; there wasn’t always biology. Biology is born from the raw and lifeless chemical components that somehow organized themselves into prebiotic compounds, created the building blocks of life, formed basic microbes and then eventually evolved into the spectacular array of creatures that exist on our planet today.  

“Abiogenesis” is when something nonbiological turns into something biological and England thinks thermodynamics might provide the framework that drives life-like behavior in otherwise lifeless chemicals. However, this research doesn’t bridge life-like qualities of a physical system with the biological processes themselves, England said.

“I would not say I have done anything to investigate the ‘origin of life’ per se,” England told Live Science. “I think what’s interesting to me is the proof of principle – what are the physical requirements for the emergence of life-like behaviors?”

Self-organization in physical systems

When energy is applied to a system, the laws of physics dictate how that energy dissipates. If an external heat source is applied to that system, it will dissipate and reach thermal equilibrium with its surroundings, like a cooling cup of coffee left on a desk. Entropy, or the amount of disorder in the system, will increase as heat dissipates. But some physical systems may be  sufficiently out of equilibrium that they “self-organize” to make best use of an external energy source, triggering interesting self-sustaining chemical reactions that prevent the system from reaching thermodynamic equilibrium and thus maintaining an out-of-equilibrium state, England speculates. (It’s as if that cup of coffee spontaneously produces a chemical reaction that sustains a hotspot in the center of the fluid, preventing the coffee from cooling to an equilibrium state.) He calls this situation “dissipation-driven adaptation” and this mechanism is what drives life-like qualities in England’s otherwise lifeless physical system.

A key life-like behavior is self-replication, or (from a biological viewpoint) reproduction. This is the basis for all life: It starts simple, replicates, becomes more complex and replicates again. It just so happens that self-replication is also a very efficient way of dissipating heat and increasing entropy in that system.

In a study published July 18 in the journal Proceedings of the National Academy of Sciences,  England and co-author Jordan Horowitz tested their hypothesis. They carried out computer simulations on a closed system (or a system that doesn’t exchange heat or matter with its surroundings) containing a “soup” of 25 chemicals. Although their setup is very simple, a similar type of soup may have pooled on the surface of a primordial and lifeless Earth. If, say, these chemicals are concentrated and heated by an external source – a hydrothermal vent, for example – the pool of chemicals would need to dissipate that heat in accordance with the second law of thermodynamics. Heat must dissipate and the entropy of the system will inevitably increase.

Under certain initial conditions, he found that these chemicals may optimize the energy applied to the system by self-organizing and undergoing intense reactions to self-replicate. The chemicals fine-tuned themselves naturally. These reactions generate heat that obeys the second law of thermodynamics; entropy will always increase in the system and the chemicals would self-organize and exhibit the life-like behavior of self-replication.

“Essentially, the system tries a bunch of things on a small scale, and once one of them starts experiencing positive feedback, it does not take that long for it to take over the character of organization in the system,” England told Live Science.

This is a very simple model of what goes on in biology: chemical energy is burned in cells that are – by their nature – out of equilibrium, driving the metabolic processes that maintain life. But, as England admits, there’s a big difference between finding life-like qualities in a virtual chemical soup and life itself.

Sara Imari Walker, a theoretical physicist and astrobiologist at Arizona State University who was not involved in the current research, agrees.

“There’s a two-way bridge that needs to be crossed to try to bridge biology and physics; one is to understand how you get life-like qualities from simple physical systems and the other is to understand how physics can give rise to life,” Imari Walker told Live Science. “You need to do both to really understand what properties are unique to life and what properties are characteristic of things that you consider to be almost alive […] like a prebiotic system.”

Emergence of life beyond Earth?

Before we can even begin to answer the big question of whether these simple physical systems may influence the emergence of life elsewhere in the universe, it would be better to understand where these systems exist on Earth first.

“If, when you say ‘life,’ you mean stuff that is as stunningly impressive as a bacterium or anything else with polymerases and DNA, my work doesn’t yet tell us anything about how easy or difficult it is to make something that complex, so I shouldn’t speculate about what we’d be likely to find elsewhere than Earth,”  England said. (Polymerases are proteins that assemble DNA and RNA.)

This research doesn’t specifically identify how biology emerges from nonbiological systems, only that in some complex chemical situations, surprising self-organization occurs. These simulations do not consider other life-like qualities – such as adaptation to environment or reaction to stimuli. Also, this thermodynamics test on a closed system does not consider the role of information reproduction in life’s origins, said Michael Lässig, a statistical physicist and quantitative biologist at the University of Cologne in Germany.

“[This] work is indeed a fascinating result on non-equilibrium chemical networks but it is still a long way from a physics explanation of the origins of life, which requires the reproduction of information,” Lässig, who was not involved in the research, told Live Science.

There’s a critical role for information in living systems, added Imari Walker. Just because there appears to be natural self-organization exhibited by a soup of chemicals, it doesn’t necessarily mean living organization.

“I think there’s a lot of intermediate stages that we have to get through to go from simple ordering to having a full-on information processing architecture like a living cell, which requires something like memory and hereditary,” said Imari Walker. “We can clearly get order in physics and non-equilibrium systems, but that doesn’t necessarily make it life.”

To say England’s work could be the “smoking gun” for the origin of life is premature, and there are many other hypotheses as to how life may have emerged from nothing, experts said. But it is a fascinating insight into how physical systems may self-organize in nature. Now that researchers have a general idea about how this thermodynamic system behaves, it would be a nice next step to identify sufficiently out-of-equilibrium physical systems that naturally occur on Earth, England said.

Courtesy-Space

Astronomers Find Titanium Oxide On Aline Planet

September 22, 2017 by  
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For the first time ever, titanium oxide has been spotted in an exoplanet’s skies, a new study reports.

Astronomers using the European Southern Observatory’s Very Large Telescope (VLT) in Chile detected the substance in the atmosphere of WASP-19b, a huge, scorching-hot planet located 815 light-years from Earth.

The presence of titanium oxide in the atmosphere of WASP-19b can have substantial effects on the atmospheric temperature structure and circulation,” study co-author Ryan MacDonald, an astronomer at the University of Cambridge in England, said in a statement.  

One possible effect is “thermal inversion.” If enough titanium oxide is present, the stuff can keep heat from entering or exiting an atmosphere, causing upper layers to be hotter than lower layers, researchers said. (This phenomenon occurs in Earth’s stratosphere, but the culprit is ozone, not titanium oxide.)

Artist’s illustration showing the exoplanet WASP-19b, whose atmosphere contains titanium oxide. In large enough quantities, titanium oxide can prevent heat from entering or escaping an atmosphere, leading to a “thermal inversion” in which temperatures are higher in the upper atmosphere than lower down.

WASP-19b is a bizarre world about the mass of Jupiter. The alien planet lies incredibly close to its host star, completing one orbit every 19 hours. As a result, WASP-19b’s atmospheric temperatures are thought to hover around 3,600 degrees Fahrenheit (2,000 degrees Celsius).

The research team — led by Elyar Sedaghati of the European Southern Observatory, the German Aerospace Center and the Technical University of Berlin — studied WASP-19b for more than a year using the VLT’s refurbished FORS2 instrument. These observations allowed them to determine that small amounts of titanium oxide, along with water and wisps of sodium, swirl around in the exoplanet’s blistering air.

“Detecting such molecules is, however, no simple feat,” Sedaghati said in the same statement. “Not only do we need data of exceptional quality, but we also need to perform a sophisticated analysis. We used an algorithm that explores many millions of spectra spanning a wide range of chemical compositions, temperatures, and cloud or haze properties in order to draw our conclusions.”

In addition to shedding new light on WASP-19b, the new study — which was published online today (Sept. 13) in the journal Nature — should improve researchers’ modeling of exoplanet atmospheres in general, team members said.

“To be able to examine exoplanets at this level of detail is promising and very exciting,” said co-author Nikku Madhusudhan, also of the University of Cambridge. 

Courtesy-Space

Do Trappist-1 Planets Have Enough Water For Alien Life

September 11, 2017 by  
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The new study looks at how much ultraviolet (UV) radiation is received by each of the planets, because this could affect how much water the worlds could sustain over billions of years, according to the study. Lower-energy UV light can break apart water molecules into hydrogen and oxygen atoms on a planet’s surface, while higher-energy UV light (along with X-rays from the star) can heat a planet’s upper atmosphere and free the separated hydrogen and oxygen atoms into space, according to the study. (It’s also possible that the star’s radiation destroyed the planets’ atmospheres long ago.)

The researchers measured the amount of UV radiation bathing the TRAPPIST-1 planets using NASA’s Hubble Space Telescope, and in their paper they estimate just how much water each of the worlds could have lost in the 8 billion years since the system formed.

It’s possible that the six innermost planets (identified by the letters b, c, d, e, f and g), pelted with the highest levels of UV radiation, could have lost up to 20 Earth-oceans’ worth of water, according to the paper. But it’s also possible that the outermost four planets (e, f, g and h — the first three of which are in the star’s habitable zone) lost less than three Earth-oceans’ worth of water.

If the planets had little or no water to start with, the destruction of water molecules by UV radiation could spell the end of the planets’ habitability. But it’s possible that the planets were initially so rich in liquid water that, even with the water loss caused by UV radiation, they haven’t dried up,  according to one of the study’s authors, Michaël Gillon, an astronomer at the University of Liège in Belgium. Gillon was also lead author on two studies that first identified the seven TRAPPIST-1 planets.

“It is very likely that the planets formed much farther away from the star [than they are now] and migrated inwards during the first 10 million years of the system,” Gillon told Space.com in an email.

Farther away from their parent star, the planets might have formed in an environment rich in water ice, meaning the planets could have initially had very water-rich compositions.

“We’re talking about dozens, and maybe even hundreds of Earth-oceans, so a loss of 20 Earth-oceans wouldn’t matter much,” Gillon said. “What our results show is that even if the outer planets were initially quite water-poor like the original Earth, they could still have some water on their surfaces.”

Courtesy-Space

Astronomers Find Stratrosphere On Alien World

August 10, 2017 by  
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A huge, superhot alien planet has a stratrosphere, like Earth does, a new study suggests. 

“This result is exciting because it shows that a common trait of most of the atmospheres in our solar system — a warm stratosphere — also can be found in exoplanet atmospheres,” study co-author Mark Marley, of NASA’s Ames Research Center in California’s Silicon Valley, said in a statement.

“We can now compare processes in exoplanet atmospheres with the same processes that happen under different sets of conditions in our own solar system,” Marley added. [Gallery: The Strangest Alien Planets] 

The research team, led by Thomas Evans of the University of Exeter in England, detected spectral signatures of water molecules in the atmosphere of WASP-121b, a gas giant that lies about 880 light-years from Earth. These signatures indicate that the temperature of the upper layer of the planet’s atmosphere increases with the distance from the planet’s surface. In the bottom layer of the atmosphere, the troposphere, the temperature decreases with altitude, study team members said.

WASP-121b lies incredibly close to its host star, completing one orbit every 1.3 days. The planet is a “hot Jupiter”; temperatures at the top of its atmosphere reach a sizzling 4,500 degrees Fahrenheit (2,500 degrees Celsius), researchers said.

“The question [of] whether stratospheres do or do not form in hot Jupiters has been one of the major outstanding questions in exoplanet research since at least the early 2000s,” Evans told Space.com. “Currently, our understanding of exoplanet atmospheres is pretty basic and limited. Every new piece of information that we are able to get represents a significant step forward.”

The discovery is also significant because it shows that atmospheres of distant exoplanets can be analyzed in detail, said Kevin Heng of the University of Bern in Switzerland, who is not a member of the study team. 

“This is an important technical milestone on the road to a final goal that we all agree on, and the goal is that, in the future, we can apply the very same techniques to study atmospheres of Earth-like exoplanets,” Heng told Space.com. “We would like to measure transits of Earth-like planets. We would like to figure out what type of molecules are in the atmospheres, and after we do that, we would like to take the final very big step, which is to see whether these molecular signatures could indicate the presence of life.”

Available technology does not yet allow such work with small, rocky exoplanets, researchers said. 

“We are focusing on these big gas giants that are heated to very high temperatures due to the close proximity of their stars simply because they are the easiest to study with the current technology,” Evans said. “We are just trying to understand as much about their fundamental properties as possible and refine our knowledge, and, hopefully in the decades to come, we can start pushing towards smaller and cooler planets.”

WASP-121b is nearly twice the size of Jupiter. The exoplanet transits, or crosses the face of, its host star from Earth’s perspective. Evans and his team were able to observe those transits using an infrared spectrograph aboard NASA’s Hubble Space Telescope.

“By looking at the difference in the brightness of the system for when the planet was not behind the star and when it was behind the star, we were able to work out the brightness and the spectrum of the planet itself,” Evans said. “We measured the spectrum of the planet using this method at a wavelength range which is very sensitive to the spectral signature of water molecules.”

The team observed signatures of glowing water molecules, which indicated that WASP-121b’s atmospheric temperatures increase with altitude, Evans said. If the temperature decreased with altitude, infrared radiation would at some point pass through a region of cooler water-gas, which would absorb the part of the spectrum responsible for the glowing effect, he explained. 

There have been hints of stratospheres detected on other hot Jupiters, but the new results are the most convincing such evidence to date, Evans said.

“It’s the first time that it has been done clearly for an exoplanet atmosphere, and that’s why it’s the strongest evidence to date for an exoplanet stratosphere,” he said. 

He added that researchers might be able to move closer to studying more Earth-like planets with the arrival of next-generation observatories such as NASA’s James Webb Space Telescope and big ground-based observatories such as the Giant Magellan Telescope (GMT), the European Extremely Large Telescope (E-ELT) and the Thirty Meter Telescope (TMT). JWST is scheduled to launch late next year, and GMT, E-ELT and TMT are expected to come online in the early to mid-2020s.

Courtesy-Space

NASA Finds More Alien Worlds

June 28, 2017 by  
Filed under Around The Net

NASA announced the latest crop of planet discoveries from the Kepler Space Telescope during a briefing on Monday morning June 19. 

The briefing will be at 11 a.m. EDT (1500 GMT) during the Kepler Science Conference at NASA’s Ames Research Center in California. You can watch the exoplanet announcement here, courtesy of NASA TV. NASA will livestream the conference.

The briefing will incude a panel of four experts, according to a statement by NASA: Mario Perez, Kepler program scientist in the Astrophysics Division of NASA’s Science Mission Directorate in Washington; Susan Thompson, Kepler research scientist at the SETI Institute in Mountain View, California; Benjamin Fulton, doctoral candidate at the University of Hawaii at Manoa and the California Institute of Technology; and Courtney Dressing, NASA Sagan Fellow at the California Institute of Technology. A question-and-answer session will follow.

Kepler has been hunting for extrasolar planets since its launch in 2009. This latest set of exoplanet candidates will use a more complete data set than ever before, with analysis of greater sophistication. The spacecraft started a new mission, called K2, after the failure of two reaction wheels that stabilized the spacecraft in 2013. The K2 mission was a modified version of the original planet-hunting mandate, seeking worlds around relatively nearby red dwarf stars. 

Newfound exoplanets are often listed as candidates because it can take time to verify that they are actually there. Kepler finds planets by observing the light of stars over a period of time, using a process called the transit method. If the light dims, then it’s possible a planet passed in front of it. The evidence for an exoplanet is considered stronger if the light dims more than once on a predictable schedule, indicating that something is in orbit around the star. 

Kepler was the first mission capable of seeing planets the size of Earth around other stars in the “habitable zone” — the region at a distance from a star where liquid water could exist without freezing or boiling away immediately. 

According to NASA, thus far Kepler has found 4,496 exoplanet candidates. Some 2,335 have been confirmed and 21 are Earth-size planets in the habitable zone. Since the mission was renamed K2, an additional 520 exoplanet candidates have been found, with 148 confirmed.

 

Courtesy-Space

Can Tiny Interstellar Probes Test The Panspermia Theory

June 9, 2017 by  
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Some of the first spacecraft that humanity sends to other solar systems may carry microscopic ambassadors from Earth.

The $100 million Breakthrough Starshot initiative is working to develop the technology required to accelerate tiny, sail-equipped probes to 20 percent the speed of light, using powerful lasers. 

If everything goes well, large fleets of these 1-gram spacecraft could begin launching toward Proxima b and other nearby alien worlds within 20 years or so, project representatives have said. The probes would characterize these planets in detail and search for signs of life, but some could perform other work as well.

For example, Breakthrough Starshot adviser Jeff Kuhn, a physicist at the University of Hawaii, said that the project offers a great opportunity to investigate the feasibility of interstellar panspermia — the idea that life might have spread from place to place throughout the Milky Way galaxy, and perhaps even the larger universe.

During a panel discussion on April 21 at the Breakthrough Discuss conference in Stanford, California, Kuhn noted that spores of the bacteria species Bacillus subtilis can survive for at least six years when exposed to the space environment. 

“I think it would be fun, on one of these disposable chips, to put a little colony of Bacillus, send it for 20 years, turn it on, give it some nutrients and see if it’s still alive, just to experimentally decide whether or not panspermia works over interstellar distances,” Kuhn said.

That comment elicited a response from audience member Philip Lubin, a physics professor at the University of California, Santa Barbara, who’s a key player in the development of Breakthrough Starshot’s laser-propulsion system.

“A part of our program — at least on the NASA side, because we haven’t cleared this with Breakthrough yet — is actually to put organisms to sleep, in stasis mode,” Lubin said at the conference. (Lubin and his group are also developing projects with the aid of NASA grant money.)

“And there are certain organisms known as C. elegans, which we’re going to embed human DNA into and send them out and then awaken them on arrival,” Lubin added, referring to a tiny roundworm species that’s a common study animal for biologists. “However, I expect that will be a highly controversial thing to do.”

The panspermia hypothesis posits that Earth life might have arrived, rather than originated, here.

This idea is not as fringe as you may think. For example, some scientists argue that, in the ancient past, the Martian environment was more conducive to life’s emergence than that of Earth. 

And it’s not terribly uncommon for the two planets to exchange material, in the form of rocks and dirt blasted into space by asteroid strikes. Orbital dynamics dictates that it’s much easier for Martian stuff to reach Earth than the other way around, so we may all be Martians, according to this line of thinking.

It may even be possible for life-forms to move from one star system to another, some panspermia adherents say. For example, hardy microscopic spores could be transported vast distances by stellar radiation pressure. Or frigid bodies orbiting far from their parent stars could come under the gravitational sway of a neighboring sun. [5 Bold Claims of Alien Life]

“We know that there are interstellar carriers: The Oort Cloud easily transfers from one solar system to another,” Kuhn said. (The Oort Cloud is our own solar system’s huge comet repository, which is believed to begin about 0.8 light-years from the sun.)

But there are a number of factors that could make it difficult for life to move through space. 

For example, putative Martian microbes ejected by an asteroid or comet strike would have to survive the intense heat and pressure of the impact, the harsh temperatures and high radiation levels of deep space and the rigors of atmospheric entry to have any hope of colonizing Earth. (The B. subtilis in the long-term experiment cited by Kuhn were in low Earth orbit, which has a more benign radiation environment thanks to our planet’s magnetic field.) 

Then, there’s the issue of time, which makes interstellar panspermia unlikely, according to Harvard University astronomy professor Dimitar Sasselov.

“With the short-lived universe we live in, the more likely scenario is that most of the planets that we’ll see life on are also the locations where it emerged from the planetary conditions,” Sasselov, who’s also the founding director of the Harvard Origins of Life Initiative, said during a different panel discussion at Breakthrough Discuss on April 20.

The transfer of organisms between nearby planets in the same solar system is feasible, he added. But interstellar panspermia “just takes too long, and it’s too far of a journey, and the probabilities currently, in the current universe, are just too small,” Sasselov said.

All of the above speculation assumes naturally occurring “accidental” panspermia. But it’s also possible that intelligent aliens could set panspermia in motion, either unintentionally (via contaminated spacecraft) or intentionally (in an effort to seed other worlds), some scientists have said.

Breakthrough Starshot, and projects like it, could give humanity this ability as well.

“We can be the panspermia which actually seeds other planets if we want,” Lubin said. “And it’s something to think about for the future.”

Now that would be controversial.

Courtesy-Space

Does Trappist-1 Planets Have Moons

June 5, 2017 by  
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While we know of thousands of exoplanets and exoplanet candidates, the search for moons outside of our solar system is just beginning. We don’t have a confirmed exomoon discovery yet, but they’re bound to be out there.

Finding exomoons will help us better understand habitability on Earth. Some experts say a reason that life arose is our own moon is so close to the size of our planet, which stabilized its axis rotation. However, other studies (such as this 2011 American Astronomical Society paper quoted in a NASA Astrobiology story) argue that the gravitational influence of other planets in our solar system provide enough stability.

A new study looks at the possibilities of large moons in TRAPPIST-1, a notoriously crowded exoplanet system that may have habitable planets within it. Earlier this year, observations from NASA’s Spitzer Space Telescope indicated that seven planets here could be rocky and have liquid water on their surfaces, making TRAPPIST-1 the system with the most potentially habitable planets.

But even before NASA’s discovery, TRAPPIST-1 was known and pondered by scientists, including the author of the new paper, Stephen Kane, an associate professor of astronomy at San Francisco State University who specializes in exoplanets.

“I have several publications now on exomoons, and for many years I’ve been thinking about how the ability of a planet to host a moon scales with the presence of nearby planets and proximity to the host star,” Kane said in an e-mail. “The discovery of the TRAPPIST-1 system prompted me to finally calculate whether or not planets in compact planetary systems can actually harbor moons.”

Kane cautioned that scientists can’t overly attribute Earth’s habitability to our moon, because Earth is the only known habitable planet. However, the moon does have an important role: It creates significant tides on Earth, which probably helped create the tidal pools in which early biochemistry could occur.

“The presence of the moon has helped to stabilize changes in the tilt of the Earth’s rotational axis, which in turn creates longer periods of climate stability,” Kane added. “So although it’s difficult to say what the Earth would be like without a moon, we can certainly describe ways in which it has positively influenced our present environment.”

For TRAPPIST-1, Kane found that the planets are so tightly packed together that large moons would likely be impossible. While the rotational axes of the planets would quickly change and have more chaotic climates, he said, life could still evolve — it just might take a longer time.

Kane’s methodology involved studying the influences of two parameters: the Hill radius, or the area in space in which a planet exerts gravitational influence based on its mass and distance from the host star, and the Roche limit, which identifies where the gravitational effect near a planet is too strong for a moon to survive.

“A moon can only exist around a planet if it lies between these two boundaries: too close and it will be destroyed, too far away and it will escape the gravitational influence of the planet,” Kane said. “The results of the study described in my paper show that, for most planets in compact planetary systems, the Hill radius and Roche limit are close enough to each other that there is no space in which a moon can exist and so such planets cannot have moons in orbit around them.”

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Do Any Trappist 1 Planets Have Moons

May 19, 2017 by  
Filed under Around The Net

While we know of thousands of exoplanets and exoplanet candidates, the search for moons outside of our solar system is just beginning. We don’t have a confirmed exomoon discovery yet, but they’re bound to be out there.

Finding exomoons will help us better understand habitability on Earth. Some experts say a reason that life arose is our own moon is so close to the size of our planet, which stabilized its axis rotation. However, other studies (such as this 2011 American Astronomical Society paper quoted in a NASA Astrobiology story) argue that the gravitational influence of other planets in our solar system provide enough stability.

A new study looks at the possibilities of large moons in TRAPPIST-1, a notoriously crowded exoplanet system that may have habitable planets within it. Earlier this year, observations from NASA’s Spitzer Space Telescope indicated that seven planets here could be rocky and have liquid water on their surfaces, making TRAPPIST-1 the system with the most potentially habitable planets.

But even before NASA’s discovery, TRAPPIST-1 was known and pondered by scientists, including the author of the new paper, Stephen Kane, an associate professor of astronomy at San Francisco State University who specializes in exoplanets.

“I have several publications now on exomoons, and for many years I’ve been thinking about how the ability of a planet to host a moon scales with the presence of nearby planets and proximity to the host star,” Kane said in an e-mail. “The discovery of the TRAPPIST-1 system prompted me to finally calculate whether or not planets in compact planetary systems can actually harbor moons.”

Kane cautioned that scientists can’t overly attribute Earth’s habitability to our moon, because Earth is the only known habitable planet. However, the moon does have an important role: It creates significant tides on Earth, which probably helped create the tidal pools in which early biochemistry could occur.

“The presence of the moon has helped to stabilize changes in the tilt of the Earth’s rotational axis, which in turn creates longer periods of climate stability,” Kane added. “So although it’s difficult to say what the Earth would be like without a moon, we can certainly describe ways in which it has positively influenced our present environment.”

For TRAPPIST-1, Kane found that the planets are so tightly packed together that large moons would likely be impossible. While the rotational axes of the planets would quickly change and have more chaotic climates, he said, life could still evolve — it just might take a longer time.

Kane’s methodology involved studying the influences of two parameters: the Hill radius, or the area in space in which a planet exerts gravitational influence based on its mass and distance from the host star, and the Roche limit, which identifies where the gravitational effect near a planet is too strong for a moon to survive.

“A moon can only exist around a planet if it lies between these two boundaries: too close and it will be destroyed, too far away and it will escape the gravitational influence of the planet,” Kane said. “The results of the study described in my paper show that, for most planets in compact planetary systems, the Hill radius and Roche limit are close enough to each other that there is no space in which a moon can exist and so such planets cannot have moons in orbit around them.”

Courtesy-Space

Is Ridley Scott Right About An Alien Encounter

May 16, 2017 by  
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Film director Ridley Scott, who delights in terrifying moviegoers with his cinematic blend of horror and science fiction, suggested in a recent interview that the scary prospect of belligerent invading aliens might transcend the realm of sci-fi. According to Scott, hundreds of alien species are “out there” on distant worlds, and Earth’s inhabitants should prepare for the worst if they ever decide to visit our planet.

One scientist, though, says that Scott’s information about such hostile, and abundant, aliens is off-base and unsupported.

Scott told Agence France-Presse (AFP) about his belief in “superior beings,” while fielding questions about his latest movie, “Alien: Covenant,” opening in theaters in the U.S. on May 19. He warned that any extraterrestrial travelers who are technologically advanced enough to show up on our doorstep would likely be very intelligent and very hostile. And unlike the scenarios that dominate movies — if we go toe-to-toe with these invaders, we probably won’t be the victors, he said.

“If you are stupid enough to challenge them you will be taken out in three seconds,” Scott told AFP. [Greetings, Earthlings! 8 Ways Aliens Could Contact Us]

In the interview, Scott explained that “the experts” estimate there are “between 100 and 200 entities” on other planets, following what could be a similar evolutionary path to ours. And if they get here first, our best bet would be to “run for it,” AFP reported.

The possibility of intelligent, technologically adept alien life has intrigued science-fiction writers and readers since the French writer Voltaire published his short story “Micromégas” in 1752, describing two extraterrestrial visitors to Earth — one from the planet Saturn and one from a planet orbiting the star Sirius.

Scott has made his own contributions to the genre, most notably with his string of “Alien” movies, which imagine a highly adaptable and morphologically flexible alien species. The so-called xenomorphs breed quickly and are ruthlessly efficient at overpowering humans, either swiftly dismembering them or cultivating them as hosts for their young — luckily, in isolated locations that are far from our home planet.

But though Scott is a skilled sci-fi yarn-spinner, his assessment of real-world alien threats could use a script doctor, according to Seth Shostak, senior astronomer with the SETI Institute, a research institution dedicated to the search for communication signals produced by intelligent extraterrestrial life.

To begin with, Scott’s “expert” estimate of 100 to 200 “entities” is entirely unsubstantiated, Shostak told Live Science.

“We have absolutely no data that would tell you what that number might be,” he said.

In fact, estimates based on data about known planets and galaxies suggest that the actual number of intelligent extraterrestrial life forms could, in fact, be significantly higher. With approximately 1 trillion planets in our galaxy alone, and about 2 trillion more galaxies, that adds up to…well, it’s a lot of planets, Shostak said.

To narrow the search a bit, scientists could start by just looking at the trillion planets in our own galaxy, he said. Only a fraction of those planets might be capable of supporting life — perhaps 1 in 10. And maybe only 1 in 1,000 could produce and support life more complex than bacteria, he said.

That gives us about a billion planets in our galaxy that might harbor some type of intelligent life. But over time, life on many of those planets could have already waxed and waned — self-destructed or been wiped out. Perhaps only one planet in a million of those intelligent-life-harboring worlds still support life capable of contacting humans. That adds up to about 1,000 planets that could potentially hold intelligent, extraterrestrial species, Shostak told Live Science.

However, if a planet is more than 70 light-years from Earth, it hasn’t yet received any radio signals from us. Its residents, no matter how technologically adept, wouldn’t know humans exist yet. Even if long-distance observations of Earth told them we had oxygen in our atmosphere — and thereby some form of life — they’d be very unlikely to travel all this way to look at what might amount to just a lot of bacteria, Shostak added. 

Neither would extraterrestrials be likely to invade our solar system merely to steal our resources, he said. If a civilization is advanced enough that they’ve exhausted all the resources of their entire star system — every planet, moon and asteroid — and are all out of natural materials, they’re probably at a stage where they could create what they needed from simpler materials in their own backyard, rather than traveling across the galaxy for a very limited supply, Shostak said.

It’s equally unlikely they’d be showing up because they thought humans would make an excellent addition to their diet, he said.

“To do that, they would have to know that we had something interesting within our bodies that they could metabolize, and their body chemistry would probably be very different from ours,” Shostak said.

But Scott did get one thing right: If extraterrestrials are capable of building spacecraft that can transport them to our planet, they certainly would be technologically “superior” to people, Shostak said. And if he saw a spaceship suddenly appear, Shostak admitted that he’d probably do as Scott suggested — and just “run for it.”

Courtesy-Space

Is Oxygen Needed To Support Alien Life?

May 4, 2017 by  
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The hot springs of Yellowstone National Park may be extreme environments, but they are host to a diversity of microbes that could shed light on the evolution of life on Earth and, perhaps, what lurks on distant planets. 

While photosynthetic life cannot tolerate the high temperatures of hot springs, microorganisms that are chemosynthetic — meaning they rely solely on chemicals, rather than sunshine, as their energy source — do well there. Many of these peculiar microbes are believed to be the closest modern relatives to the earliest life on our planet. 

“Chemosynthetic microorganisms provide useful models for understanding how life might persist in extraterrestrial systems, like the subsurface of Europa, for instance, where light energy will not be available but abundant sources of chemical energy might be,” said Daniel Colman, a geomicrobiologist at Montana State University in Bozeman.

In 2014, Colman and his colleagues collected samples from chemosynthetic microbial communities in 15 hot springs in Yellowstone National Park. Hot springs are complex environments, where nutrient availability varies widely, even within the same hot spring. Colman analyzed how these variations might shape the kinds of chemosynthetic communities that might exist at any given spot. 

Colman and his team detailed their findings in the paper “Ecological differentiation in planktonic and sediment-associated chemotrophic microbial populations in Yellowstone hot springs” in the journal FEMS Microbiology Ecology.

The researchers looked at microorganisms that were either planktonic, that is, free-swimming, or those living in sediment, and then examined the chemistry of the water and the mineralogy of the sediments.

They focused on substances known as oxidants, which help organisms capture energy by stripping electrons from nutrients. Whereas humans and many other organisms rely on oxygen to act as their primary oxidant, chemosynthetic microbes rely on other oxidants that provide less energy, such as forms of iron and sulfur that are oxidized (oxidized materials have lost electrons).

The scientists found that planktonic communities in Yellowstone were dominated by bacteria that are microaerophiles, which need oxygen to survive but at concentrations lower than is present in Earth’s atmosphere. In contrast, sediment communities in Yellowstone were dominated by chemosynthetic microbes that rely on inorganic substances such as elemental sulfur or oxidized iron as their oxidants. 

These findings shed light on how and why hot spring microbes in sediments differ from those in the water. Microbes living in water that has been exposed to, and mixed with air, can use oxygen from the air as their oxidant, while microbes in sediments that are likely oxygen-poor have to make do with other kinds of oxidants. The researchers expect that early life on Earth was limited by the availability of oxidants and had to make do with what was around them. The same might be true of life elsewhere in the Universe.

“Understanding the present-day distributions of microorganisms as they relate to environmental factors can provide an idea of how life evolved in response to changing environments over Earth’s history and over the history of life’s evolution,” Colman said. 

Colman is especially interested in the subsurface microbial communities at Yellowstone, since they may, in some ways, resemble extraterrestrial settings on places like Europa. Nothing is known of the nature, or even existence of, a shallow, high-temperature subsurface biosphere in Yellowstone National Park, since drilling of any kind is prohibited on national park lands. 

NASA is interested in this research because developing an understanding of life in the hot springs of Yellowstone has the potential to shed light on how life may thrive in extraterrestrial environments that are similarly high in temperature and pressure and low in nutrients, Colman said. “These environments are understudied in astrobiology research, but hold tremendous promise as accessible analogs for extraterrestrial habitable environments that might be present on Enceladus, Mars, or Europa,” Colman said.

For instance, just as the sediments of Yellowstone’s hot springs are low in oxygen, “we would expect that life in other planetary body subsurface environments would likely be plagued by a chronic lack of oxidants, like oxygen, and would need to make do with oxidants that provide less energy,” Colman said.

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Is Silicon Based Life Possible?

April 26, 2017 by  
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Science fiction has long imagined alien worlds inhabited by silicon-based life, such as the rock-eating Horta from the original Star Trek series. Now, scientists have for the first time shown that nature can evolve to incorporate silicon into carbon-based molecules, the building blocks of life on Earth.

As for the implications these findings might have for alien chemistry on distant worlds, “my feeling is that if a human being can coax life to build bonds between silicon and carbon, nature can do it too,” said the study’s senior author Frances Arnold, a chemical engineer at the California Institute of Technology in Pasadena. The scientists detailed their findings recently in the journal Science.

Carbon is the backbone of every known biological molecule. Life on Earth is based on carbon, likely because each carbon atom can form bonds with up to four other atoms simultaneously. This quality makes carbon well-suited to form the long chains of molecules that serve as the basis for life as we know it, such as proteins and DNA.  

Still, researchers have long speculated that alien life could have a completely different chemical basis than life on Earth. For example, instead of relying on water as the solvent in which biological molecules operate, perhaps aliens might depend on ammonia or methane. And instead of relying on carbon to create the molecules of life, perhaps aliens could use silicon.

Carbon and silicon are chemically very similar in that silicon atoms can also each form bonds with up to four other atoms simultaneously. Moreover, silicon is one of the most common elements in the universe. For example, silicon makes up almost 30 percent of the mass of the Earth’s crust, and is roughly 150 times more abundant than carbon in the Earth’s crust. 

Scientists have long known that life on Earth is capable of chemically manipulating silicon. For instance, microscopic particles of silicon dioxide called phytoliths can be found in grasses and other plants, and photosynthetic algae known as diatoms incorporate silicon dioxide into their skeletons. However, there are no known natural instances of life on Earth combining silicon and carbon together into molecules.

Still, chemists have artificially synthesized molecules comprised of both silicon and carbon. These organo-silicon compounds are found in a wide range of products, including pharmaceuticals, sealants, caulks, adhesives, paints, herbicides, fungicides, and computer and television screens. Now, scientists have discovered a way to coax biology to chemically bond carbon and silicon together. 

“We wanted to see if we could use what biology already does to expand into whole new areas of chemistry that nature has not yet explored,” Arnold said. [Facts About Silicon]

The researchers steered microbes into creating molecules never before seen in nature through a strategy known as ‘directed evolution,’ which Arnold pioneered in the early 1990s. Just as farmers have long modified crops and livestock by breeding generations of organisms for the traits they want to appear, so too have scientists bred microbes to create the molecules they desire. Scientists have used directed evolutionary strategies for years to create household goods such as detergents, and to develop environmentally-friendly ways to make pharmaceuticals, fuels and other industrial products. (Conventional chemical manufacturing processes can require toxic chemicals; in contrast, directed evolutionary strategies use living organisms to create molecules and generally avoid chemistry that would prove harmful to life.)

Arnold and her team — synthetic organic chemist Jennifer Kan, bioengineer Russell Lewis, and chemist Kai Chen — focused on enzymes, the proteins that catalyze or accelerate chemical reactions. Their aim was to create enzymes that could generate organo-silicon compounds. 

“My laboratory uses evolution to design new enzymes,” Arnold said. “No one really knows how to design them — they are tremendously complicated.  But we are learning how to use evolution to make new ones, just as nature does.”

First, the researchers started with enzymes they suspected could, in principle, chemically manipulate silicon. Next, they mutated the DNA blueprints of these proteins in more or less random ways and tested the resulting enzymes for the desired trait. The enzymes that performed best were mutated again, and the process was repeated until the scientists reached the results they wanted.

Arnold and her colleagues started with enzymes known as heme proteins, which all have iron at their hearts and are capable of catalyzing a wide variety of reactions. The most widely recognized heme protein is likely hemoglobin, the red pigment that helps blood carry oxygen. 

After testing a variety of heme proteins, the scientists concentrated on one from Rhodothermus marinus, a bacterium from hot springs in Iceland. The heme protein in question, known as cytochrome c, normally shuttles electrons to other proteins in the microbe, but Arnold and her colleagues found that it could also generate low levels of organo-silicon compounds. 

After analyzing cytochrome c’s structure, the researchers suspected that only a few mutations might greatly enhance the enzyme’s catalytic activity. Indeed, only three rounds of mutations were enough to turn this protein into a catalyst that could generate carbon-silicon bonds more than 15 times more efficiently than the best synthetic techniques currently available. The mutant enzyme could generate at least 20 different organo-silicon compounds, 19 of which were new to science, Arnold said. It remains unknown what applications people might be able to find for these new compounds.

“The biggest surprise from this work is how easy it was to get new functions out of biology, new functions perhaps never selected for in the natural world that are still useful to human beings,” Arnold said. “The biological world always seems poised to innovate.”

In addition to showing that the mutant enzyme could self-generate organo-silicon compounds in a test tube, the scientists also showed that E. coli bacteria, genetically engineered to produce the mutant enzyme within themselves, could also create organo-silicon compounds. This result raises the possibility that microbes somewhere could have naturally evolved the ability to create these molecules.

“In the universe of possibilities that exist for life, we’ve shown that it is a very easy possibility for life as we know it to include silicon in organic molecules,” Arnold said. “And once you can do it somewhere in the universe, it’s probably being done.” 

It remains an open question why life on Earth is based on carbon when silicon is more prevalent in Earth’s crust. Previous research suggests that compared to carbon, silicon can form chemical bonds with fewer kinds of atoms, and it often forms less complex kinds of molecular structures with the atoms that it can interact with. By giving life the ability to create organo-silicon compounds, future research can test why life here or elsewhere may or may not have evolved to incorporate silicon into biological molecules.

In addition to the astrobiology implications, the researchers noted that their work suggests biological processes could generate organo-silicon compounds in ways that are more environmentally friendly and potentially much less expensive than existing methods of synthesizing these molecules. For example, current techniques for creating organo-silicon compounds often require precious metals and toxic solvents.

The mutant enzyme also makes fewer unwanted byproducts. In contrast, existing techniques typically require extra steps to remove undesirable byproducts, adding to the cost of making these molecules.

“I’m talking to several chemical companies right now about potential applications for our work,” Arnold said. “These compounds are hard to make synthetically, so a clean biological route to produce these compounds is very attractive.”

Future research can explore what advantages and disadvantages the ability to create organo-silicon compounds might have for organisms. “By giving this capability to an organism, we might see if there is, or is not, a reason why we don’t stumble across it in the natural world,” Arnold said.

The research was funded by the National Science Foundation, the Caltech Innovation Initiative program, and the Jacobs Institute for Molecular Engineering for Medicine at Caltech.

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Is A Mysterious Cosmic Light Powering Alien Spaceships?

March 22, 2017 by  
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Bizarre flashes of cosmic light may actually be generated by advanced alien civilizations, as a way to accelerate interstellar spacecraft to tremendous speeds, a new study suggests.

Astronomers have catalogued just 20 or so of these brief, superbright flashes, which are known as fast radio bursts (FRBs), since the first one was detected in 2007. FRBs seem to be coming from galaxies billions of light-years away, but what’s causing them remains a mystery.

“Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven’t identified a possible natural source with any confidence,” study co-author Avi Loeb, a theorist at the Harvard-Smithsonian Center for Astrophysics, said in a statement Thursday (March 9). “An artificial origin is worth contemplating and checking.”  ]

One potential artificial origin, according to the new study, might be a gigantic radio transmitter built by intelligent aliens. So Loeb and lead author Manasvi Lingam, of Harvard University, investigated the feasibility of this possible explanation.

And the huge amounts of energy involved wouldn’t necessarily melt the structure, as long as it was water-cooled. So, Lingam and Loeb determined, such a gigantic transmitter is technologically feasible (though beyond humanity’s current capabilities).

Why would aliens build such a structure? The most plausible explanation, according to the study team, is to blast interstellar spacecraft to incredible speeds. These craft would be equipped with light sails, which harness the momentum imparted by photons, much as regular ships’ sails harness the wind. (Humanity has demonstrated light sails in space, and the technology is the backbone of Breakthrough Starshot, a project that aims to send tiny robotic probes to nearby star systems.) 

Indeed, a transmitter capable of generating FRB-like signals could drive an interstellar spacecraft weighing 1 million tons or so, Lingam and Loeb calculated.

“That’s big enough to carry living passengers across interstellar or even intergalactic distances,” Lingam said in the same statement.

Humanity would catch only fleeting glimpses of the “leakage” from these powerful beams (which would be trained on the spacecraft’s sail at all times), because the light source would be moving constantly with respect to Earth, the researchers pointed out.

The duo took things a bit further. Assuming that ET is responsible for most FRBs, and taking into account the estimated number of potentially habitable planets in the Milky Way (about 10 billion), Lingam and Loeb calculated an upper limit for the number of advanced alien civilizations in a galaxy like our own: 10,000.

Lingam and Loeb acknowledge the speculative nature of the study. They aren’t claiming that FRBs are indeed caused byaliens; rather, they’re saying that this hypothesis is worthy of consideration.

“Science isn’t a matter of belief; it’s a matter of evidence,” Loeb said. “Deciding what’s likely ahead of time limits the possibilities. It’s worth putting ideas out there and letting the data be the judge.”

The new study has been accepted for publication in The Astrophysical Journal Letters. You can read it for free on the online preprint site arXiv.org.

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Kepler Beams Raw Data From TRAPPIST-1

March 21, 2017 by  
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Scientists, have at it: NASA has released raw data from the Kepler Space Telescope probing the many Earth-size planets around the star TRAPPIST-1.

In February, data from the Spitzer Space Telescope revealed that seven planets orbit the ultracool dwarf star, and now, the recently released Kepler data (and its final, processed version) will give a complementary look at the worlds, three of which might orbit in the star’s habitable zone.

Kepler’s observations could provide more detail about the gravitational interactions among the planets, and perhaps reveal even more planets around the star, NASA officials said in a statement

As part of its K2 mission, Kepler examined the TRAPPIST-1 system from Dec. 15, 2016, to March 4, 2017 — and its data became much more exciting upon the Feb. 22 announcement of additional Earth-size planets orbiting the star. Yesterday (March 8), Kepler researchers released the unprocessed data from that survey for astronomers to use in preparing research proposals. 

“Scientists and enthusiasts around the world are invested in learning everything they can about these Earth-size worlds,” Geert Barentsen, K2 research scientist at NASA’s Ames Research Center in California, said in the NASA statement. “Providing the K2 raw data as quickly as possible was a priority to give investigators an early look so they could best define their follow-up research plans. We’re thrilled that this will also allow the public to witness the process of discovery.”

The release is timely because many proposals to study TRAPPIST-1 this winter with ground-based telescopes are due this month, the statement said.

On the Kepler website, Barentsen encouraged scientists to dig into the results and blog or tweet analysis, but advised everyone to wait until the final, processed results are released in late May to cite them in journal papers.

Barentsen also included a preliminary graph of the light curve, the way the star darkened as planets passed across it, which shows hints of at least six planets (as well as star spots) visible in the data.

When K2’s December-March observation plan was established, TRAPPIST-1’s planets were unknown, and the star system wasn’t on the list for investigation. But researchers found evidence of three planets around the star in May 2016, so the Kepler team adjusted the mission to include the newly exciting target.

“We were lucky that the K2 mission was able to observe TRAPPIST-1,” Michael Haas, science office director for the Kepler and K2 missions at Ames, said in the statement. “The observing field for Campaign 12 [the December-March campaign] was set when the discovery of the first planets orbiting TRAPPIST-1 was announced, and the science community had already submitted proposals for specific targets of interest in that field.

“The unexpected opportunity to further study the TRAPPIST-1 system was quickly recognized, and the agility of the K2 team and science community prevailed once again,” Haas added.

Kepler’s original and K2 missions have been responsible for more than 2,400 confirmed exoplanet discoveries. The space telescope uses extremely precise measurements of stars’ brightness over time to identify little dips in brightness that indicate planets in front of the star, called the transit method of exoplanet detection.

Although the transit method can identify only planets that are oriented to pass by the star from Earth’s point of view, it’s an extremely powerful technique. The Spitzer Space Telescope, which counted the seven planets around TRAPPIST-1, used a similar process measuring infrared light.

NASA’s upcoming James Webb Space Telescope, another infrared telescope, could give researchers an even more detailed view of the planets, and help scientists measure whether those potentially habitable ones have atmospheres friendly to life. The telescope will be powerful enough to analyze the light passing from the star through the planets’ atmospheres, letting researchers determine their composition.

Courtesy-Space

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