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NASA Moon rocket test met 90% of objectives –



NASA’s Artemis I Moon rocket sits at Launch Pad Complex 39B at Kennedy Space Center, in Cape Canaveral, Florida.

NASA’s fourth attempt to complete a critical test of its Moon rocket achieved around 90 percent of its goals, but there’s still no firm date for the behemoth’s first flight, officials said Tuesday.

Known as the “wet dress rehearsal” because it involves loading , it is the final item to cross off the checklist before the Artemis-1 mission slated for this summer: an uncrewed lunar flight that will eventually be followed by Moon boots on the ground, likely no sooner than 2026.

Teams at the Kennedy Space Center began their latest effort to complete the exercise on Saturday.

Their objectives were to load propellant into the rocket’s tanks, conduct a launch countdown and simulate contingency scenarios, then drain the tanks.

Three previous bids, starting in March, were plagued by glitches and failed to fuel up the rocket with hundreds of thousands of gallons of supercooled and .

On Monday, engineers finally succeeded in fully loading up the tanks. But they also encountered a new hydrogen leak issue they were unable to resolve.

“I would say we’re in the 90th percentile in terms of where we need to be overall,” Artemis mission manager Mike Sarafin told reporters Tuesday.

He added NASA was still deciding whether it needed another rehearsal, or could proceed straight to launch. The agency previously said an August window for Artemis-1 was possible.

NASA officials have repeatedly emphasized that delays involving the testing of new systems was common during the Apollo and Space Shuttle era, and the issues affecting SLS are not of major concern.

With the Orion crew capsule fixed on top, the Space Launch System (SLS) Block 1 stands 322 feet (98 meters) high—taller than the Statue of Liberty, but a little smaller than the 363 feet Saturn V rockets that powered the Apollo missions to the Moon.

It will produce 8.8 million pounds of maximum thrust (39.1 Meganewtons), 15 percent more than the Saturn V, meaning it’s expected to be the world’s most powerful rocket at the time it begins operating.

Artemis-1 is set to journey around the far side of the Moon sometime this summer on a .

Artemis-2 will be the first crewed test, flying around the Moon but not landing, while Artemis-3 will see the first woman and first person of color touch down on the lunar south pole.

NASA wants to build a permanent presence on the Moon, and use it as a proving ground for technologies necessary for a Mars mission, sometime in the 2030s.

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NASA Artemis I moon rocket rolls back to Kennedy Space Center launch pad

© 2022 AFP

NASA Moon rocket test met 90% of objectives (2022, June 21)
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Researchers pinpoint location of extremely energetic particles in a 'Space Manatee' – UM Today



July 4, 2022 — 

An international team of astrophysicists has identified the location where powerful and highly energetic x-rays are being shot out into space from inside a region in space shaped like a giant aquatic mammal called a “Manatee.” They found the spectrum of the object at this location shows there is a “non-classical acceleration process” where particles are being injected and re-accelerated in immensely powerful jets of energy emitted by a black hole. But don’t worry about it irradiating us, since it’s more than 100,000,000,000,000,000 kilometres away from us.

Samar Safi-Harb

The astronomical object known as SS 433 has long been known to house a black hole that is causing blasts of energy to spew out across the Milky Way through jets of highly energetic particles. Considered the first known microquasar, it’s at the centre of what’s left of an exploded star in the constellation Aquila, high up in the summer night sky.

“This fascinating system looks like a beautiful Manatee in space and represents the only known supernova remnant in our Galaxy (out of some 400 such objects) housing a black hole,” says UM astrophysicist Dr. Samar Safi-Harb, Tier 1 Canada Research Chair in Extreme Astrophysics and lead author of the paper that includes scientists from Canada, USA, Europe, and South Korea.

Brydyn Mac Intyre

Brydyn Mac Intyre

UM team member and grad student Brydyn Mac Intyre helped create a striking colour image of this remarkable astronomical object. The blasts of energy terminate at two “earlobes” glowing at radio wavelengths, carved by jets ploughing through space at a quarter of the speed of light. “The space along the jets path glows brilliantly in high energy x-ray and gamma-ray light tens of light-years away from the black hole, but not visible to the naked eye,” says Mac Intyre.

SS 433 is so powerful astrophysicists have been searching for high-energy gamma-ray radiation from the area. In the late 1990s, Safi-Harb proposed that this system accelerates particles to energies higher than what can be achieved in the most powerful particle accelerators on Earth. It took nearly 20 years for high-energy gamma-ray radiation to be detected; in 2018 researchers at the High-Altitude Water Cherenkov Observatory announced the discovery of high-energy TeV (Tera-electron-volts) gamma-rays from the system. However, the site of particle acceleration could not be pinpointed until now.

Kaya Mori

Kaya Mori

Using the European Space Agency’s XMM-Newton satellite and NASA’s NuSTAR satellite, modern orbiting x-ray telescopes, combined with data obtained from NASA’s Chandra x-ray telescope, this team of researchers were able to pinpoint the location of the ‘hardest’ (or highest energy) X-ray emitting region near SS 433, believed to be the onset of the eastern jet emission on large scales.

Dr. Kaya Mori, collaborator and astrophysicist from Columbia University in New York, says this powerful energy source, now believed to accelerate particles to very high energies, is a strong candidate for a cosmic “PeVatron,” a source that is accelerating cosmic rays up to Peta-electron volt energies, or 1,000,000,000,000,000 volts!

“Given the unusual nature of the spectrum and source location, this discovery challenges the theory of particle acceleration and points to injection and re- energization of the SS 433 jets at large distances, nearly 100 light years away from the black hole,” says Safi-Harb.

She adds: “SS 433 teaches us about, and zooms-in on, the rare case of a supernova remnant powered by a black hole, microquasars, ultra-luminous X-ray sources (a growing class of X-ray emitting sources whose nature is being debated) and is a micro-version of an active galaxy!”

Matthew Band

Matthew Band

This work involved several students from the University of Manitoba and Columbia University, such as Matthew Band, an undergraduate summer research awardee from UM’s Price Faculty of Engineering, who is a co-author on the paper.

“I didn’t expect my summer work to be apart of something like this, I am thrilled,” he said. “It’s an honour to learn from such great people and be a member of this international collaboration.”

The researchers announced the discovery in a paper published in the Astrophysical Journal, to be shortly presented at the International Symposium on High-Energy Gamma-Ray Astronomy in Barcelona.

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James Bardeen, an expert in solving Einstein's equations, has died at the age of 83 –



James Bardeen, who helped elucidate the properties and behavior of black holes, paving the way for what has been called the golden age of black hole astrophysics, died on June 20 in Seattle. He was 83 years old.

His son William said the cause was cancer. Dr. Bardeen, professor emeritus of physics at the University of Washington, was living in a nursing home in Seattle.

Dr. Bardeen was a descendant of a famous family of physicists. His father is John Twice won the Nobel Prize in Physics, for the invention of the transistor and the theory of superconductivity; his brother, Williaman expert in quantum theory at the Fermi National Accelerator Laboratory in Illinois.

Dr. Bardeen was an expert in solving equations of Einstein’s general theory of relativity. This theory attributes what we call gravity to the curvature of spacetime with matter and energy. Its most mysterious and disturbing consequence has been the possibility of black holes, places so dense that they become endless one-way exit ramps from the universe, swallowing even light and time.

Dr. Bardeen will find the work of his life investigating those mysteries, as well as related mysteries about the evolution of the universe.

said Michael Turner, a cosmologist and professor emeritus at the University of Chicago, who described Dr. Bardeen as a “gentle giant.”

James Maxwell Bardeen was born in Minneapolis on May 9, 1939. His mother, Jane Maxwell Bardeen, was a zoologist and high school teacher. After his father’s business, the family moved to Washington, D.C.; To the Summit, NJ; Then to Champaign-Urbana, Illinois, where you graduate from University of Illinois High School Laboratory.

He attended Harvard University and graduated with a degree in physics in 1960, despite his father’s advice that biology was the wave of the future. “Everyone knows who my father is,” he said in an oral history interview recorded by the Federal University of Paraguay in 2020, adding that he did not feel the need to compete with him. “It was impossible anyway,” he said.

Work under the supervision of a physicist Richard Feynman And an astrophysicist William Fowler (who would both become Nobel Prize laureates), Dr. Bardeen received his Ph.D. He received his Ph.D. from the California Institute of Technology in 1965. His thesis was on the structure of supermassive stars millions of times the mass of the Sun. Astronomers are beginning to suspect that they are the source of the massive energies of quasars detected in the cores of distant galaxies.

After holding postdoctoral positions at the California Institute of Technology and the University of California, Berkeley, he joined the Department of Astronomy at the University of Washington in 1967. An enthusiastic hiker and mountaineer, he was drawn to the school by its easy access to the outdoors.

By then, what a Nobel Prize winner Cape Thorne, a professor at the California Institute of Technology, points out that the golden age of black hole research was in full swing, and Dr. Bardeen was swept up in international meetings. At one, in Paris in 1967, he met Nancy Thomas, a Connecticut high school teacher who was trying to improve her French. They married in 1968.

In addition to his son William, a senior vice president and chief strategy officer of The New York Times Company, and his brother William, Dr. Bardeen’s wife survives him, along with another son, David, and two grandchildren. Sister Elizabeth Gretke passed away in 2000.

attributed to him…Eduardo Braniff

Dr. Bardeen was a member of the National Academy of Sciences as well as his brother and father.

Although he was fast at math, Dr. Bardeen didn’t write faster than he spoke. William Price, a former student of Dr. Thorne now at the University of Texas, remembers being sent to Seattle to finish a paper Dr. Bardeen was supposed to write. Nothing is written. Dr. Bardeen’s wife then ordered the two to sit at opposite ends of the sofa with a sheet. Dr. Bardeen would write a sentence and pass the paper on to Dr. Press, who would either reject it or approve it and then put the pillow back. Dr. Bryce said that each sentence took a few minutes. It took them three days, but the paper was written.

One of the historical moments in those years was the month-long “Summer School” in Les Hoechs, France, in 1972 that included all the eminent black hole scientists. Dr. Bardeen was one of six invited speakers. It was during that meeting, Stephen Hawking from the University of Cambridge and Brandon Carternow from the Paris Observatory, wrote a landmark paper called “The Four Laws of Black Hole Mechanics,” which became a springboard for future work, including Dr. Hawking’s surprising calculation that black holes can leak and eventually explode.

In another famous account that same year, Dr. Bardeen deduced the shape and size of a black hole’s “shadow” as seen against a field of distant stars – a circle of light surrounding dark space.

Dr. Thorne said the shape was made famous by the Event Horizon Telescope observations of black holes in the galaxy M87 and at the center of the Milky Way, and by visualizations in the movie “Interstellar.”

Cosmology was among Dr. Bardeen’s other interests. In a 1982 paper, he, Dr. Turner and Paul Steinhardt of Princeton described how submicroscopic fluctuations in matter and energy density in the early universe would grow and give rise to the pattern of galaxies we see in the sky today.

Dr. Turner said, “Jim was glad we used his formalities, and he was sure we got it right.”

Dr. Bardeen transferred to Yale University in 1972. After four years, dissatisfied with the academic bureaucracy in the East and anxious abroad again, he returned to the University of Washington. Retired in 2006.

But it did not stop working. Dr. Thorne recounted a recent telephone conversation in which they recalled the hiking and camping trips they used to take with their families. In the same conversation, Dr. Bardeen described the last thoughts he had about what happens when a black hole evaporates, noting that it might turn into a white hole,

“This was one aspect of Jim in a nutshell, thinking deeply about physics in new creative ways until the end of his life,” Dr. Thorne wrote in an email.

“Reader. Infuriatingly humble coffee enthusiast. Future teen idol. Tv nerd. Explorer. Organizer. Twitter aficionado. Evil music fanatic.”

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Astronaut study reveals effects of space travel on human bones – The Jakarta Post – The Jakarta Post



Will Dunham (Reuters)

Washington, United States   ●  
Mon, July 4, 2022

Science & Tech

A study of bone loss in 17 astronauts who flew aboard the International Space Station is providing a fuller understanding of the effects of space travel on the human body and steps that can mitigate it, crucial knowledge ahead of potential ambitious future missions.

The research amassed new data on bone loss in astronauts caused by the microgravity conditions of space and the degree to which bone mineral density can be regained on Earth. It involved 14 male and three female astronauts, average age 47, whose missions ranged from four to seven months in space, with an average of about 5-1/2 months.

A year after returning to Earth, the astronauts on average exhibited 2.1% reduced bone mineral density at the tibia – one of the bones of the lower leg – and 1.3% reduced bone strength. Nine did not recover bone mineral density after the space flight, experiencing permanent loss.

“We know that astronauts lose bone on long-duration spaceflight. What’s novel about this study is that we followed astronauts for one year after their space travel to understand if and how bone recovers,” said University of Calgary professor Leigh Gabel, an exercise scientist who was the lead author of the research published this week in the journal Scientific Reports.

“Astronauts experienced significant bone loss during six-month spaceflights – loss that we would expect to see in older adults over two decades on Earth, and they only recovered about half of that loss after one year back on Earth,” Gabel said.

The bone loss occurs because bones that typically would be weight-bearing on Earth do not carry weight in space. Space agencies are going to need to improve countermeasures – exercise regimes and nutrition – to help prevent bone loss, Gabel said.

“During spaceflight, fine bone structures thin, and eventually some of the bone rods disconnect from one another. Once the astronaut comes back to Earth, the remaining bone connections can thicken and strengthen, but the ones that disconnected in space can’t be rebuilt, so the astronaut’s overall bone structure permanently changes,” Gabel said.

The study’s astronauts flew on the space station in the past seven years. The study did not give their nationalities but they were from the U.S. space agency NASA, Canadian Space Agency, European Space Agency and Japan Aerospace Exploration Agency.

Space travel poses various challenges to the human body – key concerns for space agencies as they plan new explorations. For instance, NASA is aiming to send astronauts back to the moon, a mission now planned for 2025 at the earliest. That could be a prelude to future astronaut missions to Mars or a longer-term presence on the lunar surface.

“Microgravity affects a lot of body systems, muscle and bone being among them,” Gabel said.

“The cardiovascular system also experiences many changes. Without gravity pulling blood towards our feet, astronauts experience a fluid shift that causes more blood to pool in the upper body. This can affect the cardiovascular system and vision.

“Radiation is also a large health concern for astronauts as the further they travel from Earth the greater exposure to the sun’s radiation and increased cancer risk,” Gabel said.

The study showed that longer space missions resulted both in more bone loss and a lower likelihood of recovering bone afterward. In-flight exercise – resistance training on the space station – proved important for preventing muscle and bone loss. Astronauts who performed more deadlifts compared to what they usually did on Earth were found to be more likely to recover bone after the mission.

“There is a lot we still do not know regarding how microgravity affects human health, particularly on space missions longer than six months, and on the long-term health consequences,” Gabel said. “We really hope that bone loss eventually plateaus on longer missions, that people will stop losing bone, but we don’t know.”

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