Tag Archives: titans

Tech Titans Bowing Down to President Trump in Silicon Valley

Posted on by
Reply

On January 28, 2017, I hurried to San Francisco International Airport (SFO). That evening, protests were gaining momentum across the United States against President Donald Trump’s travel ban on visitors from seven Muslim-majority countries. The night was unusually cold, and I had not brought a proper jacket. Luckily, the train to the airport was warm and filled with nervous and chatty protesters. The airport itself was chaotic. Angry demonstrators blocked roads, causing taxis and Ubers to be stranded with meters still running. A hijab-wearing protester prayed next to a protest sign in the baggage claim area, while others shouted at travelers collecting their luggage. At that time, Trump was the most controversial figure in America, and his election had shocked the world.

Later that night, rumors of a $150 billion face in the crowd started to circulate. Sergey Brin, the founder and co-founder of Google, was present. At that time, he was the president of Alphabet, Google’s parent company, which also owns YouTube. The impact was electrifying. One of the wealthiest and most influential men in the world was publicly expressing his displeasure with Trump by participating in a protest against him. Brin, originally from Moscow and immigrating to the United States at the age of 6, stated he was at SFO that night “because I’m a refugee,” delivering a personal rebuke to Mr. Trump, whom he described as a complete xenophobe.


Following Brin’s lead, Google and other tech giants condemned Trump’s travel ban. Nearly 100 technology companies, including Facebook, Apple, Microsoft, and Uber, supported a lawsuit challenging the measure.

However, today’s protests against President Trump’s reelection have had minimal impact. Silicon Valley is shifting its stance to show more deference to Mr. Trump. This week, the tech industry finished its nominations for the upcoming president.

Meta CEO Mark Zuckerberg announced the cessation of the company’s fact-checking operations in the United States. In 2022, Meta had claimed to have built the largest global fact-checking network and spent $100 million on it.

A few days later, Mr. Zuckerberg revealed a reduction in efforts to enhance workforce diversity, equity, and inclusion (DEI) – a move met with controversy. These policies had been disdained by Trump and faced criticism from his prominent supporter, Elon Musk. Zuckerberg, seemingly driven by ambition rather than personal beliefs, took actions such as promoting Dana White to Meta’s board of directors after dining with Trump and supporting his inaugural committee.

Mr. Zuckerberg’s actions seemed to be influenced by Trump’s threats, as the president-elect had warned of dire consequences if Zuckerberg interfered in the election. Mehta, like others, stood to benefit from a friendly Trump administration, particularly concerning Meta’s antitrust lawsuit.

Several tech CEOs, including Tim Cook, Sundar Pichai, and Satya Nadella, also demonstrated support for President Trump, each contributing in different ways. Uber CEO Dara Khosrowshahi donated $2 million to Trump, and even Google made a substantial donation despite being targeted by Trump’s campaign.

The president-elect, noticing his newfound popularity, remarked on the change in attitude towards him. Meanwhile, Musk’s threats loomed over tech leaders like Jeff Bezos, Sam Altman, and Jensen Huang, demonstrating the power dynamics at play in the tech industry.

Source: www.theguardian.com

Cassini uncovers the properties of Titan’s hydrocarbon sea

Posted on by
Reply

Saturn’s moon Titan was explored by NASA’s Cassini spacecraft between 2004 and 2017. Although Cassini revealed much about this Earth-like world, its radar observations provided limited information about Titan’s liquid hydrocarbon oceans: Kraken, Ligeia, and Punga Mare. New paper In the journal Nature CommunicationsCornell University researcher Valerio Poggiali and his colleagues reported the results of their analysis of data from the Cassini radar experiment on Titan’s polar oceans.

Artistic depiction of Kraken Mare, a giant ocean of liquid methane on Titan. Image courtesy of NASA John Glenn Research Center.

“The Cassini spacecraft explored Saturn’s largest moon, Titan, between 2004 and 2017, revealing an Earth-like world with a strange yet very familiar diversity of surface morphologies formed by a methane-based hydrological system operating in a dense nitrogen atmosphere,” said Dr Poggiali and his co-authors.

“Winds in the lower atmosphere move the sediments, forming the vast sand dunes that encircle Titan’s equator.”

“At mid-latitudes, flat, relatively featureless plains form the transition between the eolianite-dominated equator and the lacustrine-dominated poles.”

“In the polar regions, large oceans and small lakes of liquid hydrocarbons dominate the landscape.”

“The channels created by precipitation drain into the ocean, forming estuaries and sometimes deltas and other familiar coastal deposits.”

“Cassini has revealed much about Titan, but this discovery raises even more questions.”

For the study, scientists used data from four bistatic radar observations collected by Cassini during four flybys in 2014 (May 17, June 18, and October 24) and 2016 (November 14).

For each, surface reflections were observed when the probe was closest to Titan (approach) and when it was moving away (exit).

The authors analyzed data from outflow observations of Titan’s three large polar oceans: Kraken Mare, Ligeia Mare, and Punga Mare.

“In a bistatic radar experiment, a spacecraft directs a radio beam towards a target, in this case Titan, where the beam is reflected towards a receiving antenna on Earth,” the researchers explained.

“This surface reflection is polarized, which means it provides information gathered from two independent perspectives, as opposed to the perspective provided by monostatic radar data, where the reflected signal is sent back to the spacecraft.”

“The main difference is that the bistatic information is a more complete data set and is sensitive to both the composition of the reflective surface and its roughness.”

The team found that the composition of the ocean’s surface layers of hydrocarbons varies depending on latitude and location (for example, near rivers or estuaries).

Specifically, the southernmost parts of Kraken Mare exhibit the highest dielectric constant, a measure of a material’s ability to reflect radio signals.

For example, water on Earth is highly reflective and has a dielectric constant of about 80, while Titan’s ethane and methane oceans have a dielectric constant of about 1.7.

The researchers also determined that ocean conditions in all three areas were fairly calm during the flyby, with surface waves measuring less than 3.3 mm.

Slightly higher levels of roughness, up to 5.2 mm, were found in coastal areas, near estuaries and straits, which could be an indication of tidal currents.

“There are also indications that the rivers that feed the oceans are pure methane until they flow into the open ocean liquid, which is rich in ethane,” Dr Poggiali said.

“It’s the same as when freshwater rivers flow into the saltwater of the ocean on Earth and mix together.”

“This fits well with weather models of Titan, which predict that the ‘rain’ falling from Titan’s skies is almost pure methane, with traces of ethane and other hydrocarbons,” said Professor Philip Nicholson of Cornell University.

“Further studies of the data Cassini has collected during its 13-year exploration of Titan are already underway.”

“There’s still a mountain of data waiting to be fully analyzed in a way that will lead to further discoveries. This is just the first step.”

_____

V. Poggiali others2024. Surface characteristics of Titan’s ocean as revealed by the Cassini bistatic radar experiment. Nat Community 15, 5454; doi: 10.1038/s41467-024-49837-2

This article is a version of a press release provided by Cornell University.

Source: www.sci.news

Study shows wave activity causing erosion along the coastlines of Titan’s largest lakes and oceans

Posted on by
Reply

Titan, Saturn’s largest moon, is the only known planet other than Earth that still retains liquid water. Liquid hydrocarbons fed by rain from Titan’s thick atmosphere form rivers, lakes, and oceans, most of which are found in the polar regions. In a new study, a team of MIT geologists surveyed Titan’s coastline and found that the moon’s large lakes and oceans were likely formed by waves.

Artist’s rendering of the surface of Saturn’s largest moon, Titan. Image by Benjamin de Bivort, debivort.org / CC BY-SA 3.0.

The existence of waves on Titan has been a somewhat controversial topic ever since NASA’s Cassini spacecraft discovered liquid puddles on Titan’s surface.

“Some people who have looked for evidence of waves haven’t seen any waves at all and have said, ‘The ocean is as smooth as a mirror,'” said Dr. Rose Palermo, a geologist with the U.S. Geological Survey. “Others have said they saw some roughness in the water but didn’t know if it was caused by waves.”

“Knowing whether there is wave activity in Titan’s oceans can provide scientists with information about the moon’s climate, including the strength of the winds that generate such waves.”

“Wave information could also help scientists predict how the shape of Titan’s ocean will change over time.”

“Rather than looking for direct signs of wave-like features in Titan images, we wanted to take a different approach and see if just looking at the shape of the coastline could tell us what it is that is eroding the coast.”

Titan’s oceans are thought to have formed when rising waters flooded a landscape crisscrossed by river valleys.

The researchers zeroed in on three scenarios for what happened next: no coastal erosion, wave-driven erosion, and uniform erosion caused by either dissolution, where liquids passively dissolve coastal material, or a mechanism where the coast gradually peels away under its own weight.

They simulated how different coastline shapes would change under each of the three scenarios.

To simulate wave erosion, the researchers took into account a variable called “fetch,” which describes the physical distance from one point on the shoreline to the other side of a lake or ocean.

“Wave erosion depends on the height and angle of the waves,” Dr Palermo said.

“We used the fetch to estimate wave height because the bigger the fetch, the further away the wind will blow and the bigger the waves will be.”

Cassini observed Titan’s surface with microwaves and found several grooves that are deep canyons filled with liquid hydrocarbons, including Vid Fulmina, a branching network of thin lines in the upper left quadrant of the image. Image credit: NASA / JPL-Caltech / ASI.

To test how coastline shape would differ between the three scenarios, the scientists started with a simulated ocean area with a flooded river valley all around it.

For wave erosion, we calculated the fetch distance from every point along the coastline to every other point and converted that distance to wave height.

They then ran simulations to see how waves would erode the original shoreline over time.

They compared this to how the same coastline would change due to erosion caused by uniform erosion.

The authors repeated this comparative modelling for hundreds of different initial shoreline configurations.

They found that the shape of the termini varies greatly depending on the underlying mechanism.

Most notably, uniform erosion produced a bulging shoreline that was evenly distributed all around, even in flooded river valleys, whereas wave erosion smoothed out portions of the shoreline exposed primarily to long downstream distances, leaving the flooded valleys narrow and rough.

“Although the initial coastline was the same, we found that uniform erosion and wave erosion resulted in very different final shapes,” Dr Perron said.

“Although it looks like a flying spaghetti monster because of the flooded river valley, the endpoints created by the two types of erosion are very different.”

This image is a composite of images taken during two flybys of Titan in 2006. A large circular feature near the center of Titan’s disk may be the remnant of a very old impact basin. The mountain range southeast of the circular feature and the long, dark linear feature northwest of the old impact site may be the result of deformation of Titan’s crust caused by energy released when the impact occurred. Image credit: NASA/JPL/University of Arizona.

Dr. Perron and his colleagues verified their results by comparing their simulation results with actual lakes on Earth.

They found the same shape differences between Earth’s lakes known to have been eroded by waves and those affected by homogeneous erosion, such as dissolved limestone.

Their modelling revealed distinct and distinctive shapes depending on the mechanism by which the shoreline evolved.

So they wondered: Where does Titan’s coastline fit into these distinctive shapes?

In particular, they focused on four of Titan’s largest and best-mapped oceans: Kraken Mare, which is comparable in size to the Caspian Sea; Ligeia Mare, which is larger than Lake Superior; Punga Mare, which is longer than Lake Victoria; and Lake Ontario, which is about 20% the size of the land-based lake of the same name.

The researchers used Cassini’s radar images to map the coastlines of each of Titan’s oceans, and then applied their model to the coastlines of each ocean to see which erosion mechanisms best explain their shape.

They found that all four oceans fit closely to the wave-induced erosion model, meaning that waves created the closest coastlines to Titan’s four oceans.

“We found that when the shoreline is eroding, its shape is more consistent with wave-driven erosion than uniform erosion or no erosion,” Dr Perron said.

Scientists are trying to figure out how strong Titan’s winds would need to be to churn up waves strong enough to repeatedly scrape away the shoreline.

They also hope to learn from the shape of Titan’s coastline which direction the winds primarily blow from.

“Titan shows us that this case is completely pristine,” Dr. Palermo said.

“It may help us learn more fundamental things about how coasts erode without human influence, which in turn may help us better manage coastlines around the world in the future.”

of Investigation result Published in today’s journal Scientific advances.

_____

Rose V. Palermo others2024. Evidence of wave erosion on Titan’s coast. Scientific advances 10(25); Source: 10.1126/sciadv.adn4192

Source: www.sci.news

Titan’s underground ocean revealed by Cassini observations

Posted on by
Reply

Titan, Saturn’s largest moon, harbors an ocean of low-density water or ammonia inside, according to an analysis of archival data from NASA’s Cassini mission.

A representation of Cassini’s orbit used to calculate Titan’s gravity. The colored part of the orbit shows the distance from Cassini to Titan, with the minimum distance shown in red. A cross-section of Titan shows the moon’s different layers and blue oceans. In the background you can see Saturn with its rings and ring shadows. Image credit: Britt Griswold, NASA Goddard Space Flight Center.

“Liquid water is one of the prerequisites for life,” said Dr. Sander Goossens of NASA’s Goddard Space Flight Center and colleagues.

“Water is rarely liquid on the surfaces of planets, but many moons of the solar system, such as Titan, have underground oceans.”

“These probably formed a long time ago, which begs the question why they haven’t already frozen in a cold environment far from the sun.”

“Our study supports the explanation that ammonia extended the life of Titan’s liquid oceans. Additionally, it also provides insight into Titan’s deeper layers.”

NASA’s Cassini mission explored Saturn and its icy moons for more than a decade.

Among its many instruments, Cassini carried a radio science subsystem that enabled radiation tracking of Earth-based spacecraft by the Deep Space Network.

These data were used to determine the gravitational field and internal structure of some of Saturn’s moons and Saturn itself. Cassini data was also used to determine Titan’s tidal response.

“The Cassini space probe flew around Saturn from 2005 to 2017,” the researchers said.

“Probes have been sent close to the moon many times to accurately measure Titan’s gravity.”

“Cassini needed to skim past Titan at exactly the right time to properly map the changes in gravity.”

“This is because Titan’s deformation is due to Saturn’s tidal forces, and the tidal forces depend on the distance between Titan and Saturn.”

“Measurements taken when Titan was close to Saturn and when it was far away maximized the difference in Titan’s deformation, and therefore its impact on gravity.”

Scientists calculated Cassini’s speed from precise radar measurements and calculated changes in gravity and the resulting deformation of Titan.

They carefully examined the tidal effects on Titan at each location on the spacecraft’s orbit and concluded that the deformation was smaller than previously calculated.

According to numerical simulations of the moon’s deformation for different internal structures, the most likely scenario is that the ocean has a density similar to water and contains small amounts of ammonia.

“The subsurface ocean may help transport organic matter from the moon’s rocky core to the surface,” the authors said.

“It was thought that Titan’s thick layer of ice between its ocean and its core made this difficult.”

“Our analysis suggests that the ice layer may be thinner than previously thought, and that material exchange between the rock and the ocean is more likely.”

“The organic molecules this produces are considered important ingredients for the emergence of life.”

of study It was published in the magazine natural astronomy.

_____

S. Goossens other. A low-density ocean inside Titan estimated from Cassini data. Nat Astron, published online March 21, 2024. doi: 10.1038/s41550-024-02253-4

Source: www.sci.news

Three-Carbon Compounds Found in Titan’s Atmosphere

Posted on by
Reply

Tricarbon molecule (C3) is probably produced in Titan’s upper atmosphere by the reaction of abundant acetylene with atomic carbon.

This view of Titan is one of the last images NASA’s Cassini spacecraft transmitted to Earth before entering the giant planet’s atmosphere. Image credit: NASA / JPL-Caltech / Space Science Institute.

Of the solar system’s more than 150 known moons, Saturn’s largest moon Titan is the only one with a substantial atmosphere.

And of all the places in the solar system, Titan is the only place other than Earth that is known to have liquid in the form of rivers, lakes, and oceans on its surface.

Titan is larger than Mercury and is the second largest moon in the solar system. Jupiter’s moon Ganymede is only slightly larger (about 2%).

Titan’s atmosphere is composed primarily of nitrogen, like Earth’s, but its surface pressure is 50% higher than Earth’s.

Titan has clouds of liquid hydrocarbons such as methane and ethane, rain, rivers, lakes, and oceans.

“Home to a thick and chemically diverse atmosphere, Titan stands out among the icy moons of the giant planets as one of the most thoroughly studied objects in the solar system,” said Lisboa Observatory and University of Astronomy. said Dr. Rafael Silva. of Lisbon.

“Titan’s atmosphere acts like a planet-sized chemical reactor, producing many complex carbon-based molecules.”

“Of all the atmospheres we know of in the solar system, it is most similar to the atmosphere thought to exist on early Earth.”

“Methane, which is a gas on Earth, provides information about geological and potentially biological processes.”

“This molecule cannot survive for long in the atmospheres of Earth or Titan because it is quickly and irreversibly destroyed by solar radiation.”

“Therefore, methane must be replenished on Titan by geological processes such as underground gas emissions.”

In the study, Dr. Silva and his colleagues UVES High Resolution Visible and Ultraviolet Spectrometer ESO’s Very Large Telescope.

They were able to identify 97 absorption lines for methane and one absorption line for the three-carbon molecule.

“Even in high-resolution spectra, the methane absorption lines are not strong enough for the amount of gas that can exist in a laboratory on Earth,” Dr. Silva said.

“But Titan has an entire atmosphere, and the path that light travels through the atmosphere can span hundreds of kilometers.”

“This allows various bands and lines that have weak signals in labs on Earth to be very obvious on Titan.”

“In our solar system, three-carbon molecules, which appear as bluish luminescence, were previously known only in the material surrounding the cores of comets.”

“The absorption lines in Titan that we have associated with tricarbons, although highly specific for this type of molecule, are small in number and low in intensity, so new observations will be needed in the future to confirm this detection.” will be done.”

“The more we learn about the different molecules involved in the chemical complexity of Titan’s atmosphere, the better we understand the types of chemical evolution that may have enabled or are associated with the origin of life on Earth.” You will be able to do it.”

“Some of the organic matter that contributed to the origin of life on Earth is thought to have been produced in the atmosphere by processes relatively similar to those observed on Titan.”

a paper The survey results were published in a magazine planetary space science.

_____

Rafael Lianzo Silva other. 2024. Study of Titan’s very high-resolution visible spectrum: Line characterization in visible CH.Four Search for band and C3. planetary space science 240: 105836; doi: 10.1016/j.pss.2023.105836

Source: www.sci.news