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Galactic Collision at 2 Million mph Offers Glimpse Into Earth’s Potential Fate

mahla — Sat, 23 Nov 2024 23:41:06 +0000

TEHRAN (Iran News) An international team of scientists has observed a dramatic collision between two galaxies 290 million light-years away, offering a glimpse into the dynamics of such cataclysmic events.

The collision involved galaxy NGC 7318b barreling toward another at a staggering 2 million mph (3.2 million km/h), driven by immense gravitational forces.

“This high-speed collision is causing havoc in NGC 7318b, particularly with respect to its reserves of hydrogen gas, which are being stripped off,” researchers noted.

Hydrogen, crucial for star formation, is being disrupted, likely slowing the galaxy’s ability to generate new stars.

The event was detected using cutting-edge equipment, including the £16.7 million William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE) in Spain and the Low-Frequency Array (LOFAR) radio telescope in the Netherlands.

The collision unfolded within Stephan’s Quintet, a group of five galaxies: NGC 7317, NGC 7318a, NGC 7318b, NGC 7319, and NGC 7320.

“NGC 7318b is coming into the galaxy group from behind and colliding with NGC 7318a,” explained Professor Gavin Dalton of the University of Oxford, who leads the WEAVE project.

The light from this cosmic crash has traveled 285 million years to reach Earth, meaning astronomers are observing events from that period.

The violent encounter, which likely lasted about 10,000 years, released immense energy, creating a powerful shockwave similar to a sonic boom.

“The shock is powerful enough to rip electrons from atoms, leaving a glowing trail of charged gas,” said lead researcher Dr. Marina Arnaudova of the University of Hertfordshire.

However, when the shockwave moves through surrounding hot gas, it weakens, compressing the gas and emitting radio waves detectable by telescopes like LOFAR.

The findings, published in the Monthly Notices of the Royal Astronomical Society, provide a preview of what might happen if the Milky Way collides with the Andromeda galaxy in about 10 billion years.

While astronomers estimate a 50% chance of such a collision, the event would likely reshape both galaxies into a new superstructure dubbed “Milkdromeda.”

Planets and stars could be flung into new orbits, with a small possibility of Earth facing catastrophic changes.

“Even a close pass with another star could alter Earth’s orbit, which might lead to freezing or intense heating,” said Eric Bell, professor of astronomy at the University of Michigan.

Despite these theoretical risks, astronomers emphasize that Earth’s greater threats lie in the sun’s evolution, which will destabilize long before any galactic collision.

The WEAVE project, funded by the UK’s Science and Technology Facilities Council and contributions from other European nations, has opened new frontiers in mapping the universe.

“The details of this collision and the insights from Stephan’s Quintet are just a taste of what’s to come,” said Professor Dalton.

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In Travelling Earth, Mars, Bacteria Survives

reporter 1222 — Thu, 27 Aug 2020 05:25:12 +0000

TEHRAN (Iran News) – Tanpopo mission addresses the possibility of natural interplanetary transport of microbial life called panspermia.

Imagine microscopic life-forms, such as bacteria, transported through space, and landing on another planet. The bacteria finding suitable conditions for its survival could then start multiplying again, sparking life at the other side of the universe.

This theory, called “panspermia”, support the possibility that microbes may migrate between planets and distribute life in the universe. Long controversial, this theory implies that bacteria would survive the long journey in outer space, resisting to space vacuum, temperature fluctuations, and space radiations, eurekalert.org reported.

“The origin of life on Earth is the biggest mystery of human beings. Scientists can have totally different points of view on the matter. Some think that life is very rare and happened only once in the Universe, while others think that life can happen on every suitable planet. If panspermia is possible, life must exist much more often than we previously thought,” says Dr. Akihiko Yamagishi, a Professor at Tokyo University of Pharmacy and Life Sciences and principal investigator of the space mission Tanpopo.

In 2018, Dr. Yamagishi and his team tested the presence of microbes in the atmosphere. Using an aircraft and scientific balloons, the researchers, found Deinococcal bacteria floating 12 km above the earth. But while Deinococcus are known to form large colonies (easily larger than one millimeter) and be resistant to environmental hazards like UV radiation, could they resist long enough in space to support the possibility of panspermia?

To answer this question, Dr. Yamagishi and the Tanpopo team, tested the survival of the radioresistant bacteria Deinococcus in space. The study, now published in Frontiers in Microbiology, shows that thick aggregates can provide sufficient protection for the survival of bacteria during several years in the harsh space environment.

Dr. Yamagishi and his team came to this conclusion by placing dried Deinococcus aggregates in exposure panels outside of the International Space Station (ISS). The samples of different thicknesses were exposed to space environment for one, two, or three years and then tested for their survival.

After three years, the researchers found that all aggregates superior to 0.5 mm partially survived to space conditions. Observations suggest that while the bacteria at the surface of the aggregate died, it created a protective layer for the bacteria beneath ensuring the survival of the colony. Using the survival data at one, two, and three years of exposure, the researchers estimated that a pellet thicker than 0.5 mm would have survived between 15 and 45 years on the ISS. The design of the experiment allowed the researcher to extrapolate and predict that a colony of 1 mm of diameter could potentially survive up to 8 years in outer space conditions.

“The results suggest that radioresistant Deinococcus could survive during the travel from Earth to Mars and vice versa, which is several months or years in the shortest orbit,” says Dr. Yamagishi.

This work provides, to date, the best estimate of bacterial survival in space. And, while previous experiments prove that bacteria could survive in space for a long period when benefitting from the shielding of rock (i.e. lithopanspermia), this is the first long-term space study raising the possibility that bacteria could survive in space in the form of aggregates, raising the new concept of “massapanspermia”. Yet, while we are one step closer to prove panspermia possible, the microbe transfer also depends on other processes such as ejection and landing, during which the survival of bacteria still needs to be assessed.

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‘Ring of Fire’ Seen on Venus

reporter 1222 — Thu, 23 Jul 2020 12:58:42 +0000

TEHRAN (Iran News) – ETH researchers used computer simulations to classify the current activity of corona structures on the surface of Venus. To their surprise, they found a previously undiscovered ring of fire on our neighboring planet.

Years ago, planetary researchers discovered unusual circular structures on the surface of Venus when observing high-resolution images from NASA’s Magellan mission. Such structures are known as coronae (from the Latin meaning “crowns”; singular: corona). A few years ago, a team of ETH researchers led by Taras Gerya, Professor of Geophysics at the Department of Earth Sciences, used computer models to investigate how these structures may have formed.

Most researchers assume that these odd circular surface features are formed by mantle plumes from deep within the planet.

A mantle plume is an upwelling of hot, molten rock that is transported by convection currents from the lower mantle to the crust in a column that widens in a mushroom-shape at the top. The heat it carries melts the surface of the crust in a circular form. Continuous material rising from greater depths widens the plume head and expands the ring structure on the surface to form a corona. The solid crust surrounding the mantle plume may crack and ultimately sink below the edge of the corona, triggering local tectonic processes.

Computer simulations of structural variations of coronae

However, the topography of coronae is by no means homogeneous or easy to describe. “These structures exist in a large variety of shapes and dimensions on the Venusian surface,” says Anna Gülcher, a doctoral student in Gerya’s research group.

Following up on this observation, Gülcher used a larger set of improved 3D simulations to re-examine the coronae as she sought to establish a link between the variation in surface topography and the processes at work beneath. Her study was recently published in the journal Nature Geoscience.

The new simulations show that a corona’s topography depends on the thickness and strength of the crust where the mantle plume strikes it and, above all, that their topographies are directly related to how active the column of magma beneath the surface is.

It is important to note, however, that the position and dynamics of Earth’s ring of fire are the result of plate tectonics, she explains. On Venus, the cause is vertical hotspot volcanism—a phenomenon that occurs in only a few places on Earth, such as below the Hawaiian Islands.

Exactly why the mantle plumes on Venus are arranged in such a belt, and what this means for deep interior processes on Venus, is an important question to address in future studies, Gülcher says. This may be done with large-scale computer simulations.

Huge computing capacity required

In their models, the researchers simulate only the very top few hundred kilometers of the mantle plume. In reality, however, the plume conduits could be over 1,000 kilometers long: “Simulating the total length the plumes could reach is out of the question because of the huge computing capacity it would require,” Gülcher says. The current simulations, performed using the Euler cluster at ETH, are already eight times larger than previous ones.

The planetary scientists hope that their findings will also provide fresh insights into how mantle plumes function below the surface of the Earth. They are likely to be what causes hotspot volcanism, as seen in the Hawaiian Islands. Mantle plumes may have been a trigger for plate tectonics observed on Earth as well, as Gerya’s research group was also able to simulate. As mentioned at the time, Venus could serve as a model for the processes that may have taken place in Earth’s early history.

Active plumes from a ring of fire around Venus

This salient observation enabled Gülcher and her colleagues to classify over a hundred of large coronae on Venus into two main groups: those that have formed above an active plume that is currently rising and carrying molten material, and those above a plume that has cooled and become inactive. “Every corona structure has a specific signature that indicates what is going on beneath it,” Gülcher says.

On a map of Venus, she plotted all the coronae according to how their activity was classified. To her surprise, most of the coronae overlying active mantle plumes form a belt in Venus’ southern hemisphere. Only a handful of active plumes are located outside this band. “We called this band the ‘Ring of Fire’ on Venus in reference to the ‘Ring of Fire’ on Earth,” Gülcher says. She assumes that the belt coincides with a zone that expels high levels of rising plume material.

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1.5-Degree Warming Threshold Is Close

reporter 1222 — Thu, 09 Jul 2020 13:01:22 +0000

TEHRAN (Iran News) – The world could see average global temperatures 1.5 degrees Celsius (2.7 Fahrenheit) above the pre-industrial average for the first time in the coming five years, the UN weather agency said Thursday.

The 1.5-C mark is the level to which countries have agreed to try to limit global warming. Scientists say average temperatures around the world are already at least 1 C higher now than during the period from 1850-1900 because of man-made greenhouse emissions.

The World Meteorological Organization said there is a 20 percent chance that the 1.5 C level will be reached in at least one year between 2020 and 2024. The period is expected to see annual average temperatures that are 0.91 C to 1.59 C higher than pre-industrial averages.

The forecast is contained in an annual climate outlook, spearheaded by the United Kingdom’s Met Office.

WMO chief Petteri Taalas said the study shows “the enormous challenge” countries face in meeting the goals of the 2015 Paris accord. The agreement sets a goal of keeping global warming well below 2 degrees Celsius, ideally no more than 1.5 C.

The agency noted that the models used for the forecast don’t consider the impact that the coronavirus pandemic might have on reducing emissions of planet-warming gases such as carbon dioxide.

“The industrial and economic slowdown from COVID-19 is not a substitute for sustained and coordinated climate action,” Taalas said, AP reported.

“Due to the very long lifetime of CO2 in the atmosphere, the impact of the drop in emissions this year is not expected to lead to a reduction of CO2 atmospheric concentrations which are driving global temperature increases,” he said.

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South Pole Warming Three Times Faster than Rest of Earth

reporter 1222 — Tue, 30 Jun 2020 13:05:38 +0000

TEHRAN (Iran News) – The South Pole has been warming three times faster than the rest of the planet in the last 30 years due to warmer tropical ocean temperatures, new research showed Monday.

Antarctica’s temperature varies widely according to season and region, and for years it had been thought that the South Pole had stayed cool even as the continent heated up.

Researchers in New Zealand, Britain and the United States analyzed 60 years of weather station data and used computer modeling to show what was causing the accelerated warming, Phys.org reported.

They found that warmer ocean temperatures in the western Pacific had over the decades lowered atmospheric pressure over the Weddell Sea in the southern Atlantic.

This in turn had increased the flow of warm air directly over the South Pole—warming it by more than 1.83C (about 3.3F) since 1989.

Authors of the research said the natural warming trend was likely boosted by manmade greenhouse gas emissions and could be masking the heating effect of carbon pollution over the South Pole.

“While temperatures were known to be warming across West Antarctica and the Antarctic Peninsula during the 20th century, the South Pole was cooling,” said Kyle Clem, a researcher at Victoria University of Wellington, and lead study author.

“It was suspected that this part of Antarctica… might be immune to/isolated from warming. We found this is not the case any more,” he told AFP.

The data showed that the South Pole—the most remote spot on Earth—was now warming at a rate of around 0.6C (1.1F) a decade, compared with around 0.2C (1.4F) for the rest of the planet.

The authors of the study, published in the Nature Climate Change journal, attributed the change to a phenomenon known as the Interdecadal Pacific Oscillation (IPO).

The IPO cycle lasts roughly 15-30 years, and alternates between a “positive” state—in which the tropical Pacific is hotter and the northern Pacific is colder than average—and a “negative” state where the temperature anomaly is reversed.

The IPO flipped to a negative cycle at the start of the century, driving greater convection and more pressure extremes at high latitudes, leading to a strong flow of warmer air right over the South Pole.

Clem said that the 1.83C (3.3F) level of warming exceeded 99.99 percent of all modeled 30-year warming trends.

“While the warming was just within the natural variability of climate models, it was highly likely human activity had contributed,” he said.

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Giant Asteroid Approaching Earth’s Orbit

reporter 1222 — Mon, 18 May 2020 12:37:16 +0000

TEHRAN (Iran News) – NASA’s Center for Near-Earth Object Studies is tracking a giant asteroid that will approach Earth’s orbit on May 21.

The asteroid measures between 670 metres and 1.5 kilometres in diameter, the equivalent to 2198ft and 4921ft wide, the Daily Star reported.

NASA has dubbed the rock 136796 (1997 BQ), and it was first observed by astrologists on January 16, 1997.

It is classed as an Apollo asteroid, one which intersects with Earth’s orbit during its space journey.

The asteroid is expected to approach Earth’s orbit on Thursday, May 21st at 9.45 PM Eastern Time, or 02.45 am on Friday, May 22nd British Standard Time.

NASA estimates the asteroid is travelling at 11.68 kilometres a second or 26,127 miles per hour.

It is registered as a Near-Earth object as it is expected to come within 1.3 astronomical units – 150 million kilometres (93 million miles) – between Earth and the Sun.

A Near-Earth object is any small Solar System body, including comets, whose orbit brings it to proximity with Earth.

NASA’s National Near-Earth Object Preparedness Strategy and Action Plan has previously warned asteroids up to 1km in diameter can initiative a chain of devastating events.

NASA’s report states: “Objects close to and larger than one kilometre can cause damage on a global scale.

“They can trigger earthquakes, tsunamis, and other secondary effects that extend far beyond the immediate impact area.

“An asteroid as large as 10 kilometres across is thought to have caused the extinction of the dinosaurs when it struck the Yucatan peninsula some 65 million years ago.”

Astronomers are currently tracking nearly 2,000 asteroids, comets and other objects that threaten our planet.

According to Nasa, a NEO is a term used to describe “comets and asteroids that have been nudged by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth’s neighbourhood”.

Earth hasn’t seen an asteroid of apocalyptic scale since the space rock that wiped out the dinosaurs 66million years ago.

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Astronomers Discover Closest Black Hole to Earth

reporter 1222 — Thu, 07 May 2020 15:21:04 +0000

Astronomers Discover Closest Black Hole to Earth

According To Iran News, European astronomers have found the closest black hole to Earth yet, so near that the two stars dancing with it can be seen by the naked eye.

Of course, close is relative on the galactic scale. This black hole is about 1,000 light-years away and each light-year is 5.9 trillion miles (9.5 trillion kilometers). But in terms of the cosmos and even the galaxy, it is in our neighborhood, said European Southern Observatory astronomer Thomas Rivinius, who led the study published Wednesday in the journal Astronomy & Astrophysics.

The previous closest black hole is probably about three times further, about 3,200 light-years, he said.

The discovery of a closer black hole, which is in the constellation Telescopium in the Southern Hemisphere, hints that there are more of these out there. Astronomers theorize there are between 100 million to 1 billion of these small but dense objects in the Milky Way.

The trouble is we can’t see them. Nothing, not even light, escapes a black hole’s gravity. Usually, scientists can only spot them when they’re gobbling up sections of a partner star or something else falling into them. Astronomers think most black holes, including this newly discovered one, don’t have anything close enough to swallow. So they go undetected.

Astronomers found this one because of the unusual orbit of a star. The new black hole is part of what used to be a three-star dance in a system called HR6819. The two remaining super-hot stars aren’t close enough to be sucked in, but the inner star’s orbit is warped.

Using a telescope in Chile, they confirmed that there was something about four or five times the mass of our sun pulling on the inner star. It could only be a black hole, they concluded.

Outside astronomers said that makes sense.

“It will motivate additional searches among bright, relatively nearby stars,” said Ohio State University astronomer Todd Thompson, who wasn’t part of the research.

Like most of these type of black holes this one is tiny, maybe 25 miles (40 kilometers) in diameter.

“Washington, DC, would quite easily fit into the black hole, and once it went in it, would never come back,” said astronomer Dietrich Baade, a study co-author.

These are young hot stars compared to our 4.6 billion-year-old sun. They’re maybe 140 million years old, but at 26,000 degrees F (15,000 degrees C) they are three times hotter than the sun, Rivinius said. About 15 million years ago, one of those stars got too big and too hot and went supernova, turning into the black hole in a violent process, he said.

“It is most likely that there are black holes much closer than this one,” said Avi Loeb, director of Harvard’s Black Hole Initiative, who wasn’t part of the study. “If you find an ant while scanning a tiny fraction of your kitchen, you know there must be many more out there.”

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Potentially Habitable Large Exoplanet Found

reporter 1222 — Thu, 27 Feb 2020 15:09:25 +0000

Potentially Habitable Large Exoplanet Found

According To Iran News, Astronomers have found an exoplanet more than twice the size of Earth to be potentially habitable, opening the search for life to planets significantly larger than Earth but smaller than Neptune.

A team from the University of Cambridge used the mass, radius, and atmospheric data of the exoplanet K2-18b and determined that it’s possible for the planet to host liquid water at habitable conditions beneath its hydrogen-rich atmosphere. The results are reported in The Astrophysical Journal Letters.

The exoplanet K2-18b, 124 light-years away, is 2.6 times the radius and 8.6 times the mass of Earth, and orbits its star within the habitable zone, where temperatures could allow liquid water to exist. The planet was the subject of significant media coverage in the autumn of 2019, as two different teams reported detection of water vapour in its hydrogen-rich atmosphere. However, the extent of the atmosphere and the conditions of the interior underneath remained unknown.

“Water vapor has been detected in the atmospheres of a number of exoplanets but, even if the planet is in the habitable zone, that doesn’t necessarily mean there are habitable conditions on the surface,” said Dr. Nikku Madhusudhan from Cambridge’s Institute of Astronomy, who led the new research, Phys.org reported. “To establish the prospects for habitability, it is important to obtain a unified understanding of the interior and atmospheric conditions on the planet—in particular, whether liquid water can exist beneath the atmosphere.”

Given the large size of K2-18b, it has been suggested that it would be more like a smaller version of Neptune than a larger version of Earth. A ‘mini-Neptune’ is expected to have a significant hydrogen ‘envelope’ surrounding a layer of high-pressure water, with an inner core of rock and iron. If the hydrogen envelope is too thick, the temperature and pressure at the surface of the water layer beneath would be far too great to support life.

Now, Madhusudhan and his team have shown that despite the size of K2-18b, its hydrogen envelope is not necessarily too thick and the water layer could have the right conditions to support life. They used the existing observations of the atmosphere, as well as the mass and radius, to determine the composition and structure of both the atmosphere and interior using detailed numerical models and statistical methods to explain the data.

The researchers confirmed the atmosphere to be hydrogen-rich with a significant amount of water vapour. They also found that levels of other chemicals such as methane and ammonia were lower than expected for such an atmosphere. Whether these levels can be attributed to biological processes remains to be seen.

The team then used the atmospheric properties as boundary conditions for models of the planetary interior. They explored a wide range of models that could explain the atmospheric properties as well as the mass and radius of the planet. This allowed them to obtain the range of possible conditions in the interior, including the extent of the hydrogen envelope and the temperatures and pressures in the water layer.

“We wanted to know the thickness of the hydrogen envelope—how deep the hydrogen goes,” said co-author Matthew Nixon, a Ph.D. student at the Institute of Astronomy. “While this is a question with multiple solutions, we’ve shown that you don’t need much hydrogen to explain all the observations together.”

The researchers found that the maximum extent of the hydrogen envelope allowed by the data is around 6% of the planet’s mass, though most of the solutions require much less. The minimum amount of hydrogen is about one-millionth by mass, similar to the mass fraction of the Earth’s atmosphere. In particular, a number of scenarios allow for an ocean world, with liquid water below the atmosphere at pressures and temperatures similar to those found in Earth’s oceans.

This study opens the search for habitable conditions and bio-signatures outside the solar system to exoplanets that are significantly larger than Earth, beyond Earth-like exoplanets. Additionally, planets such as K2-18b are more accessible to atmospheric observations with current and future observational facilities. The atmospheric constraints obtained in this study can be refined using future observations with large facilities such as the upcoming James Webb Space Telescope.

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There Be No Microbe!

reporter 1222 — Mon, 25 Nov 2019 08:30:27 +0000

Researcher found a place with no microbe living there.

What makes the Earth habitable? Is it possible with no microbe?

It has the right chemical ingredients for life, including water and carbon. But European scientists have recently discovered a place on Earth where no one can live because there is no microbe living.

Scientists have confirmed the absence of microbial life in hot, saline, hyperacid ponds in the Dallol geothermal field in Ethiopia, Iran News quotes what TechExplorist reported.

According to a study, certain microorganisms can develop in such multi-extreme environment. The study led authors to present this place as an example of the limits that life can support, and even to propose it as a terrestrial analogue of early Mars.

But a new study by the French-Spanish team of scientists led by biologist Purificación Lopez Garcia of the French National Centre for Scientific Research (CNRS) suggests that there is no life in Dallol’s multi-extreme ponds.

Lopez Garcia said, “After analyzing many more samples than in previous works, with adequate controls so as not to contaminate them and a well-calibrated methodology, we have verified that there’s no microbial life in these salty, hot and hyperacid pools or in the adjacent magnesium-rich brine lakes.”

“What does exist is a great diversity of halophilic archaea (a type of primitive salt-loving microorganism) in the desert and the saline canyons around the hydrothermal site, but neither is found in the hyperacid and hypersaline pools themselves, nor in the so-called Black and Yellow lakes of Dallol, where magnesium abounds. And all this despite the fact that microbial dispersion in this area, due to the wind and to human visitors, is intense.”

The results of the study were confirmed by using different methods like the massive sequencing of genetic markers to detect and classify microorganisms, microbial culture attempts, fluorescent flow cytometry to identify individual cells, chemical analysis of brines and scanning electron microscopy combined with X-ray spectroscopy.

López García cautioned, “some silica-rich Dallol mineral precipitates may look like microbial cells under a microscope, so what is seen must be analyzed well. In other studies, apart from the possible contamination of samples with archaea from adjacent lands, these mineral particles may have been interpreted as fossilized cells, when in reality they form spontaneously in the brines even though there is no life.”

Scientists particularly discovered two physical-chemical barriers that prevent the presence of living organisms in ponds: the abundance of chaotropic magnesium salts (an agent that breaks hydrogen bridges and denatures biomolecules) and the simultaneous confluence of hypersaline, hyperacid and high-temperature conditions.

The study helps to circumscribe the limits of habitability and demands caution when interpreting morphological biosignatures on Earth and beyond. Meanwhile, one should not rely on the apparently cellular or “biological” aspect of a structure, because it could have an abiotic origin.

The study also presented an evidence that there are places on the Earth’s surface, such as the Dallol pools, which are sterile even though they contain liquid water. Meanwhile, the presence of liquid water on a planet, which is often used as a habitability criterion, doesn’t necessarily means that it has life.

Lopez Garcia said, “We would not expect to find life forms in similar environments on other planets, at least not based on a biochemistry similar to terrestrial biochemistry.”

Scientists are continuing to investigate the extreme environment of Dallol.

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Researchers Cooking Up Alien Atmosphere Here on Earth

reporter 1222 — Sat, 16 Mar 2019 08:30:33 +0000

Researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, are cooking up an alien atmosphere right here on Earth.

In a new study, JPL scientists used a high-temperature “oven” to heat a mixture of hydrogen and carbon monoxide to more than 2,000 degrees Fahrenheit (1,100 Celsius), about the temperature of molten lava. The aim was to simulate conditions that might be found in the atmospheres of a special class of exoplanets (planets outside our solar system) called “hot Jupiters.”

Hot Jupiters are gas giants that orbit very close to their parent star, unlike any of the planets in our solar system. While Earth takes 365 days to orbit the Sun, hot Jupiters orbit their stars in less than 10 days. Their close proximity to a star means their temperatures can range from 1,000 to 5,000 degrees Fahrenheit (530 to 2,800 degrees Celsius) or even hotter. By comparison, a hot day on the surface of Mercury (which takes 88 days to orbit the Sun) reaches about 800 degrees Fahrenheit (430 degrees Celsius).

“Though it is impossible to exactly simulate in the laboratory these harsh exoplanet environments, we can come very close,” said JPL principal scientist Murthy Gudipati, who leads the group that conducted the new study, published last month in the Astrophysical Journal.

The team started with a simple chemical mixture of mostly hydrogen gas and 0.3 percent carbon monoxide gas. These molecules are extremely common in the universe and in early solar systems, and they could reasonably compose the atmosphere of a hot Jupiter. Then the team heated the mixture to between 620 and 2,240 degrees Fahrenheit (330 and 1,230 Celsius).

The team also exposed the laboratory brew to a high dose of ultraviolet radiation – similar to what a hot Jupiter would experience orbiting so close to its parent star. The UV light proved to be a potent ingredient. It was largely responsible for some of the study’s more surprising results about the chemistry that might be taking place in these toasty atmospheres.

Hot Jupiters are large by planet standards, and they radiate more light than cooler planets. Such factors have allowed astronomers to gather more information about their atmospheres than most other types of exoplanets. Those observations reveal that many hot Jupiter atmospheres are opaque at high altitudes. Although clouds might explain the opacity, they become less and less sustainable as the pressure decreases, and the opacity has been observed where the atmospheric pressure is very low.

Scientists have been looking for potential explanations other than clouds, and aerosols – solid particles suspended in the atmosphere – could be one. However, according to the JPL researchers, scientists were previously unaware of how aerosols might develop in hot Jupiter atmospheres. In the new experiment, adding UV light to the hot chemical mix did the trick.

“This result changes the way we interpret those hazy hot Jupiter atmospheres,” said Benjamin Fleury, a JPL research scientist and lead author of the study. “Going forward, we want to study the properties of these aerosols. We want to better understand how they form, how they absorb light and how they respond to changes in the environment. All that information can help astronomers understand what they’re seeing when they observe these planets.”

The study yielded another surprise: The chemical reactions produced significant amounts of carbon dioxide and water. While water vapor has been found in hot Jupiter atmospheres, scientists for the most part expect this precious molecule to form only when there is more oxygen than carbon. The new study shows that water can form when carbon and oxygen are present in equal amounts. (Carbon monoxide contains one carbon atom and one oxygen atom.) And while some carbon dioxide (one carbon and two oxygen atoms) formed without the addition of UV radiation, the reactions accelerated with the addition of simulated starlight.

“These new results are immediately useful for interpreting what we see in hot Jupiter atmospheres,” said JPL exoplanet scientist Mark Swain, a study coauthor. “We’ve assumed that temperature dominates the chemistry in these atmospheres, but this shows we need to look at how radiation plays a role.”

With next-generation tools like NASA’s James Webb Space Telescope, set to launch in 2021, scientists might produce the first detailed chemical profiles of exoplanet atmospheres, and it’s possible that some of those first subjects will be hot Jupiters. These studies will help scientists learn how other solar systems form and how similar or different they are to our own.

For the JPL researchers, the work has just begun. Unlike a typical oven, theirs seals the gas in tightly to prevent leaks or contamination, and it allows the researchers to control the pressure of the gas as the temperature rises. With this hardware, they can now simulate exoplanet atmospheres at even higher temperatures: close to 3,000 degrees Fahrenheit (1,600 degrees Celsius).

“It’s been an ongoing challenge figuring out how to design and operate this system successfully, since most standard components such as glass or aluminum melt at these temperatures,” said JPL research scientist Bryana Henderson, a coauthor of the study. “We’re still learning how to push these boundaries while safely handling these chemical processes in the lab. But at the end of the day, the exciting results that come out of these experiments is worth all the extra effort.”

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