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The Atmosphere of One of The Hottest Exoplanets in The Galaxy Is Full of Metal – ScienceAlert

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Using the light of the star it orbits, astronomers have peered into the atmosphere of an exoplanet 850 light-years away. Not just any exoplanet, but one of the hottest we’ve ever found – and at least seven metals have now been identified floating around its atmosphere as gas.

The exoplanet is WASP-121b, a type of planet we call a hot Jupiter. That’s because it’s a gas giant so close to its star that its temperature rivals that of stars itself; cool stars, to be sure, but stars nevertheless.

WASP-121b is pretty famous, as far as exoplanets go. It was first discovered in 2015, an exoplanet about 1.18 times the mass and 1.81 times the size of Jupiter, on a close orbit of just 1.27 days. Two years later, it became the first exoplanet in whose stratosphere water had been found – although, given the planet’s extreme heat, it’s highly unlikely to be habitable.

Now astronomers have taken a closer look at the exoplanet’s atmosphere, and what they found has surprised them.

At temperatures between 2,500 and 3,000 degrees Celsius (roughly 4,500 and 5,500 degrees Fahrenheit), it isn’t the hottest of these exoplanets that we’ve seen.

But it is so hot that its atmosphere should be a lot simpler than what astronomers have observed in earlier studies – complex molecules should not be able to form in such high temperatures.

These earlier studies suggested that molecules containing the rare metal vanadium and a lack of titanium could explain the spectrum in earlier observations of WASP-121b’s atmosphere.

“Previous studies tried to explain these complex observations with theories that did not seem plausible to me,” said astronomer Jens Hoeijmakers of the Universities of Bern and Geneva in Switzerland.

“But it turned out that they were right. To my surprise, we actually found strong signatures of vanadium in the observations.”

Peering into exoplanet atmospheres is not an easy thing to do. First, you need the exoplanet to pass between us and the star. This is actually a good way to find exoplanets in the first place – you look for really faint, regular dips in starlight to tell you something large is orbiting the star.

To study the atmosphere, you need even fainter signals.

As the exoplanet passes in front of the star, some of the star’s light passes through the atmosphere. Depending on the elements present in the atmosphere, some wavelengths of light will be absorbed and enhanced. If you can take a full spectrum of wavelengths, these will appear as absorption and emission lines.

As you can imagine, the signal isn’t very strong, and there’s a lot of noise. So, for a start, you need good noise reduction tools that aren’t going to destroy the data you need.

The signal can also be magnified and clarified by taking multiple transit spectra and stacking them – so exoplanets with short orbital periods that allow us to take more transit spectra will be easier to analyse. An exoplanet on a 12-year orbit like Jupiter’s would not be an ideal candidate, for example. But WASP-121b’s tight orbit works well.

To obtain a strong spectrum for WASP-121b, Hoeijmakers and his team used three transits previously observed using the HARPS spectrograph instrument on the European Southern Observatory’s La Silla 3.6m telescope, and reprocessed the data.

And they found an interesting metallic cocktail in the exoplanet’s atmosphere. There was the aforementioned vanadium, of course. In addition, the team identified the spectral signatures of iron, chromium, calcium, sodium, magnesium, and nickel. Notably, there’s no titanium – consistent with the earlier findings.

“All metals evaporated as a result of the high temperatures prevailing on WASP-121b, thus ensuring that the air on the exoplanet consists of evaporated metals, among other things,” Hoeijmakers explained.

Hot Jupiters are very mysterious planets, and such analyses of their atmospheres can help us understand them. We don’t know why or how they are so close to their stars, and learning about what’s in their atmospheres can help us figure out if they formed there, or if they migrated inwards from a farther orbit.

But these studies are also helping develop the toolkit for probing planets in search of alien life. What we use to identify iron and sodium today could, with more sensitive equipment, one day help find the molecules produced and used by living organisms, such as oxygen and methane.

“After years of cataloguing what is out there, we are now no longer just taking measurements,” Hoeijmakers said

“We are really beginning to understand what the data from the instruments show us. How planets resemble and differ from each other. In the same way, perhaps, that Charles Darwin began to develop the theory of evolution after characterising countless species of animals, we are beginning to understand more about how these exoplanets were formed and how they work.”

The research has been published in Astronomy & Astrophysics.

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A Full Blue Moon Will Rise Over Metro Vancouver Skies This Halloween – 604 Now

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Travel & Outdoors

Sky watchers can take in the incredible wonder of the Hunter’s Blue Moon, which will be making a rare appearance this Halloween.

The full blue moon will be visible over North American skies on Oct. 31st. The lunar event is even more special considering it means there are two full moons in October—the Harvest Moon at the beginning of the month and the Hunter’s Moon at the end.

Typically, there is only one full moon per month. And the second full moon in a month is even more magical—because it’s a blue moon.

According to the Old Farmer’s Almanac, the timing of the full blue moon rising on Halloween night is also extremely rare.

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“Despite all the creative Halloween full moon pictures, a full moon occurring on Halloween is not a common occurrence and only happens every 18 to 19 years,” the website reads.

The Hunter’s Blue Moon also rises right before the end of Daylight Saving Time.

It’s at the perfect timing—with Halloween landing on a Saturday this year and people getting an extra hour of sleep on Sunday, as we turn back the clocks.

Hunter’s Blue Moon

When: Visible across North American skies on Saturday, Oct. 31st, 2020

For more things to do and see in Metro Vancouver and beyond, check out our Travel & Outdoors section.

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“Our Water Moon” –NASA’s Lunar Discovery – The Daily Galaxy –Great Discoveries Channel

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Moon South Pole

Our Moon has yielded some long-held secrets in recent weeks, from possible evidence of ancient life on Venus to NASA’s new discovery of large deposits of water.

Fragments of Ancient Venus Life?

Research by Yale astronomers suggests that our Moon –formed bout 4.51 billion years ago from debris left over after a giant impact between Earth and a Mars-sized body called Theia– may harbor clues that our nearest planetary neighbor, Venus, may have had an Earth-like environment billions of years ago, with water and a thin atmosphere. “Pieces of Venus — perhaps billions of them — are likely to have crashed on the moon,” suggest astronomers Sam Cabot and Greg Laughlin, as asteroids and comets slammed into Venus over the eons dislodging as many as 10 billion rocks and sent them into an orbit that intersected with Earth and Earth’s moon.

A Watery Moon

A new discovery announced today by NASA revealed that observations by the SOFIA telescope and Lunar Reconnaissance Orbiter showed signs of water in the sun-baked lunar soil, as well as in small, dark craters that go beyond past discoveries of significant deposits of water at the large, permanently shadowed craters at its poles. The new discovery that water may be distributed across the lunar surface, and not limited to cold, shadowed places sets the stage for a manned radiation-hardened moon base –where, as our Blue Planet proves, there is water, there can be life.

SOFIA Detects Water Molecules at Clavius Crater

“Prior to the SOFIA observations, we knew there was some kind of hydration. But we didn’t know how much, if any, was actually water molecules – like we drink every day – or something more like drain cleaner,” said Casey Honniball, a NASA Postdoctoral Program fellow at the agency’s Goddard Space Flight Center and a researcher at the University of Hawaii at Manoa, and the lead author of the study, Molecular water detected on the sunlit Moon by SOFIA, published in Nature Astronomy, who used infrared instruments onboard SOFIA to study the sunlit lunar surface.

The observations, which spanned a mere 10 minutes, focused on a region at high southern latitudes near the moon’s large crater, Clavius, and they revealed a strong infrared emission at a wavelength of six microns (µm) from the crater and the surrounding landscape. Warmed by the sun, something on the lunar surface was reemitting the absorbed radiation just as molecular water—plain H2O—would.

“Clues to Alien Life” –Billions of Fragments of Venus May Exist on the Moon

NASA revealed that SOFIA detected water molecules (H2O) in Clavius Crater (shown below along with an image of NASA’s Stratospheric Observatory for Infrared Astronomy –SOFIA), one of the largest craters visible from Earth, located in the Moon’s southern hemisphere. Previous observations of the Moon’s surface detected some form of hydrogen, but were unable to distinguish between water and its close chemical relative, hydroxyl (OH). Data from this location reveal water in concentrations of 100 to 412 parts per million – roughly equivalent to a 12-ounce bottle of water – trapped in a cubic meter of soil spread across the lunar surface.

"Our Water Moon" --NASA's Lunar Discovery"Our Water Moon" --NASA's Lunar Discovery

H2O on Sunlit Side

“We had indications that H2O – the familiar water we know – might be present on the sunlit side of the Moon,” said Paul Hertz, director of the Astrophysics Division in the Science Mission Directorate at NASA Headquarters in Washington. “Now we know it is there. This discovery challenges our understanding of the lunar surface and raises intriguing questions about resources relevant for deep space exploration.”

As a comparison, the Sahara desert has 100 times the amount of water than what SOFIA detected in the lunar soil. Despite the small amounts, the discovery raises new questions about how water is created and how it persists on the harsh, airless lunar surface.

Under NASA’s Artemis program, the agency is eager to learn all it can about the presence of water on the Moon in advance of sending the first woman and next man to the lunar surface in 2024 and establishing a sustainable human presence there by the end of the decade.

Apollo Missions’ Dry Moon –H2O or OH?

SOFIA’s results build on years of previous research examining the presence of water on the Moon. When the Apollo astronauts first returned from the Moon in 1969, it was thought to be completely dry. Orbital and impactor missions over the past 20 years, such as NASA’s Lunar Crater Observation and Sensing Satellite, confirmed ice in permanently shadowed craters around the Moon’s poles. Meanwhile, several spacecraft – including the Cassini mission and Deep Impact comet mission, as well as the Indian Space Research Organization’s Chandrayaan-1 mission – and NASA’s ground-based Infrared Telescope Facility, looked broadly across the lunar surface and found evidence of hydration in sunnier regions. Yet those missions were unable to definitively distinguish the form in which it was present – either H2O or OH.

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Scientists using NASA’s telescope on an airplane, the Stratospheric Observatory for Infrared Astronomy, discovered water on a sunlit surface of the Moon for the first time. SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Molecular water, H2O, was found in Clavius Crater, one of the largest craters visible from Earth in the Moon’s southern hemisphere. This discovery indicates that water may be distributed across the lunar surface, and not limited to cold, shadowed places.

SOFIA’s Infrared Zooms in on Clavius Crater

SOFIA offered a new means of looking at the Moon. Flying at altitudes of up to 45,000 feet, this modified Boeing 747SP jetliner with a 106-inch diameter telescope reaches above 99% of the water vapor in Earth’s atmosphere to get a clearer view of the infrared universe. Using its Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST), SOFIA was able to pick up the specific wavelength unique to water molecules, at 6.1 microns, and discovered a relatively surprising concentration in sunny Clavius Crater.

“Without a thick atmosphere, water on the sunlit lunar surface should just be lost to space,” said Honniball, who is now a postdoctoral fellow at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Yet somehow we’re seeing it. Something is generating the water, and something must be trapping it there.”

Several Forces at Play

Several forces could be at play in the delivery or creation of this water. Micrometeorites raining down on the lunar surface, carrying small amounts of water, could deposit the water on the lunar surface upon impact. Another possibility is there could be a two-step process whereby the Sun’s solar wind delivers hydrogen to the lunar surface and causes a chemical reaction with oxygen-bearing minerals in the soil to create hydroxyl. Meanwhile, radiation from the bombardment of micrometeorites could be transforming that hydroxyl into water.

Emergence of Life –“Played an Important Role on Evolution of the Moon”

How the water then gets stored – making it possible to accumulate – also raises some intriguing questions. The water could be trapped into tiny beadlike structures in the soil that form out of the high heat created by micrometeorite impacts. Another possibility is that the water could be hidden between grains of lunar soil and sheltered from the sunlight – potentially making it a bit more accessible than water trapped in beadlike structures.

“Accidental Discovery” –A Test Observation

For a mission designed to look at distant, dim objects such as black holes, star clusters, and galaxies, SOFIA’s spotlight on Earth’s nearest and brightest neighbor was a departure from business as usual. The telescope operators typically use a guide camera to track stars, keeping the telescope locked steadily on its observing target. But the Moon is so close and bright that it fills the guide camera’s entire field of view. With no stars visible, it was unclear if the telescope could reliably track the Moon. To determine this, in August 2018, the operators decided to try a test observation.

“It was, in fact, the first time SOFIA has looked at the Moon, and we weren’t even completely sure if we would get reliable data, but questions about the Moon’s water compelled us to try,” said Naseem Rangwala, SOFIA’s project scientist at NASA’s Ames Research Center in California’s Silicon Valley. “It’s incredible that this discovery came out of what was essentially a test, and now that we know we can do this, we’re planning more flights to do more observations.”

SOFIA’s follow-up flights will look for water in additional sunlit locations and during different lunar phases to learn more about how the water is produced, stored, and moved across the Moon. The data will add to the work of future Moon missions, such as NASA’s Volatiles Investigating Polar Exploration Rover (VIPER), to create the first water resource maps of the Moon for future human space exploration.

In the same issue of Nature Astronomy, scientists have published a paper using theoretical models and NASA’s Lunar Reconnaissance Orbiter data, pointing out that water could be trapped in small shadows, where temperatures stay below freezing, across more of the Moon than currently expected. The results can be found here.

“Farside Wakeup” –One of Largest Impacts in Solar System Rang the Moon to ‘Life’

“Water is a valuable resource, for both scientific purposes and for use by our explorers,” said Jacob Bleacher, chief exploration scientist for NASA’s Human Exploration and Operations Mission Directorate. “If we can use the resources at the Moon, then we can carry less water and more equipment to help enable new scientific discoveries.”

Image at top of page: a multi-temporal illumination map of the lunar south pole, Shackleton crater (19 km diameter) is in the center, the south pole is located approximately at 9 o’clock on its rim. The map was created from images from the camera aboard the Lunar Reconnaissance Orbiter. The South Pole is also a good target for a future human landing because robotically, it’s the most thoroughly investigated region on the Moon. (NASA/GSFC/Arizona State University).

“We know the South Pole region contain water ice and may be rich in other resources based on our observations from orbit, but, otherwise, it’s a completely unexplored world,” said Steven Clarke, deputy associate administrator of the Science Mission Directorate at NASA Headquarters in Washington. “The South Pole is far from the Apollo landing sites clustered around the equator, so it will offer us a new challenge and a new environment to explore as we build our capabilities to travel farther into space.”

The Daily Galaxy, Jake Burba, via Nature Astronomy and NASA 

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There could be lots of water on the moon, new studies suggest – CBC.ca

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The moon lacks oceans and lakes that are a hallmark of Earth, but scientists said on Monday lunar water is more widespread than previously known. Water molecules are trapped within mineral grains on the surface and more water may be hidden in ice patches residing in permanent shadows, they said.

While research 11 years ago indicated water was relatively widespread in small amounts on the moon, a team of scientists is now reporting the first definite detection of water molecules on the lunar surface. At the same time, another team is reporting that the moon possesses roughly 40,000 square kilometres of permanent shadows that could harbour hidden pockets of water in the form of ice.

Water is a precious resource and a relatively plentiful lunar presence could prove important to future astronaut and robotic missions seeking to extract and utilize water for purposes such as a drinking supply or a fuel ingredient.

A team led by Casey Honniball of NASA’s Goddard Space Flight Center in Maryland detected molecular water on the lunar surface, trapped within natural glasses or between debris grains. Previous observations have suffered from ambiguity between water and its molecular cousin hydroxyl, but the new detection used a method that yielded unambiguous findings. The results were published in the journal Nature Astronomy.

The only way for this water to survive on the sunlit lunar surfaces where it was observed was to be embedded within mineral grains, protecting it from the frigid and foreboding environment. The researchers used data from the SOFIA (Stratospheric Observatory for Infrared Astronomy) airborne observatory, a Boeing 747SP aircraft modified to carry a telescope.

“A lot of people think that the detection I’ve made is water ice, which is not true. It’s just the water molecules — because they’re so spread out they don’t interact with each other to form water ice or even liquid water,” Honniball said.

The second study, also published in the journal Nature Astronomy, focused upon so-called cold traps on the moon, regions of its surface that exist in a state of perpetual darkness where temperatures are below 163 degrees. In those temperatures, frozen water can remain stable for billions of years.

Using data from NASA’s Lunar Reconnaissance Orbiter spacecraft, researchers led by planetary scientist Paul Hayne of the University of Colorado, Boulder detected what may be tens of billions of shadows, many no bigger than a small coin. Most are located in the polar regions.

“Our research shows that a multitude of previously unknown regions of the moon could harbour water ice,” Hayne said. “Our results suggest that water could be much more widespread in the moon’s polar regions than previously thought, making it easier to access, extract and analyze.”

A high resolution mosaic of our moon’s north polar region is seen in this undated handout image taken by scientists using cameras aboard NASA’s Lunar Reconnaissance Orbiter (LRO). A new study finds there are 40,000 square kilometres of shadows, mostly near the moon’s poles, that could hide ice deposits. (Arizona State University/GSFC/NASA/Reuters)

NASA is planning a return of astronauts to the moon, a mission envisioned as paving the way for a later journey carrying a crew to Mars. Accessible sources where water can be harvested on the moon would beneficial to those endeavours.

“Water is not just constrained to the polar region. It’s more spread out than we thought it was,” Honniball said.

Another mystery that remains unsolved is the source of the lunar water.

“The origin of water on the moon is one of the big-picture questions we are trying to answer through this and other research,” Hayne said. “Currently, the major contenders are comets, asteroids or small interplanetary dust particles, the solar wind, and the moon itself through outgassing from volcanic eruptions.”

Earth is a wet world, with vast salty oceans, large freshwater lakes and ice caps that serve as water reservoirs.

“As our closest planetary companion, understanding the origins of water on the moon can also shed light on the origins of Earth’s water — still an open question in planetary science,” Hayne added.

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