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NASA diligently awaits the 'Seven Minutes of Terror' Mars descent – haveeruonline

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NASA animation shows the rover landing of perseverance.
Gif: NASA / JBL-Caltech / Kismodo

In just 57 days, NASA’s diligent rover will attempt to land on Mars. Mission regulators say it will be a “seven-minute terror” as this new depiction proves dramatic.

Digital animation produced by NASA’s Jet Propulsion Laboratory depicts the key events of the rover’s entry, descent and landing (EDL). The video is over three minutes long Length, which is not less than the landing stage, should be seven Minutes. The diligence was launched on July 30th, And will perform EDL in February. 18, 2021 at 3:30 pm EST.

The $ 2.7 billion rover will land in the Xero gorge, the site of the former lake and river delta. With its many tools, diligence will look for signs of microbial life, study Mars weather and geography, and collect samples for future work on recovery. Rover ingenuity, A small helicopter is poised to become the first man-made aircraft to fly in an alien world.

Of course, perseverance must land if any of this is to happen. In fact, Mars is infamous for ending before it even gets a chance to start — ESA. Failure The latest example of Schiaparelli work in 2017.

The first phase of the EDL will see the evacuation of the ship phase delivering solar panels, radios and fuel tanks used during the Red Planet voyage. Descent status, as Diligence Approaching the atmosphere, shoot small thrusts at its rear to ensure the vehicle is properly aimed and the heat shield is facing forward. Descendant status will see the rover later Go through the thin Martian atmosphere at a speed of 12,000 miles (19,312) kph), According to To NASA. If this condition is to go as planned, the interior of the craft should not be warmer than room temperature.

A supersonic parachute will be deployed if the descent level drops to at least 1,000 mph (1,609 kph). NASA is about to launch a new system Limit trigger, To determine the most optimal moment to deploy the parachute, which should occur 240 seconds after atmospheric entry. The heat shield is then dropped as desired Will not be anymore Required For the first time Mars is exposing the rover to the atmosphere.

Another new technology, called Landscape-relative navigation, Will use video cameras and maps to select a safe place to land.

At maximum, the parachute will slow the vehicle down to 200 mph (322 kph), Running descent required. At 6,900 feet (2,100 m) above the surface of the diligence, the rocket-powered descent level enters and slows down the craft at a highly manageable 2 mph (3.2 km.). A ski crane would then slowly lower to 2,260Pound (1,025-Kilograms) Rover on the surface, which is 21 feet long (6.4-Meters long) Cables. The ski crane will cut the cables as soon as it senses a landing and then zip clearly from the target site.

Only Then Is real The fun begins as the rover is free to explore the surface of Mars. The diligent work is expected to last two years, but as the forerunner has shown, it is cWill last a long time. For example, NASA’s Curiosity rover landed on Mars in 2012, and it is still strong. We look forward to the work of perseverance, but first things first: it must escape the seven-minute terror.

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How to literally drive the coronavirus away – Deccan Herald

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Over the past year, as health authorities have tried to curb the Covid-19 pandemic, researchers have trained their scientific attention on a variety of potentially risky environments: places where large groups of people gather and the novel coronavirus has ample opportunity to spread. They have swabbed surfaces on cruise ships, tracked case numbers in gyms, sampled ventilation units in hospitals, mapped seating arrangements in restaurants and modeled boarding procedures in airplanes.

They have paid less attention to another everyday environment: the car. A typical car, of course, does not carry nearly enough people to host a traditional superspreader event. But cars come with risks of their own; they are small, tightly sealed spaces that make social distancing impossible and trap the tiny, airborne particles, or aerosols, that can transmit the coronavirus.

“Even if you’re wearing a face covering, you still get tiny aerosols that are released every time you breathe,” said Varghese Mathai, a physicist at the University of Massachusetts, Amherst. “And if it’s a confined cabin, then you keep releasing these tiny particles, and they naturally would build up over time.”

Read: Decoding how airflow inside car may affect Covid-19 transmission risk

In a new study, Mathai and three colleagues at Brown University — Asimanshu Das, Jeffrey Bailey and Kenneth Breuer — used computer simulations to map how virus-laden airborne particles might flow through the inside of a car. Their results, published in early January in Science Advances, suggest that opening certain windows can create air currents that could help keep both riders and drivers safe from infectious diseases like Covid-19.

To conduct the study, the research team employed what are known as computational fluid dynamic simulations. Engineers commonly use these kinds of computer simulations, which model how gases or liquids move, to create race cars with lower drag, for instance, or airplanes with better lift.

The team simulated a car loosely based on a Toyota Prius driving at 50 mph with two occupants: a driver in the front left seat and a single passenger in the back right,  a seating arrangement that is common in taxis and ride shares and that maximizes social distancing. In their initial analysis, the researchers found that the way the air flows around the outside of the moving car creates a pressure gradient inside the car, with the air pressure in the front slightly lower than the air pressure in the back. As a result, air circulating inside the cabin tends to flow from the back of the car to the front.

Next, they modeled the interior air flow — and the movement of simulated aerosols — when different combinations of windows were open or closed. (The air conditioning was on in all scenarios.) Unsurprisingly, they found that the ventilation rate was lowest when all four windows were closed. In this scenario, roughly 8% to 10% of aerosols exhaled by one of the car’s occupants could reach the other person, the simulation suggested. When all the windows were completely open, on the other hand, ventilation rates soared, and the influx of fresh air flushed many of the airborne particles out of the car; just 0.2% to 2% of the simulated aerosols traveled between driver and passenger.

The results jibe with public health guidelines that recommend opening windows to reduce the spread of the novel coronavirus in enclosed spaces. “It’s essentially bringing the outdoors inside, and we know that the risk outdoors is very low,” said Joseph Allen, a ventilation expert at the Harvard T.H. Chan School of Public Health. In an op-ed last year, he highlighted the danger that cars could pose for coronavirus transmission, and the potential benefits of opening the windows. “When you have that much turnover of air, the residence time, or how much time the aerosols stay inside the cabin, is very short,” Allen said

Because it is not always practical to have all the windows wide open, especially in the depths of winter, Mathai and his colleagues also modeled several other options. They found that while the most intuitive-seeming solution — having the driver and the passenger each roll down their own windows — was better than keeping all the windows closed, an even better strategy was to open the windows that are opposite each occupant. That configuration allows fresh air to flow in through the back left window and out through the front right window and helps create a barrier between the driver and the passenger.

“It’s like an air curtain,” Mathai said. “It flushes out all the air that’s released by the passenger, and it also creates a strong wind region in between the driver and the passenger.”

Richard Corsi, an air quality expert at Portland State University, praised the new study. “It’s pretty sophisticated, what they did,” he said, although he cautioned that changing the number of passengers in the car or the driving speed could affect the results.

Read | Consumers prioritising car ownership post-coronavirus lockdown, 74% want own vehicle: Survey

Corsi, a co-author of the op-ed with Allen last year, has since developed his own model of the inhalation of coronavirus aerosols in various situations. His results, which have not yet been published, suggest that a 20-minute car ride with someone who is emitting infectious coronavirus particles can be much riskier than sharing a classroom or a restaurant with that person for more than an hour.

“The focus has been on superspreader events” because they involve a lot of people, he said. “But I think what sometimes people miss is that superspreader events are started by somebody who’s infected who comes to that event, and we don’t speak often enough about where that person got infected.”

In a follow-up study, which has not yet been published, Mathai found that opening the windows halfway seemed to provide about the same benefit as opening them fully, while cracking them just one-quarter of the way open was less effective.

Mathai said that the general findings would most likely hold for many four-door, five-seat cars, not just the Prius. “For minivans and pickups, I would still say that opening all windows or opening at least two windows can be beneficial,” he said. “Beyond that, I would be extrapolating too much.”

Ride-sharing companies should be encouraging this research, Mathai said. He sent a copy of his study to Uber and Lyft, he said, but has not received a response.

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The Olduvai Gorge gives up two-million-year-old secrets – Varsity

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Few archaeological sites can claim to be famous, but the Olduvai Gorge in northern Tanzania is chief among them. With the word ‘olduvai’ coming from a misspelling of the Maasai word, ‘oldupai,’ a name for a plant that grows in the area, the fossil-rich region is famous for offering up some of the first evidence of fossil remains and stone tools used by early hominins, ancestors of today’s humans.

In the 1930s, Louis and Mary Leakey were working in Olduvai when they uncovered stone tools from early humans. Since then, it has become a popular archaeological site. The gorge lent an even older name — the Oldoway Gorge — to the paleolithic culture discovered there before the Abbevillian culture and, subsequently, their tools. Oldowan tools are often either large hammering stones or smaller, sharper flake stones used for cutting. They were used by precursors to modern Homo sapiens, such as Homo habilis.

Now, an international research team comprised of scientists from around the world, including from U of T, have conducted a thorough search of the Olduvai Gorge and concluded that hominins were living and building tools in the site as early as two million years ago. Moreover, their continual occupation of the gorge, extending over a 235,000-year period, shows how early hominins could adapt to changing environments — a skill that might have aided in their expansion out of Eastern Africa.

A wide source of information

The researchers combed through a wide array of sources to reach their findings. They took samples from previously excavated fossils and tools and compared them against samples of pollen, plants, and charcoal from wildfires, which were all deposited into the soil millions of years ago. The result was a pattern of human activity in the same place across time.

The prehistoric Olduvai landscape contained a variety of environments, such as streams, floodplains, woody forest, dry steppe, and even patches of land covered by ash from volcanic activity. Early hominins were able to exploit all of these environments, partly by bringing materials they needed for tools with them. Some of the rocks used to make tools originated 12 kilometres from where they were found. Others were made using what was at hand.

However, it is not clear which hominin species made these tools, largely because no new fossils were found. One possible candidate is Homo habilis because their fossils have been excavated nearby.

Rethinking the past

Oldowan tools have been excavated in nearby Ethiopia dating back to 2.6 million years ago, so this study does not represent the earliest discovery of stone tools. But it does extend the timeline of the Olduvai Gorge specifically. Previously, the oldest use of tools in the region was dated to 1.85 million years ago, so these findings push that start point by about 150,000 years. 

Moreover, these new findings demonstrate that early hominins had a robust ability to adapt to new environments. Julio Mercader Florin, lead author and professor at the University of Calgary, wrote in The Conversation that “This is a clear sign that 2 million years ago humans were not constrained technologically and already had the capacity to expand geographic range.”

The researchers discovered that the tools used remained the same regardless of what environment they were found in. It might have been human adaptability, then, that enabled our ancestors to thrive in the Olduvai Gorge and beyond.

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Test fire of NASA's SLS moon rocket ends prematurely – CTV News

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NASA’s Space Launch System rocket ignited its four main engines Saturday on a test stand in Mississippi, but the engines shut down earlier than the agency planned.

The hot fire test was the last of eight tests that make up what NASA calls a “green run,” a series of ground tests aimed at ensuring the vehicle doesn’t have any major structural or engineering issues before it is put on a launch pad. The rocket is the most powerful launch vehicle the space agency has ever constructed.

The SLS was supposed to light its engines for about eight minutes, the length of time the engines will have to fire to propel the rocket on its orbital missions.

It’s not yet clear why the engines powered down after little more than a minute at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. The test was still useful for gathering data and “teams are assessing the data on early engine shutdown,” the space agency tweeted.

During a Saturday night news conference, John Honeycutt, the SLS program manager, said NASA officials will go over the data gathered in the test to identify the issue.

“What we learned was — is that we didn’t have the pressurization valve modeled appropriately,” Honeycutt said.

Officials had hoped to run the test for at least 250 seconds, he said.

During the hot fire test, engineers “power up all the core stage systems, load more than 700,000 gallons of cryogenic, or supercold, propellant into the tanks and fire all four engines at the same time,” according to NASA.

It is unclear if another test will be needed before the rocket is shipped to Florida, the launch site where the rocket is expected to make its first journey into outer space.

Rick Gilbrech, director of the Stennis Space Center, said his site would need at least four to five days to prepare the fuel for another test if the rocket is ready. He and his team aren’t discouraged by Saturday’s test and are proud of what they’ve accomplished this year, especially during the Covid-19 pandemic, he said.

NASA administrator Jim Bridenstine said the test was “not a failure.”

“This is not a failure. This is a test, and we tested today in a way that is meaningful where we’re going to learn … we’re going to make adjustments, and we’re going to fly to the moon,” he said.

“This was a successful day. We didn’t get everything we wanted and yes we’re going to learn, we’re going to have to make adjustments,” he said. “But again, this is a test. And this is why we test.”

 

Yet another delay

 

SLS has been haunted by critiques of long delays and cost overruns, and with the premature end of the critical hot fire test, its launch may be delayed once again.

“We got lots of data that we’re going to go through and be able to sort through and get to a point where we can make determinations as to whether or not, you know, launching in 2021 is a possibility or not,” Bridenstine said.

The rocket is a key part of NASA’s Artemis lunar exploration program, which aims to send the first woman and next man to the moon by 2024. NASA officials also hope the SLS will be used to reach Mars and other “deep space destinations.”

SLS has been under development for a decade. Under the Obama administration, NASA was already planning to use SLS to take astronauts back to the moon by 2028, and that remained the plan until Vice President Mike Pence directed the space agency to drastically accelerate its timeline in 2019.

Boeing was contracted in 2012 to build SLS’s main components, and the rocket was originally expected to start flying in December 2017. But Boeing has been blasted in several government oversight reports for “poor performance,” costly schedule slips and ballooning expenses. That made SLS a touchy political talking point, and many in the space industry remain suspicious that a 2024 moon landing is possible.

At one point, Bridenstine reportedly considered skipping the green run test to expedite SLS’s development. But more recently he has asserted that the tests are essential to ensuring the rocket is safe enough to carry humans into space and to work out any potential engineering problems before attempting an orbital launching.

Bridenstine is expected to step down when President-elect Joe Biden is inaugurated next week. It’s not clear if NASA will stick with the 2024 timeline under the new administration, though the official Democratic platform calls for “continuity” in NASA’s space programs between presidential administrations.

The SLS rocket stands taller than the Statue of Liberty and has about 15% more thrust at liftoff than the Saturn V rockets that powered the Apollo missions about 50 years ago.

NASA’s Artemis I mission is expected to launch by the end of 2021 with two test flights around the moon without astronauts.

A crewed test mission, Artemis II, is set to launch in 2023 in preparation to have the Artemis III mission return astronauts to the surface of the moon in 2024 for the first time since the 1970s.

Artemis is named after the Greek goddess of the moon and is the twin sister of Apollo, which was name NASA used for the missions and spacecraft that first took Americans to the moon in 1969.

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