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Was the Origin of Life a Fluke Or Was it Physics?

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?

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.

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

England said, "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

"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 by laws of Physics Was it Physics

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.

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. ( please visit the link , down )

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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 the 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.

"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."

Let's make a discussion about Emergence of life beyond Earth

England said, "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,"

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.

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.

About Image : Understanding the origin of life

Credit : Shutterstock
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Space Plane to Sky Crane: How Part of a Space Shuttle Landed a Rover on Mars

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"We took part of a space shuttle and put it on Mars," said Masashi Mizukami, an engineer at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., in an email interview with collectSPACE. "It was an existing off-the-shelf design that could meet nearly all of the specialized [Mars Science Laboratory] MSL requirements as is."

Hardware from one of NASA's retired space shuttle orbiters played a critical role in the landing of the Curiosity rover on Mars five years ago.

Largely unknown to the public, a helium regulator that first flew multiple times into Earth orbit as part of the propulsion system for the reusable winged spacecraft was inspected, modified, tested and then relaunched as a key component of the descent stage for the six-wheeled rover that touched down on the Red Planet on Aug. 5, 2012 (PDT or Aug. 6 EDT/GMT).

"On the propulsion side, this was one of the few [possible] single point failures on the mission," said John Habis, vice president of business development at VACCO Industries, which sourced the helium regulator for the shuttle program and serviced it for its reuse on MSL. "If this unit had not of worked, there was no backup."

For the rocket-powered portion of the descent, a pressure regulator was needed in order to precisely control the flow rate of the eight thrusters' hydrazine propellant. As a result of other program constraints, the lead time to develop such a component was limited, making an off-the-shelf solution the only real option.

"When JPL came to us, they had already exhausted one or two vendors for this application and they were not getting too far," Habis told collectSPACE. "It was while we were in discussions about other components we were doing for the [MSL] cruise stage that we discovered this opportunity was there, and they discovered what we had and what could be used."

Working across its programs and centres, NASA sourced for MSL three 750 psi helium regulators, including at least one that was extracted from the space shuttle Discovery.

Although based on the same hardware, the shuttle helium regulator needed to serve a different function as part of the Mars spacecraft.

"On MSL, it provided regulated pressure to the descent stage propellant. On the space shuttle orbiter, it provided regulated purge and pneumatic actuator gas for the main engines," explained Mizukami, who was the lead author on a 2009 paper about the reuse of the regulator.

VACCO engineers modified the shuttle hardware with new components and serviced it so it was "like new."

"It really went out of here like it was a new unit from us. The only difference was that the raw material came from the shuttle regulators," said Wicke.

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About: A pressure regulator that flew as part of a NASA space shuttle was reused on the descent stage for the Curiosity rover that landed on Mars five years ago.

Credit: NASA/JPL-Caltech/MSSS/


About : Mars Science Laboratory (MSL) high flow pressure regulator.

Credit: NASA/JPL-Caltech via

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ESA’s light-studded Rover Autonomy Testbed seen during night testing in Tenerife, intended to simulate the low light environment of the lunar poles.

The testbed, operated by a team from GMV in Spain, plus ESA’s Heavy Duty Planetary Rover, overseen by ESA’s planetary robotics team, travelled to the Canary Islands for the day and night testing in the volcanic, Moon-like environment of Teide National Park.

The two rovers carry navigation aids to work in both light and dark, including stereo cameras, lights, GPS, laser rangers and radar-like lidar. They can build digital 3D maps from these various sensors for both autonomous and teleoperated steering.

About Image: RAT rover by night
Credit : Fernando Gandía/GMV Team/ESA/planetary robotics Team

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Wondering why everyone is so sad about the end of NASA's Cassini mission. This picture should help clear things up. This stunning shot (isn't it so "film noir?") shows the Saturnian moons of Titan, Hyperion and Prometheus just beyond the planet's trademark rings. Cassini captured the image on July 14, 2014. More Cassini shots

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NASA's Cassini spacecraft has been snapping amazing photos of Saturn and its moons since 2004. See some of Cassini's latest spectacular photos of the Saturn system here. SHOWN HERE: This image of Saturn, taken by the Cassini probe on Feb. 26, 2016. The spacecraft captured this image from roughly 1.7 million miles, at 16 degrees above the ring plane using its wide-angle camera. The image reveals the planet’s odd hexagonal cloud pattern around the north pole

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This is where stardust comes from

Astronomers have spotted dust from some of the universe’s earliest supernovae, which are responsible for the elements in our Sun and solar system today.

The Atacama Large Millimeter/submillimeter Array (ALMA) in the Chilean Andes has made several groundbreaking discoveries since it was brought online in 2011. Able to image the sky in millimeter and submillimeter wavelengths, ALMA can spot emission associated with molecular gas and dust, which are cold and can be difficult or impossible to see at other wavelengths. Using this ability, ALMA has identified dust and gas in a galaxy that formed when our universe was only about 4 percent of its current age.

The galaxy is called A2744_YD4, and it’s the most distant galaxy ever found by ALMA. It sits at a redshift of 8.38, which is associated with a time when the universe was just 600 million years old.

Redshift measures the amount by which a distant object’s light is stretched by the expansion of the universe. Objects with a higher redshift are farther away, and thus we are looking at them as they appeared in the past. In the very nearby universe, objects have a redshift of nearly zero; high-redshift objects, such as A2744_YD4 with its redshift of 8.38, are extremely far away (the exact distance depends on the expansion history of the universe). It’s also important to note that redshift is not linear — redshifts of 0-1 are considered relatively nearby, while redshifts of 8-9 are some of the farthest objects we can currently see as we look back to the very early universe. The cosmic microwave background was produced at a redshift of about 1,000.

A2744_YD4’s cosmological “timestamp,” as given by its redshift, falls within the estimated age range for the Epoch of Reionization, which occurred somewhere around a redshift of 10, when the universe was about 400 million years old. The Epoch of Reionization is when the universe’s first luminous sources — stars, quasars, and galaxies — turned on and ionized neutral hydrogen atoms (that is, knocked their electrons away). Neutral hydrogen is opaque to short wavelengths of light, which means that it absorbs these wavelengths easily so the light cannot pass through. As neutral hydrogen throughout the universe was ionized, however, light could finally travel vast distances.

The detection of A2744_YD4 and its properties, which was made by an international team of astronomers led by Nicolas Laporte of University College London, is remarkable for several reasons.

A2744_YD4 is full of dust. In the press release accompanying the announcement, Laporte explained that “the detection of so much dust indicates early supernovae must have already polluted this galaxy.” Supernovae are the end result of massive stars, which blow away much of their interiors explosively as they die. Among the material blown away is dust, which is made up of elements such as aluminum, silicon, and carbon, and is spread across galaxies by these explosions. This dust is an integral component of today’s stars (like our Sun) and the planets surrounding them. In the very early universe, however, this dust was scarce, simply because the process of its creation and dispersion via supernovae hadn’t had much time to complete.

But in A2744_YD4, this process has apparently had enough time to progress. A2744_YD4 produces stars at a rate of 20 solar masses per year, which is a full 20 times the rate of our Milky Way’s comparatively paltry star formation rate of 1 solar mass per year. Based upon this rate, the group estimated that only about 200 million years were needed to form the dust seen in A2744_YD4.

Population III (Pop III) stars theoretically contain only hydrogen, helium, and very little if any “heavier” elements, such as lithium. This chemistry makes Pop III stars extremely metal-poor, if not devoid of metals altogether. (As a note, astronomers typically refer to any elements heavier than helium as “metals,” regardless of their classification on the periodic table.) Pop III stars probably began developing about 100 million years after the Big Bang. The metals created inside these massive stars began to spread via supernovae, and as the metal content of the universe increased, Pop II stars began to form about 13 billion years ago. Today, these stars are found in the bulges and haloes of galaxies, and while they’re still considered metal-poor, they contain metal abundances much greater than the very early universe.

The cycle of stellar birth and recycling continued, until about 10 billion years ago, Pop I stars began to form. Our Sun is a Pop I star, and the metals found inside it and our solar system can all be traced back to the same type of supernovae that spread dust (and metals) throughout A2744_YD4.

In addition to identifying the dust from these early supernovae, ALMA also spotted emission from ionized oxygen in A2744_YD4 as well. This is the earliest detection of ionized oxygen in the universe, breaking a previous record also held by ALMA (from a detection made in 2016).

All of this was made possible by the fact that A2744_YD4 sits behind a massive galaxy cluster called Abell 2744, also known as Pandora’s Cluster. The cluster is acting as a gravitational lens, magnifying the image from A2744_YD4 far behind it by about 1.8x and allowing astronomers to study this tiny, faraway galaxy.

These observations of A2744_YD4 and its contents are just an early step in tracing the origins of the universe’s earliest — and perhaps first, and most massive — stars, as well as exploring the epoch when stars and galaxies first began to shine. According to Laporte, “Further measurements of this kind offer the exciting prospect of tracing early star formation and the creation of the heavier chemical elements even further back into the early universe.”

About Images :

1. A2744_YD4 is so far away that it appears as a tiny smudge sitting behind the rich galaxy cluster Abell 2744. Shown in red are the ALMA observations that allowed Laporte and his team to identify dust throughout the galaxy.

Credits : ALMA (ESO/NAOJ/NRAO), NASA, ESA, ESO and D. Coe (STScI)/J. Merten (Heidelberg/Bologna)

2. ALMA observations have uncovered an extremely young, dusty galaxy already polluted with the products of supernovae, as pictured in this artist’s impression.

Credits : ESO/M. Kornmesser

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Saturn's Ravioli Moon

Saturn's moon Pan resembles a frozen ravioli in this new image from NASA's Cassini spacecraft. Pan is about the size of New York City and is the innermost known moon orbiting Saturn. Cassini flew within 15,268 miles (24,572 kilometers) of the strangely-shaped moon on Tuesday (March 7) and captured the closest images of the satellite to date. — Hanneke Weitering

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Credits : NASA/JPL-Caltech/Space Science Institute
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Hubble solves the mystery bulge at the center of the Milky Way

Our supermassive black hole has been on a diet for millions of years… but when did it last splurge

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The Milky Way appears as a relatively flat structure when viewed along its plane in visible light. Gamma-ray emission, however, paints a different picture: two huge structures billowing outward from the galaxy’s bulge like an enormous hourglass. Named the Fermi Bubbles, these structures are the result of the Milky Way’s supermassive black hole gorging itself on interstellar gas in the past. Using the Hubble Space Telescope (HST), astronomers have now determined just when these structured formed.

A team of astronomers led by Rongmon Bordoloi of the Massachusetts Institute of Technology has used distant quasars to trace the structure and motion of the northern Fermi Bubble, which rises 23,000 light-years above the plane of the Milky Way and contains enough cool gas to create 2 million Sun-size stars. By observing the ultraviolet light from 46 quasars with the Cosmic Origins Spectrograph (COS) on HST (and adding one quasar observation with HST’s Space Telescope Imaging Spectrograph), the team mapped out the motions of cool gas within the bubble to pin down its age: 6 to 9 million years.

Most galaxies contain a supermassive black hole at the center, and our Milky Way is no exception. Sgr A* resides in the Milky Way’s bulge and has a mass equivalent to 4.5 million solar masses. Today, Sgr A* is relatively quiet, accreting slowly as the galaxy ages. By contrast, quasars are young, massive supermassive black holes at the centers of galaxies in the early universe, sucking down huge amounts of gas and dust that shine brightly as the material is funneled into an accretion disk before finally passing into the black hole. Like these younger black holes, astronomers believe that our own supermassive black hole was once more active, at a time when the galaxy was still forming and material was more plentiful for accretion.

Sometimes, though, material doesn’t actually make it all the way into the black hole. Matter can escape along the black hole’s spin axis, exiting the area — and often the galaxy altogether — as huge outflows that span tens or hundreds of thousands of light-years. The Milky Way’s Fermi Bubbles are such an outflow; they were discovered in 2015 and named after NASA’s Fermi Gamma-Ray Telescope, which spotted them.

Learning more about the origins of these outflows requires information about their motion. “We have traced the outflows of other galaxies, but we have never been able to actually map the motion of the gas,” said Bordoloi in a press release announcing his group’s results. The work also appeared in the January 10, 2017 edition of The Astrophysical Journal. “The only reason we could do it here is because we are inside the Milky Way. This vantage point gives us a front-row seat to map out the kinematic structure of the Milky Way outflow.”

As the quasars’ light travels through the bubble to reach Earth, it highlights the gas in bubble itself, allowing astronomers to determine information such as its chemical composition, temperature, and motion. The “cool” gas in the northern Fermi Bubble, which contains elements such as silicon and carbon, was clocked at 2 million miles per hour (3 million kph) an reaches temperatures of 17,700 degrees Fahrenheit (9,800 degrees Celsius).

Such cool gas is actually likely gas from the disk of the galaxy that has been swept up by and integrated into the outflow itself, which has temperatures of up to 18 million degrees F (nearly 10 million degrees C). It is these high temperatures that cause the gas to shine in energetic light, such as gamma rays.

Once the gas’ motion — its direction of movement and velocity — was measured, astronomers used this data to turn back the clock and pinpoint when the gas started moving. This origin is also the last known “big meal” enjoyed by Sgr A*, which hasn’t managed to suck down such a significant amount of matter ever since.

“What we find is that a very strong, energetic event happened 6 million to 9 million years ago,” Bordoloi explained. “It may have been a cloud of gas flowing into the black hole, which fired off jets of matter, forming the twin lobes of hot gas seen in X-ray and gamma-ray observations. Ever since then, the black hole has just been eating snacks.”

About Image : The Fermi Bubbles are two huge structures “burped out” by the Milky Way’s supermassive black hole and visible in X-ray and gamma-ray light.

Credits : NASA's Goddard Space Flight Center
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Multiwavelength View of Supernova 1987A

Astronomers combined observations from three different observatories to produce this colorful, multi-wavelength image of the intricate remains of Supernova 1987A.

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The red color shows newly formed dust in the center of the supernova remnant, taken at submillimeter wavelengths by the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile.

The green and blue hues reveal where the expanding shock wave from the exploded star is colliding with a ring of material around the supernova. The green represents the glow of visible light, captured by NASA’s Hubble Space Telescope. The blue color reveals the hottest gas and is based on data from NASA’s Chandra X-ray Observatory.

The ring was initially made to glow by the flash of light from the original explosion. Over subsequent years the ring material has brightened considerably as the explosion’s shock wave slams in it.

Supernova 1987A resides 163,000 light-years away in the Large Magellanic Cloud, where a firestorm of star birth is taking place.

The ALMA, Hubble, and Chandra images at the bottom of the graphic were used to make up the multiwavelength view.

Credits :

Image credit: NASA, ESA, and A. Angelich (NRAO/AUI/NSF)
Hubble credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation)
Chandra credit: NASA/CXC/Penn State/K. Frank et al.
ALMA credit: ALMA (ESO/NAOJ/NRAO) and R. Indebetouw (NRAO/AUI/NSF)

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Partial Eclipse Taken by Proba-2's SWAP imager

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The European Space Agency's Proba-2 satellite captured a partial solar eclipse from space on Feb. 26. Meanwhile, observers in Earth's southern hemisphere enjoyed an annular solar eclipse, in which the moon blocked the sun and created a "ring of fire" in the sky. From Proba-2's point of view, the moon crossed the sun off-center and appeared to take a bite out of its shining face. This image was taken by Proba-2's SWAP imager, which observes the sun in ultraviolet light to capture its turbulent surface and its swirling corona. — Hanneke Weitering

Credit : ESA/Royal Observatory of Belgium
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Weird Asteroid Split in Half and Grew Glowing Dust Tails

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A recently discovered "asteroid pair" is the youngest such duo known in Earth's solar system, and it appears to have sprouted twin comet-like tails, new observations reveal.

This asteroid pair, known as P/2016 J1, was discovered in 2016. Asteroid pairs are not uncommon in the solar system's main asteroid belt. These duos typically form when a parent asteroid breaks in two pieces following a collision with a foreign body, or when the rocky body experiences an excess rotational speed or destabilization of its initial orbit, scientists have said.

The new observations of were made by researchers using the Great Telescope of the Canary Islands (GTC) and the Canada-France-Hawaii Telescope (CFHT) on Hawaii's Mauna Kea volcano. The team found "that the asteroid fragmented approximately six years ago, which makes it the youngest known asteroid pair in the solar system to date," project leader Fernando Moreno, a researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC) in Spain, said in a statement.

When studying P/2016 J1, astronomers discovered that the asteroid pair was activated between the end of 2015 and the beginning of 2016, when the space rocks reached perihelion — the point in their orbit when they are closest to the sun. They remained that way for roughly six to nine months. Their activation is a separate event from that which caused the asteroid to break in half, according to the statement.

Although the two members of the asteroid pair are not gravitationally linked, the rocky bodies have similar orbits around the sun, the researchers said. P/2016 J1 travels in a quasi-circular orbit between Mars and Jupiter, and therefore doesn't get close enough to the sun to experience the temperature changes that create the dust tails observed on comets, the scientists said.

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Instead, the new observations suggest that "the dust emission is due to the sublimation [shift from solid to gaseous phase] of ice that was left exposed after the fragmentation," Moreno said in the statement from the IAA-CSIC.

About Image :

1. Hubble Space Telescope view showing the dust tail of the "activated asteroid" P/2013 P5. Astronomers have recently spotted tails coming from the youngest-known fragmented asteroid pair in the solar system, a duo known as P/2016 J1.

Credit: NASA/ESA

2. These observations of the two asteroid fragments that make up P/2016 J1 (called J1-A and J1-B) from May 15, 2016 show the central regions of the space rocks, as well as the diffuse blots of their dust tails.

Credit: IAA-CSIC

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