Quasars May Answer How Starburst Galaxies Were Extinguished

Some of the biggest galaxies in the universe are full of extinguished stars. But nearly 12 billion years ago, soon after the universe first was created, these massive galaxies were hotspots that brewed up stars by the billions.
How these types of cosmic realms, called dusty starburst galaxies, became galactic dead zones is an enduring mystery.

Astronomers at the University of Iowa, in a new study published in the Astrophysical Journal, offer a clue. They say quasars, powerful energy sources believed to dwell at the heart of galaxies, may be responsible for why some dusty starburst galaxies ceased making stars.

The study could help explain how galaxies evolve from star makers to cosmic cemeteries and how various phenomena scientists know little about—quasars and supermassive black holes that are believed to exist deep within all galaxies, for example—may propel those changes.

The scientists arrived at their theory after locating quasars inside four dusty starburst galaxies that still are creating stars.

“These quasars may play an important role in making the dusty starbursts extinct in the cosmic history,” says Hai Fu, assistant professor in the UI’s Department of Physics and Astronomy and the paper’s first author. “This is because quasars are energetic enough to eject gas out of the galaxy, and gas is the fuel for star formation, so quasars provide a viable mechanism to explain the transition between a starburst and an extinct elliptical (galaxy).”

Quasars shouldn’t be detectable in dusty starburst galaxies because their light would be absorbed, or blocked, by the grit churned up by the intense star-forming activity taking place there, Fu says.

“So, the fact that we saw any such quasars implies that there must be more quasars hidden in dusty starbursts,” Fu says. “To push this to the extreme, maybe every dusty starburst galaxy hosts a quasar and we just cannot see the quasars.”

Fu and his team located the quasars in March 2016 with the Atacama Large Millimeter/submillimeter Array (ALMA), a bank of radio telescopes located more than 16,000 feet above sea level in northern Chile. It was the first time Fu’s team reserved time on ALMA, brought into full operation in 2013 and funded by international partners, including the U.S. National Science Foundation.

The scientists then mapped the quasars with other telescopes and at wavelengths ranging from ultraviolet to far infrared. Based on these observations, they confirmed the quasars are the same as those located with ALMA. The question then became: Why are these quasars visible when they should be enshrouded?

The researchers have a theory. They think the quasars are peeking out from deep holes in each galaxy, a debris-less vacuum that allows light to escape amid the cloudy surroundings. The specific shape of these galaxies is unclear because even ALMA isn’t powerful enough to provide a clear look at regions of the cosmos where light being detected was emitted 12 billion years ago, when the universe was roughly one-seventh its current age. But the team imagines the galaxies may be doughnut shaped and oriented in such a way that their holes (and, thus, the quasar) can be seen.

“It’s a rare case of geometry lining up,” says Jacob Isbell, a UI senior from Garrison, Iowa, majoring in physics and astronomy and the paper’s second author. “And that hole happens to be aligned with our line of sight.”
The scientists now think most quasars inside dusty starburst galaxies can’t be seen because they’re oriented in a way that keeps them hidden. But finding four examples of dusty starburst galaxies with viewable quasars does not seem random; in fact, it suggests more exist.

The paper is titled, “The circumgalactic medium of submillimeter galaxies. II. Unobscured QSOS within dusty starbursts and QSO sightlines with impact parameters below 100 kiloparsec.”

Planetary Defense Campaign Will Use Real Asteroid For The First Time

For the first time, NASA will use an actual space rock for a tabletop exercise simulating an asteroid impact in a densely populated area. The asteroid, named 2012 TC4, does not pose a threat to Earth, but NASA is using it as a test object for an observational campaign because of its close flyby on Oct. 12, 2017.

NASA has conducted such preparedness drills rehearsing various aspects of an asteroid impact, such as deflection, evacuation, and disaster relief, with other federal entities in the past. Traditionally, however, these exercises involved hypothetical impactors, prompting Vishnu Reddy of the University of Arizona’s Lunar and Planetary Laboratory to propose a slightly more realistic scenario, one that revolves around an actual near-Earth asteroid, or NEA.

“The question is, how prepared are we for the next cosmic threat?” says Reddy, an assistant professor of planetary science at the Lunar and Planetary Laboratory. “So we proposed an observational campaign to exercise the network and test how ready we are for a potential impact by a rogue asteroid.”

NASA’s Planetary Defense Coordination Office (PDCO), the federal entity in charge of coordinating efforts to protect Earth from hazardous asteroids, accepted Reddy’s proposal to conduct an observational campaign as part of assessing its Earth-based defense network. Reddy will assist Michael Kelley, who serves as a program scientist with NASA PDCO and the civil servant lead on the exercise.

The goal of the TC4 exercise is to recover, track, and characterize 2012 TC4 as a potential impactor in order to exercise the entire system from observations, modeling, prediction, and communication.

Measuring between 30 and 100 feet, roughly the same size as the asteroid that exploded over Chelyabinsk, Russia, on Feb. 15, 2013, TC4 was discovered by the Pan-STARRS 1 telescope on Oct. 5, 2012, at Haleakala Observatory on Maui, Hawaii. Given its orbital uncertainty, the asteroid will pass as close as 6,800 kilometers (4,200 miles) above Earth’s surface.

“This is a team effort that involves more than a dozen observatories, universities, and labs across the globe so we can collectively learn the strengths and limitations of our planetary defense capabilities,” said Reddy, who is coordinating the campaign for NASA PDCO.

Since its discovery in 2012, the uncertainty in the asteroid’s orbit has slowly increased, as it would for any asteroid as time passes. Therefore, the first order of business will be to “recover” the object—in other words, nail down its exact path. Reddy and his collaborators hope that depending on its predicted brightness, the asteroid would be visible again to large ground-based telescopes in late August.

“One of the strengths of UA research is partnering with federal agencies or industry to work together in solving some of the grand challenges we face,” said Kimberly Andrews Espy, senior vice president for research. “This project is a perfect example of matching UA capabilities—from our world-class imaging to our expertise in space sciences—with an external need.”

The UA is home to the Catalina Sky Survey, one of the most prolific asteroid discoverers, and the Spacewatch project that recovers and tracks faint NEAs. Both teams will take part in the planetary defense exercise.

Eclipse Balloons To Study Effect Of Mars-Like Environment On Life

Steps forward in the search for life beyond Earth can be as simple as sending a balloon into the sky. In one of the most unique and extensive eclipse observation campaigns ever attempted, NASA is collaborating with student teams across the U.S. to do just that.

A larger initiative, NASA’s Eclipse Balloon Project, led by Angela Des Jardins of Montana State University, is sending more than 50 high-altitude balloons launched by student teams across the U.S. to livestream aerial footage of the Aug. 21 total solar eclipse from the edge of space to NASA’s website.

“Total solar eclipses are rare and awe-inspiring events. Nobody has ever live-streamed aerial video footage of a total solar eclipse before,” said Angela Des Jardins. “By live-streaming it on the Internet, we are providing people across the world an opportunity to experience the eclipse in a unique way, even if they are not able to see the eclipse directly.”

A research group at NASA’s Ames Research Center, in California’s Silicon Valley, is seizing the opportunity to conduct a low-cost experiment on 34 of the balloons. This experiment, called MicroStrat, will simulate life’s ability to survive beyond Earth—and maybe even on Mars.

“The August solar eclipse gives us a rare opportunity to study the stratosphere when it’s even more Mars-like than usual,” said Jim Green, director of planetary science at NASA Headquarters in Washington. “With student teams flying balloon payloads from dozens of points along the path of totality, we’ll study effects on microorganisms that are coming along for the ride.”

NASA will provide each team with two small metal cards, each the size of a dog tag. The cards have harmless, yet environmentally resilient bacteria dried onto their surface. One card will fly up with the balloon while the other remains on the ground. A comparison of the two will show the consequences of the exposure to Mars-like conditions, such as bacterial survival and any genetic changes.

The results of the experiment will improve NASA’s understanding of environmental limits for terrestrial life, in order to inform our search for life on other worlds.

Mars’ atmosphere at the surface is about 100 times thinner than Earth’s, with cooler temperatures and more radiation. Under normal conditions, the upper portion of our stratosphere is similar to these Martian conditions, with its cold, thin atmosphere and exposure to radiation, due to its location above most of Earth’s protective ozone layer. Temperatures where the balloons fly can reach minus 35 degrees Fahrenheit (about minus 37 Celsius) or colder, with pressures about a hundredth of that at sea level.

During the eclipse, the similarities to Mars only increase. The Moon will buffer the full blast of radiation and heat from the Sun, blocking certain ultraviolet rays that are less abundant in the Martian atmosphere and bringing the temperature down even further.

“Performing a coordinated balloon microbiology experiment across the entire continental United States seems impossible under normal circumstances,” said David J. Smith of Ames, principal investigator for the experiment and mentor for the Space Life Science Training Program, the intern group developing flight hardware and logistics for this study. “The solar eclipse on August 21st is enabling unprecedented exploration through citizen scientists and students. After this experiment flies, we will have about 10 times more samples to analyze than all previously flown stratosphere microbiology missions combined.”

Student Teams Observing the Eclipse

Beyond the opportunity for NASA to conduct science, this joint project provides the opportunity for students as young as 10 years old to be exposed to the scientific method and astrobiology—research about life beyond Earth. Since ballooning is such an accessible and low-cost technique, the project has attracted student teams from Puerto Rico to Alaska.

The data collected by the teams will be analyzed by NASA scientists at Ames and NASA’s Jet Propulsion Laboratory, Pasadena, California; collaborators at Cornell University, Ithaca, New York; scientists funded by the National Science Foundation and National Oceanographic and Atmospheric Administration; faculty members and students at the teams’ institutions, as well as the public.

“This project will not only provide insight into how bacterial life responds to Mars-like conditions, we are engaging and inspiring the next generation of scientists,” said Green. “Through this exciting ‘piggyback’ mission, NASA is collaborating with scientists of the future to take a small step in the search for life beyond our planet.”

Using The Universe As A ‘Cosmological Collider’

Physicists are capitalizing on a direct connection between the largest cosmic structures and the smallest known objects to use the universe as a “cosmological collider” and investigate new physics.

The three-dimensional map of galaxies throughout the cosmos and the leftover radiation from the Big Bang – called the cosmic microwave background (CMB) – are the largest structures in the universe that astrophysicists observe using telescopes. Subatomic elementary particles, on the other hand, are the smallest known objects in the universe that particle physicists study using particle colliders.

A team including Xingang Chen of the Harvard-Smithsonian Center for Astrophysics (CfA), Yi Wang from the Hong Kong University of Science and Technology (HKUST) and Zhong-Zhi Xianyu from the Center for Mathematical Sciences and Applications at Harvard University has used these extremes of size to probe fundamental physics in an innovative way. They have shown how the properties of the elementary particles in the Standard Model of particle physics may be inferred by studying the largest cosmic structures. This connection is made through a process called cosmic inflation.

Cosmic inflation is the most widely accepted theoretical scenario to explain what preceded the Big Bang. This theory predicts that the size of the universe expanded at an extraordinary and accelerating rate in the first fleeting fraction of a second after the universe was created. It was a highly energetic event, during which all particles in the universe were created and interacted with each other. This is similar to the environment physicists try to create in ground-based colliders, with the exception that its energy can be 10 billion times larger than any colliders that humans can build.

Inflation was followed by the Big Bang, where the cosmos continued to expand for more than 13 billion years, but the expansion rate slowed down with time. Microscopic structures created in these energetic events got stretched across the universe, resulting in regions that were slightly denser or less dense than surrounding areas in the otherwise very homogeneous early universe. As the universe evolved, the denser regions attracted more and more matter due to gravity. Eventually, the initial microscopic structures seeded the large-scale structure of our universe, and determined the locations of galaxies throughout the cosmos.

In ground-based colliders, physicists and engineers build instruments to read the results of the colliding events. The question is then how we should read the results of the cosmological collider.

“Several years ago, Yi Wang and I, Nima Arkani-Hamed and Juan Maldacena from the Institute of Advanced Study, and several other groups, discovered that the results of this cosmological collider are encoded in the statistics of the initial microscopic structures. As time passes, they become imprinted in the statistics of the spatial distribution of the universe’s contents, such as galaxies and the cosmic microwave background, that we observe today,” said Xingang Chen. “By studying the properties of these statistics we can learn more about the properties of elementary particles.”

As in ground-based colliders, before scientists explore new physics, it is crucial to understand the behavior of known fundamental particles in this cosmological collider, as described by the Standard Model of particle physics.

“The relative number of fundamental particles that have different masses – what we call the mass spectrum – in the Standard Model has a special pattern, which can be viewed as the fingerprint of the Standard Model,” explained Zhong-Zhi Xiangyu. “However, this fingerprint changes as the environment changes, and would have looked very different at the time of inflation from how it looks now.”

The team showed what the mass spectrum of the Standard Model would look like for different inflation models. They also showed how this mass spectrum is imprinted in the appearance of the large-scale structure of our universe. This study paves the way for the future discovery of new physics.

“The ongoing observations of the CMB and large-scale structure have achieved impressive precision from which valuable information about the initial microscopic structures can be extracted,” said Yi Wang. “In this cosmological collider, any observational signal that deviates from that expected for particles in the Standard Model would then be a sign of new physics.”

The current research is only a small step towards an exciting era when precision cosmology will show its full power.

“If we are lucky enough to observe these imprints, we would not only be able to study particle physics and fundamental principles in the early universe, but also better understand cosmic inflation itself. In this regard, there are still a whole universe of mysteries to be explored,” said Xianyu.

Black Hole Feeding Frenzy Breaks Records

A giant black hole ripped apart a nearby star and then continued to feed off its remains for close to a decade, according to research led by the University of New Hampshire. This black hole meal is more than 10 times longer than any other previous episode of a star’s death.

“We have witnessed a star’s spectacular and prolonged demise,” said Dacheng Lin, a research scientist at UNH’s Space Science Center and the study’s lead author. “Dozens of these so-called tidal disruption events have been detected since the 1990s, but none that remained bright for nearly as long as this one.”

Using data from a trio of orbiting X-ray telescopes, NASA’s Chandra X-ray Observatory and Swift Satellite as well as ESA’s XMM-Newton, researchers found evidence of a massive “tidal disruption event” (TDE). Tidal forces, due to the intense gravity from the black hole, can destroy an object — such as a star — that wanders too close. During a TDE, some of the stellar debris is flung outward at high speeds, while the rest falls toward the black hole. As it travels inward, and is ingested by the black hole, the material heats up to millions of degrees and generates a distinct X-ray flare.

These multiwavelength flares, which can be viewed by the satellites, help to study otherwise dormant massive back holes. Previous flares were short-lived, typically becoming very faint in a year, but this super-long X-ray flare has been persistently bright for close to a decade. The extraordinary long bright phase of this TDE means that either this was the most massive star ever to be torn apart during one of these events, or the first where a smaller star was completely torn apart.

The X-ray source containing this force-fed black hole, known by its abbreviated name of XJ1500+0154, is located in a small galaxy about 1.8 billion light years from Earth. The X-ray data also indicates that radiation from material surrounding this black hole has consistently surpassed the so-called Eddington limit, defined by a balance between the outward pressure of radiation from the hot gas and the inward pull of the gravity of the black hole.

The conclusion that supermassive black holes can grow, from TDEs and perhaps other means, at rates above those corresponding to the Eddington limit has important implications. Such rapid growth may help explain how supermassive black holes were able to reach masses about a billion times higher than the sun when the universe was only about a billion years old.

Based on the modeling by the researchers the black hole’s feeding supply should be significantly reduced in the next decade and begin to fade in the next several years.

BREAKING NEWS: NASA Mission Tries to Discern Comets From Asteroids

First, let me address the traditional explanation of the difference between comets and asteroids. Secondly, I will inform you of what traditional explanations omit – by accident or purposeful is for you to decide. My personal research has come to the following conclusion: In the most simple of terms: “An asteroid is nothing more than an outgassed comet…period.”

Traditional
The main difference between asteroids and comets is their composition, as in, what they are made of. Asteroids are made up of metals and rocky material, while comets are made up of ice, dust and rocky material. Both asteroids and comets were formed early in the history of the solar system about 4.5 billion years ago. Asteroids formed much closer to the Sun, where it was too warm for ices to remain solid. Comets formed farther from the Sun where ices would not melt.

New Thought
The hypothesis of the explosion of a number of planets and moons of our Solar System during its 4.6-billion-year history is in excellent accord with all known observational constraints, even without adjustable parameters or ad hoc helper hypotheses.

Many of its boldest predictions have been fulfilled. In most instances, these predictions were judged highly unlikely by the current standard models. Moreover, in several cases, the entire exploded planet model was at risk of being falsified if the predictions failed.

The successful predictions include: (1) satellites of asteroids; (2) satellites of comets; (3) salt water in meteorites; (4) ‘roll marks’ leading to boulders on asteroids; (5) the time and peak rate of the 1999 Leonid meteor storm; (6) explosion signatures for asteroids; (7) the strongly spiked energy parameter for new comets; (8) the distribution of black material on slowly rotating airless bodies; (9) splitting velocities of comets; (10) the asteroid-like nature of Deep Impact target Comet Tempel 1; and (11) the presence of high-formation-temperature minerals in the Stardust comet dust sample return.

By all existing evidence, the exploded planet hypothesis has proved far more useful than the half-dozen or so hypotheses it would replace. Among the many important conclusions are the following. (a) Perhaps as many as six former planets of our Solar System have exploded over its 4.6-billion-year history. (b) In particular, Mars is not an original planet, but a former moon of an exploded planet. (c) As a major player in Solar System evolution, the exploded planet scenario must be considered as a likely propagation vehicle for the spread of biogenic organisms.

NASA’s NEOWISE mission has recently discovered some celestial objects traveling through our neighborhood, including one on the blurry line between asteroid and comet. Another asteroid/comet might be seen with binoculars through next week.

An object called 2016 WF9 was detected by the NEOWISE project on Nov. 27, 2016. It is in an orbit that takes it on a scenic tour of our solar system. At its farthest distance from the Sun, it approaches Jupiter’s orbit. Over the course of 4.9 Earth-years, it travels inward, passing under the main asteroid belt and the orbit of Mars until it swings just inside Earth’s own orbit. After that, it heads back toward the outer solar system. Objects in these types of orbits have multiple possible origins; it might once have been a comet, or it could have strayed from a population of dark objects in the main asteroid belt.

2016 WF9 will approach Earth’s orbit on Feb. 25, 2017. At a distance of nearly 32 million miles (51 million kilometers) from Earth, this pass will not bring it particularly close. The trajectory of 2016 WF9 is well understood, and the object is not a threat to Earth for the foreseeable future.

A different object, discovered by NEOWISE a month earlier, is more clearly a comet, releasing dust as it nears the Sun. This comet, C/2016 U1 NEOWISE, “has a good chance of becoming visible through a good pair of binoculars, although we can’t be sure because a comet’s brightness is notoriously unpredictable,” said Paul Chodas, manager of NASA’s Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California.

As seen from the northern hemisphere during the first week of 2017, comet C/2016 U1 NEOWISE will be in the southeastern sky shortly before dawn. It is moving farther south each day and it will reach its closest point to the Sun, inside the orbit of Mercury, on Jan. 14, before heading back out to the outer reaches of the solar system for an orbit lasting thousands of years. While it will be visible to skywatchers at Earth, it is not considered a threat to our planet either.

NEOWISE is the asteroid-and-comet-hunting portion of the Wide-Field Infrared Survey Explorer (WISE) mission. After discovering more than 34,000 asteroids during its original mission, NEOWISE was brought out of hibernation in December of 2013 to find and learn more about asteroids and comets that could pose an impact hazard to Earth. If 2016 WF9 turns out to be a comet, it would be the 10th discovered since reactivation. If it turns out to be an asteroid, it would be the 100th discovered since reactivation.

What NEOWISE scientists do know is that 2016 WF9 is relatively large: roughly 0.3 to 0.6 mile (0.5 to 1 kilometer) across. It is also rather dark, reflecting only a few percent of the light that falls on its surface. This body resembles a comet in its reflectivity and orbit, but appears to lack the characteristic dust and gas cloud that defines a comet.

“2016 WF9 could have cometary origins,” said Deputy Principal Investigator James “Gerbs” Bauer at JPL. “This object illustrates that the boundary between asteroids and comets is a blurry one; perhaps over time this object has lost the majority of the volatiles that linger on or just under its surface.”

Near-Earth objects (NEOs) absorb most of the light that falls on them and re-emit that energy at infrared wavelengths. This enables NEOWISE’s infrared detectors to study both dark and light-colored NEOs with nearly equal clarity and sensitivity.

“These are quite dark objects,” said NEOWISE team member Joseph Masiero, “Think of new asphalt on streets; these objects would look like charcoal, or in some cases are even darker than that.

NEOWISE data have been used to measure the size of each near-Earth object it observes. Thirty-one asteroids that NEOWISE has discovered pass within about 20 lunar distances from Earth’s orbit, and 19 are more than 460 feet (140 meters) in size but reflect less than 10 percent of the Sunlight that falls on them.

The Wide-field Infrared Survey Explorer (WISE) has completed its seventh year in space after being launched on Dec. 14, 2009.

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As a result of natural disasters occurring more often (no surprise for us paying attention), I find myself engaged in the onsite events more often, and less available to maintain my alternative ventures keeping SOC healthy. But thanks to my wife’s exorbitant creative thinking, I believe we found a way to stay on top.

Between now and January 15th 2017, by donating $10 you will be grandfathered into a full one year membership. Beginning January 1st 2017, we will be going back to our annual memberships starting at $34.95 per year. Yes, this is to say with just $10 you will have a full membership for the next full year of 2017.

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Go to the following link which takes you to a page. On the right side of our home page under where it says “Science of Cycles Community Support” you will find a drop-down menu to choose your amount. Beginning next year we will have other methods for you to purchase a membership, for now please use PayPal. Remember, you do not have to join PayPal to use it. Just look for the tap that says Pay with Debit or Credit Card. No sign-up is necessary.……..CLICK HERE

Comet Lovejoy Shows Asymmetric Behavior At Perihelion

Indian astronomers have recently conducted spectrographic observations of long-period Comet Lovejoy to study its gas emission. They found that this comet showcases an asymmetric behavior at perihelion and an increase in the activity during the post-perihelion phase. The findings were detailed in a paper published July 22 on the arXiv pre-print server.

cometlovejoy

Comet Lovejoy, formally designated C/2014 Q2, is an Oort cloud comet, discovered by Terry Lovejoy in August 2014. Its perihelion was on January 30, 2015 at a heliocentric distance of 1.29 AU, offering astronomers an excellent opportunity to observe its activity—in particular, the emission of numerous organic molecules in gas.

The scientists, led by Kumar Venkataramani of the Physical Research Laboratory in Ahmedabad, India, utilized the LISA spectrograph to obtain spectra of the comet. LISA is a low-resolution, high luminosity spectrograph, designed for the spectroscopic study of faint and extended objects. The instrument is installed on the 0.5 m telescope at the Mount Abu Infra-Red Observatory (MIRO), Mount Abu, India.

The observation campaign lasted from January to May 2015. It covered the period during which the comet’s heliocentric distance varied from 1.29 AU, just prior to perihelion, to around 2.05 AU post perihelion. The spectra obtained by the researchers show strong molecular emission bands of diatomic carbon, tricarbon, cyanide, amidogen, hydridocarbon and neutral oxygen.

“Various molecular emission lines like C2, C3, CN, NH2, CH, O were clearly seen in the comet spectrum throughout this range. The most prominent of them being the C2 molecule, which was quite dominant throughout the time that we have followed the comet. Apart from the C2 emission band, those of CN and C3 were also quite prominent,” the scientist wrote in the paper.

When a cold icy body like the Comet Lovejoy passes by the sun near perihelion, its ices start sublimating, releasing a mixture of gas and dust, which form the coma. Studying these emissions is crucial for scientists as comets could hold the key to our understanding of the solar system’s evolution and the origin of life in the universe. Therefore, the abundance of volatile material in comets is the target of many scientific studies that seek to reveal the secrets of planet formation and demonstrate the conditions that occurred when our solar system was born.

According to the study, the gas production rate increased after perihelion and exhibited a decreasing trend only after February 2015. The researchers also noted a simultaneous increase in gas and dust, indicating an increase in the overall activity of the comet after its perihelion passage.

“This kind of asymmetry has been seen in many comets. (…) Although we do not have data points at exactly the same distance for pre- and post-perihelion passages, we can, perhaps, say that this comet may have a large positive asymmetry,” the paper reads.

The scientists concluded that this asymmetry suggests that there might be volatile material present beneath the surface of the comet. It is also possible that the surface of the comet’s nucleus consists of layers of ice that have different vaporization rates.

However, as the team noted, more exhaustive study is required to confirm their conclusions.