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Registred the highest level of microplastics on the seabed – Prensa Latina

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1 de mayo de 2020, 12:23Washington, May 1 (Prensa Latina) The seafloor currently has the highest levels of microplastics since records exist, according to international research on the subject.

According to estimates, more than 10 million tons of plastic waste reach the oceans each year, and 99 percent goes to the deep.

A study by U.K., German and French agencies, published in the journal Science, showed how deep-sea currents become conveyor belts, carrying small pieces of plastic and fibers across the seafloor.

Such currents can concentrate microplastics within large accumulations of sediment, which the researchers called ‘microplastic hot spots’ (equivalent to so-called ‘garbage patches’).

Almost everyone has heard of the infamous ‘garbage patches’ of plastic floating in the ocean, but we were surprised by the high concentration of microplastics found deep in the sea floor’, said Ian Kane, of the University of Manchester and lead author of the research.

We discovered that the microplastics, he added, are not evenly distributed in the study area but are concentrated in certain spaces by powerful currents on the sea floor. Microplastics on the seafloor are mainly composed of textile and clothing fibres, which do not filter effectively in domestic wastewater treatment plants and enter rivers and oceans easily.

This study will help predict the location of other microplastic hotspots in deep waters and directly investigate their impact on marine life.

Our results highlight the need for policy interventions to limit the future flow of plastics into natural environments and minimize impacts on ocean ecosystems’, said Mike Clare of the UK’s National Oceanography Centre.

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SpaceX Crew Dragon launch: what to expect from the company’s first human mission to space – The Verge

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On the afternoon of May 30th, SpaceX is slated to launch its very first passengers to space, potentially heralding a new era of human spaceflight for the United States. It’ll be the first time in nearly a decade that people have launched to orbit from American soil, and it’ll be the first time that a private vehicle takes them there.

This historic flight is really a test. It’s the last big milestone for SpaceX as part of NASA’s Commercial Crew Program. The experimental initiative tasked private companies with creating new spacecraft for NASA that are capable of transporting astronauts to and from the International Space Station. SpaceX’s contribution to the program is a sleek, gumdrop-shaped capsule called the Crew Dragon. While it’s flown a few times before, the capsule has yet to carry people to space.

SpaceX spent the last six years getting to this point. Last year, the company did a full dress rehearsal, successfully launching the Crew Dragon to the station without a crew on board. The company also tested the capsule’s emergency escape system, confirming that the Crew Dragon can carry people to safety if something goes wrong during the launch. But there have been setbacks to overcome, too, including rocket failures and the explosion of a Crew Dragon capsule during a ground test last year. SpaceX has since recovered, referring to the failures as “gifts” that helped the company create a safer vehicle.

Now, it’s time for the Crew Dragon to have a crew. The vehicle’s first two passengers are veteran NASA astronauts Bob Behnken and Doug Hurley, who were assigned to this mission in 2018. After two years of training for this flight with both NASA and SpaceX, they’re ready to don SpaceX’s custom space suits and take their seats inside the capsule.

Here’s why this flight is so important, what to expect from the mission, and what it means for NASA and SpaceX moving forward.

The Importance

July 8th, 2011, marked the final flight of NASA’s Space Shuttle and the last time astronauts launched to orbit from the United States. Ever since, NASA has flown all of its astronauts and international partners to the space station on Russia’s Soyuz capsule. The arrangement costs NASA about $80 million per seat — and it has been the agency’s only option for getting people to the station.

To end its reliance on another country, NASA worked with private industry to bring human spaceflight back to the United States. With the Commercial Crew Program, NASA awarded two companies — SpaceX and Boeing — contracts to develop their own vehicles that could ferry NASA’s astronauts to the space station and back. NASA paid SpaceX $3.14 billion to develop and fly the Crew Dragon, while Boeing received $4.8 billion to develop and fly the CST-100 Starliner.

An intense rivalry formed between the two companies over the years. Both experienced numerous technical delays and setbacks along the way, but ultimately, SpaceX pulled ahead. When it flies, SpaceX will become the first private company ever to fly humans to orbit.

The Launch

SpaceX’s Falcon 9 rocket will take off from the company’s launch site at NASA’s Kennedy Space Center in Cape Canaveral, Florida. Known as Launch Complex 39A, it’s seen launches of the Space Shuttle as well as Saturn V rockets that sent humans to the Moon. SpaceX started leasing the complex from NASA in 2014 and transformed the launchpad to support flights of the company’s Falcon 9 and Falcon Heavy rockets.

Suited up in SpaceX’s custom pressure suits, astronauts Behnken and Hurley will start making their way to the launchpad at around 12PM ET. To really make this an Elon Musk affair, the two astronauts will ride to the site in a white Tesla Model X, adorned with various NASA logos for absolute synergy. Once at the pad, the duo will take an elevator up near the top of the Falcon 9 rocket and walk across a suspended hallway known as the “crew access arm” to the entrance of the Crew Dragon.

Behnken and Hurley will climb inside the capsule and shut the hatch, which will mean it’s time to start fueling the vehicle. This part of the process has been fairly controversial for some in the aerospace community. Back when the Space Shuttle was flying, fueling occurred before astronauts boarded since loading combustible materials into a spacecraft is considered risky. However, SpaceX opts to do fueling about half an hour before launch, after the crew is already on board. The company uses incredibly cold propellants to fly its Falcon 9, which boost the vehicle’s performance. The sooner SpaceX pumps in that propellant before launch, the less time there is for the liquids to warm up and boil away.

After years of debate over this procedure — called “load and go” — NASA finally signed off when SpaceX demonstrated it could be safely done on numerous flights.

Once all the propellant is loaded in the rocket, things will happen quickly. SpaceX will give the go-ahead to launch, with liftoff scheduled for 3:22PM ET. The company must launch at that exact time or be forced to delay to the backup launch date, which is currently set for Saturday, May 30th.

The Docking

If all goes as planned, it’s a quick trip to Earth orbit for the two astronauts. The Falcon 9 rocket will release the Crew Dragon into low Earth orbit about 12 minutes after takeoff. The rocket will then return to Earth where it is scheduled to land on a drone ship in the Atlantic Ocean.

For the next 19 hours, the astronauts will orbit the planet. During that time, the Crew Dragon will raise its orbit slightly by periodically igniting its engines in order to catch up with the International Space Station. Inside the capsule, Behnken and Hurley will try to get some sleep — and perhaps use the capsule’s onboard toilet if nature calls.

The Crew Dragon is designed to require minimal input from its passengers, but since this is a test, Hurley and Behnken will do some manual flying before they reach the space station. “It’s obviously something that we want to make sure we understand completely for future crews in case they ever have to fly the vehicle manually,” Hurley said during a press conference. The plan is for Hurley to take control right after Crew Dragon reaches orbit as well as when they approach the space station.

But really, this is a time for the Crew Dragon’s autonomous docking system to shine. It’s a feature that the previous cargo version of SpaceX’s Dragon lacked when carrying supplies to the ISS. During those cargo missions, an astronaut on board the space station used a robotic arm to grab hold of an approaching Dragon capsule and draw it close to the ISS. Now, with the upgraded Crew Dragon, the capsule shouldn’t need any help from humans. Once Hurley is done flying manually near the station, the Crew Dragon’s automatic system will kick in. Using a series of sensors and cameras, the capsule will fly itself toward the ISS and hook itself onto an open docking port.

If the launch proceeds as planned, docking should take place at 10:29AM ET on Sunday, May 31st.

The Return

Once the Crew Dragon’s hatch is opened, Behnken and Hurley will join NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner on the ISS. Hurley said Cassidy recently sent them an email about their impending reunion in space. “He said something about he’s looking forward to seeing our ugly mugs onboard space station,” Hurley recalled.

Originally, NASA planned to keep the astronauts at the space station for only a few weeks. But plans changed as delays in the Commercial Crew Program prolonged the development of SpaceX and Boeing’s vehicles. The first crewed flights were supposed to take place in 2017, and with the expectation that these vehicles would be regularly flying by now, NASA purchased a limited number of seats on Russia’s Soyuz rocket. Those seats started to run out, and now Cassidy is tasked with all American-led operations on the space station.

About six months ago, NASA decided to extend Behnken and Hurley’s stay on board in order to maintain a bigger crew on the ISS. Now it seems likely they’ll be up in space for a few months, though NASA hasn’t decided yet when the astronauts will return. The Crew Dragon can only stay in space for about four months because of its solar panels. The thin atmosphere in space degrades the panels over time, limiting the vehicle’s lifetime in orbit.

NASA says it will make the decision about the crew’s return date while they’re in space. As an added bit of insurance, NASA recently purchased one more seat on a Soyuz flight for this fall in case of further delays with the Commercial Crew vehicles.

When the time comes, Behnken and Hurley will climb back into their Crew Dragon, close the hatch, and detach from the space station. They’ll distance themselves from the ISS and then eventually take the plunge through Earth’s atmosphere. A suite of four parachutes will lower them down, allowing them to splash safely in the Atlantic Ocean off the Florida coast.

The Unthinkable

SpaceX has spent years doing tests and inspections to ensure that this launch performs safely. But this launch is a test, and the specter of failure weighs heavily on many minds. If something goes awry, a built-in emergency escape system will provide an extra layer of protection for the astronauts.

Embedded inside the outer walls of the Crew Dragon are tiny thrusters called SuperDraco engines. These thrusters are designed to ignite during flight in case something goes catastrophically wrong. The SuperDracos can carry the Crew Dragon up and away from a malfunctioning rocket, and once far enough away, the capsule’s parachutes can deploy, lowering the vehicle down into the Atlantic Ocean.

It’s a maneuver that’s only needed in the case of an emergency, but SpaceX claims this option is available during every point in the flight until the Crew Dragon is deployed into orbit. And that actually means NASA and SpaceX are fairly limited about when this mission can launch. An abort could bring the Crew Dragon down in an extremely wide area of ocean in the Atlantic, and NASA wants to make sure that the weather is good in every possible location the capsule could touch down.

“We’re actually looking at waves — we’re looking at wave velocity and wave height — because we need to make sure that if the crew has to come down in a launch escape scenario, that they would come down in a sea state that would keep them safe and the rescue forces would be able to come and get them,” Benji Reed, director of crew mission management at SpaceX, said during a press conference. SpaceX will be considering the weather in more than 50 locations all the way up the East Coast to Canada and even across the Atlantic to Northern Ireland. That means weather delays are more likely than not.

SpaceX already postponed its first launch attempt on May 27th, due to bad weather around the launch site that may have triggered lightning. The weather doesn’t look very good for May 30th either; the 45th Space Wing in Florida predicted a 40 percent chance that conditions will be favorable for launch. It’s the same for the backup launch day on May 31st.

The Future

Once Behnken and Hurley are back on Earth with their families, it’ll be time to start making these kinds of trips routine — which is what the Commercial Crew Program is all about. SpaceX and NASA will pore over the data gathered during this test flight and use that information to certify the Crew Dragon for regular flights to and from the ISS.

SpaceX’s next, fully operational mission of the Crew Dragon will then just be a few months away. That flight will carry a crew of four: NASA astronauts Victor Glover, Mike Hopkins, and Shannon Walker as well as Japanese astronaut Soichi Noguchi. Their flight is expected to occur in early fall, cementing a new age where commercial companies are routinely taxiing people to NASA’s space station.

Update May 28th, 3:00PM ET: This story was updated to include new launch times for the mission.

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Tesla's Musk earns $770M in stock options, company confirms – Powell River Peak

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DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

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Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

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SpaceX’s historic NASA astronaut launch debut on track for second attempt – Teslarati

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Rather than making history on May 27th, SpaceX’s highest-profile launch ever – Crew Dragon’s NASA astronaut launch debut – was scrubbed just minutes before liftoff by stormy Florida weather. Unfortunately, conditions appear to be even less favorable on Saturday and Sunday backup windows.

Weather trended well, until it didn’t

The day began with launch fans growing increasingly concerned about a system of low-pressure off of Florida’s northeast coast that strengthened into tropical storm Bertha – the second named storm before the official start of the Atlantic basin hurricane season on June 1st. As the day progressed, Bertha became less of a worry for SpaceX recovery and emergency abort drop zones as it moved further north up the coast eventually making landfall in South Carolina. Then the thunderstorms began firing up.

Hans Koenigsmann, vice president for build and flight reliability at SpaceX, looks at a monitor showing a live feed of a SpaceX Falcon 9 rocket carrying the company’s Crew Dragon spacecraft on the launch pad during the countdown for a launch attempt of NASA’s SpaceX Demo-2 mission. (Credit: NASA/Joel Kowsky)

Going into launch day launch weather officer, Mike McAleenan of the U.S. Space Force’s 45th Weather Squadron predicted a 60% chance of favorable launch weather conditions. That decreased slightly to 50% during the morning’s launch weather briefing. The 50/50 shot of Florida weather cooperating to get the launch off during the one-second long launch window opportunity remained the main concern for the rest of the day.

An ominous thunderstorm rolls over LC-39A ahead of SpaceX’s ultimately scrubbed first attempt to launch the Crew Dragon Demo-2 test flight on Wednesday, May 27th. (Credit: Richard Angle for Teslarati)

During the final thirty minutes of the countdown, many of the weather constraints that were holding up a green-light for launch from cleared up, but one last weather rule remained no-go. McAleenan stated over the internal weather communication loop during NASA’s live broadcast that if the launch window could’ve extended another 10 minutes, the weather would probably cooperate. This wasn’t the case, though. The launch attempt was ultimately aborted just 14 minutes shy of liftoff due to the “field mill” rule not clearing in time. The lightning field mill rule refers to a sophisticated electrical field system that spans the entire area of Kennedy Space Center and the surrounding area of Cape Canaveral responsible for continuously detecting the electrical charge of the atmosphere.

Protecting rockets from producing lightning

Rockets are not permitted to launch through an electrically charged atmosphere because of the possibility of what is called “triggered” lightning – lightning that is actually produced by a rocket bursting through an electrically charged atmosphere. Sending a rocket through an already unstable atmosphere can cause a disturbance, a lightning bolt, to be triggered. This phenomenon has the capability of being potentially dangerous for the rocket and, more importantly in this case, the occupants on board.

A very helpful infographic published by the 45th Weather Squadron regarding the natural and triggered lightning launch rules. (Credit: 45th Weather Squadron)

Demo-2, Round 2

Following a scrubbed first attempt, the 45th Weather Squadron released the L-3 (3 days until launch) forecast for the second attempt to send NASA astronauts Doug Hurley and Bob Behnken to the International Space Station. The prediction looked much like the one going into Wednesday’s attempt. On Thursday morning, May 28th, a new L-2 (2 days until launch) forecast was released showing very little change from the evening before.

SpaceX’s next attempt at a Demo-2 launch will occur on Saturday, May 30th, at 3:22:41pm EDT with another backup attempt scheduled for Sunday, May 31st at 3:00:07pm EDT. The outlook for the weather, however, looks much the same as it did for Wednesday. The 45th Weather Squadron is currently predicting only a 40% chance of favorable launching conditions on both days, and that’s just for the weather directly over LC-39A at the time of launch.

A L-3 weather forcast provided by the U.S. Space Force’s 45th Weather Squadron outlines a 40% chance of acceptable weather conditions at time of launch for SpaceX’s back-up attempt to lauch the first ever crewed mission, Demo-2, on Saturday, May 30th. (Credt: U.S. Space Force – 45th Weather Squadron)

The 45th Weather Squadron does not predict other conditions that can determine a scrub of launch including upper-level atmospheric winds capable of completely sheering apart a rocket at altitude, or weather conditions for booster recovery and the recovery zones needed to rescue the Dragon capsule in the event of an emergency abort scenario. SpaceX has its own team of professionals that work in tandem with the 45th Weather Squadron to monitor the conditions of the recovery and abort zones. SpaceX takes things into consideration like wave height and patterns to determine whether or not conditions are appropriate enough for crews to perform any and all recovery operations that may be needed.

For Saturday’s attempt, the SpaceX Demo-2 will once again face the challenges of precipitation and dangerous lightning producing anvil and cumulus clouds. Expect launch day to look much like it did during the first attempt on Wednesday. SpaceX will need to thread one seriously precise needle to pull off the most historic rocket launch in company history.

Check out Teslarati’s newsletters for prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket launch and recovery processes.

SpaceX’s historic NASA astronaut launch debut on track for second attempt




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