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« Reply #15 on: Jul 01, 2015, 05:21 AM »

Even really old stars have Earth-like planets

June 30, 2015
Brett Smith for redOrbit.com – @ParkstBrett

If there is another civilization out there in the universe like our own, it may have had a couple billion years head start on us.

According to a new study published in Monthly Notices of the Royal Astronomical Society, several distant stars with Earth-like planets are around 11 billion years old – that’s about 6.5 billion years older that the Sun.

The study is based on an examination of 33 stars with Earth-like planets identified by NASA’s Kepler satellite. For each star, researchers were able to determine age, density, diameter, mass, and distance from Earth with more precision than ever.

“Our team has determined ages for individual host stars before with similar levels of accuracy, but this constitutes the best characterized set of exoplanet host stars currently available,” study author Victor Silva Aguirre, from the Stellar Astrophysics Centre at Aarhus University in Denmark, said via press release.

Measuring like an earthquake

Stars examined in the study are actually solar-like oscillators that send out waves like the sound waves emanating from a stereo or musical instrument.

“The term solar-like oscillators means that the stars exhibit pulsations excited by the same mechanism as in the Sun: gas bubbles moving up and down,” Silva Aguirre said. “These bubbles produce sound waves that travel across the interior of stars, bouncing back and forth between the deep interior and the surface producing tiny variations in the stellar brightness.”

Study researchers were able to pick up these vibrations through asteroseismology – a technique similar to the one geologists use to map out the structure of the Earth’s interior during earthquakes. By inputting data of oscillation frequencies and average asteroseismic parameters, the researchers were able to parse information about each star with unprecedented accuracy.

While the study incorporated just a small section of the sky near the constellation Cygnus, the research team said it’s reasonable to conclude there are countless stars older than our Sun with Earth-like planets in the universe.

“One of the biggest questions in astrophysics is: does life exists beyond earth? To even begin answering this, we need to know how many planets like ours exist out there, and when they formed,” Silva Aguirre said. “The stars we studied harbor exoplanets of size comparable to earth, and our results reveal a wide range of ages for these host stars, both younger, as low as half the Sun’s age, and up to 2.5 times the age of the Sun.”
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« Reply #16 on: Jul 01, 2015, 05:22 AM »

Even really old stars have Earth-like planets

June 30, 2015
Brett Smith for redOrbit.com – @ParkstBrett

If there is another civilization out there in the universe like our own, it may have had a couple billion years head start on us.

According to a new study published in Monthly Notices of the Royal Astronomical Society, several distant stars with Earth-like planets are around 11 billion years old – that’s about 6.5 billion years older that the Sun.

The study is based on an examination of 33 stars with Earth-like planets identified by NASA’s Kepler satellite. For each star, researchers were able to determine age, density, diameter, mass, and distance from Earth with more precision than ever.

“Our team has determined ages for individual host stars before with similar levels of accuracy, but this constitutes the best characterized set of exoplanet host stars currently available,” study author Victor Silva Aguirre, from the Stellar Astrophysics Centre at Aarhus University in Denmark, said via press release.

Measuring like an earthquake

Stars examined in the study are actually solar-like oscillators that send out waves like the sound waves emanating from a stereo or musical instrument.

“The term solar-like oscillators means that the stars exhibit pulsations excited by the same mechanism as in the Sun: gas bubbles moving up and down,” Silva Aguirre said. “These bubbles produce sound waves that travel across the interior of stars, bouncing back and forth between the deep interior and the surface producing tiny variations in the stellar brightness.”

Study researchers were able to pick up these vibrations through asteroseismology – a technique similar to the one geologists use to map out the structure of the Earth’s interior during earthquakes. By inputting data of oscillation frequencies and average asteroseismic parameters, the researchers were able to parse information about each star with unprecedented accuracy.

While the study incorporated just a small section of the sky near the constellation Cygnus, the research team said it’s reasonable to conclude there are countless stars older than our Sun with Earth-like planets in the universe.

“One of the biggest questions in astrophysics is: does life exists beyond earth? To even begin answering this, we need to know how many planets like ours exist out there, and when they formed,” Silva Aguirre said. “The stars we studied harbor exoplanets of size comparable to earth, and our results reveal a wide range of ages for these host stars, both younger, as low as half the Sun’s age, and up to 2.5 times the age of the Sun.”


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« Reply #17 on: Jul 01, 2015, 05:24 AM »

Happy first-ever Asteroid Day!

June 30, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Astronomers and space enthusiasts will be looking to the skies in search of near-Earth objects as part of the first-ever Asteroid Day on Tuesday – an event described by the organizers as a global awareness movement to learn how to protect ourselves from falling planetoids.

According to the event’s website, June 30 was chosen to be Asteroid Day because it was the day of the largest asteroid impact in recent Earth history, the 1908 Siberian Tunguska event. The goal of the event, the organizers told NBC News, is to increase awareness of potential asteroid-related threats and to focus on what to do should we face the threat of another massive impact.

Tom Jones, a planetary scientist and former NASA astronaut who’s an adviser for Asteroid Day, explained that nuclear-scale meteor blast which took place in Chelyabinsk, Russia back in 2013 was a wake-up call of sorts – a “crystallizing event for people who hadn’t been paying attention to the asteroid threat,” as he told NBC.

“Chelyabinsk isn’t in the news cycle anymore, but I don’t think the public has lost sight of the idea that we are repeatedly struck by asteroids,” he added. “The goal of Asteroid Day is to translate that awareness from Chelyabinsk… into ongoing support for government efforts and volunteer efforts to find asteroids… and have a plan on the shelf to do something about them.”

A petition calling for expanded anti-asteroid efforts

At the heart of Asteroid Day is an online petition, the 100X Declaration, which is calling for the world’s governments to “safeguard our families and quality of life on Earth” through the creation of programs to protect the planet from potential asteroid impacts.

“Unlike other natural disasters, we know how to prevent asteroid impacts,” the petition reads. “There are a million asteroids in our solar system that have the potential to strike Earth and destroy a city, yet we have discovered less than 10,000 – just one percent – of them. We have the technology to change that situation.”

They are calling for governments and space programs to use that technology to better detect and track Near-Earth objects that threaten populated parts of the planet; to increase efforts to discover and monitor close asteroids by 100-found, to 100,000 per year by 2025; and to adopt Asteroid Day as an official global holiday to further heighten awareness of the asteroid impact issue.

The petition has been signed by the likes of Bill Nye, science educator and head of the Planetary Society; astrophysicist and Queen guitarist Brian May; Carolyn Shoemaker, astronomer and co-discoverer of the Shoemaker-Levy comet; Brian Cox, particle physics professor at the University of Manchester; and former NASA Director of Operations in Russia Chris Hadfield.

A full list of Asteroid Day events can be viewed online at the event’s website.

Click to watch: https://www.youtube.com/watch?v=RMh4eeh79bs


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« Reply #18 on: Jul 02, 2015, 06:17 AM »

Type Ia supernova observed in ultraviolet light

July 1, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Astrophysicists refer to Type Ia supernovae as “standard candles” because they are used to measure distances of objects throughout the universe, but are they really all the same? That’s what the authors of a new Nature study wanted to find out.

Researchers from the California Institute of Technology (Caltech) and the Weizmann Institute of Science joined forces recently to study more about these supernovae using a robotic telescope array located to observe a star just four days into an explosion.

Using instruments at the Palomar Transient Factory, they spotted the young supernova, and used NASA’s Swift Space Telescope to observe the blast in the invisible ultraviolet range. Thanks to these observations, the researchers were able to detect a brief but never-before-seen spike in the high-energy radiation early on in the supernova process.

UV observations shed new light on how supernovae happen

According to Professor Avishay Gal-Yam from the Weizmann Institute’s Particle Physics and Astrophysics Department, this increase fits with a model in which a dwarf star has a companion. The white dwarf, the professor explained, “is the mass of the Sun packed into a sphere the size of the Earth, while its companion is around 50-100 times bigger around than the Sun.”

The researchers explained that material flowed from the diffuse star to the denser one until the pressure from the added mass eventually caused the smaller of the two stars to detonate. They added that the radiation spike was caused by the initial material ejected during the blast hitting the companion star.

The findings demonstrate the importance of the ultraviolet-range observations of the exploding star. Gal-Yam said he is hopeful that the ULTRASAT mini-satellite currently in the works at the Weizmann Institute, the Israeli Space Agency, and NASA, can used observations in the UV range to determine if this process is common amongst type Ia supernovae.

“Ultraviolet is crucial, because initially, supernova blasts are so energetic that the most important information can only be gathered in short wavelengths. And it can only be seen from a space telescope, because the ultraviolet wavelengths are filtered out in the Earth’s atmosphere,” added Gal-Yam.


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« Reply #19 on: Jul 02, 2015, 06:19 AM »

Universe may end in ‘Big Rip,’ study suggests

July 1, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Researchers from Vanderbilt University in Nashville have come up with a new mathematical formulation that they say will help reconcile the classic notion of viscosity based on the laws of thermodynamics with Einstein’s general theory of relativity.

Their work, published earlier this year in the journal Physical Review D, should help determine just how “sticky” the universe is by explaining cosmological viscosity in a “simpler” and “more elegant” way while still being “mathematically sound” and obeying “all the applicable physical laws,” study co-author and physics professor Robert Scherrer said in a statement.

The new formula was developed by Marcelo Disconzi, an assistant professor of mathematics at Vanderbilt, along with Scherrer and fellow physics professor Thomas Kephart. It addresses the issues with cosmological viscosity by starting with the issue of relativistic fluids, a phenomenon produced by supernovae and the crushed, planet-sized stars known as neutron stars.

While scientists have previously successfully modeled what happens with ideal fluids, or those with no viscosity, most fluids are viscous in nature, and to date, nobody has managed to devise an accepted way to handle viscous fluids traveling at relativistic velocities. Past models used to predict what happens when these realistic fluids are accelerated to a fraction of the speed of light have been plagued by multiple blatant inconsistencies.

Building upon previous studies of cosmological viscosity

The problems with these models inspired Disconzi to tweak the equations of relativistic fluid dynamics in such a way that it does demonstrate those inconsistencies, including one glaring flaw in which they predicted conditions where these fluids were capable of traveling faster than the speed of light, which the professor called “disastrously wrong.”

“Strictly speaking, I did not come up with the formulation myself,” he told redOrbit via email. Rather, he said that he demonstrated that a previous proposal advanced by mathematician André Lichnerowicz in the 1950s “is a viable candidate for a theory of relativistic viscous fluids,” then teamed up with Scherrer and Kephart to “investigate formalism in the context of cosmology.”

“It is not known how to describe viscous fluids in the context of general relativity (GR),” he continued. “Over the years different approaches have been proposed,” including the Mueller-Israel-Stewart theory. While that proposal “does lead to a satisfactory description” in several situations, Disconzi explained that it also “contains some ad hoc features and ultimately does not completely rule out the existence of faster-than-light signals.”

Disconzi said that Lichnerowicz’s proposal remained largely unnoticed until he published a paper on the topic last year. That study “by no means settles the question of what the correct formulation of relativistic viscous fluids is,” he told redOrbit. “What it shows is that, under some assumptions, the equations put forward by Lichnerowicz have solutions and the solutions do not predict faster-than-light signals. But we still don’t know if these results remain valid under the most general situations relevant to physics.”

Implications for dark energy, ultimate fate of the universe

The formula described in the new study could also have significant implications for the ultimate fate of the universe, the university explained in a statement. Furthermore, it could shed new light on the basic characteristics of the unusual form of repulsive energy known as “dark energy,” the substance used to explain the accelerating expansion of the cosmos.

Since it was first discovered in the 1990s, there have been several theories that have attempted to explain the nature of dark energy, but most of them have failed to account for cosmic viscosity, the study authors explained. Disconzi said that it’s possible, but unlikely, that viscosity might be able to account for all of the acceleration that has been attributed to dark energy. It is more likely responsible for at least “a significant fraction of the acceleration,” he added.

Furthermore, the study also seems to support a radical scenario designed to address the ultimate fate of the universe, known as the “Big Rip.” This scenario proposes that the universe contains a phantom-type of dark energy that grows stronger over time, causing the expansion rate of the universe to become so great that material objects ultimately fall apart, causing individual atoms to disassembled and themselves into unbound elementary particles and radiation.

In this scenario, the universe will fall apart if the ratio between the pressure and density of dark energy (its equation of state parameter) falls below -1 – a value known by cosmologists as the “phantom barrier.” In previous models with viscosity, the “Big Rip” was impossible, because the universe could not evolve beyond the limit. In the new formulation, however, the barrier does not exist and viscosity actively drives the universe towards this specific end state.

So does that make the “Big Rip” scenario the most likely scenario when discussing the ultimate fate of the universe? “The fair answer is that nobody really knows,” Disconzi explained to redOrbit. “What is known from current observational data is that a ‘Big Rip’ scenario is possible, although the available data is far from conclusive. What our paper brings to the discussion is a mechanism that yields a ‘Big Rip’ in a fairly natural way, in contrast of most models of the ‘Big Rip’ where unnatural or ad hoc assumptions have to be introduced.”


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« Reply #20 on: Jul 02, 2015, 06:23 AM »


The Christian Science Monitor

Why is NASA sending a boomerang to Mars?

NASA reveals plans to test the 'Prandtl-m' plane for future use on the red planet.

By Shontee Pant, Staff writer July 1, 2015   

NASA’s Armstrong Flight Research Center announced on Tuesday that it has plans to drop its Preliminary Research Aerodynamic Design to Land on Mars (Prandtl-m), a glider-like structure, from a high altitude balloon at the height of 100,000 feet this year.

"The aircraft would be part of the ballast that would be ejected from the aeroshell that takes the Mars rover to the planet," said Al Bowers, NASA Armstrong chief scientist and Prandtl-m program manager, in the NASA press release.

The spacecraft has a wingspan of two feet and would weigh less than a pound on Mars due to the lower gravitational pull on the red planet (on Earth it weighs 2.6 pounds). The glider will be created from either fiberglass or carbon fiber and would be able to fly for around 10 minutes.

The research group will attach either a mapping camera or a small, high-altitude radiometer to measure radiation at very high altitudes of Earth's atmosphere on the first balloon drop test. In the future, the team hopes to be able to attach both. Cameras could scan and take high-resolution photos of the surface they are covering, which would give more information to future manned-missions to Mars, including the potential Mars One mission.

The glider could travel, folded up, in a CubeSat – a small, box-like “nanosatellite” which has a volume of a quart and weigh close to three pounds. There is a mission going to Mars sometime between 2022 and 2024, and the glider would go along for the ride.

“The balloon would drop the CubeSat container and then the aircraft would deploy from the container right after the drop, unfold and fly away," said Mr. Bowers in the NASA press release. 

Three tests are scheduled for the Prandtl-m glider, including two balloon-drop tests on Earth and a possible sounding rocket flight to demonstrate how the glider would work on Mars. Sounding rocket flights enable scientists to test how objects on flights would react to a variety of space-like circumstances, as the rocket carries payloads 30 to 800 miles off the ground. The payload tests are simple, cost-effective, and efficient. One of the largest advantages from a monetary standpoint is that pieces of the rocket tested are retrievable.

The sounding rocket test would carry the rocket with the CubeSat attached and the glider inside, just as in the real launch. The rocket would launch to a height of 450,000 feet and then release the CubeSat. The glider would deploy at the 110,000-to-115,000-feet altitude range, just as though the mission were on Mars. Bowers credits the Prandtl-m concept to Dave Berger, a NASA Armstrong aeronautical engineer with the Education Office.

In 2014, the Armstrong Research Center at NASA worked on a Towed Glider Air-Launch System (TGALS), with the goal of creating a relatively inexpensive remotely or optionally piloted glider that could be towed by a large transport aircraft into space, and would be released at around 40,000 feet. The glider would hold a booster rocket that would help it enter into low Earth orbit. However, the current glider design is the first to be created for Mars.

"If the Prandtl-m completes a 450,000-foot drop, then I think the project stands a very good chance of being able to go to NASA Headquarters and say we would like permission to ride to Mars with one of the rovers." said Bowers.


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« Reply #21 on: Jul 02, 2015, 06:29 AM »

Christian Science Monitor

NASA zeroes in on Pluto, detects frozen methane

As NASA's New Horizons makes final preparations to zoom past Pluto, the probe continues to make startling observations.

By Michelle Toh, Staff writer July 1, 2015   

As NASA’s New Horizons spacecraft closed in on Pluto’s surface, two weeks before its rendezvous with the ex-planet, it detected a substance scientists had long suspected was there: frozen methane.

Astronomers in California had first observed the chemical compound on Pluto in 1976.

But Will Grundy, the New Horizons Surface Composition team leader with the Lowell Observatory, said Tuesday’s detection was the first confirmation of their observations. “Soon we will know if there are differences in the presence of methane ice from one part of Pluto to another,” he said in a statement.
Recommended: Are you scientifically literate? Take our quiz

NASA said Pluto’s methane may have always been there, “inherited from the solar nebula from which the solar system formed 4.5 billion years ago.”

The New Horizons spaceship will whiz past Pluto on July 14 “in a flyby that will give humanity its first up-close look at Pluto and its moons,” The Christian Science Monitor's Pete Spotts wrote in April.

So many questions surround the system that it presents “a scientific wonderland,” Alan Stern, lead scientist for the mission, told the Monitor.

Satellite photographs from the $700 million mission have already offered extraordinary glimpses at the dwarf planet that scientists speculate is even redder than Mars, with rivers of liquid neon flowing across the surface and a subsurface liquid-water ocean.

The latest image of Pluto and its largest moon, Charon, shows only two icy gray circles to the undiscriminating eye, but scientists have already detected new details.

“Pluto and Charon are becoming more distinct in their surface features,” Alice Bowman, the missions operations manager for New Horizons, said Tuesday in a mission update.

To ensure each instrument is in position for the historic encounter on the 14th, the spacecraft is undergoing final, minute adjustments, said mission design lead Yanping Guo of the Johns Hopkins Applied Physics Laboratory. Tuesday's 23-second thruster burn kept New Horizons from arriving 20 seconds late and 114 miles off-target.

In addition, obstacles like icy debris are dealt with en route, NASA said.

"Our team has worked hard to get to this point, and we know we have just one shot to make this work," said Ms. Bowman in April. "We’ve plotted out each step of the Pluto encounter, practiced it over and over, and we’re excited the ‘real deal’ is finally here."


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« Reply #22 on: Today at 05:18 AM »

DARPA engineers organisms to terraform Mars

July 2, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

The US Defense Advanced Research Projects Agency (DARPA) is reportedly in the process of developing engineered organisms capable of terraforming the surface of Mars, transforming the Red Planet into a habitable, hospitable environment closer to the Earth.

As RT.com explains, if humans are ever going to live on the Red Planet without simply being stuck inside buildings and synthetic environments, we would have to drastically alter its climate and surface features, which include low gravity, a thin atmosphere, and dangerous dust storms.

In addition, its distance from the sun would make it too cold for mankind to live normally, with temperatures on Mars averaging -50 degrees Celsius (-122 degrees Fahrenheit). The answer may lie in artificially altering the environment by genetically engineering plants and other organisms to heat up the planet, and potentially even thicken the atmosphere.

DARPA, which according to Motherboard has already been investing in genetic engineering and synthetic biology, claims that it is currently working on organisms that could ultimately make the Red Planet the type of place that humanity could someday (in the far off future) call home.

Creating new life forms using only the best genes

As Alicia Jackson, the deputy director of DARPA’s new Biological Technologies Office, said, “For the first time, we have the technological toolkit to transform not just hostile places here on Earth, but to go into space not just to visit, but to stay.”

The technological toolkit Jackson refers to includes research that’s been going on in her team’s lab for the past year, involving how to easily genetically engineer organisms of various types, not just the two most commonly used in synthetic biology projects (yeast and E. coli). Furthermore, DARPA has created new software, DTA GView, which was demonstrated at the conference. Jackson calls it the “Good Maps of genomes,” Motherboard said.

“There are anywhere from 30 million to 30 billion organisms on this Earth. We use two right now for engineering biology,” she explained. “I want to use any organism that has properties I want – I want to quickly map it and quickly engineer it. If you look at genome annotation software today, it’s not built to quickly find engineerable systems [and genes]. It’s built to look for an esoteric and interesting thing I can publish an academic paper on.”

“This torrent of genomic data we’re now collecting is awesome, except they sit in databases, where they remain data, not knowledge. Very little genetic information we have is actionable. With this, the goal is to, within a day, sequence and find where I can best engineer an organism,” Jackson continued, adding that the goal is to make it possible to choose the best genes from different organisms, then mix and match them to create completely new forms of life.

While these advances could be used in the aftermath of a natural or man-made disaster, if it proves successful could also be used on Mars. There, the organisms would ideally make planets like Mars habitable and lead to human colonies on other worlds.


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« Reply #23 on: Today at 05:19 AM »

Has the evolution of extraterrestrial life already happened?

July 2, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Extraterrestrial lifeforms similar to humans should have already evolved on other planets like Earth. This makes it seem all the more odd that we have yet to discover any other civilizations like ours elsewhere in the universe, claims the author of a new book.

Professor Simon Conway Morris, a Fellow at St John’s College, University of Cambridge and the author of a new study on the topic of convergent evolution entitled The Runes of Evolution: How the Universe Became Self-Aware, argues that there is a universal “map of life” which dictates the manner in which all living creatures develop, regardless of their location in the cosmos.

Conway Morris’s book takes an established principle, the theory of convergent evolution (which states that species in different lineages will independently evolve similar features), and expands it. He suggests this type of convergence is common and has helped guide every aspect of life’s development on earth, ranging from the formation of proteins, the development of arms, legs and eyes, our intelligence and ability to use tools, and even how we experience orgasms.

All of these things, he argues, are inevitable once life emerges. As such, evolution is not random, but is instead a predictable process that follows a somewhat strict series of rules. If this is true, then it would indicate that life similar to that found on Earth would have obeyed those same rules and would have developed on other, similar planets, given the proper conditions.

We shouldn’t be alone…but we are

With astronomers discovering an increasing abundance of Earth-like planets located throughout the known universe, Professor Conway Morris said it’s rather extraordinary that we have yet to find any aliens that resemble and behave like us living on another planet – not to mention any life forms similar to the other living things, plants and animals alike, that live here.

He argues not only that if there are any aliens out there in the cosmos, they would be a lot like people in that they would have heads, torsos, and limbs. He also says that any life-bearing Earth-like planet would evolve other creatures similar to those we’re familiar with, and that there would almost undoubtedly be extraterrestrials with brains and human-like intelligence.

“The number of Earth-like planets seems to be far greater than was thought possible even a few years ago,” Professor Conway Morris said in a statement. “That doesn’t necessarily mean that they have life, because we don’t necessarily understand how life originates. The consensus offered by convergence, however, is that life is going to evolve wherever it can.”

“I would argue that in any habitable zone that doesn’t boil or freeze, intelligent life is going to emerge, because intelligence is convergent,” he added. “One can say with reasonable confidence that the likelihood of something analogous to a human evolving is really pretty high. And given the number of potential planets that we now have good reason to think exist, even if the dice only come up the right way every one in 100 throws, that still leads to a very large number of intelligences scattered around, that are likely to be similar to us.”

“The almost-certainty of ET being out there means that something does not add up, and badly,” the professor concluded. “We should not be alone, but we are.”


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« Reply #24 on: Today at 05:20 AM »

Huge sinkholes discovered on Rosetta’s comet

July 2, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Comet 67P/Churyumov–Gerasimenko, better known as the comet being studied by the ESA’s Rosetta spacecraft, is filled with surface pits similar to the sinkholes found on Earth, a team of researchers reported in a paper published Wednesday in the journal Nature.

According to BBC News, Jean-Baptiste Vincent of the Max Planck Institute for Solar System Research in Göttingen, Germany and his colleagues explained in the new study that they believe material located beneath the comet’s surface vaporizes in some areas, causing holes that can no longer support the crust above them.

Vincent said that the collapse of that crust produces cylindrical holes that can be more than 100 meters deep. The largest one, he told the BBC, is roughly 200 meters wide and 200 meters deep, and their discovery “gives us the possibility to look inside the comet for the first time.”

The comet’s pits are believed to form similar to sinkholes on Earth, which occur when rain and other sources of water slowly begin to erode surfaces made out of limestone and similar types of rock. Over time, this results in underground holes that eventually break away the crust above them, allowing them to break through to the surface.

Discovery could reveal the age of the 67P’s surface

Thus far, 18 of these sinkhole-type pits have been located on Comet 67P, all of them located on the northern hemisphere of the four-kilometer wide object. As 67P travels closer towards the sun, it’s believed that buried volatiles will be driven off, opening up more of these hollows, according to BBC News reports.

While these holes may already exist to some degree on the comet, the loss of these volatiles will likely make the situation worse. The dusty ceilings above these voids will be unable to support their own weight, despite the fact that 67P has low-gravity, and will ultimately collapse inwards. This will expose the cavern walls to direct sunlight, causing ice there to melt.

Eventually, they believe these sinkholes will open out into shallow basis, which are also likely to merge. This will allow scientists to better understand how old different types of terrains on the comet are, as regions that are home to several of these pits are also certainly older than those with uncollapsed surfaces.

In their paper, Vincent’s team wrote that the comet’s pits were “probably created by a sinkhole process, possibly accompanied by outbursts. We argue that after formation, pits expand slowly in diameter, owing to sublimation-driven retreat of the walls… The size and spatial distribution of pits imply that large heterogeneities exist in the physical, structural, or compositional properties of the first few hundred meters below the current nucleus surface.”

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