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How Satellites Can Utilize Magnetic Fields to Prevent Collisions

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Innovative Control Method for Satellites in Space

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Utilizing magnetic fields to maneuver satellites could significantly enhance the longevity of space exploration missions and reduce the risk of collisions between spacecraft.

Currently, most space missions and artificial satellites depend on propellant for movement in space, which limits their operational lifetimes due to fuel depletion. An innovative alternative, known as electromagnetic formation flight (EMFF), employs renewable energy sources like solar panels to power onboard electromagnetic coils. These coils generate magnetic fields that can theoretically steer spacecraft through interactions with similar fields from adjacent satellites.

However, researchers have faced challenges with EMFF due to a phenomenon called electromagnetic coupling. The magnetic field from one satellite affects not just nearby satellites but all satellites in proximity, complicating coordinated movement among multiple objects.

A research team at the University of Kentucky has proposed a promising solution through a method called alternating magnetic field forcing (AMFF).

This technique enables two satellites to communicate and control each other’s trajectories without disrupting a third satellite. This is achieved by utilizing distinct interaction frequencies, allowing two satellites to coordinate on one frequency while maintaining communication with others on different frequencies.

The AMFF concept has been successfully tested on Earth instead of in space. The three satellites were positioned on specialized linear rails employing high-pressure air to create a low-friction environment. With the integrated laser ranging module, the satellites achieved precise travel distances and effective interactions as defined by the researchers.

The project team did not respond to interview requests. However, Alvar Saenz Otero, a researcher at the University of Washington, noted that this paper represents a significant advancement in a long-standing research area. “The complexity of a formation flight system increases significantly when transitioning from two to three satellites,” he explains.

Yet, Otero expresses skepticism about the immediate application of this technology for low-Earth orbit satellites, such as massive constellations like Starlink. “Our work on EMFF has primarily focused on deep space operations,” he adds.

Earth’s atmosphere can impact the frequencies utilized for EMFF or AMFF, introducing interference that complicates satellite control, he notes.

While it is currently feasible for three units to fly together and utilize magnetic fields for navigation, scaling this approach to manage thousands of satellites poses a formidable challenge. “This is not applicable at the constellation level,” remarks Ray Sedwick from the University of Maryland.

“Employing superconducting magnetic coils significantly extends the operational range of EMFF, but numerous technical challenges remain,” Sedwick explains, indicating that large-scale magnetic motion might still be on the horizon.

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Source: www.newscientist.com

ALMA Observes Spiral Gas Streamers Controlled by Magnetic Fields in Star-Forming Areas

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This stream of gas transports material from the clouds surrounding the star-forming area within Perseus directly into an emerging binary star system known as SVS 13A.

Artist’s impression of the SVS 13A system. Image credit: NSF/AUI/NSF’s NRAO/P.Vosteen.

Stars are formed from clouds of gas and dust, and recent observations indicate that the process of star formation is far more dynamic than previously understood.

New findings from the Atacama Large Millimeter/Submillimeter Array (ALMA) reveal both dust and molecules swirling around the SVS 13A system. This data shows how the magnetic field not only permeates these stellar nurseries but actively directs the flow of matter, offering a preferred path for gas to accumulate in the disk where new stars and planets arise.

“Visualize a garden hose, but instead of water, it smoothly channels materials for star formation through intricate pathways carved by unseen forces,” explains Dr. Paulo Cortes, an astronomer at the NSF National Radio Astronomy Observatory and the joint ALMA telescope.

“This perspective from ALMA observations presents channels of gas known as subalfvénic streamers, regulated by spiral magnetic field lines.”

“This new data provides an insightful glimpse into the star formation process.”

“These streamers illustrate how magnetic fields can influence star formation by managing material influx, akin to a private highway facilitating car travel.”

ALMA’s images and findings uncover two spiral arms of dust encircling the star, with gas streams closely mirroring the same trajectory.

This remarkable configuration implies that the gas within the streamer is traversing at a slower pace than previously believed, reinforcing the concept of a magnetized channel rather than a chaotic, collapsing cloud.

The presence of such streamers, linking clouds to disks and supplying them with material in a managed fashion, indicates that both gravity and magnetism are crucial in the formation of stars and the shaping of potential planetary bodies around them.

This groundbreaking result signifies the first instance where astronomers have directly mapped both a streamer and its associated magnetic field in a single observation.

“Subalfvenic streamers indicate a fresh role for magnetic fields amidst gravitational dominance, acting as ‘guides’ to assist the descent of material from the outer envelope to the disk,” the astronomers remarked.

Upcoming findings are detailed in a paper in the Astrophysics Journal Letter.

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PC Cortez et al. 2025. First results from ALPPS: SVS 13A subalfvenic streamer. APJL 992, L31; doi: 10.3847/2041-8213/ae0c04

Source: www.sci.news

How Do Small Galaxies Acquire Their Magnetic Fields? – Sciworthy

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Among the four fundamental forces in the universe, gravity often comes to mind when considering cosmic phenomena. This is quite logical, as gravity operates over vast distances, exerting its influence on massive objects, making it the most significant and far-reaching force. However, another essential force, known as electromagnetism, also plays a critical role in the study of space.

To begin with, all light is made up of electromagnetic radiation, which consists of oscillating electric and magnetic fields. This includes everything from radio waves to visible light and X-rays. Similar to Earth and the Sun, many celestial bodies are enveloped in magnetic fields. The Earth’s magnetic field serves as a shield against harmful radiation, while the solar magnetic field repels it. The generation of a magnetic field requires the movement of charged particles, such as protons and electrons. Consequently, a variety of objects, including entire galaxies, possess magnetic fields!

Researchers are aware that galaxies have magnetic fields, but it remains uncertain how various galaxies develop different magnetic intensities or how these fields influence their evolution over time. This investigation is further complicated by the fact that galaxies often exist in clusters. For instance, the Milky Way is surrounded by smaller galaxies known as satellites, which exert gravitational pull on each other and interfere with each other’s magnetic fields.

The research team explored how diverse environments in smaller galaxies affected the strength of their magnetic fields. They approached this by simulating the motion of materials within the galaxy as if they were liquids filled with striped particles. Two sets of simulations were conducted, the second of which also included the effects of high-energy particles known as cosmic rays.

In total, they simulated magnetic fields across 13 distinct scenarios, ranging from isolated galaxies with masses 10 billion times that of the Sun to those 10 trillion times greater, accompanied by up to 33 satellites. Each simulation commenced with galaxies exhibiting a magnetic field strength of 10-14 Gauss (g). For context, Earth’s magnetic field strength is about 0.3-0.6 g. The scenarios were evolved over 12 billion simulation years, allowing galaxies to interact, traverse space, and form stars, subsequently tracking the magnetic field strength in smaller galaxies.

Throughout the simulated timeline, the magnetic fields of all galaxies strengthened as star formation progressed. The birth of stars stirs the galactic matter, enhancing magnetic field strength and producing cosmic rays. Most galaxies concluded with magnetic fields ranging from 10-7 to 10-6 G, with larger galaxies typically achieving stronger fields. Interestingly, the researchers found that small galaxies passing in close proximity to larger companions exhibited stronger magnetic fields than equivalent isolated galaxies.

They monitored satellite galaxies over a series of simulations and discovered that, on average, magnetic field strength increased by 2-8 times as these galaxies approached their host. In extreme cases, the satellite’s magnetic field intensified by up to 15 times after nearing the host. In contrast, satellite galaxies that were more distant or had not yet approached their host did not show such significant increases in magnetic field strength.

The researchers interpret their findings to suggest that the more turbulent the interstellar medium (ISM) within a galaxy, the greater the strength of its magnetic field. Orbiting near a host galaxy tends to disturb the ISM of the satellite galaxy, rendering it more magnetic than a solitary small galaxy. Approaching a massive galaxy compresses the satellite, exposing it to magnetizing materials, and both interactions contribute to amplifying the magnetic field strength.

The team recommends that future studies utilize these results to inform radio and gamma-ray observations of galaxies, as these two segments of the electromagnetic spectrum can provide astronomers insights into the magnetic field properties of celestial bodies. They also caution that astronomers conducting simulations of isolated galaxies might yield skewed results since such a scenario does not accurately reflect the reality in which many galaxies are in proximity to companions.

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Source: sciworthy.com

Ancient Mayan ball fields reveal presence of psychoactive and ceremonial plants, say researchers

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A research team led by University of Cincinnati archaeologists has found evidence of an assemblage of four species of ceremonial plants beneath the endfield of a late Preclassic ball field at the Helena complex in Mexico’s ancient Mayan city of Yaxnoca. Plants included Ipomoea corymbosa (xtabentun in Mayan), Capsicum sp. (chili pepper or ic in Mayan), Hampea Trilobata (Joel), and Oxandra lanceolata (Chilkahuit). Two of these plants, jor and Cirkawit, are involved in the production of ritually related crafts, while chili pepper and Stabentun are associated with divination rituals. Extaventun (known to the Aztecs as oloruqui) produces a highly effective hallucinogenic compound.

Map of the Helena complex showing excavation locations in relation to the baseball field structures (Structures H-4 to H-7). Image credit: Lenz other., doi: 10.1371/journal.pone.0301497.

The ancient Mayans played several ball games, including pokatok, which had rules similar to soccer and basketball. Players tried to pass the ball through rings and hoops on the wall.

“The ancient Mayans likely made ceremonial offerings during the construction of their ball courts,” said University of Cincinnati professor David Lentz.

“When they built a new building, they asked for God’s goodness to protect the people living there.”

“Some people call this a soul-entering ritual to obtain blessings from the gods and appease them.”

From 2016 to 2022, Professor Lentz and colleagues worked in the ancient Mayan city of Yaxnoca, in the state of Campeche, about 14.5 kilometers (9 miles) north of the Guatemalan border.

They discovered 2,000-year-old Mayan ceremonial deposits beneath the early piazza floor of the civil ceremonial platform on which the ball court was built in Yaxnoca’s Helena complex.

“Just like with baseball stadiums, when a building was expanded or reused, the ancient Mayans made offerings to bless the site,” said Nicholas Dunning, a professor emeritus at the University of Cincinnati.

“Archaeologists sometimes find ceramics and jewelry among these offerings, along with culturally significant plants.”

“We’ve known for years from ethnohistorical sources that the Maya also used perishable materials in these offerings, but finding them archaeologically is nearly impossible and That’s what makes this discovery using eDNA so special.”

“In tropical climates, ancient plant remains are rarely found and quickly decompose.”

However, using environmental DNA, scientists were able to identify several types known for their ritual significance.

They found evidence of a morning glory called stabentun, known for its hallucinogenic properties, lancewood, chili pepper, and jowl, whose leaves were used to wrap ritual offerings.

“It’s significant that we found evidence that these plants exist together in the same small sediment sample,” said Dr. Eric Tepe, a botanist at the University of Cincinnati.

“The fact that these four plants, known to be culturally important to the Maya, were found in concentrated samples indicates that they were intentionally and purposefully collected under this platform. I think that says a lot.”

“Interpreting a botanical collection through the opaque lens of 2,000 years of prehistory is a challenge, but this discovery helps further deepen the story of this sophisticated culture,” Professor Lenz said.

The ancient Mayans devised water filtration systems and adopted forest practices with conservation in mind.

However, they were powerless against years of drought and are thought to have cleared vast areas of forest for agriculture.

“We see the yin and yang of human existence in the ancient Maya. To me, that’s why they’re so fascinating,” Professor Lentz said.

of findings It was published in the magazine PLoS ONE.

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DL Lenz other. 2024. Psychotropic drugs and other ceremonial plants unearthed from a 2,000-year-old Mayan ritual deposit at Yaxnoca, Mexico. PLoS ONE 19 (4): e0301497; doi: 10.1371/journal.pone.0301497

Source: www.sci.news