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Asteroids Appear Rough Due to Space Dust Hopping on Them, Suggests Research

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By ANI | Updated: 12 July 2022

According to a new study from physicists at the University of Colorado Boulder, like corn kernels pop in a frying pan, tiny grains of dust may hop around on the surface of asteroids.

That popcorn-like effect may even help to tidy up smaller asteroids, causing them to lose dust and look rough and craggy from space.

The researchers published their results in the journal Nature Astronomy. Their findings may help scientists better understand how asteroids change shape over time—and how these bodies migrate through space, sometimes bringing them dangerously close to Earth, said Hsiang-Wen (Sean) Hsu, lead author of the study.

“The more fine-grained material, or regolith, these asteroids lose, the faster they migrate,” said Hsu, a research associate at the Laboratory for Atmospheric and Space Physics (LASP) at CU Boulder.

The research began with a few curious photos.

In 2020, a NASA spacecraft named OSIRIS-REx travelled more than 1 billion miles to rendezvous with the asteroid (191055) Bennu, which is about as tall as the Empire State Building. But when the spacecraft arrived, scientists didn’t find what they were expecting: The asteroid’s surface looked like rough sandpaper, not smooth and dusty like researchers had predicted. There were even large boulders scattered over its exterior.

Now, Hsu and his colleagues have drawn on computer simulations, or models, and laboratory experiments to explore that puzzle. He said that forces akin to static electricity may be kicking the smallest grains of dust, some no bigger than a single bacterium, off the asteroid and into space–leaving only larger rocks behind.

Bennu isn’t alone, said study co-author Mihaly Horanyi.

“We’re realizing that these same physics are occurring on other airless bodies like the moon and even the rings of Saturn,” said Horanyi, a researcher at LASP and professor of physics at CU Boulder.

Bennu and Ryugu

Asteroids might look like they’re frozen in time, but these bodies evolve throughout their lifetimes.

Hsu explained that asteroids like Bennu are constantly spinning, which exposes their surfaces to sunlight, then shadow and sunlight again. That never-ending cycle of heating and cooling puts a strain on the largest rocks at the surface, until they inevitably crack.

“It’s happening every day, all the time,” Hsu said. “You wind up eroding a big piece of rock into smaller pieces.”

Which is why, before scientists arrived at Bennu, many were expecting to find it covered in smooth sand—a bit like how the moon looks today. Not long before, a Japanese space mission landed on a second small asteroid called Ryugu. The team found a similarly rough and craggy terrain. Hsu and his colleagues were suspicious.

Since the 1990s, researchers at LASP have used vacuum chambers in the lab to investigate the strange properties of dust in space, including a feat they call “electrostatic lofting.” Study co-lead author Xu Wang explained that as the sun’s rays bathe small grains of dust, they begin to pick up negative charges. Those charges will build until, suddenly, the particles burst apart, like two magnets repelling each other.

In some cases, those grains of dust can pop away at speeds of more than 20 miles per hour (or more than 8 meters per second).

“No one had ever considered this process on the surface of an asteroid before,” said Wang, a research associate at LASP.

Small asteroid, big asteroid

To do that, the researchers, including former CU Boulder undergraduate students Anthony Carroll and Noah Hood, ran a series of calculations examining the physics of regolith on two hypothetical asteroids. They tracked how dust might form, then hop around over hundreds of thousands of years. One of those faux asteroids was about a half-mile across (similar in size to Ryugu) and the second several miles wide (closer in diameter to big asteroids like Eros).

The size made a difference. According to the team’s estimates, when grains of dust jumped on the bigger asteroid, they couldn’t gain enough speed to break free of its gravity. The same wasn’t true on the smaller, Ryugu-like asteroid.

“The gravity on the smaller asteroid is so weak that it can’t hold back the escape,” Hsu said. “The fine-grained regolith will be lost.”

That lost dust, in turn, will expose the surface of the asteroids to even more erosion, leading to a boulder-rich scenery like scientists found on Ryugu and Bennu. Within several million years, in fact, the smaller asteroid was almost completely swept clean of fine dust. The Eros-like asteroid, however, stayed dusty.

Hsu noted that this scrubbing effect could help to give the orbits of small asteroids a nudge. He explained that asteroids migrate because the sun’s radiation pushes on them slowly over time. Based on previous research by other scientists, he suspects that asteroids covered in boulders may move faster than those with a dustier appearance.

He and his colleagues may soon get more proof to back up their calculations. In less than 3 months, a NASA mission called the Double Asteroid Redirection Test (DART) will visit a pair of smaller asteroids—and Hsu will be watching to see how dusty they are.

“We will have new surface images to test our theory,” he said. “It’s nice for us, but also a little nerve-wracking.”

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NASA’s Artemis 1 Launch Faces Another Obstacle, Next Launch Window in October

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By Agence France-Presse | Updated: 24 September 2022

NASA’s historic uncrewed mission to the Moon is facing fresh difficulties. After technical problems derailed two launch attempts several weeks ago, a new liftoff of the Artemis 1 mission scheduled for Tuesday is now threatened by a storm gathering in the Caribbean.

The storm, which has not yet been assigned a name, is currently located south of the Dominican Republic.

But it is expected to grow into a hurricane in the coming days and could move north to Florida, home to the Kennedy Space Center, from which the rocket is set to launch.

“Our plan A is to stay to course and to get the launch off on September 27,” Mike Bolger, NASA’s exploration ground systems manager, told reporters on Friday. “But we realised we also need to be really paying attention and thinking about a plan B.”

That would entail wheeling the giant Space Launch System rocket back to the Vehicle Assembly Building, known as VAB.

“If we were to go down to Plan B we need a couple days to pivot from our current tanking test or launch configuration to execute rollback and get back into the protection of the VAB,” Bolger said, adding that a decision should be made by early afternoon on Saturday.

On the launch pad the orange and white SLS rocket can withstand wind gusts of up to 137 kilometres per hour. But if it has to be sheltered, the current launch window, which runs until October 4, will be missed.

The next launch window will run from October 17 to 31, with one possibility of take-off per day, except from October 24-26 and 28.

A successful Artemis 1 mission will come as a huge relief to the US space agency, after years of delays and cost overruns. But another setback would be a blow to NASA, after two previous launch attempts were scrapped when the rocket experienced technical glitches including a fuel leak.

The launch dates depend on NASA receiving a special waiver to avoid having to retest batteries on an emergency flight system that is used to destroy the rocket if it strays from its designated range to a populated area.

On Tuesday the launch window will open at 11:37 local time and will last 70 minutes.

If the rocket takes off that day, the mission will last 39 days before it lands in the Pacific Ocean on November 5.

The Artemis 1 space mission hopes to test the SLS as well as the unmanned Orion capsule that sits atop, in preparation for future Moon-bound journeys with humans aboard.

Mannequins equipped with sensors are standing in for astronauts on the mission and will record acceleration, vibration and radiation levels.

The next mission, Artemis 2, will take astronauts into orbit around the Moon without landing on its surface.

The crew of Artemis 3 is to land on the Moon in 2025 at the earliest.

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Astronomers Spot Hot Gas Bubble Spinning Clockwise Around Milky Way Black Hole

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By Agence France-Presse | Updated: 22 September 2022

Astronomers said Thursday they have spotted a hot bubble of gas spinning clockwise around the black hole at the centre of our galaxy at “mind blowing” speeds.

The detection of the bubble, which only survived for a few hours, is hoped to provide insight into how these invisible, insatiable, galactic monsters work.

The supermassive black hole Sagittarius A* lurks in the middle of the Milky Way some 27,000 light years from Earth, and its immense pull gives our home galaxy its characteristic swirl.

The first-ever image of Sagittarius A* was revealed in May by the Event Horizon Telescope Collaboration, which links radio dishes around the world aiming to detect light as it disappears into the maw of black holes.

One of those dishes, the ALMA radio telescope in Chile’s Andes mountains, picked up something “really puzzling” in the Sagittarius A* data, said Maciek Wielgus, an astrophysicist at Germany’s Max Planck Institute for Radio Astronomy.

Just minutes before ALMA’s radio data collection began, the Chandra Space Telescope observed a “huge spike” in X-rays, Wielgus told AFP.

This burst of energy, thought to be similar to solar flares on the Sun, sent a hot bubble of gas swirling around the black hole, according to a new study published in the journal Astronomy and Astrophysics.

The gas bubble, also known as a hot spot, had an orbit similar to Mercury’s trip around the Sun, the study’s lead author Wielgus said.

But while it takes Mercury 88 days to make that trip, the bubble did it in just 70 minutes. That means it travelled at around 30 percent of the speed of light.

“So it’s an absolutely, ridiculously fast-spinning bubble,” Wielgus said, calling it “mind blowing”.

A MAD theory

The scientists were able to track the bubble through their data for around one and half hours – it was unlikely to have survived more than a couple of orbits before being destroyed.

Wielgus said the observation supported a theory known as MAD. “MAD like crazy, but also MAD like magnetically arrested discs,” he said.

The phenomenon is thought to happen when there is such a strong magnetic field at the mouth of a black hole that it stops material from being sucked inside.

But the matter keeps piling up, building up to a “flux eruption”, Wielgus said, which snaps the magnetic fields and causes a burst of energy.

By learning how these magnetic fields work, scientists hope to build a model of the forces that control black holes, which remain shrouded in mystery.

Magnetic fields could also help indicate how fast black holes spin – which could be particularly interesting for Sagittarius A*.

While Sagittarius A* is four million times the mass of our Sun, it only shines with the power of about 100 suns, “which is extremely unimpressive for a supermassive black hole, Wielgus said.

“It’s the weakest supermassive black hole that we’ve seen in the universe – we’ve only seen it because it is very close to us.”

But it is probably a good thing that our galaxy has a “starving black hole” at its centre, Wielgus said.

“Living next to a quasar,” which can shine with the power of billions of suns, “would be a terrible thing,” he added.

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Cyborg Cockroaches Powered by Solar Cells Could Help First Responders in Disaster Areas: Details

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By Reuters | Updated: 22 September 2022

If an earthquake strikes in the not too distant future and survivors are trapped under tonnes of rubble, the first responders to locate them could be swarms of cyborg cockroaches.

That’s a potential application of a recent breakthrough by Japanese researchers who demonstrated the ability to mount “backpacks” of solar cells and electronics on the bugs and control their motion by remote control.

Kenjiro Fukuda and his team at the Thin-Film Device Laboratory at Japanese research giant Riken developed a flexible solar cell film that’s 4 microns thick, about 1/25 the width of a human hair, and can fit on the insect’s abdomen.

The film allows the roach to move freely while the solar cell generates enough power to process and send directional signals into sensory organs on the bug’s hindquarters.

The work builds upon previous insect-control experiments at Nanyang Technological University in Singapore and could one day result in cyborg insects that can enter hazardous areas much more efficiently than robots.

“The batteries inside small robots run out quickly, so the time for exploration becomes shorter,” Fukuda said. “A key benefit (of a cyborg insect) is that when it comes to an insect’s movements, the insect is causing itself to move, so the electricity required is nowhere near as much.”

Fukuda and his team chose Madagascar hissing cockroaches for the experiments because they are big enough to carry the equipment and have no wings that would get in the way. Even when the backpack and film are glued to their backs, the bugs can traverse small obstacles or right themselves when flipped over.

The research still has a long way to go. In a recent demonstration, Riken researcher Yujiro Kakei used a specialized computer and wireless Bluetooth signal to tell the cyborg roach to turn left, causing it to scramble in that general direction. But when given the “right” signal, the bug turned in circles.

The next challenge is miniaturising the components so that the insects can move more easily and to allow for mounting of sensors and even cameras. Kakei said he constructed the cyborg backpack with JPY 5,000 (roughly Rs. 2,700) worth of parts purchased at Tokyo’s famed Akihabara electronics district.

The backpack and film can be removed, allowing the roaches to go back to life in the lab’s terrarium. The insects mature in four months and have been known to live up to five years in captivity.

Beyond disaster rescue bugs, Fukuda sees broad applications for the solar cell film, composed of microscopic layers of plastic, silver, and gold. The film could be built into clothing or skin patches for use in monitoring vital signs.

On a sunny day, a parasol covered with the material could generate enough electricity to charge a mobile phone, he said.

© Thomson Reuters 2022

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SpaceX to Seek Iran Sanctions Exemption to Bring Starlink Satellite Internet Connectivity, Elon Musk Says

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By Agence France-Presse | Updated: 21 September 2022

SpaceX will apply for an exemption from US sanctions against Iran in a bid to offer its satellite internet service to the country, owner Elon Musk said on Monday.

“Starlink will apply for an exemption from sanctions against Iran,” Musk said in response to a tweet from a science reporter.

Musk had initially announced that the Starlink satellite internet service had been made available on every continent – “including Antarctica” – with the company planning to launch up to 42,000 satellites to boost connectivity.

Iranian-born science journalist Erfan Kasraie had said on Twitter that bringing the service to Iran could be a “real game changer for the future” of the country, which elicited Musk’s response.

Launched at the end of 2020, Starlink offers high-speed broadband service to customers in areas poorly served by fixed and mobile terrestrial networks through a constellation of satellites in low earth orbit.

The service received notoriety after supplying antennas and modems to the Ukrainian military to improve its communications capabilities in its war with Russia.

Starlink is monetised through the purchase of antennas, modems, and subscriptions with rates that vary by country.

Nearly 3,000 Starlink satellites have been deployed since 2019 and SpaceX is conducting about one launch a week, using its own Falcon 9 rockets to speed up its deployment.

Iran has been under a tightened US sanctions regime since former president Donald Trump terminated a 2015 agreement over its nuclear activities.

While current President Joe Biden supports a renegotiation of the deal, Iranian insistence on long-term guarantees from Washington has stalled discussions.

New rounds of sanctions were imposed on Iran this month after a Tehran-based company helped ship drones to Russia, and in response to a massive cyberattack targeting Albania in July allegedly carried out by Iran’s intelligence ministry.

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NASA, Roscosmos Astronauts Set to Blast Off for ISS on Soyuz Rocket Amid Tensions Over Ukraine Conflict

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By Agence France Press | Updated: 21 September 2022

A US astronaut and two Russian cosmonauts are set to blast off to the International Space Station Wednesday on a Russian-operated flight despite soaring tensions between Moscow and Washington over Russia’s invasion of Ukraine.

NASA’s Frank Rubio and Russia’s Sergey Prokopyev and Dmitry Petelin are scheduled to take off from the Russia-leased Baikonur cosmodrome in Kazakhstan at 1354 GMT (7:24pm IST), according to Russian space agency Roscosmos.

Rubio will become the first US astronaut to travel to the ISS on a Russian Soyuz rocket since President Vladimir Putin sent troops into pro-Western Ukraine on February 24.

In response, Western capitals including Washington have hit Moscow with unprecedented sanctions and bilateral ties have sunk to new lows.
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However, space has managed to remain an outlier of cooperation between the two countries.

Following Rubio’s flight, Russia’s only active female cosmonaut Anna Kikina is expected to travel to the orbital station in early October aboard a SpaceX Crew Dragon.

She will become only the fifth professional woman cosmonaut from Russia or the Soviet Union to fly to space, and the first Russian to fly aboard a spacecraft of SpaceX, the company of US billionaire Elon Musk.

With both flights set to go ahead, Russian cosmonauts and Western astronauts have sought to steer clear of the conflict that is raging back on Earth, especially when in orbit together.

A collaboration among the United States, Canada, Japan, the European Space Agency, and Russia, the ISS is split into two sections: the US Orbital Segment, and the Russian Orbital Segment.

Russia leaving ISS

At present, the ISS depends on a Russian propulsion system to maintain its orbit, about 250 miles (400 kilometres) above sea level, with the US segment responsible for electricity and life support systems.

However, tensions in the space field have grown after Washington announced sanctions on Moscow’s aerospace industry – triggering warnings from Russia’s former space chief Dmitry Rogozin, an ardent supporter of the Ukraine war.

Rogozin’s recently appointed successor Yuri Borisov later confirmed Russia’s long-mooted move to leave the ISS after 2024 in favour of creating its own orbital station.

US space agency NASA called the decision an “unfortunate development” that would hinder the scientific work performed on the ISS.

Space analysts say that the construction of a new orbital station could take more than a decade and Russia’s space industry – a point of national pride – would not be able to flourish under heavy sanctions.

The ISS was launched in 1998 at a time of hope for US-Russia cooperation following their Space Race competition during the Cold War.

During that era, the Soviet space programme flourished. It boasted a number of accomplishments that included sending the first man into space in 1961 and launching the first satellite four years earlier.

But experts say Roscosmos is now a shadow of its former self and has in recent years suffered a series of setbacks, including corruption scandals and the loss of a number of satellites and other spacecraft.

Russia years-long monopoly on manned flights to the ISS is also gone, to SpaceX, along with millions of dollars in revenue.

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First public global database of fossil fuels launches

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By: Associated Press, September 20, 2022

A first-of-its-kind database for tracking the world’s fossil fuel production, reserves and emissions launches on Monday to coincide with climate talks taking place at the United Nations General Assembly in New York. The Global Registry of Fossil Fuels includes data from over 50,000 oil, gas and coal fields in 89 countries. That covers 75% of global reserves, production and emissions, and is available for public use, a first for a collection of this size.

Until now there has been private data available for purchase, and analysis of the world’s fossil fuel usage and reserves. The International Energy Agency also maintains public data on oil, gas and coal, but it focuses on the demand for those fossil fuels, whereas this new database looks at what is yet to be burned. The registry was developed by Carbon Tracker, a nonprofit think tank that researches the energy transition’s effect on financial markets, and the Global Energy Monitor, an organization that tracks a variety of energy projects around the globe.

Corporations, investors and scientists already have some level of access to private data on fossil fuels. Mark Campanale, founder of Carbon Tracker, said he hopes the registry will empower groups to hold governments accountable, for example, when they issue licenses for fossil fuel extraction.“Civil society groups have got to get more of a focus on what governments are planning to do in terms of license issuance, both for coal and oil and gas, and actually begin to challenge this permitting process,” Campanale told The Associated Press.

The release of the database and an accompanying analysis of the collected data coincide with two critical sets of climate talks at the international level — the U.N. General Assembly in New York beginning on September 13, and COP27 in Sharm El Sheikh, Egypt, in November. Data like what’s being released in the registry could arm environmental and climate groups to pressure national leaders to agree to stronger policies that result in less carbon emissions.

And we’re in dire need of carbon reductions, Campanale said. In their analysis of the data, the developers found that the United States and Russia have enough fossil fuel still underground untapped to exhaust the world’s remaining carbon budget. That’s the remaining carbon the world can afford to emit before a certain amount of warming occurs, in this case 1.5 degrees Celsius. It also shows these reserves would generate 3.5 trillion tons of greenhouse gas emissions, which is more than all of the emissions produced since the Industrial Revolution.

“We already have enough extractable fossil fuels to cook the planet. We can’t afford to use them all — or almost any of them at this point. We’ve run out of time to build new things in old ways,” said Rob Jackson, a Stanford University climate scientist who was not involved with the database.“I like the emphasis on transparency in fossil fuel production and reserves, down to specific projects. That’s a unique aspect to the work.”Jackson compared the global carbon budget to a bathtub.“You can run water only so long before the tub overflows,” he said.

When the tub is close to overflowing, he said, governments can turn down the faucet (mitigating greenhouse gas emissions) or open the tub’s drain more (removing carbon from the atmosphere).The database shows that we have much more carbon than we need as a global community, Campanale said, and more than enough to overflow the bathtub and flood the bathroom in Jackson’s analogy. So investors and shareholders should be holding decision makers at the world’s largest oil, gas and coal companies accountable when they approve new investments in fossil fuel extraction, he said.

Campanale said the hope is the investment community, “who ultimately own these corporations,” will use the data to begin to challenge the investment plans of companies still planning to expand oil, gas and coal projects. “Companies like Shell and Exxon, Chevron and their shareholders can use the analysis to to really begin to try and push the companies to move in a completely different direction.”

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