Celestial Metal clouds turn scorching hot exoplanet into the universe's largest mirror

[Housecarl]

Posted for fair use.....

Metal clouds turn scorching hot exoplanet into the universe's largest mirror

"It's a planet that shouldn't exist."

www.space.com

Metal clouds turn scorching hot exoplanet into the universe's largest mirror​

By Robert Lea
published 5 days ago
"It's a planet that shouldn't exist."
Comments (9)

Astronomers have discovered the most reflective planet outside the solar system ever seen. The ultra-hot extrasolar planet, or exoplanet, acts like a cosmic mirror because it is covered by reflective clouds of metal.

The planet, designated LTT9779 b, is located around 264 light-years from Earth and reflects around 80% of the light that shines on it from its parent star. As a comparison to LTT9779 b, Earth reflects just 30% of the light that falls on it from the sun. The ultra-hot LTT9779 b is so reflective that it is the first exoplanet found that gives the solar system's shiniest planet, Venus, a run for its money; Venus has a thick layer of clouds that reflect around 75% of incident sunlight.

The exoplanet is, in turn, almost five times as wide as Earth, meaning it is also the largest cosmic mirror ever discovered. "Imagine a burning world, close to its star, with heavy clouds of metals floating aloft, raining down titanium droplets," research co-author and Diego Portales University astronomer James Jenkins said in a statement.

Related: Good news for the alien life hunt: Buried oceans may be common on icy exoplanets

While LTT9779 b was first discovered by NASA's Transiting Exoplanet Survey Satellite (TESS) mission in 2020, the world's highly reflective nature wasn't uncovered until a follow-up investigation by the European Space Agency exoplanet-hunting spacecraft, CHaracterising ExOPlanet Satellite (CHEOPS). LTT9779 b is around the size of the solar system ice giant Neptune, which, coupled with its roasting temperature, class it as an ultra-hot Neptune.

How LTT9779 b became a Neptune-sized celestial mirror​

Initially, the high reflectivity of LTT9779 b, a quality known as 'albedo,' was a mystery to scientists. This is because most planets, other than ice worlds or planets with reflective cloud layers like Venus, have low albedos as a result of their atmospheres or surfaces absorbing starlight, thus preventing it from being reflected back into space.

LTT9779 b was predicted to have a low albedo because, with a surface temperature of around 3,650 degrees Fahrenheit (2,000 degree Celsius) on the side of the exoplanet that permanently faces its star, it should be too hot to form clouds of water. This high temperature should make LTT9779 b too hot even for even clouds of metals or glass to form.

"It's a planet that shouldn't exist," says research co-author and Observatory of Côte d'Azur researcher Vivien Parmentier. "We expect planets like this to have their atmosphere blown away by their star, leaving behind bare rock."

The existence of such a planet prompted researchers to explore other theories for how these metal clouds formed. "It was really a puzzle until we realized we should think about this cloud formation in the same way as condensation forming in a bathroom after a hot shower," Parmentier added. "To steam up a bathroom, you can either cool the air until water vapor condenses, or you can keep the hot water running until clouds form because the air is so saturated with vapor that it simply can't hold anymore."

A diagram shows how LTT9779 b acts like a celestial mirror. (Image credit: ESA)

The team thinks that LTT9779 b got its metal clouds and its high albedo when its atmosphere was oversaturated with silicate and metal vaporized by scorching hot temperatures on the planet's permanent dayside.

The reflective nature of LTT9779b isn't its only extraordinary quality, however. The exoplanet is also an example of a planetary type that has eluded astronomers for decades and remains mysterious.

Ultra-hot Neptune is an example of a missing planet type​

As an ultra-hot Neptune which orbits so close to its star, LTT9779b is the first in a population of "missing planets" to be discovered. Planets of this size and mass, which orbit close to their parent stars, have been long-absent from the exoplanet catalog, which now contains over 6,000 worlds.

All other planets found so close to their parent star that they orbit them in under a day have been so-called "hot Jupiter" planets with widths around ten times that of Earth, or rocky worlds smaller than twice the size of our planet.

This left an absence of planets with sizes and mass in between these categories at close proximities to their stars. An absence that has come to be known as the "hot-Neptunian desert" by scientists.

With a size just larger than its ice-giant namesake and a 19-hour orbit, LTT9779 b sits firmly in this gap.

The planet's survival in the hot-Neptunian desert so close to its star could share an explanation with its high reflectivity characteristic.

"We believe these metal clouds help the planet to survive in the hot Neptune desert," research lead author and Marseille Astrophysics Laboratory scientist Sergio Hoyer said. "The clouds reflect light and stop the planet from getting too hot and evaporating. Meanwhile, being highly metallic makes the planet and its atmosphere heavy and harder to blow away."

LTT9779 b is likely to be the focus of extensive study over the coming years, with the exoplanet representing a fine observational target for both the James Webb Space Telescope and the Hubble Space Telescope. This should allow scientists to better understand its atmosphere, clouds, and its other characteristics.

The team’s research is published in the journal Astronomy & Astrophysics.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.

RELATED STORIES:
—  Friendless 'hot Jupiter' exoplanets may not be so lonely after all
— Ultra-hot exoplanet has an atmosphere of vaporized rock
—  James Webb Space Telescope finds water in super-hot exoplanet's atmosphere

 

[Shadow]

A planet with lots of chrome. Must be from the 50's!

Shadow

 

[wobble]

The article said it's star facing side is permanent so I want to imagine what the opposite dark side is like.

 

[night driver]

PROBABLY still FREAKIN' HOT!!

 

[Countrymouse]

hot "because" of its atmosphere's reflective qualities?

Isn't that the OPPOSITE of what "Stratospheric Geoengineering" claims their programs to "cool" earth's atmosphere (by putting a barium/aluminum 'shield' around the planet) will do?

Wonder if they really know what they are doing..............

(article below talks about using sulphur dioxide, but you can find plenty of info online about the programs that have been already ongoing for years using aluminum and barium)

White House is pushing ahead research to cool Earth by reflecting back sunlight

There are several kinds of sunlight-reflection technology, and none have been thoroughly researched due to a perceived moral hazard. But sentiment is shifting.

www.cnbc.com

White House is pushing ahead research to cool Earth by reflecting back sunlight​

Published Thu, Oct 13 2022
1:35 PM EDTUpdated Tue, Oct 18 20223:59 PM EDT

Catherine Clifford@in/catclifford/@CatClifford
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Key Points

• The White House Office of Science and Technology Policy is coordinating a five-year research plan to study ways of modifying the amount of sunlight that reaches the Earth in order to temporarily temper the effects of global warming.
• There are several kinds of sunlight-reflection technology being considered, including stratospheric aerosol injection, marine cloud brightening and cirrus cloud thinning.
• Stratospheric aerosol injection involves spraying an aerosol like sulfur dioxide into the stratosphere, and because it has the potential to affect the entire globe, often gets the most attention.
• While arguments of moral hazard have handicapped research efforts, the idea is getting more urgent attention in the worsening climate crisis.

The White House is coordinating a five-year research plan to study ways of modifying the amount of sunlight that reaches the earth to temper the effects of global warming, a process sometimes called solar geoengineering or sunlight reflection.

The research plan will assess climate interventions, including spraying aerosols into the stratosphere to reflect sunlight back into space, and should include goals for research, what’s necessary to analyze the atmosphere, and what impact these kinds of climate interventions may have on Earth, according to the White House’s Office of Science and Technology Policy. Congress directed the research plan be produced in its spending plan for 2022, which President Joe Biden signed in March.

Some of the techniques, such as spraying sulfur dioxide into the atmosphere, are known to have harmful effects on the environment and human health. But scientists and climate leaders who are concerned that humanity will overshoot its emissions targets say research is important to figure out how best to balance these risks against a possibly catastrophic rise in the Earth’s temperature.

Getting ready to research a topic is a very preliminary step, but it’s notable the White House is formally engaging with what has largely been seen as the stuff of dystopian fantasy. In Kim Stanley Robinson’s science fiction novel, “The Ministry for the Future,” a heat wave in India kills 20 million people and out of desperation, India decides to implement its own strategy of limiting the sunlight that gets to Earth.

Chris Sacca, the founder of climate tech investment fund Lowercarbon Capital, said it’s prudent for the White House to be spearheading the research effort.

“Sunlight reflection has the potential to safeguard the livelihoods of billions of people, and it’s a sign of the White House’s leadership that they’re advancing the research so that any future decisions can be rooted in science not geopolitical brinkmanship,” Sacca told CNBC. (Sacca has donated money to support research in the area, but said he has “zero financial interests beyond philanthropy” in the idea and does not think there should be private business models in the space, he told CNBC.)

Harvard professor David Keith, who first worked on the topic in 1989, said it’s being taken much more seriously now. He points to formal statements of support for researching sunlight reflection from the Environmental Defense Fund, the Union of Concerned Scientists, and the Natural Resources Defense Council, and the creation of a new group he advises called the Climate Overshoot Commission, an international group of scientists and lawmakers that’s evaluating climate interventions in preparation for a world that warms beyond what the Paris Climate Accord recommended.

To be clear, nobody is saying sunlight-reflection modification is the solution to climate change. Reducing emissions remains the priority.

“You cannot judge what the country does on solar-radiation modification without looking at what it is doing in emission reductions, because the priority is emission reductions,” said Janos Pasztor, executive director of the Carnegie Climate Governance Initiative. “Solar-radiation modification will never be a solution to the climate crisis.”

Three ways to reduce sunlight​

The idea of sunlight reflection first appeared prominently in a 1965 report to President Lyndon B. Johnson, entitled “Restoring the Quality of Our Environment,” Keith told CNBC. The report floated the idea of spreading particles over the ocean at a cost of $100 per square mile. A one percent change in the reflectivity of the Earth would cost $500 million per year, which does “not seem excessive,” the report said, “considering the extraordinary economic and human importance of climate.”

The estimated price tag has gone up since then. The current estimate is that it would cost $10 billion per year to run a program that cools the Earth by 1 degree Celsius, said Edward A. Parson, a professor of environmental law at UCLA’s law school. But that figure is seen to be remarkably cheap compared to other climate change mitigation initiatives.
A landmark report released in March 2021 from the National Academies of Sciences, Engineering, and Medicine addressed three kinds of solar geoengineering: stratospheric aerosol injection, marine cloud brightening, and cirrus cloud thinning.

Stratospheric aerosol injection would involve flying aircraft into the stratosphere, or between 10 miles and 30 miles skyward, and spraying a fine mist that would hang in the air, reflecting some of the sun’s radiation back into space.
“The stratosphere is calm, and things stay up there for a long time,” Parson told CNBC. “The atmospheric life of stuff that’s injected in the stratosphere is between six months and two years.”

Stratospheric aerosol injection “would immediately take the high end off hot extremes,” Parson said. And also it would “pretty much immediately” slow extreme precipitation events, he said.

“The top-line slogan about stratospheric aerosol injection, which I wrote in a paper more than 10 years ago — but it’s still apt — is fast, cheap and imperfect. Fast is crucial. Nothing else that we do for climate change is fast. Cheap, it’s so cheap,” Parson told CNBC.

“And it’s not imperfect because we haven’t got it right yet. It’s imperfect because the imperfection is embedded in the way it works. The same reason it’s fast is the reason that it’s imperfect, and there’s no way to get around that.”
One option for an aerosol is sulfur dioxide, the cooling effects of which are well known from volcanic eruptions. The 1991 eruption of Mount Pinatubo, for instance, spewed thousands of tons of sulfur dioxide into the stratosphere, causing global temperatures to drop temporarily by about 1 degree Fahrenheit, according to the U.S. Geological Survey.

A giant volcanic mushroom cloud explodes some 20 kilometers high from Mount Pinatubo above almost deserted US Clark Air Base, on June 12, 1991 followed by another more powerful explosion. The eruption of Mount Pinatubo on June 15, 1991 was the second largest volcanic eruption of the twentieth century.
Arlan Naeg | Afp | Getty Images

There’s also a precedent in factories that burn fossil fuels, especially coal. Coal has some sulfur that oxidizes when burned, creating sulfur dioxide. That sulfur dioxide goes through other chemical reactions and eventually falls to the earth as sulfuric acid in rain. But during the time that the sulfur pollution sits in the air, it does serve as a kind of insulation from the heat of the sun.

Ironically, as the world reduces coal burning to curb the carbon dioxide emissions that cause global warming, we’ll also be eliminating the sulfur dioxide emissions that mask some of that warming.

“Sulfur pollution that’s coming out of smokestacks right now is masking between a third and a half of the heating signal from the greenhouse gases humans have already emitted into the atmosphere,” Parson said.

In other words, we’ve been doing one form of sunlight reflection for decades already, but in an uncontrolled fashion, explained Kelly Wanser, the executive director of SilverLining, an organization promoting research and governance of climate interventions.

“This isn’t something totally new and Frankenstein — we’re already doing it; we’re doing it in the most dirty, unplanned way you could possibly do it, and we don’t understand what we’re doing,” Wanser told CNBC.
Spraying sulfur in the stratosphere is not the only way of manipulating the amount of sunlight that gets to the Earth, and some say it’s not the best option.

“Sulfur dioxide is likely not the best aerosol and is by no means the only technique for this. Cloud brightening is a very promising technique as well, for example,” Sacca told CNBC.

Marine cloud brightening involves increasing the reflectivity of clouds that are relatively close to the surface of the ocean with techniques like spraying sea salt crystals into the air. Marine cloud brightening generally gets less attention than stratospheric aerosol injection because it affects a half dozen to a few dozen miles and would potentially only last hours to days, Parson told CNBC.

Cirrus cloud thinning, the third category addressed in the 2021 report from the National Academies, involves thinning mid-level clouds, between 3.7 and 8.1 miles high, to allow heat to escape from the Earth’s surface. It is not technically part of the “solar geoengineering” umbrella category because it does not involve reflecting sunlight, but instead involves increasing the release of thermal radiation.

Known risks to people and the environment​

There are significant and well-known risks to some of these techniques — sulfur dioxide aerosol injection, in particular.
First, spraying sulfur into the atmosphere will “mess with the ozone chemistry in a way that might delay the recovery of the ozone layer,” Parson told CNBC.

The Montreal Protocol adopted in 1987 regulates and phases out the use of ozone depleting substances, such as hydrochlorofluorocarbons (HCFCs) which were commonly used in refrigeration and air conditioners, but that healing process is still going on.

Also, sulfates injected into the atmosphere eventually come down as acid rain, which affects soil, water reservoirs, and local ecosystems.

Third, the sulfur in the atmosphere forms very fine particulates that can cause respiratory illness.

The question, then, is whether these known effects are more or less harmful than the warming they would offset.
“Yes, damaging the ozone is bad, acid deposition is bad, respiratory illness is bad, absolutely. And spraying sulfur in the stratosphere would contribute in the bad direction to all of those effects,” Parson told CNBC. “But you also have to ask, how much and relative to what?”

The sulfur already being emitted from the burning of fossil fuels is causing environmental damage and is already killing between 10 million to 20 million people a year due to respiratory illness, said Parson. “So that’s the way we live already,” he said.

Meanwhile, “the world is getting hotter, and there will be catastrophic impacts for many people in the world,” said Pasztor.

“There’s already too much carbon out there. And even if you stop all emissions today, the global temperature will still be high and will remain high for hundreds of years. So, that’s why scientists are saying maybe we need something else, in addition — not instead of — but maybe in addition to everything else that is being done,” he said. “The current action/nonaction of countries collectively — we are committing millions of people to death. That’s what we’re doing.”
For sunlight-reflection technology to become a tool in the climate change mitigation toolbox, awareness among the public and lawmakers has to grow slowly and steadily, according to Tyler Felgenhauer, a researcher at Duke University who studies public policy and risk.

“If it is to rise on to the agenda, it’ll be kind of an evolutionary development where more and more environmental groups are willing to state publicly that they’re for research,” Felgenhauer told CNBC. “We’re arguing it’s not going to be some sort of one big, bad climate event that makes us all suddenly adopt or be open to solar geoengineering — there will be more of a gradual process.”

Research it now or be caught off guard later?​

Some environmentalists consider sunlight relfection a “moral hazard,” because it offers a relatively easy and inexpensive alternative to doing the work of reducing emissions.

One experiment to study stratospheric aerosols by the Keutsch Group at Harvard was called off in 2021 due to opposition. The experiment would “threaten the reputation and credibility of the climate leadership Sweden wants and must pursue as the only way to deal effectively with the climate crisis: powerful measures for a rapid and just transition to zero emission societies, 100% renewable energy and shutdown of the fossil fuel industry,” an open letter from opponents said.

But proponents insist that researching sunlight-modification technologies should not preclude emissions-reduction work.

“Even the people like me who think it’s very important to do research on these things and to develop the capabilities all agree that the urgent top priority for managing climate change is cutting emissions,” Parson told CNBC.
Keith of Harvard agreed, saying that “we learn more and develop better mechanism for governance.”
Doing research is also important because many onlookers expect that some country, facing an unprecedented climate disaster, will act unilaterally to will try some version of sunlight modification anyway — even if it hasn’t been carefully studied.

“In my opinion, it’s more than 90 percent likely that within the next 20 years, some major nation wants to do this,” Parson said.

Sacca put the odds even higher.

“The odds are 100 percent that some country pursues sunlight reflection, particularly in the wake of seeing millions of their citizens die from extreme weather,” Sacca told CNBC. “The world will not stand idly by and leaders will feel compelled to take action. Our only hope is that by doing the research now, and in public, the world can collaboratively understand the upsides and best methods for any future project.”

Correction: The Climate Overshoot Commission has not issued a formal statement of support for sunlight reflection.

 

[jed turtle]

The Air Force has been telling us for years that they will “own the weather by 2025”. Must be why we are having this new monsoon season here in Maine for the first time in our history. At least it kept the Canadian smoke away. But have had to run the generator several times this summer because not enough sunlight is getting to the solar panels. Usually never have to run the generator at all the entire summer. Since June 2 it has been raining almost all the time. Maybe get a day or two a week without rain and clouds.