Tag Archives: activity

Webb discovers evidence of hydrothermal activity within Ellis and Makemake

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Methane ice of unknown origin exists on the surfaces of the icy dwarf planets Eris and Makemake. Analysis of data from the NASA/ESA/CSA James Webb Space Telescope shows that Ellis and Makemake have rocky cores that have undergone significant radiation heating and are still hot/hot enough to produce methane. There is a possibility.

grain other. Researchers have discovered evidence of hydrothermal or metamorphic activity deep within the icy dwarf planets Eris and Makemake. Image courtesy of Southwest Research Institute.

“We're seeing some interesting signs of a hot period in a cool place,” said Dr. Christopher Grein, a planetary researcher at the Southwest Research Institute.

“I approached this project thinking that because the cold surfaces of large Kuiper Belt Objects (KBOs) can store volatile materials like methane, they should have ancient surfaces with material inherited from the proto-solar nebula. I participated.”

“Instead, Webb had a surprise for us! We found evidence of a thermal process producing methane from inside Ellis and Makemake.”

Dr. Grein and his colleagues used the Webb to observe isotope molecules on the surfaces of Ellis and Makemake for the first time.

These so-called isotopologues are molecules containing atoms with different numbers of neutrons. These provide data that helps us understand the evolution of planets.

The astronomers measured the composition of the dwarf planet's surface, specifically the ratio of deuterium (deuterium, D) to hydrogen (H) in methane.

Deuterium is thought to have formed in the Big Bang, and hydrogen is the most abundant atomic nucleus in the universe.

The D/H ratio of planetary bodies provides information about the origin, geological history, and formation routes of hydrogen-containing compounds.

“The moderate D/H ratio observed by Mr. Webb discredits the existence of primordial methane on the ancient Earth's surface. The D/H ratio of primordial methane would be much higher,” Dr. Grein said. I did.

“Instead, the D/H ratio indicates the geochemical origin of the methane produced deep inside. The D/H ratio is like a window. You can use it to look into the subsurface.”

“Our data suggest that temperatures in the cores of these world rocks could increase and methane could be cooked.”

“Nitrogen molecule (N2) may be generated as well, and this has also been confirmed in Eris. ”

“Hot cores may also indicate a potential source of liquid water beneath the surface of the ice.”

“If Eris and Makemake harbored, or perhaps still harbor, warm or hot geochemistry in their rocky cores, then the surface of these planets is probably geologically recent, due to cryogenic volcanic activity. could be supplied with methane,” said Dr. Will Grundy. Astronomer at Lowell Observatory.

“We discovered the carbon isotope ratio (13C/12C) suggests that the surface has been resurfaced relatively recently. ”

“Following NASA's New Horizons flyby of the Pluto system, and with this discovery, the Kuiper Belt turns out to be much more alive than we imagined in terms of hosting a dynamic world.” said Dr. Grein.

“It's not too early to start thinking about sending spacecraft to fly close to other of these objects to put Webb's data into geological context. I'm sure we'll see the surprises that lie ahead. I think you’ll be surprised!”

of study It was published in the magazine Icarus.

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Christopher R. Grein other. 2024. Moderate D/H ratios in the Ellis and Makemake methane ices indicate evidence of hydrothermal or metamorphic processes in the interior: a geochemical analysis. Icarus 412: 115999; doi: 10.1016/j.icarus.2024.115999

Source: www.sci.news

New research indicates that early Mars experienced both tectonic and volcanic activity.

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Mars' relatively well-preserved ancient crust provides a natural window into early planetary evolution not visible on Earth. Mars has generally been thought to be a monolithic basaltic planet, but recent evidence suggests that magmatic evolution leading to a felsic crust may have occurred sporadically. A new study shows multiple lines of evidence for diverse volcanic activity and complex volcanic tectonics in Mars' southern highlands in and around the Eridanian basin 3.5 to 4 billion years ago.

Topographic map of the Eridanian region of Mars. The volcanic structure described by Michalski et al. Classified by morphology and morphometrics. Image credit: Michalski other., doi: 10.1038/s41550-023-02191-7.

In contrast to Earth, Mars today has little volcanic or tectonic activity.

Additionally, nearly half of Earth's surface is more than 3.5 billion years old, and since then it has undergone extensive tectonic recycling (a phenomenon typically caused by Earth-like tectonic movements, in which surface material is recycled into the mantle). This shows that there is no such phenomenon.

Recent discoveries suggest that this is not always the case, but geological activity during the first billions of years after Mars' formation is still unknown.

“Geological exploration of other rocky planets provides clues to early crustal evolution and volcanic tectonic processes,” said Dr. Joseph Michalski of the University of Hong Kong. “This is an example of an equivalent Earth system with a changing composition.”

“Looking through the lens of different gravitational fields, bulk planetary compositions, and heat flows allows us to test models of crustal resurfacing and discover the steps that led to plate tectonics and other forms of crustal recycling.” It will be possible to do so.”

“Mars represents a particularly valuable piece of the puzzle in this regard.”

The authors studied the morphology and mineralogy of the Eridanian region in Mars' southern hemisphere.

They analyzed remote sensing data from a variety of orbiting satellites, including NASA's Mars Global Surveyor, Mars Odyssey, and Mars Reconnaissance Orbiter.

The Eridanian region contains the most powerful crustal remains of Mars' ancient magnetic field and various traces of volcanic activity.

The researchers identified 63 examples of four different types of volcanoes (volcanic domes, stratovolcanoes, pyroclastic shields, and caldera complexes), and there are likely hundreds more in the Eridanian region alone. , these are probably the remnants of a period of active geological activity about 3.5 billion years ago.

This set of observations is consistent with the existence of early Martian tectonic cycles driven by vertical tectonics, a type of tectonic process precursor to full plate tectonics on Earth.

Such diverse volcanic structures may be more widespread on ancient Mars than previously thought.

“The observed remnants of this activity may be the closest analog on Earth to the proposed hydrothermal origin of life scenario for Earth,” the scientists said.

Their paper Published in an online journal today natural astronomy.

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JR Michalski other. Diverse volcanic activity and crustal circulation on early Mars. Nat Astron, published online on February 12, 2024. doi: 10.1038/s41550-023-02191-7

Source: www.sci.news

Solar Activity Brings NASA’s NEOWISE 10-Year Mission to a Close

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NEOWISE Mission

This artist’s concept shows the Wide Field Infrared Surveyor (WISE) spacecraft orbiting the Earth. The NEOWISE mission will find and characterize asteroids.
Credit: NASA/JPL-California Institute of Technology

Infrared space telescopes searching for asteroids and comets have collected vast amounts of observations, but are now at the mercy of the sun, which is accelerating their demise.

NASA’s Neowise It’s been a busy 10 years. Since its resumed mission began on December 13, 2013, the space telescope has discovered once-in-a-lifetime comets, observed more than 3,000 near-Earth objects, strengthened international planetary defense strategies, and It has helped other NASA missions rendezvous with distant space. asteroid. This is just a partial list of achievements.

But all good things must come to an end. Solar activity is pushing NEOWISE (short for Near-Earth Object Wide-field Infrared Survey Explorer) out of orbit. By early 2025, the spacecraft is expected to have fallen far enough into Earth’s atmosphere that it will become unusable. Eventually it will re-enter the atmosphere and burn up completely.

Approximately every 11 years, the Sun goes through a cycle of increasing activity, peaking during a period called solar maximum. Explosive events such as solar flares and coronal mass ejections will become more frequent, heating the Earth’s atmosphere and causing it to expand. Atmospheric gases increase the drag on satellites as they orbit the Earth, slowing them down. Now, as the Sun approaches its next maximum, NEOWISE will no longer be able to maintain its orbit above the atmosphere.

Comet C/2020 F3 NEOWISE is a composite of several heat-sensitive infrared images taken by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission on March 27, 2020. Appears as a blurry red dot.
Credit: NASA/JPL-California Institute of Technology

“The mission has been planning for this day for a long time. After several years of lull, the sun is waking up again,” said NEOWISE co-principal investigator and researcher at the California Institute of Technology in Pasadena, California. said Joseph Masiello, a scientist with the organization IPAC. “With us at the mercy of solar activity and no means of staying in orbit, NEOWISE is now slowly spiraling back to Earth.”

wise beginnings

The past decade has meant a second life for the spacecraft. Managed by NASA’s Jet Propulsion Laboratory in Southern California, NEOWISE is part of another mission launched in 2009, the Wide-Field Infrared Surveyor (wise). Data from WISE and NEOWISE is used to study distant galaxies, cold stars, and explosions. white dwarf Stars, gas-emitting comets, near-Earth asteroids, etc.

In 2010, WISE achieved its scientific goal of conducting an all-sky infrared survey with far greater sensitivity than previous surveys. WISE mission also discovered tens of millions of actively feeding supermassive black holes across the sky.through disc detective In this project, citizen scientists used WISE data to find circumstellar disks, which are clouds of gas, dust, and debris that rotate around stars.

Infrared wavelengths, which are invisible to the naked eye, are emitted by warm objects. To ensure that the heat generated by WISE itself does not interfere with observations in infrared wavelengths, the spacecraft relied on cryogenic coolant. NASA put the spacecraft into hibernation in February 2011 after it ran out of coolant and WISE mapped the sky twice.

Without the coolant, space telescopes could no longer observe the coldest objects in the universe, but they could still see near-Earth asteroids and comets heated by the sun. So NASA restarted the spacecraft in 2013 with a more specialized role in mind. The goal is to support planetary defense efforts by investigating and studying objects that may wander into Earth’s orbit and pose a potential collision hazard.

In addition to relying on missions to explore these objects, astronomers use that data to understand the object’s size, albedo, or how much sunlight its surface reflects, and the composition of its structure. You can also collect clues about the minerals and rocks you find.

“NEOWISE demonstrates the importance of deploying infrared space exploration telescopes as part of NASA’s planetary defense strategy while also monitoring objects in our solar system and beyond,” said lead researcher Amy, from the University of Arizona in Tucson. Mainzer said. .

Mainzer also leads NASA’s future plans. NEO surveyor, built on the NEOWISE tradition. The next generation of infrared space telescopes will search for celestial objects close to the Earth, such as dark asteroids and comets that do not reflect much visible light, or objects that approach the Earth from the direction of the sun. Sun. The launch is scheduled for 2027. JPL-Managed missions will also explore objects known as Earth Trojans – asteroids that lead or follow our planet’s orbit. The first one is wise discovery In 2011.

Comet NEOWISE and beyond

Since becoming NEOWISE, the mission has scanned the entire sky more than 20 times and made 1.45 million infrared measurements on more than 44,000 Solar System objects. This includes over 3,000 near-Earth objects, 215 of which were discovered by his NEOWISE. Data from the mission helped refine the orbits of these objects, while also measuring their sizes.

Its strength is in revealing the characteristics of asteroids near the Earth. In 2021, NEOWISE became a key component of an international planetary defense exercise focused on the dangerous asteroid Apophis.

The mission also discovered 25 comets, including long-period comet C/2020 F3 (NEOWISE). The comet was a dazzling object visible in the Northern Hemisphere for several weeks in 2020, making it the first comet to be visible to the naked eye since 2007, when Comet McNaught was primarily visible in the Southern Hemisphere.

Future researchers will use WISE in 2010, long after observations were made to characterize the asteroid Dinkinesh, in support of NASA’s Lucy mission before the October 2023 encounter. Just as we used the data, we will continue to rely on the vast archive of NEOWISE observations to make new discoveries.

“This is a bittersweet moment. We are sad to see this pioneering mission come to an end, but we know there are even more treasures hidden in the survey data,” Masiello said. “NEOWISE has a vast archive that covers a very long period of time and will inevitably advance the science of the infrared universe long after the spacecraft leaves.”

Mission details
NEOWISE and NEO Surveyor are part of NASA’s Planetary Defense Coordination Office (PDCO) at NASA Headquarters in Washington. The NASA Authorization Act of 2005 directs NASA to discover and characterize at least 90% of near-Earth objects larger than 140 meters (460 feet) in diameter that come within 30 million miles (48 million kilometers) of Earth’s orbit. did. An object of this size could cause significant damage to the region, and it would be even worse if it crashed into Earth.
JPL manages and operates PDCO’s NEOWISE mission within the Science Mission Directorate. The Astrodynamics Laboratory in Logan, Utah, built the scientific instrument. Ball Aerospace & Technologies of Boulder, Colorado, built the spacecraft. Scientific data processing will take place at IPAC at the California Institute of Technology. Caltech manages JPL for NASA.



Source: scitechdaily.com

Climactic launches inaugural fund as partners shift focus to upcoming surge in climate technology M&A activity

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A few years Earlier, when the pandemic was still in full swing, Raj Kapoor and Josh Felser started investing in climate change technology startups.they called their operation climax, and initially placed bets using their own money. Although we are both experienced founders, managers, and investors, this is our first time focusing on this specific sector and we started by testing the waters.

The company announced today that it has closed a $65 million founding fund and used it to support founders launching a climate technology software company.

Mr. Kapur and Mr. Felser both have long histories as investors, with Mr. Felser co-founding Freestyle Capital and Mr. Kapur spending seven years as a managing director at Mayfield Funds. They also founded and sold their own software startup.

It’s a little surprising that it took this long for the two to work together. Their resumes are strikingly similar. Felser said that in 1997 he founded Spinner (sold to AOL) and in 2004 he founded Crackle (sold to Sony). He also launched the #Climate nonprofit in 2014 and created a public-private coronavirus task force during the pandemic. Mr. Kapur previously served as chief strategy officer at Lyft, and before that he founded Snapfish (acquired by HP) and FitMob (acquired by ClassPass). He also launched a nonprofit climate social app in 2007.

Those experiences, combined with a growing concern about the state of the Earth’s climate, led the two to form Climactic.

“If we can get the top 50 supply chains to meet their net-zero goals, rather than just pay lip service, we’ll have the biggest impact,” Kapur told TechCrunch+. “To get there, we think the low-hanging fruit is software, because there are a lot of efficiencies to be gained.”

Source: techcrunch.com

“Unconscious Brain Activity and Epileptic Seizures: The Role of Sleep Brain Waves”

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A new study has found that the slow brain waves typical of sleep occur in epilepsy patients when they are awake, helping to prevent the brain from becoming more excited. These waves reduce epileptic activity while negatively impacting memory, suggesting a potential new therapeutic approach for epilepsy.

UCL researchers have found that slow brain waves commonly seen during sleep occur in epilepsy patients while they are awake, preventing seizures but affecting memory, suggesting a new potential treatment for epilepsy. are doing.
A new study led by researchers at University College London (UCL) has found that slow waves, which normally occur only in the brain during sleep, also occur when epilepsy patients are awake, and show that slow waves, which are associated with epilepsy symptoms, can also occur in the brain during sleep. It was found that there is a possibility of preventing increased excitement.

Methodology and findings

The study was published today (November 30) in the journal nature communications The National Institute for Health Research (NIHR) UCLH Biomedical Research Center also took part in conducting electroencephalogram (EEG) scans from electrodes in the brains of 25 patients with focal epilepsy (a type of epilepsy characterized by seizures originating from specific parts of the brain). was inspected. brain), they performed an associative memory task.
Electrodes were placed in the patient’s brain to localize abnormal activity and inform surgical treatment.
During the task, participants were presented with 27 pairs of images that remained on the screen for 6 seconds. The images are divided into nine groups of three, and each group contains photos of people, places, and objects. In each case, participants had to remember which images were grouped together. EEG data were recorded continuously throughout the task.
After reviewing EEG data, the researchers found that the brains of people with epilepsy produce slow waves lasting less than a second while they are awake and participating in tasks.
The occurrence of these “awakening” slow waves increased in response to increased brain excitability, reducing the influence of epileptic spikes on brain activity.
In particular, it reduces the “firing” of nerve cells, which the researchers say can prevent epileptic activity.

Implications and future research

Lead author Professor Matthew Walker (UCL Queen Square Institute of Neurology) said: “Sleep is crucial for repairing, maintaining, and resetting brain activity. When we are awake, our brains gradually become more excitable, which recovers during sleep.
“Recent research has shown that a specific form of brain activity, namely slow waves during sleep, plays an important role in these restorative functions. We believe that these ‘sleep’ slow waves , we wanted to consider whether this could occur during wakefulness in response to the abnormal increase in brain activity associated with epilepsy.
“This study reveals for the first time ‘arousal’ slow waves, a potential protective mechanism used by the brain to counter epileptic activity. This mechanism takes advantage of brain defense activity that normally occurs during sleep, but can also occur during wakefulness in epileptic patients. ”
As part of the study, the team also wanted to test whether the occurrence of “awake” slow waves had a negative impact on cognitive function.
Researchers found that during memory tasks, “awake” slow waves reduced neuronal activity, thus affecting cognitive performance and increasing the time patients needed to complete the task.
The researchers reported that for every additional slow wave per second, reaction time increased by 0.56 seconds.
Professor Walker said: “This observation suggests that the cognitive impairments experienced by epilepsy patients, particularly memory impairments, may be due in part to short-term impairments caused by these slow waves. “
The research team hopes that future studies will increase such activity as a potential new treatment for epilepsy patients.
Lead author Dr Laurent Sheibany (UCL Queen Square Institute of Neurology) said:
“Our study suggests that naturally occurring activity is utilized by the brain to offset pathological activity. However, slow waves of ‘wake’ may have no effect on memory performance. This comes at a cost because we know we give.
“From a purely neurobiological perspective, this study also supports the idea that sleep activity does not occur uniformly throughout the brain, but may occur in specific regions of the brain.”
Reference: “Awakening slow waves in focal human epilepsy affect network activity and cognition” November 29, 2023 nature communications.
DOI: 10.1038/s41467-023-42971-3
This research was funded by the Medical Research Council, Wellcome, UCLH Biomedical Research Center and the Swiss National Science Foundation.

Source: scitechdaily.com