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Astronomy

Astronomy

NASA is taking UFOs seriously.

What Is NASA?

The National Aeronautics and Space Administration (NASA) is a governmental organization responsible for the civil space program, aeronautics research, and space research in the United States. NASA was founded in 1958.

What Do We Mean By UFO?

Any apparent aerial phenomena that cannot be quickly recognized or explained is referred to as an unidentified flying object (UFO). Most UFOs are recognized as known objects or atmospheric phenomena after inquiry, however a small number remain unexplained.

NASA has joined the search for extraterrestrial craft.

The space agency unveiled a new research on Thursday that would enlist the help of prominent scientists to investigate unexplained aerial occurrences, a topic that has long piqued the public’s interest and has lately received high-level congressional attention.

The research will begin early this autumn and run about nine months, with the goal of discovering existing data, determining how to collect additional data in the future, and analyzing the findings to help NASA advance scientific understanding.

“NASA has answered the call to solve some of the most intriguing riddles we know of throughout the decades, and this is no different,” Daniel Evans, the NASA scientist in charge of the study, told reporters over the phone.

While NASA’s robots and rovers scan the solar system for ancient microbial fossils and astronomers search for “technosignatures” on faraway worlds for hints of intelligent civilizations, this is the first time the agency will look into strange events in Earth’s skies.

NASA is ideally positioned to not just debunk UFOs and enhance scientific knowledge, but also to develop measures to reduce the phenomenon, which is a crucial element of the agency’s mandate to protect aviation safety, according to NASA’s chief scientist, Thomas Zurbuchen.

The news comes at a time when UFO research, which was formerly viewed as a fringe area, is garnering increasing mainstream attention.

Last month, Congress convened a public hearing on UFOs, and a US intelligence assessment released last year listed 144 encounters as unexplainable. It didn’t rule out the possibility of an extraterrestrial origin.

Although NASA’s research would be separate from the Pentagon’s Airborne Object Identification and Management Synchronization Group, the space agency said in a statement that it “has coordinated broadly throughout the government over how to utilize the instruments of science.”

The scientific community is currently finding it difficult to form conclusions due to a scarcity of UFO sightings.

As a result, according to astronomer David Spergel, who will head the research, the group’s first duty will be to determine the scope of data available from consumers, government, organizations, and businesses.

NASA’s primary objective is to increase credibility in this field of study.

“Among our navy aviators and aviation community, there is a lot of stigma connected with UAP,” Evans said.

“One of the things we aim to achieve tangentially as part of this project, simply by talking about it in the open, is to help eliminate some of the stigma connected with it, and that will clearly result in more access to data, more reports, and more sightings,” she says.

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Astronomy

The best radiation shielding for Mars’ surface

Mars is reaching out to us. At least, that is the image one gets when looking at all of the planned and proposed trips to Mars during the next decade. With so many space organizations now launching missions to define their habitat, atmosphere, and geological history, crewed missions appear to be just around the horizon. Indeed, both NASA and China have stated that they want to send missions to Mars by the early 2030s, culminating in the construction of surface homes. Scientists are studying several methods of radiation shielding to safeguard astronaut health and safety, both in transit and on the surface of Mars. A team from the Blue Marble Space Institute of Science (BMSIS) has investigated how various materials may be utilized to create radiation-protective structures. Materials transported from Earth, as well as those gathered directly from the Martian environment, were included. This is consistent with the ISRU method, in which local resources are used to suit the demands of the astronaut crews and the mission.

Dionysios Gakis, a visiting scholar at BMSIS and a physics graduate of the University of Patras in Greece, conducted the research. Dr. Dimitra Atri, a senior research investigator at BMISIS, a physics professor at New York University Abu Dhabi’s Center for Space Science, and Gakis’ academic advisor, accompanied him. Acta Astronautica is considering publishing the manuscript that outlines their findings (“Modeling the efficiency of radiation shielding materials for astronaut safety on Mars”).

Because of its thin atmosphere and absence of a planetary magnetic field, Mars’ radiation environment is substantially more harmful than Earth’s. People in wealthy countries are exposed to 0.62 rads per year on average, but the surface of Mars receives around 24.45 rads per year—and considerably more when solar events occur.

“Galactic cosmic rays consist of charged particles that are a billion (or more) times more energetic than visible light. They can penetrate through shielding and cause irreversible damage to the human body. Additionally, solar storms can sometimes accelerate charged particles to very high energies (solar energetic particles), which can cause comparable damage,” Dr. Atri told Universe Today in an email.

Gakis and Dr. Atri looked into the qualities of several shielding materials that may be delivered to Mars or gathered in situ for their research. Aluminum, polyethylene, cyclohexane, polymethyl methacrylate, Mylar, and Kevlar were among the materials used, along with water, carbon fiber liquid hydrogen, and Martian regolith. According to Gakis, they evaluated each of these materials using the GEANT4 numerical model, which is a software suite that uses statistical Monte Carlo techniques to simulate particle passage through matter.

He explained, “We developed a computational model of Mars and analyzed the cosmic energy deposition within a hypothetical human phantom, simulating an astronaut.” “Before the radiation reached the astronaut, a barrier of material was placed to absorb some of it. In terms of radiation protection, the materials that allowed the least amount of energy to travel through the astronaut’s body proved to be the most effective.”

Their findings showed that hydrogen-rich materials (such as water ice) respond predictably to cosmic rays and are hence the best barrier against them. They also discovered that regolith has a medium response and, as a result, might be utilized for extra shielding, especially when paired with aluminum.

Gakis stated: “Although aluminum was not proven to be as efficient as other materials in decreasing radiation doses, it can still be useful, and we recommend mixing it with other materials. The behavior of Martian regolith is comparable, and it has the benefit of being an in-situ substance that does not need us to transport it from Earth.”

NASA and other space organizations are evaluating a variety of designs, materials, and technologies that may be used to build homes on the moon, Mars, and beyond. NASA and the Chinese National Space Agency (CNSA) are preparing crewed trips to Mars in the following decade, with flights launching every 26 months (beginning in 2033) and culminating with the construction of surface homes. According to Gakis and Dr. Atri’s research, these homes will most likely have an inner construction made of lightweight materials that can be carried cheaply from Earth.

Metal and carbon fiber, for example, may be made in-situ with aluminum extracted from Martian rock and carbon gathered from the planet’s atmosphere. Locally obtained water ice and regolith might then be used to form a protective superstructure, which robots would 3D print. Long-duration expeditions far beyond Earth will be possible with such homes, which might potentially serve as a stepping stone to permanent human colonies in space.

“One of the numerous concerns that humanity must overcome in order to effectively complete the human [exploration of] the red planet is radiation,” Gakis summarized. “We think our findings contribute to a better understanding of the harmful impacts of cosmic rays on the Martian environment and the development of appropriate mitigation techniques for future crewed missions to Mars.”

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Astronomy

The Magnetic Poles of the Earth are unlikely to flip

The appearance of a mystery location in the South Atlantic where the geomagnetic field strength is quickly deteriorating has sparked suspicion that Earth is on the verge of reversing its magnetic polarity. Recent research, though, reveals that the present alterations aren’t exceptional and that a reversal may not be in the cards after all. The research was published in the journal PNAS.

The magnetic field of the Earth works as an unseen screen against the life-threatening environment in space, as well as solar winds that would otherwise sweep the atmosphere away. However, the magnetic field is not stable, and polarity reversals occur at unpredictable intervals every 200,000 years on average. This implies the magnetic North and South poles are switched around.

The intensity of Earth’s magnetic field has declined by around 10% during the last 180 years. Simultaneously, in the South Atlantic, off the coast of South America, a region with an exceptionally weak magnetic field has grown. The South Atlantic Anomaly is a region where satellites have malfunctioned multiple times owing to exposure to highly charged particles from the sun. These events have sparked suspicion that we are on the verge of a polarity shift. However, according to a new study, this may not be the case. “We’ve studied changes in the Earth’s magnetic field over the last 9,000 years, and anomalies like the one in the South Atlantic are most likely periodic occurrences connected to comparable fluctuations in the Earth’s magnetic field strength,” says Andreas Nilsson, a geologist at Lund University.

The findings are based on examinations of charred archaeological artifacts, volcanic materials, and sediment drill cores, all of which include magnetic field information. Clay pots that have been cooked to above 580 degrees Celsius, hardened volcanic lava, and sediments deposited in lakes or the sea are examples of these. The items serve as time capsules, storing information about the previous magnetic field. The researchers were able to quantify these magnetizations and reconstruct the direction and strength of the magnetic field at specified locations and times using sophisticated instrumentation.

Andreas Nilsson explains, “We have created a novel modeling approach that integrates these indirect measurements from diverse time periods and locales into one worldwide reconstruction of the magnetic field over the last 9,000 years.”

Researchers can learn more about the fundamental mechanisms in the Earth’s core that create the magnetic field by looking at how it has evolved. By comparing actual and predicted fluctuations in the magnetic field, the new model may also be used to date archaeological and geological data. And, more reassuringly, it has led them to a conclusion about polarity reversal speculations:

“Based on parallels with the reconstructed anomalies, we anticipate that the South Atlantic Anomaly will most likely vanish within the next 300 years, and that Earth is not on the verge of a polarity shift,” Andreas Nilsson concludes.

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Astronomy

Three Chinese astronauts have arrived at Tiangong Space Station

What is a space station?

A space station is a form of space habitat that can support a human crew in orbit for an extended length of time. It doesn’t have any significant propulsion or landing systems. An artificial satellite is an orbiting station, often known as an orbital space station.

What is a space station used for?

The International Space Station (ISS) is a massive spaceship in Earth’s orbit. It serves as a residence for astronaut and cosmonaut crew. The space station also serves as a one-of-a-kind scientific laboratory.

Three Chinese astronauts landed at the country’s space station on Sunday, according to China’s space agency for human missions, marking the next step toward Beijing’s goal of becoming a major space power. According to official broadcaster CCTV, the three launched on a Long March-2F rocket from the Jiuquan launch complex in northwest China’s Gobi desert at 0244 GMT.

According to state-run CGTN, the team is entrusted with “completing in-orbit assembly and building of the space station,” as well as “commissioning of equipment” and performing scientific tests. The astronauts boarded the Tiangong station’s core module at 1250 GMT, according to the China Manned Space Agency (CMSA). According to CCTV, the voyage took roughly “seven hours of flight.”

By the end of the year, Tiangong, which means “heavenly palace,” should be completely operating.

China’s well-publicized space program has already resulted in the landing of a rover on Mars and the sending of probes to the Moon.

Chen Dong, a 43-year-old air force pilot, will lead the Shenzhou-14 crew, whose major task will be to connect the station’s two lab modules to the main body. Dong, along with fellow pilots Liu Yang and Cai Xuzhe, will be the second crew to spend six months on the Tiangong after the last crew returned to Earth in April after 183 days on the space station.

Tiangong’s core module was sent into orbit earlier this year and is intended to be operational for at least a decade.

The finished station will resemble the Soviet Mir station, which orbited Earth from the 1980s to 2001.

Space ambitions

The world’s second-largest economy has put billions of dollars into its military-run space program, hoping to have a permanently crewed space station by 2022 and eventually send humans to the Moon.

The country has made significant progress in catching up with the United States and Russia, whose astronauts and cosmonauts have decades of space exploration expertise.

However, under Chinese President Xi Jinping, the country’s preparations for its well publicized “space dream” have been accelerated. Beijing is also intending to develop a base on the Moon, and the country’s National Space Administration has stated that a crewed lunar mission will be launched by 2029.

Since 2011, when the US prevented NASA from working with China, China has been barred from participating in the International Space Station.

While China has stated that it does not intend to utilize its space station for global cooperation on the same scale as the International Space Station, it has stated that it is open to foreign collaboration.

The ISS is scheduled to be decommissioned in 2024, while NASA has said that it might be operational until 2030.

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Astronomy

What is our concept of the Blood Moon?

Although it sounds like something out of a gothic horror book, a “Blood Moon” is absolutely real, with the only link to blood being its hue. The Moon turns red around twice a year. The phenomenon occurs only during a total moon eclipse and is brought about by the same thing that keeps us alive: the Earth’s atmosphere.

In the year 2022, there will be four eclipses. We’ve already seen the first partial solar eclipse, and the first total lunar eclipse occurred last May 15-16. What is a Blood Moon, exactly?

What is a blood moon?

A Blood Moon is simply another name for a complete lunar eclipse, such as the one that occurred on May 15, 2022.

The Earth passes between the Sun and the Moon during a lunar eclipse, obscuring the Sun’s light. During this eclipse, the moon will be completely veiled. The Moon, on the other hand, isn’t fully dark. The Moon gradually darkens and changes color from dazzling white to orange-red as seen from Earth for a few hours.

Why is the moon red?

Sunsets and sunrises turn crimson, and so does the moon. The Earth’s atmosphere filters and scatters the sun’s light. The sky seems blue during the day because blue light is dispersed less than red light. However, when the sun is low on the horizon, the sky turns crimson.

This produces an unusual result. Despite the fact that the atmosphere is little in comparison to the size of the planet, the Earth’s shadow receives some of this diffuse light, which causes it to seem red. The Moon passes Earth’s shadow during a total lunar eclipse and appears crimson after it is entirely veiled.

It’s a beautiful sight to witness the Moon becoming darker as the shadow of our planet extends across its silvery surface, eventually turning a crimson color at the time of totality. Unlike solar eclipses, which last only a few minutes and are only visible in a tiny area of the earth, lunar eclipses can last up to two hours and are visible from everywhere on that specific night-side.

Why doesn’t the moon become red every month?

Blood moons are uncommon. Eclipses occur in long cycles and are determined by the Sun, Earth, and Moon’s positions. Because the lunar orbit is angled in relation to the Earth’s orbit around the Sun, eclipses can only occur when the three bodies are exactly aligned — in syzygy. In a calendar year, there are around four to seven eclipses, split between solar and lunar eclipses. Total lunar eclipses occur twice a year for a couple of years before a hiatus, whereas solar eclipses occur two to five times a year, with a total solar eclipse occurring every 18 months.

Many people believe that because the Earth’s shadow is red, we should see that coloration on the Moon when its near side changes phase. However, the shadow cast by the Moon during waning or waxing is not from the Earth. As certain lunar parts transition into sunlight and others into nighttime, the dark zone of the lunar phases is the Moon’s own shadow.

Why is the moon not red during a partial lunar eclipse?

The reason the Moon becomes red only near totality and not before is that the Moon reflects sunlight brightly, which drowns out the faint color of the Earth’s shadow.

The moment the Moon turns red is also unpredictable since it is heavily influenced by the atmosphere and its nebulosity at the time.

When is the next blood moon?

On May 15 and 16, the first total lunar eclipse happened. It could be seen in half of North America, the majority of Central America, and all of South America. Before daybreak, parts of Western Africa and Antarctica will witness the sight. The next one will be visible over the Pacific on November 8, 2022. We’ll have to wait until March 14, 2025, after that.

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Astronomy

NASA Reveals Details On The First Mission To Mars With Two Astronauts

NASA has formally begun planning the first crewed trips to Mars, which will include input from academics, international and industrial partners, as well as NASA’s own workforce. In a recent high-level workshop, NASA Deputy Administrator Pam Melroy remarked, “We will build this blueprint and rehearse it on the Moon with the objective of showing it on Mars.” 

NASA has established 50 objectives for which they are seeking assistance to get things started. They’ve also outlined the type of mission that may help them reach their goals.

The proposed trip will spend 30 days on the Martian surface, and NASA is seeking advice on the minimum capabilities required. The design includes a 25-ton pre-deployed cargo lander to guarantee the astronauts have the supplies they need when they arrive — transporting everything in one voyage with the crew was judged impracticable. A pre-landed crew assent vehicle is also necessary so NASA (and the astronauts) can be certain that they will be able to return to Earth.

NASA is attempting to avoid a recurrence of the Apollo missions, which saw people land on the Moon six times in a short period of time before disappearing for 50 years (and counting). “We want to get to a point where we can execute our missions on an annual basis,” said Jim Free, associate administrator. “So that we may maximize science and our system usage.” To get there, the plan calls for two crew members to stay in orbit while the other two travel to Mars’ surface. Another precursor is a robot mission that returns samples from the Martian surface. Aside from the amazing research that will be possible, it will provide NASA with a better notion of the circumstances in which crewed missions should be placed, as well as a practice, run for returning from Mars to the blue planet.

Even if it is repeated several times, a 30-day mission may feel short for so much work. The structure of the Terran and Martian orbits, however, means that if astronauts remain much longer, the return voyage will grow longer and more difficult, unless they stay for more than 500 days until the planets align again. The possibility of a 517-day expedition was examined, but the difficulties are evident.

“We’re performing a demonstration,” Free explained. “For actions in the remainder of the Solar System in the future.”

Dr. Kurt Spuds Vogel, Director of Space Architecture, stated that it has been more than 30 years since President Bush originally announced the “Moon to Mars” initiative. He described the subsequent period as a “roller-coaster ride” that has caused “widespread tension and concern” among scientists since money was promised or at least hinted at several times before being removed or postponed.

Despite its name, Artemis is partially an attempt to restart the Mars mission. The first stage of every mission has fewer challenges because of recent major advancements in launch technology. The chance that the Artemis mission will put astronauts on the Moon before the end of the decade (despite certain previously reported and anticipated delays) moves us closer.

Nonetheless, there are still several challenges in sending astronauts further than humans have ever gone and successfully returning them, which not all proponents admit. Submissions for those with ideas are due by May 31. “By the way, if we think your input is really fascinating, we could ask you to a workshop to talk about it,” Melroy stated. “If you’re interested, you may willingly provide your contact information.”

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Astronomy

Astronomers found the biggest molecule yet discovered in a planet-forming disc.

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, astronomers from the Netherlands’ Leiden Observatory discovered dimethyl ether in a planet-forming disc for the first time. This is the biggest molecule discovered in such a disc yet, with nine atoms. It is also a precursor to bigger organic compounds, which can result in the birth of life.

Dimethyl ether is a common chemical compound found in star-forming clouds, but it has never been seen in a planet-forming disc previously. The researchers also achieved a preliminary discovery of methyl formate, a complex chemical akin to dimethyl ether that may be used to generate even bigger organic compounds.

“It’s incredibly amazing to see these bigger molecules in discs for the first time. We believed for a long time that we wouldn’t be able to see them “Alice Booth, a researcher at Leiden Observatory, is one of the co-authors.

The molecules were discovered using ALMA, an observatory co-owned by the European Southern Observatory, in the planet-forming disc surrounding the young star IRS 48, also known as Oph-IRS 48. (ESO). IRS 48, situated 444 light-years away in the constellation Ophiuchus, has been the topic of multiple research due to the presence of an asymmetric, cashew-nut-shaped “dust trap” on its disc. This region, which most likely formed as a result of a newly formed planet or small companion star located between the star and the dust trap, retains a large number of millimeter-sized dust grains that can collide and grow into kilometer-sized objects such as comets, asteroids, and possibly planets.

This planet-forming disc surrounding the IRS 48 star, also known as Oph-IRS 48, is depicted in this artist’s rendition. This disc has an area in its southern hemisphere that collects millimeter-sized dust grains, which may collide and evolve into kilometer-sized objects like comets, asteroids, and possibly even planets. This “dust trap” is also an ice reservoir, with layers of ice containing complex molecules accumulating around the dust grains. The IRS 48 star’s heat can sublimate the ice into gas, releasing the trapped molecules and allowing them to be detected. The final animation depicts two of the compounds observed in the IRS 48 system: methanol and dimethyl ether, the latter of which is the biggest molecule yet identified in a planet-forming disc.

Many complex chemical compounds, such as dimethyl ether, are predicted to develop in star-forming clouds prior to the birth of the stars themselves. Atoms and basic molecules like carbon monoxide adhere to dust grains in these freezing conditions, generating an ice coating and performing chemical processes that result in more complex molecules. Researchers have revealed that the IRS 48 disc’s dust trap is actually an ice reservoir, including dust grains wrapped in complex molecule-rich ice. ALMA has recently discovered evidence of the dimethyl ether molecule in this region of the disc: when heating from IRS 48 sublimates the ice into gas, the trapped molecules inherited from the cold clouds become free and observable.

“What makes this more intriguing is that we now know these more complex chemicals are accessible to feed planets developing in the disc,” Booth says. “This was previously unknown since, in most settings, these molecules are concealed under the ice.”

The finding of dimethyl ether hints that many additional complex compounds seen in star-forming regions may also be hidden atop frozen structures in planet-forming discs. These compounds are the antecedents of prebiotic chemicals like amino acids and carbohydrates, which are some of the fundamental building blocks of life.

Researchers can acquire a better grasp of how prebiotic chemicals end up on worlds like ours by examining their origin and development. “We are overjoyed that we can now begin to track the complete course of these complicated chemicals from star-forming clouds to planet-forming discs and comets. With further data, we should be able to get a little closer to understanding the origins of prebiotic chemicals in our own Solar System “Nienke van der Marel, a Leiden Observatory researcher who also took part in the study, agrees.

Future investigations of IRS 48 using ESO’s Extremely Large Telescope (ELT), which is now being built in Chile and is scheduled to begin operations later this decade, will allow the researchers to explore the chemistry of the disc’s most inner regions, where planets like Earth may be forming.

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Astronomy

Does Planet 9 Exist or Not?

There are eight planets in our solar system. Pluto was reclassified as a dwarf planet in 2006, joining Eris, Sedna, Quaoar, Ceres, and perhaps many more tiny worlds in the solar system. These are roughly described as bodies that circle the sun but are not large enough to remove material from their environs by gravitational dominance. However, astronomers wonder whether there isn’t a previously undiscovered ninth planet hiding in the solar system’s beyond reaches, maybe in the massive Oort cloud of debris that begins hundreds of astronomical units from the sun and stretches outward.

Recent data suggest that the orbital characteristics of several tiny things beyond Neptune appear to behave as if they had been impacted by the gravity of a big object in the outer solar system, reinforcing the idea that there may be a ninth massive planet in the outer solar system. Despite observational biases and statistical limitations, these findings have reignited interest in the possibility of an extraterrestrial presence.

Planet 9 would be roughly 5 to 10 Earth masses in size and orbit the sun at a distance of 400 to 800 au, according to estimations. Because of its faintness, a planet at this distance would be exceedingly difficult to discover in regular optical sky searches, even with telescopes like PanSTARRS and LSST. Most solar system objects were discovered using reflected sunlight, but the sunlight they receive diminishes due to the inverse square law for electromagnetic radiation, which states that measured light intensity is inversely proportional to the distance squared from the source of radiation; additionally, the reflected portion travels back to Earth’s telescopes and diminishes by a similar factor.

Although these objects are cold, they may release more infrared radiation than the optical light they reflect at the furthest reaches of the solar system, and astronomers have searched for them in the past using infrared surveys such as the Wide-field Infrared Explorer, but without success.

Benjamin Schmitt, a CfA astronomer, was part of a big team that used Chile’s 6-meter Atacama Cosmology Telescope (ACT) to look for Planet 9 at millimeter wavelengths. Despite the fact that ACT was created to research the cosmic microwave background radiation, its high angular resolution and sensitivity make it ideal for this sort of search.

Over a six-year period, the astronomers scanned around 87 percent of the sky visible from the Southern Hemisphere, then processed the millimeter pictures using a number of techniques, including binning and stacking approaches that may reveal faint sources but at the cost of losing positional information. They uncovered a lot of potential sources, but none of them could be confirmed, and there were no statistically significant findings.

The scientists, on the other hand, were able to eliminate with 95 percent certainty a planet 9 with the above-estimated attributes inside the investigated area, which is consistent with earlier null searches for Planet 9. The results only cover around 10 to 20% of the possibilities, but other sensitive millimeter facilities are coming up and should be able to finish the search for Planet 9 as predicted.

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Astronomy

Astronomers have discovered the biggest radio galaxy yet discovered.

By chance, a team lead by Dutch Ph.D. student Martijn Oei discovered a radio galaxy at least 16 million light-years long. The pair of plasma plumes is the galaxy’s greatest structure to date. The discovery refutes several long-held assumptions concerning the evolution of radio galaxies.

A supermassive black hole lurks in the heart of many galaxies, slowing the production of new stars and so having a large impact on the galaxy’s overall lifetime. This can result in chaotic scenes: the black hole can generate two jet streams, which hurl the building material for young stars out of the galaxy at almost the speed of light. The stardust warms up so rapidly during this violent process that it melts into plasma and glows in radio light. The light was captured by an international team of researchers from Leiden, Hertfordshire, Oxford, and Paris using the pan-European LOFAR telescope, whose epicenter is in a marshy Dutch radio dark’ nature reserve where your smartphone intentionally loses service.

Record length

The image of the two plasma plumes is noteworthy because scientists have never seen a structure this large created by a single galaxy before. The research demonstrates that the sphere of the effect of some galaxies extends far beyond their immediate surroundings. How far are we talking? That is difficult to ascertain. Astronomical images are acquired from a single point of view (Earth) and hence lack depth. As a result, scientists can only measure a portion of the radio galaxy’s length, providing a conservative estimate of the whole length. Even still, the lowest bound of more than 16 million light-years is enormous, similar to a hundred Milky Ways in a row.

The naked radio eye can see it

Because Earth does not have a unique position in the cosmos, it was never anticipated that such a massive cosmic structure would be found in our own backyard. And it’s true: the radio behemoth is three billion light-years away. Despite the incredible distance, the mammoth loom was as huge as the moon in the sky, indicating that the building had to be a record length. Because the plumes are quite weak, the radio eyes of the LOFAR observatory only just detected the monster. The scientists were able to identify the mammoth by reprocessing a batch of old photographs in such a manner that minor patterns shone out.

The gigantic edifice was dubbed Alcyoneus by the researchers after Ouranos, the Greek primal deity of the sky. This legendary Alcyoneus was a giant who battled Heracles and other Olympians for control of the cosmos. A sculpture of this Alcyoneus may be seen at Berlin’s world-famous Pergamon Altar.

Ghostly dance

The plumes of Alcyoneus may give information on the usually mysterious strands of the Cosmic Web. The Cosmic Web is another name for the modern, grown-up cosmos, which resembles a network of threads and nodes known as filaments and clusters, respectively. The galaxies in filaments and clusters are readily visible, however finding the medium between galaxies has only been achieved in clusters (with a few outliers). Could Alcyoneus make a difference?

Because Alcyoneus, like the Milky Way, lives in a filament, its plumes experience a headwind as they move across the medium. This gently alters the plume’s path and shape: they do a leisurely dance with an invisible companion. Scientists have argued for many years that the shapes and pressures of radio galaxies’ plumes may be related to filament features, but never before have they seen a case where that relationship is as feasible as with Alcyoneus. Alcyoneus’ plumes are so large and rarefied that the surrounding medium may readily mold them.

Black holes are cosmic stalwarts

Because the thermal pressure of the medium in filaments and clusters compensates for the attraction pull of gravity, the Cosmic Web maintains its shape. The shimmering stardust that jet streams expel from galaxies has been proven to keep the Web toasty for the last two millennia. In this approach, galaxies’ center black holes help to maintain the universe’s large-scale structure. This is especially significant given how tiny black holes are in comparison to filaments and clusters. It’s as if a marble-sized object controls the Earth’s temperature.

Mysterious origin

For the time being, it is unknown what gave Alcyoneus his record length. The researchers originally considered a giant black hole, a large stellar population (and hence a lot of stardust), or extremely intense jet streams. Surprisingly, when compared to its smaller sisters and brothers, Alcyoneus appears to be below average in all of these areas. The researchers will now study if the surroundings of radio galaxies may instead explain the rise of giants in the future.

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