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NASA aims for Saturday launch of new moon rocket after fixes. Here’s what to expect – Global News

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NASA aimed for a Saturday launch of its new moon rocket, after fixing fuel leaks and working around a bad engine sensor that foiled the first try.

The inaugural flight of the 322-foot (98-meter) rocket – the most powerful ever built by NASA – was delayed late in the countdown Monday. The Kennedy Space Center clocks started ticking again as managers expressed confidence in their plan and forecasters gave favorable weather odds.

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NASA sets relaunch of Artemis moon rocket for Saturday after delay

Atop the rocket is a crew capsule with three test dummies that will fly around the moon and back over the course of six weeks – NASA’s first such attempt since the Apollo program 50 years ago. NASA wants to wring out the spacecraft before strapping in astronauts on the next planned flight in two years.

NASA Administrator Bill Nelson said he’s more confident going into this second launch attempt, given everything engineers learned from the first try.

So is astronaut Jessica Meir, who’s on NASA’s short list for one of the initial moon crews.

“We’re all excited for this to go, but the most important thing is that we go when we’re ready and we get it right, because the next missions will have humans on board. Maybe me, maybe my friends,” Meir told The Associated Press on Friday.


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NASA’s Artemis I moon mission launch scrubbed


NASA’s Artemis I moon mission launch scrubbed

The engineers in charge of the Space Launch System rocket insisted Thursday evening that all four of the rocket’s main engines were good and that a faulty temperature sensor caused one of them to appear as though it were too warm Monday. The engines need to match the minus-420 degrees Fahrenheit (minus-250 degrees Celsius) of the liquid hydrogen fuel at liftoff, otherwise they could be damaged and shut down in flight.

“We have convinced ourselves without a shadow of a doubt that we have good-quality liquid hydrogen going through the engines,” said John Honeycutt, the rocket’s program manager.

Once fueling begins Saturday morning, the launch team will perform another engine test _ this time earlier in the countdown. Even if that suspect sensor indicates the one engine is too warm, other sensors can be relied on to ensure everything is working correctly and to halt the countdown if there’s a problem, Honeycutt told reporters.

Read more:

NASA poised for Artemis moon rocket launch 50 years after Apollo: Here’s what to know

NASA could not perform that kind of engine test during dress rehearsals earlier this year because of leaking fuel. More fuel leaks cropped up Monday; technicians found some loose connections and tightened them.

The engine-temperature situation adds to the flight’s risk, as does another problem that cropped up Monday: cracks in the foam insulation of the rocket. If any foam pieces break off at liftoff, they could strike the strap-on boosters and damage them. Engineers consider the likelihood of that happening low and have accepted these slight additional risks.

“This is an extremely complicated machine and system. Millions of parts,” NASA’s chief, Nelson, told the AP. “There are, in fact, risks. But are those risks acceptable? I leave that to the experts. My role is to remind them you don’t take any chances that are not acceptable risk.”

Read more:

Canadian youth join NASA flight surveying climate change effects: ‘It was really cool’

The $4.1 billion test flight is NASA’s first step in sending astronauts around the moon in 2024 and landing them on the surface in 2025. Astronauts last walked on the moon in 1972.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

© 2022 The Canadian Press

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Tonga volcano blast was unusual, could even warm the Earth – Kelowna Capital News – Kelowna Capital News

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When an undersea volcano erupted in Tonga in January, its watery blast was huge and unusual — and scientists are still trying to understand its impacts.

The volcano, known as Hunga Tonga-Hunga Ha’apai, shot millions of tons of water vapor high up into the atmosphere, according to a study published Thursday in the journal Science.

The researchers estimate the eruption raised the amount of water in the stratosphere — the second layer of the atmosphere, above the range where humans live and breathe — by around 5%.

Now, scientists are trying to figure out how all that water could affect the atmosphere, and whether it might warm Earth’s surface over the next few years.

“This was a once-in-a-lifetime event,” said lead author Holger Voemel, a scientist at the National Center for Atmospheric Research in Colorado.

Big eruptions usually cool the planet. Most volcanoes send up large amounts of sulfur, which blocks the sun’s rays, explained Matthew Toohey, a climate researcher at the University of Saskatchewan who was not involved in the study.

The Tongan blast was much soggier: The eruption started under the ocean, so it shot up a plume with much more water than usual. And since water vapor acts as a heat-trapping greenhouse gas, the eruption will probably raise temperatures instead of lowering them, Toohey said.

It’s unclear just how much warming could be in store.

Karen Rosenlof, a climate scientist at the National Oceanic and Atmospheric Administration who was not involved with the study, said she expects the effects to be minimal and temporary.

“This amount of increase might warm the surface a small amount for a short amount of time,” Rosenlof said in an email.

The water vapor will stick around the upper atmosphere for a few years before making its way into the lower atmosphere, Toohey said. In the meantime, the extra water might also speed up ozone loss in the atmosphere, Rosenlof added.

But it’s hard for scientists to say for sure, because they’ve never seen an eruption like this one.

The stratosphere stretches from around 7.5 miles to 31 miles (12 km to 50 km) above Earth and is usually very dry, Voemel explained.

Voemel’s team estimated the volcano’s plume using a network of instruments suspended from weather balloons. Usually, these tools can’t even measure water levels in the stratosphere because the amounts are so low, Voemel said.

Another research group monitored the blast using an instrument on a NASA satellite. In their study, published earlier this summer, they estimated the eruption to be even bigger, adding around 150 million metric tons of water vapor to the stratosphere — three times as much as Voemel’s study found.

Voemel acknowledged that the satellite imaging might have observed parts of the plume that the balloon instruments couldn’t catch, making its estimate higher.

Either way, he said, the Tongan blast was unlike anything seen in recent history, and studying its aftermath may hold new insights into our atmosphere.

—Maddie Burakoff, The Associated Press

RELATED: Flights sent to assess Tonga damage after volcanic eruption

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NASA is slamming a spacecraft into an asteroid on Monday to test planetary defence – CBC.ca

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On Monday, in what seems like a scene out of a science fiction movie, NASA will slam a spacecraft into a distant asteroid to see whether it can nudge its orbit — all in an effort to test a way to protect Earth from any potential future threats.

The good news is that there’s no need to panic: The asteroid, which is part of a binary — or two-bodied — system, is not a threat to our planet, and there are no known ones that are headed our way for at least the next 100 years. However, space agencies like the U.S. National Aeronautics and Space Administration want to be prepared should there ever be a threat.

NASA’s Double Asteroid Redirection Test (DART) is testing a way in which a spacecraft may be able to nudge an asteroid on a collision course with Earth out of its orbit.

At 7:14 p.m. ET on Monday, the refrigerator-sized spacecraft will plunge itself into Dimorphos — a moonlet that orbits its larger companion, Didymos — at roughly 6.6 km/s.

The goal isn’t to knock Dimorphos out of orbit but rather to change its 12-hour orbit around Didymos by 10 minutes. This means that scientists will know within roughly 12 hours whether they were successful.

So why target a binary asteroid system rather than a single asteroid to see whether you can change its orbit around the sun?

This image of the light from asteroid Didymos and its orbiting moonlet, Dimorphos, is a composite of 243 images taken by the Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO) on July 27. (NASA JPL DART Navigation Team)

“A binary system was perfect for this test,” said Mallory DeCoster, a senior scientist at Johns Hopkins University’s Applied Physics Laboratory in Maryland and part of the DART Impact Modeling Working Group.

For one, the size of Dimorphos — about 164 metres across — is perfect to illustrate whether this would be an effective way of deflecting asteroids that pose a threat to Earth. Didymos is 780 metres across.

“But then the other piece is, if we were to impact a single asteroid, in order to characterize if we changed its orbit, we would have to wait until it completed its orbit around the sun, which could take many, many years.”

The other advantage is that the binary system is relatively close to us, astronomically speaking, at just 11 million kilometres away.

Shooting gallery

NASA’s Center for Near-Earth Object Studies says that more than 90 per cent of near-Earth objects (NEOs) bigger than one kilometre have already been discovered. But that doesn’t mean we’re out of the woods when it comes to Potentially Hazardous Asteroids (PHAs).

In 2013, the Chelyabinsk asteroid — which was roughly 20 metres in diameter— exploded over parts of Russia, injuring about 1,000 people and serving as a reminder of how even a small asteroid can be dangerous.

In February 2013, a meteorite contrail was seen over Chelyabinsk, Russia, a city close to the Ural Mountains located about 1,500 kilometres east of Moscow. The Chelyabinsk asteroid, which was roughly 20 metres in diameter, exploded over parts of Russia, injuring about 1,000 people. (Chelyabinsk.ru, Yekaterina Pustynnikova/The Associated Press)

Basically, Earth flies through a shooting gallery in space. There are small chunks of debris that burn up in our atmosphere as meteors; bigger ones, like Chelyabinsk; and then even bigger ones that can be catastrophic — all left over from the formation of our solar system.

That’s why space agencies like NASA and the European Space Agency have been trying to develop ways to deflect or nudge a PHA so that its orbit changes and poses no threat to Earth.

Mike Daly, a professor at York University’s Lassonde School of Engineering in Toronto and a co-investigator on DART, said one of the most popular concepts is deflecting asteroids before they become a real threat. But that means we need to have advance warning that one is headed our way.

“So the simplest method is the one that DART is doing, which is essentially to take a spacecraft at high speed and crash it into the asteroid and use that transfer of the energy from the spacecraft to the asteroid to move it along,” he said.

This infographic shows the potential effect of DART’s impact on the orbit of Dimorphos. (NASA/Johns Hopkins APL)

However, the science behind asteroid deflection in this manner is about more than just the combination of the spacecraft’s size and incredibly high speed, called a hypervelocity impact.

“In a hypervelocity impact, you induce this pressure wave into the target that causes a lot of new physics to happen,” Johns Hopkins University’s DeCoster said.

“So what will happen, or what we think will happen, is that the size of the spacecraft might actually not matter that much. It might actually be: How does the asteroid respond to this pressure wave that is induced due to the hypervelocity impact? And we think that it will likely spew out a lot of material in the form of ejecta. And this ejecta might actually have a major component for changing the orbit. So much ejecta might get spewed out that that piece might matter more than the incoming energy from the spacecraft in changing its orbit.”

The DART team hopes that an onboard camera, called DRACO, will show the close approach and then suddenly go black, which would be indicative of an impact.

This map shows the 38 telescopic facilities in space and around the globe that are expected to observe the Didymos asteroid system in support of DART’s global observation campaign after impact. Numerical figures in parentheses next to the telescope names indicate the telescope size. (NASA/Johns Hopkins APL/Nancy Chabot/Mike Halstad)

But there’s a straggler tagging along behind DART, by about three minutes: the Italian Space Agency’s Light Italian Cubesat for Imaging of Asteroids, or LICIACube. Its job is to photograph the impact, study the plume of ejecta and help determine the morphology of the asteroid, as they can be made of iron, rock or just rocky clumps held together by gravity.

As this is the first test of a form of planetary defence, scientists are eagerly anticipating not only the impact of the event itself but what they will learn from it and, most importantly, what this may mean for the future of protecting Earth in the future. Telescopes from around the world will be observing the event and collecting followup data.

“We’re really the first generation that can protect ourselves from these potentially catastrophic impacts,” York University’s Daly said. “And, you know, fortunately the really catastrophic ones don’t happen very often, but they could happen, and never before have we been able to change our fate. So I think it’s really up to us, given the potentially large consequences of not paying attention and our ability to do it.”

The event will be broadcast on NASA TV, which is available online and through its app.

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‘Planetary defence’: NASA targets asteroid in space collision – Al Jazeera English

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After NASA deliberately smashes a car-sized spacecraft into an asteroid next week, it will be up to the European Space Agency’s Hera mission to investigate the “crime scene” and uncover the secrets of these potentially devastating space rocks.

NASA’s Double Asteroid Redirection Test (DART) aims to collide with the asteroid moonlet Dimorphos on Monday night, hoping to slightly alter its trajectory – the first time such an operation has been attempted.

While Dimorphos is 11 million kilometres (6.8 million miles) away and poses no threat to Earth, the mission is a test run in case the world someday needs to deflect an asteroid from heading our way.

Astronomers around the world will watch DART’s impact and its effect will be closely followed to see if the mission passed the test.

The European Space Agency’s Hera mission, named after the ancient Greek queen of the gods, will follow in its footsteps.

The Hera spacecraft is planned to launch in October 2024, aiming to arrive at Dimorphos in 2026 to measure the exact impact DART had on the asteroid.

Scientists are not only excited to see DART’s crater, but also to explore an object very much out of this world.

[embedded content]

‘A new world’

Dimorphos, which orbits a larger asteroid Didymos as they hurtle together through space, provides not only a “perfect testing opportunity for a planetary defence experiment, but it is also a completely new environment”, Hera Mission Manager Ian Carnelli said.

Hera will be loaded with cameras, spectrometers, radars and even toaster-sized nano-satellites to measure the asteroid’s shape, mass, chemical composition and more.

NASA’s Bhavya Lal said it was critically important to understand the size and composition of such asteroids.

“If an asteroid is made up of, for example, loose gravel, approaches to disrupt it may be different than if it was metal or some other kind of rock,” she told the International Astronautical Congress in Paris this week.

So little is known about Dimorphos that scientists will discover “a new world” at the same time as the public on Monday, Hera mission Principal Investigator Patrick Michel said.

“Asteroids are not boring space rocks – they are super exciting because they have a great diversity” in size, shape and composition, Michel said.

Because they have low gravity compared with Earth, matter there could behave completely differently than expected. “Unless you touch the surface, you cannot know the mechanical response,” he said.

[embedded content]

‘Behaved almost like fluid’

For example, when a Japanese probe dropped a small explosive near the surface of the Ryugu asteroid in 2019, it was expected to make a crater of two to three metres. Instead, it blasted a 50-metre hole.

“There was no resistance,” Michel said. “The surface behaved almost like a fluid [rather than solid rock]. How weird is that?”

One way the Hera mission will test Dimorphos will be to land a nano-satellite on its surface, in part to see how much it bounces.

Binary systems such as Dimorphos and Didymos represent about 15 percent of known asteroids, but have not yet been explored.

With a diameter of just 160 metres – around the size of the Great Pyramid of Giza – Dimorphos will also be the smallest asteroid ever studied.

Learning about the impact of DART is not only important for planetary defence, Michel said, but also for understanding the history of our solar system, where most cosmic bodies were formed through collisions and are now riddled with craters.

That is where DART and Hera could shine a light not just on the future but on the past.

This computer-generated image shows the impact of the DART projectile on the binary asteroid system Didymos [European Space Agency via AFP]

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