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Entertainment

‘Black Art: In the Absence of Light’ Reveals a History of Neglect and Triumph

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“This is Black art. And it matters. And it’s been going on for two hundred years. Deal with it.”

So declares the art historian Maurice Berger toward the beginning of “Black Art: In the Absence of Light,” a rich and absorbing documentary directed by Sam Pollard (“MLK/FBI”) and debuting on HBO Tuesday night.

The feature-length film, assembled from interviews with contemporary artists, curators and scholars, was inspired by a single 1976 exhibition, “Two Centuries of Black American Art,” the first large-scale survey of African-American artists. Organized by the artist David C. Driskell, who was then-head of the art department at Fisk University, it included some 200 works dating from the mid-18th to the mid-20th century, and advanced a history that few Americans, including art professionals, even knew existed.

The press gave that survey a mixed reception. Some writers griped that it was more about sociology than art (Driskell himself didn’t entirely disagree). But the show was a popular hit. At the Los Angeles County Museum of Art, where it originated, and then at major museums in Dallas, Atlanta and Brooklyn, people lined up to see it.

What they were seeing was that Black artists had always done distinctive work in parallel to, and some within, a white-dominated mainstream that ignored them. And they were seeing that Black artists had consistently made, and are continuing to make, some of the most conceptually exciting and urgent-minded American art, period — a reality only quite recently acknowledged by the art world at large, as reflected in exhibitions, sales and critical attention.

The HBO documentary introduces us to this history of long neglect and recent correction through the eloquent voices of three people who lived both sides of it: Driskell, a revered painter and teacher; Mary Schmidt Campbell, the president of Spelman College in Atlanta, Ga., and former director of the Studio Museum in Harlem; and Berger, an esteemed art historian and curator. (The film is dedicated to the two men, both of whom died from complications related to Covid-19 in 2020, Driskell at 88, Berger at 63.)

They’re surrounded by artists, most of them painters, of various generations. Some had careers that were well underway by 1976 (Betye Saar, for example, and Richard Mayhew, who was in the survey). Others were, at that point, just starting out in the field. (Kerry James Marshall remembers being blown away by a visit to the show when he was 21). Still others — Kehinde Wiley (born 1977) and Jordan Casteel (born 1989) — weren’t born when the survey opened but still count themselves among its beneficiaries.

The question arises early in the film — in a 1970s “Today Show” interview with Driskell by Tom Brokaw — as to whether the very use of the label “Black American art” isn’t itself a form of imposed isolation. Yes, Driskell says, but in this case a strategic one. “Isolation isn’t, and never was, the Black artist’s goal. He has tried to be part and parcel of the mainstream, only to be shut out. Had this exhibition not been organized many of the artists in it would never have been seen.”

The film refers, in shorthand form, to past examples of shutting-out. There’s a reference to the Metropolitan Museum’s 1969 “Harlem on My Mind: Cultural Capital of Black America, 1900-1968,” an exhibition that was advertised as introducing Black creativity to the Met but that contained little in the way of art. And mention is made of artists’ protests of the Whitney Museum’s 1971 survey “Contemporary Black Artists in America,” which was left entirely in the hands of a white curator.

A book of essays titled “Black Art Notes,” printed that year in response to the Whitney show, accused white museums of “artwashing” through the token inclusion of African-American work, a charge that has continuing pertinence. (The collection was recently reissued, in a facsimile edition, by Primary Information, a nonprofit press in Brooklyn.) Even before the Met and Whitney shows, Black artists saw the clear necessity of taking control of how and where their art was seen into their own hands. Ethnically specific museums began to spring up — outstandingly, in 1968, the Studio Museum in Harlem.

We’re talking about a dense, complex history. No one film can hope to get all of it, and this one leaves a lot out. (Mention of the Black Power movement is all but absent here.) Still, there’s a lot, encapsulated in short, deft commentary by scholars and curators, among them Campbell, Sarah Lewis of Harvard University, Richard J. Powell of Duke University, and Thelma Golden, the current director and chief curator of the Studio Museum. (Golden is a consulting producer of the film. Henry Louis Gates, Jr. is its executive producer.)

Rightfully, and delightfully, the majority of voices are those of active artists. Faith Ringgold, now 90, wasn’t in the 1976 show, or in big museums much at all, because, she asserts, her work was too political and because she’s female. (Of the 63 artists in “Two Centuries of Black American Art,” 54 were male.) Her solution? “I just stay out till I get in,” she says. (And persisting has paid off: Her monumental 1967 painting “American People Series #20: Die” has pride of place in the Museum of Modern Art’s current permanent collection rehang.)

Particularly interesting are segments showing artists at work and talking about what they’re doing as they’re doing it. We visit Marshall in his studio as he explains the many, many paint colors he uses that are “black.” We follow Fred Wilson into museum storage as he excavated objects that will become part of one of his history-baring installations. We watch Radcliffe Bailey transform hundreds of discarded piano keys into a Middle Passage ocean. And we tag along with the portraitist Jordan Casteel, who recently wrapped up a well-received show at the New Museum, as she seeks out sitters on Harlem streets.

There’s no question that the visibility of African-American artists in the mainstream is way higher now than it’s ever been. (Thank you, Black Lives Matter.) A big uptick in shows is one measure. Landmark events like the 2018 unveiling of the Obama portraits by Wiley and Amy Sherald is another.

In an interview in the film Sherald brings up this sudden surge of attention. “A lot of galleries are now picking up Black artists,” she says. “There’s this gold rush.” But where some observers would see the interest as just a next-hot-thing marketing trend driven by a branding of “Blackness,” she doesn’t. “I say it’s because we’re making some of the best work, and most relevant work.”

The point of Pollard’s film, which was also the point of Driskell’s 1976 survey, is to demonstrate that, and to demonstrate that Black artists have been making some of the best work and the most relevant work for decades, centuries. But they’ve been making it mostly on the margins, beyond the white art world’s spotlights.

The artist Theaster Gates, who appears toward the end of the film, sees the advantage, even the necessity, of that positioning.

“Black art means that sometimes I’m making when no one’s looking,” he says. “For the most part that has been the truth of our lives. Until we own the light, I’m not happy. Until we’re in our own houses of exhibitions, of discovery, of research, until we’ve figured out a way to be masters of the world, I’d rather work in darkness. I don’t want to work only when the light comes on. My fear is that we’re being trained and conditioned to only make if there’s a light, and that makes us codependent upon a thing we don’t control. Are you willing,” he asks his fellow artists, “to make in the absence of light?”

Driskell, to whom this film really belongs and with whose presence it concludes, also leaves the question of the future of Black art open-ended. Around it, he’s says, “there’s been an awakening, an enlightenment through education, a desire to want to know. On the other hand, in the words of Martin Luther King Jr. : We haven’t reached the promised land. We’ve got a long way to go.”

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Science

Distant ‘Baby’ Black Holes Are Behaving Strangely, And Scientists Are Perplexed

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Radio images of the sky have revealed hundreds of ‘baby’ and supermassive black holes in distant galaxies, with the galaxies’ light bouncing around in unexpected ways.

Galaxies are vast cosmic bodies, tens of thousands of light years in size, made up of gas, dust, and stars (like our Sun).

 

Given their size, you’d expect the amount of light emitted from galaxies would change slowly and steadily, over timescales far beyond a person’s lifetime.

But our research, published in the Monthly Notices of the Royal Astronomical Society, found a surprising population of galaxies whose light changes much more quickly, in just a matter of years.

What is a radio galaxy?

Astronomers think there’s a supermassive black hole at the centre of most galaxies. Some of these are ‘active’, which means they emit a lot of radiation.

Their powerful gravitational fields pull in matter from their surroundings and rip it apart into an orbiting donut of hot plasma called an ‘accretion disk’.

This disk orbits the black hole at nearly the speed of light. Magnetic fields accelerate high-energy particles from the disk in long, thin streams or ‘jets’ along the rotational axes of the black hole. As they get further from the black hole, these jets blossom into large mushroom-shaped clouds or ‘lobes’.

This entire structure is what makes up a radio galaxy, so called because it gives off a lot of radio-frequency radiation. It can be hundreds, thousands or even millions of light years across and therefore can take aeons to show any dramatic changes.

 

Astronomers have long questioned why some radio galaxies host enormous lobes, while others remain small and confined. Two theories exist. One is that the jets are held back by dense material around the black hole, often referred to as frustrated lobes.

However, the details around this phenomenon remain unknown. It’s still unclear whether the lobes are only temporarily confined by a small, extremely dense surrounding environment – or if they’re slowly pushing through a larger but less dense environment.

The second theory to explain smaller lobes is the jets are young and have not yet extended to great distances.

Hercules A’s supermassive black hole emitting high energy particle jets into radio lobes.  (NASA/ESA/NRAO)

Old ones are red, babies are blue

Both young and old radio galaxies can be identified by a clever use of modern radio astronomy: looking at their ‘radio colour’.

We looked at data from the GaLactic and Extragalactic All Sky MWA (GLEAM) survey, which sees the sky at 20 different radio frequencies, giving astronomers an unparalleled ‘radio colour’ view of the sky.

 

From the data, baby radio galaxies appear blue, which means they’re brighter at higher radio frequencies. Meanwhile the old and dying radio galaxies appear red and are brighter in the lower radio frequencies.

We identified 554 baby radio galaxies. When we looked at identical data taken a year later, we were surprised to see 123 of these were bouncing around in their brightness, appearing to flicker. This left us with a puzzle.

Something more than one light year in size can’t vary so much in brightness over less than one year without breaking the laws of physics. So, either our galaxies were far smaller than expected, or something else was happening.

Luckily, we had the data we needed to find out.

Past research on the variability of radio galaxies has used either a small number of galaxies, archival data collected from many different telescopes, or was conducted using only a single frequency.

For our research, we surveyed more than 21,000 galaxies over one year across multiple radio frequencies. This makes it the first ‘spectral variability’ survey, enabling us to see how galaxies change brightness at different frequencies.

 

Some of our bouncing baby radio galaxies changed so much over the year we doubt they are babies at all. There’s a chance these compact radio galaxies are actually angsty teens rapidly growing into adults much faster than we expected.

While most of our variable galaxies increased or decreased in brightness by roughly the same amount across all radio colours, some didn’t. Also, 51 galaxies changed in both brightness and colour, which may be a clue as to what causes the variability.

Artist’s impression of SKA-mid (left) and SKA-low (right) telescopes. (SKAO/ICRAR/SARAO)

Three possibilities for what is happening

1) Twinkling galaxies

As light from stars travels through Earth’s atmosphere, it is distorted. This creates the twinkling effect of stars we see in the night sky, called ‘scintillation’. The light from the radio galaxies in this survey passed through our Milky Way galaxy to reach our telescopes on Earth.

Thus, the gas and dust within our galaxy could have distorted it the same way, resulting in a twinkling effect.

2) Looking down the barrel

In our three-dimensional Universe, sometimes black holes shoot high energy particles directly towards us on Earth. These radio galaxies are called ‘blazars’.

Instead of seeing long thin jets and large mushroom-shaped lobes, we see blazars as a very tiny bright dot. They can show extreme variability in short timescales, since any little ejection of matter from the supermassive black hole itself is directed straight towards us.

3) Black hole burps

When the central supermassive black hole ‘burps’ some extra particles they form a clump slowly travelling along the jets. As the clump propagates outwards, we can detect it first in the ‘radio blue’ and then later in the ‘radio red’.

So we may be detecting giant black hole burps slowly travelling through space.

Where to now?

This is the first time we’ve had the technological ability to conduct a large-scale variability survey over multiple radio colours. The results suggest our understanding of the radio sky is lacking and perhaps radio galaxies are more dynamic than we expected.

As the next generation of telescopes come online, in particular the Square Kilometre Array (SKA), astronomers will build up a dynamic picture of the sky over many years.

In the meantime, it’s worth watching these weirdly behaving radio galaxies and keeping a particularly close eye on the bouncing babies, too.

Kathryn Ross, PhD Student, Curtin University and Natasha Hurley-Walker, Radio Astronomer, Curtin University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 

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Science

Firefly will light up the moon with $93M lunar lander contract from NASA – TechCrunch

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NASA has awarded Firefly Aerospace a $93.3 million contract to take a lunar lander module loaded with experiments to the surface of the moon. While the company will not be performing the launch itself, it will be providing the spacecraft and “Blue Ghost” lander for the 2023 mission.

The space agency made the award as part of its ongoing Commercial Lunar Payload Services, under which several other non-prime space companies have been selected for similar work: Blue Origin, Astrobotic, Masten and so on.

This particular contract was first publicized to its CLPS partners back in September, which would have submitted bids for the project; Firefly clearly carried the day.

“We’re excited another CLPS provider has won its first task order award,” said NASA associate administrator for science Thomas Zurbuchen in a release announcing the contract. The last few years have seen many such firsts as NASA has increasingly embraced the commercial sector in providing everything from launch services to satellite and spacecraft manufacturing.

It’s not exactly Firefly’s first order from NASA, though: Its national security subsidiary Firefly Black (ominous) will be launching two cubesats for the Venture Class Launch Service Demo-2 mission. But this is larger and more complex by a huge margin (not to mention more expensive).

This will be the maiden lunar voyage for Firefly’s Blue Ghost lander, which it’s been working on for the last few years in anticipation of renewed interest in the moon. It will hold the 10 scientific payloads, which NASA describes here, including a new laser reflector array and an experimental radiation-tolerant computer. There’s a lot to be loaded up, but Blue Ghost should have 50kg of space left over for anyone else who wants a ride to the moon.

Everything is going to Mare Crisium, a basin on the “light” or near side of the moon, where hopefully they will contribute valuable observations and experiments to inform future visits to and habitation on the moon.

Firefly will also be providing the spacecraft that will take the lander into lunar space, and will be responsible for getting it off the Earth in the first place — the company told me they’re evaluating options for that. By the time 2023 rolls around there should be plenty of rides to choose from, and indeed Firefly’s own Alpha launch vehicle may be flying by then, though it’s not ready to commit to a lunar insertion orbit mission today. The company plans to have its first Alpha flight in March.

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Science

Teenage astronomers discover four new exoplanets 200 light years away from Earth

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A pair of high schoolers are being commended for making a major astronomical discovery after they identified four new planets in orbit around a star approximately 200 light years away from Earth.

What are the details?

The two students, 16-year-old Kartik Pinglé and 18-year-old Jasmine Wright, both of whom attend schools in Massachusetts, were elated at taking part in the discovery and wrote about it in a peer-reviewed paper published by the Astronomical Journal last week.

The finding may make them the youngest astronomers yet to make such a major discovery, according to a press release about the news published by the Center for Astrophysics, a collaboration between Harvard University and the Smithsonian Institution.

The students made their discovery as part of the CFA’s “Student Research Mentoring Program,” an initiative that pairs students interested in research with real-world scientists who then together embark on a year-long project.

As part of the program, the high schoolers were selected to work alongside Tansu Daylan, a postdoctoral researcher at the Massachusetts Institute of Technology, analyzing data from the Transiting Exoplanet Survey Satellite (TESS), a satellite that orbits the Earth and surveys nearby bright stars hoping to discover new planets.

The team focused on a nearby Sun-like star referred to as TESS Object of Interest 1233 to perceive whether or not planets were in orbit around it.

“We were looking to see changes in light over time,” Pinglé explained regarding the research. “The idea being that if the planet transits the star, or passes in front of it, it would [periodically] cover up the star and decrease its brightness.”

While probing the star, the students had hoped to discover at least one planet, but to their surprise, they ended up finding four.

“I was very excited and very shocked,” Wright said of the discovery. “We knew this was the goal of Daylan’s research, but to actually find a multiplanetary system, and be part of the discovering team, was really cool.”

According to the research paper, the three outer planets are considered “sub-Neptunes,” or gaseous planets that are smaller than but otherwise similar to our solar system’s planet of the same name, while the innermost planet is considered a “super-Earth” due its large size and rockiness.

What else?

The program’s director, Clara Sousa-Silva, noted that Pinglé and Wright’s achievement is rare.

“Although [it] is one of the goals of the SRMP, it is highly unusual for high-schoolers to be co-authors on journal papers,” she said in the press release.

Daylan added that it was a “win-win” to work alongside Pinglé and Wright and make a major discovery

“As a researcher, I really enjoy interacting with young brains that are open to experimentation and learning and have minimal bias,” he said. “I also think it is very beneficial to high school students, since they get exposure to cutting-edge research and this prepares them quickly for a research career.”

According to the press release, Pinglé, who is still just a junior in high school, is considering studying applied mathematics or astrophysics after graduating, while Wright has been accepted into a five-year master of astrophysics program at the University of Edinburgh in Scotland.

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Entertainment

‘Supernova’ review: Colin Firth and Stanley Tucci light up the end-of-life drama

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Firth’s Sam and Tucci’s Tusker have been together for decades, and they’re introduced on a cross-country trek in a beat-up old camper. It’s what amounts to a last hurrah, with Tusker having pushed his partner to perform a piano recital, stopping to see family along the way.

Both are keenly aware that the hourglass is running out on the life they’ve known. Tusker’s condition is gradually worsening, with occasional moments where he wanders off or struggles to articulate thoughts. He’s mostly fine now, but his inevitable deterioration — and the unwelcome prospect of “becoming a passenger” in his own body, as he says — looms like a shadow over them.

As for Sam, the trip is dogged by the fact that he’ll soon be a full-time caretaker, a role to which he has committed himself that nevertheless scares him. “You’re not supposed to mourn someone while they’re still here,” Tusker observes, summing up Sam’s uncomfortable plight.

“Supernova” isn’t a great title for a movie like this — it’s a crafty play off the pair’s interest in stargazing — although it’s oddly appropriate, since the two stars keep things watchable even when there’s nothing much happening, which is most of the time. In that regard, the film joins a long roster of end-of-life romances, in this case unfolding in what feels like slow motion.

Marking the second writing-directing effort from actor Harry Macqueen, this British production doesn’t bother with flashbacks or much reminiscing about the couple’s relationship. All that history comes in the form of casual exchanges and small gestures that reflect a lifetime together, as touchingly conveyed by Firth and Tucci, whose real-life friendship surely contributes to that shorthand. (The latter will be featured in a CNN food and travel show premiering in February.)

As understated as the movie is, the emotion of the situation comes through loud and clear. While the pacing might have benefited from a few more detours or details, the audience has a pretty good understanding of where this road began and where it leads.

“Supernova” is by any measure a modest production, but it accomplishes what it sets out to do: Creating a touching, low-key showcase for its stars, one that allows them to cast a bright light.

“Supernova” premieres January 29 in select theaters and February 16 on demand. It’s rated R.

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Science

The Full Moon Changes How People Sleep Without Us Ever Realising, Says Study

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In modern times, a great deal of research has focused on the way that artificial light sources mess up our sleep and health, due to the unnatural effects of illumination after the Sun goes down.

 

But just how unnatural is night-time light anyway? After all, humans have always been exposed to variable levels of light at night, due to reflections of sunlight from the waxing and waning Moon – and this shifting radiance stimulates us in ways we aren’t fully aware of, new research suggests.

“Moonlight is so bright to the human eye that it is entirely reasonable to imagine that, in the absence of other sources of light, this source of nocturnal light could have had a role in modulating human nocturnal activity and sleep,” a team of researchers, led by senior author and neurobiologist Horacio de la Iglesia from the University of Washington, explain in a new study.

“However, whether the Moon cycle can modulate human nocturnal activity and sleep remains a matter of controversy.”

To investigate the mystery, the researchers fitted over 500 participants with wrist-based activity monitors, to track their sleep patterns, and conducted the experiment in vastly different locales.

Firstly, they involved 98 participants from the Toba-Qom people, an indigenous community living in the Formosa province of Argentina. Some of these rural participants in the experiment had no access to electricity, others had limited access in their homes, while a final contingent lived in an urban setting with full access to electricity.

 

In a separate experiment, the researchers tracked the sleep of 464 college students living in the Seattle area – a major, modernised city with all the electrified trappings of post-industrial society.

Tracking the participants’ sleep activity over the lunar month cycle, the researchers found the same kind of pattern could be seen in their sleep and waking, regardless of where the volunteers lived.

“We see a clear lunar modulation of sleep, with sleep decreasing and a later onset of sleep in the days preceding a full Moon,” de la Iglesia says.

“Although the effect is more robust in communities without access to electricity, the effect is present in communities with electricity, including undergraduates at the University of Washington.”

While there was some variance between the results, in general, the data showed that sleep tends to start later and overall lasts a shorter amount of time on the nights leading up to a full Moon, when moonlight provided by the waxing Moon is brighter in the hours following dusk.

While the sample size studied here is not especially large – and there’s certainly more research that could be done here to expand upon these results – that the same pattern was observed in two distinct populations living in separate countries, and with such varying levels of access to electricity between all the volunteers, does tell us some important things, the team says.

 

“Together, these results strongly suggest that human sleep is synchronised with lunar phases regardless of ethnic and sociocultural background, and of the level of urbanisation,” the researchers write in their paper.

As for what gives rise to these effects, the researchers contend that extended nocturnal activity stimulated by moonlight could be an evolutionary adaptation carried over from the time of pre-industrial human societies – with the ability to stay up and do more under a brilliant full Moon benefitting all kinds of traditional customs still enjoyed by peoples without electricity today.

“At certain times of the month, the Moon is a significant source of light in the evenings, and that would have been clearly evident to our ancestors thousands of years ago,” says first author and sleep biologist Leandro Casiraghi.

According to interviews with Toba/Qom individuals, moonlit nights are still known for high hunting and fishing activity, increased social events, and heightened sexual relations between men and women.

“Although the true adaptive value of human activity during moonlit nights remains to be determined, our data seem to show that humans – in a variety of environments – are more active and sleep less when moonlight is available during the early hours of the night,” the researchers explain.

“This finding, in turn, suggests that the effect of electric light on modern humans may have tapped into an ancestral regulatory role of moonlight on sleep.”

The findings are reported in Science Advances.

 

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Science

Skull of rare dinosaur sheds light on creature’s bizarre hollow head tube

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A reconstruction of the head of the Parasaurolophus cyrtocristatus based on newly discovered remains.


Andrey Atuchin

A spectacularly preserved partial skull belonging to the rare dinosaur species Parasaurolophus cyrtocristatus has been discovered and analyzed for the first time in 97 years. 

The skull, detailed in a new study in the journal PeerJ, shows off the intact structure of the creature’s signature tube-shaped nasal passage, offering new clues into the evolution of the bizarre crest, a subject of debate among paleontologists for decades. 

“My jaw dropped when I first saw the fossil,” Terry Gates, a paleontologist from North Carolina State University and lead author of the paper, said in a statement Monday. “I’ve been waiting for nearly 20 years to see a specimen of this quality.” 

The tube-like crest had an internal network of airways for breathing, but it could have also been used for communicating. 

“Over the past 100 years, ideas for the purpose of the exaggerated tube crest have ranged from snorkels to super sniffers,” said David Evans, vice president of natural history at the Royal Ontario Museum. “But after decades of study, we now think these crests functioned primarily as sound resonators and visual displays used to communicate within their own species.”

Here’s a closer look at the skull of Parasaurolophus as originally exposed in the badlands of New Mexico. 


Doug Shore/Denver Museum of Nature and Science

The partial dinosaur skull was discovered by Smithsonian ecology fellow Erin Spear in 2017 while Spear explored northwestern New Mexico as part of a Denver Museum of Nature and Science team of paleontologists.

The three species of Parasaurolophus currently recognized have been found in dig sites from Alberta, Canada, all the way to New Mexico, in rocks that date back between 77 million and 73.5 million years. 

This is a reconstruction of a group of Parasaurolophus dinosaurs crossing paths with a tyrannosaurid in the subtropical forests of New Mexico, 75 million years ago.


Andrey Atuchin/Denver Museum of Nature and Science

The new study found for the first time a way to connect the tube-crested dinosaur species found in southern North America to the northern species found in Alberta, Canada. The skull specimen shows that the dinosaur’s crest was formed much like the crests of other, related duck-billed dinosaurs. 

“This specimen is a wonderful example of amazing creatures evolving from a single ancestor,” said Joe Sertich, curator of dinosaurs at the Denver Museum of Nature and Science and the leader of the team that discovered the skull. 

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.

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Science

ISS Tool Spots Blue Light Jets Shooting Upwards

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Do you ever wonder about the many experiments that go on at the International Space Station (ISS)? What do astronauts study in this orbiting laboratory?

RELATED: ASTRONOMERS CREATE ‘FIFTH STATE OF MATTER’ IN THE INTERNATIONAL SPACE STATION

Well, many things of course but one of them is the weather: particularly the kind of weather events that can not be seen from Earth. These are called blue jets, and elves (short for Emissions of Light and Very Low Frequency Perturbations due to Electromagnetic Pulse Sources), and their monitoring is made possible by a European tool named the Atmosphere-Space Interactions Monitor (ASIM) observatory.

ASIM, installed in the space station in 2018, consists of a collection of optical cameras, photometers, and an X and gamma-ray detector and it’s there to detect electrical discharges from weather events that can only be spotted in space. Understanding these galactical weather events is crucial to understanding not only the weather on Earth but also the concentration of greenhouse gasses in Earth’s atmosphere.

What are elves and blue jets?

But what are blue jets and elves? Blue jets, as their name denotes, are streams of blue-colored lightning that do not head toward land but instead shoot upward into space. As the images show, they are quite beautiful to see.

Elves, on the other hand, are light emissions that appear as rapidly expanding rings in the ionosphere.

Both elves and blue jets were spotted by ASIM on Feb. 26, 2019 near Nauru, a small island in the central Pacific Ocean. They have now been described in a paper published in Nature on Jan. 20, 2021. The study describes these events in great detail capturing their awe-inspiring beauty even without the use of images.

It is definitely worth a read if you are a fan of space phenomena. It is also indicative of all we still have to discover on our precious planet.

“This paper is an impressive highlight of the many new phenomena ASIM is observing above thunderstorms and shows that we still have so much to discover and learn about our Universe,” said in a statement Astrid Orr, ESA’s Physical Sciences Coordinator for human and robotic spaceflight.



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Science

Groundbreaking New Laser System Cuts Through Earth’s Atmosphere Like It’s Nothing

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To artists and romantics, the twinkling of stars is visual poetry; a dance of distant light as it twists and bends through a turbulent ocean of air above our heads.

Not everybody is so enamoured with our atmosphere’s distortions. To many scientists and engineers, a great deal of research and ground-to-satellite communication would be a whole lot easier if the air simply wasn’t there.

 

Losing our planet’s protective bubble of gases isn’t exactly a popular option. But Australian and French researchers have teamed up to design the next best thing – a system that guides light through the tempestuous currents of rippling air with the flick of a mirror.

The result is a laser link capable of holding its own through the atmosphere with unprecedented stability.

While astronomers have a few tricks up their sleeve to correct for the atmosphere’s distortions on incoming light, it’s been a challenge to emit a coherent beam of photons from the ground to a distant receiver so they keep together and on point.

Keeping transmissions on target and coherent – with their phases remaining neatly in line – through hundreds of kilometres of shifting air would allow us to link highly precise measurement tools and communications systems.

Satellites could probe for ores or evaluate water tables with improved precision. High-speed data transfer could require less power, and contain more information.

Lead author Ben Dix-Matthews, an electrical engineer with the International Centre for Radio Astronomy Research in Australia, explained the technology to ScienceAlert.

 

“The active terminal essentially uses a small four-pixel camera, which measures the sideways movement of the received beam,” says Dix-Matthews.

“This position measurement is then used to actively control a steerable mirror that keeps the received beam centred and removes the sideways movement caused by the atmosphere.”

In effect, the system can be used to compensate for the warping effects of the moving air in three dimensions – not just up and down, or left and right, but along the beam’s trajectory, keeping the link centred and its phases in order.

So far it’s only been tested across a relatively short distance of 265 metres (about 870 feet). About 715 metres (just under half a mile) of optical fibre cable was run underground between the transmitter and receiver to carry a beam for comparison.

The results were so stable they could be used to connect the kinds of optical atomic clocks used to test fundamental physics, such as Einstein’s theories of relativity.

With the proof of concept demonstrated, there’s no reason to think a similar technique won’t one day be aiming for the sky, and beyond. Though there are a few hurdles that need to be overcome first.

 

“During this experiment we had to do the initial alignment by hand, using a visible guide laser that was in line with the stabilised infrared beam,” Dix-Matthews told ScienceAlert.

“When making links between optical atomic clocks, it would be good to have a way of doing this coarse alignment more easily.”

Fortunately Dix-Matthews’ French collaborators are working on a device that will speed up the initial coarse alignment process, promising a second generation of laser link technology that won’t require such an involved set-up.

The team also found temperature variations in the equipment affected the phase’s stability, limiting the duration of the signal to around 100 seconds. This hurdle will also be the focus of future improvements.

We might not need to wait long. The researchers are already making headway on upgrades for their system.

“We have started using a high-power laser amplifier that should help us deal with the larger power losses expected over longer distances, such as to space,” says Dix-Matthews.

“We have also completely rebuilt our active terminal to make it more sensitive to low received powers and make it more effective at cancelling out the movement of the received beam.”

With orbiting technology rapidly becoming a major focus for many data providers, potentially filling our skies with satellites, innovations that make linking communications systems across our atmosphere will only become more sought after.

As useful as our atmosphere is for, well, keeping us all alive, there are certainly some downsides to being buried under a restless blanket of warm gas.

This research was published in Nature Communications.

 

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