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Boeing Starliner lands in New Mexico after aborted space mission – Euronews

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Boeing safely landed its crew capsule in the New Mexico desert Sunday after an aborted flight to the International Space Station that threatened to derail the company’s effort to launch astronauts for NASA next year.

The Starliner descended into the Army’s White Sands Missile Range in the predawn darkness, ending a two-day demo that should have lasted more than a week. All three main parachutes popped open and airbags also inflated around the spacecraft to ease the impact.

“Congratulations, Starliner,” said Mission Control, calling it a successful touchdown.

A test dummy named Rosie the Rocketeer was in the commander’s seat. Also returning were Christmas presents, clothes and food that should have been delivered to the space station crew.

After seeing this first test flight cut short and the space station docking canceled because of an improperly set clock on the capsule, Boeing employees were relieved to get the Starliner back.

Recovery teams cheered as they watched the capsule drift down through the air and make a bull’s- eye landing. The touchdown was broadcast live on NASA TV; infrared cameras painted the descending capsule in a ghostly white.

It was the first U.S. capsule designed for astronauts to return from orbit and land on the ground. NASA’s early crew capsules all had splashdowns. SpaceX’s Dragon capsule, which made its orbital debut last winter, also aims for the ocean at mission’s end.

The astronauts assigned to the first Starliner crew — two from NASA and one from Boeing — were part of the welcoming committee in the bitter cold.

Top NASA and Boeing officials poured into Mission Control in Houston, congratulating everyone on the landing.

The capsule’s first trip to space began with a smooth rocket ride from Cape Canaveral on Friday. But barely a half hour into the flight, it failed to fire its thrusters to give chase to the space station and ended up in the wrong orbit.

The problem was with the Starliner’s internal clock: It did not sync up with the Atlas V rocket, throwing off the capsule’s timing.

The capsule burned so much fuel trying to orient itself in orbit that there wasn’t enough left for a space station rendezvous. Flight controllers tried to correct the problem, but between the spacecraft’s position and a gap in communications, their signals did not get through. They later managed to reset the clock.

Boeing is still trying to figure out how the timing error occurred. The mission lasted nearly 50 hours and included 33 orbits around the Earth.

Last month’s parachute problem turned out to be a quick fix. Only two parachutes deployed during an atmospheric test because workers failed to connect a pin in the rigging.

NASA is uncertain whether it will demand another test flight from Boeing — to include a space station visit — before putting its astronauts on board. Boeing had been shooting for its first astronaut mission in the first half of 2020. This capsule is supposed to be recycled for the second flight with crew.

Despite its own setbacks, SpaceX remains in the lead in NASA’s commercial crew program.

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Paradox-Free Time Travel Is Theoretically Possible, Researchers Say – WBFO

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“The past is obdurate,” Stephen King wrote in his book about a man who goes back in time to prevent the Kennedy assassination. “It doesn’t want to be changed.”

Turns out, King might have been onto something.

Countless science fiction tales have explored the paradox of what would happen if you do something in the past that endangers the future. Perhaps one of the most famous pop culture examples is Back to the Future, when Marty McFly went back in time and accidentally stopped his parents from meeting, putting his own existence in jeopardy.

But maybe McFly wasn’t in much danger after all. According a new paper from researchers at the University of Queensland, even if time travel were possible, the paradox couldn’t actually exist.

Researchers ran the numbers, and determined that even if you make a change in the past, the timeline would essentially self-correct, ensuring that whatever happened to send you back in time would still happen.

“Say you travelled in time, in an attempt to stop COVID-19’s patient zero from being exposed to the virus,” University of Queensland scientist Fabio Costa told the university’s news service.

“However if you stopped that individual from becoming infected — that would eliminate the motivation for you to go back and stop the pandemic in the first place,” said Costa, who co-authored the paper with honors undergraduate student Germain Tobar.

“This is a paradox — an inconsistency that often leads people to think that time travel cannot occur in our universe.”

A variation is known as the “grandfather paradox” — in which a time traveler kills their own grandfather, in the process preventing the time traveler’s birth.

The logical paradox has given researchers a headache, in part because according to Einstein’s theory of general relativity, “closed time-like curves” are possible, theoretically allowing an observer to travel back in time and interact with their past self — and potentially endangering their own existence.

But these researchers say that such a paradox wouldn’t necessarily exist, because events would adjust themselves.

Take the coronavirus patient zero example. “You might try and stop patient zero from becoming infected, but in doing so you would catch the virus and become patient zero, or someone else would,” Tobar told the university’s news service.

In other words, a time traveler could make changes — but the original outcome would still find a way to happen. Maybe not the same way it happened in the first timeline; but close enough so that the time traveler would still exist, and would still be motivated to go back in time.

“No matter what you did, the salient events would just recalibrate around you,” Tobar said.

The paper, “Reversible dynamics with closed time-like curves and freedom of choice,” was published last week in the peer-reviewed journal Classical and Quantum Gravity. The findings seem consistent with another time travel study published this summer in the peer-reviewed journal Physical Review Letters. That study found that changes made in the past won’t drastically alter the future.

Best-selling science fiction author Blake Crouch, who has written extensively about time travel, said the new study seems to support what certain time travel tropes have posited all along.

“The universe is deterministic and attempts to alter Past Event X are destined to be the forces which bring Past Event X into being,” Crouch told NPR via email. “So the future can affect the past. Or maybe time is just an illusion. But I guess it’s cool that the math checks out.”

Copyright 2020 NPR. To see more, visit https://www.npr.org.

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Starship SN8 prepares for test series – First sighting of Super Heavy – NASASpaceflight.com

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Starship SN8 prepares for test series – First sighting of Super Heavy – NASASpaceFlight.com

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Chang'e-4 lander finds radiation levels on the moon 2.6 times higher than at space station – Firstpost

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As the US prepares to return humans to the Moon this decade, one of the biggest dangers future astronauts will face is space radiation that can cause lasting health effects, from cataracts to cancer and neurodegenerative diseases.

Though the Apollo missions of the 1960s and 1970s proved it was safe for people to spend a few days on the lunar surface, NASA did not take daily radiation measurements that would help scientists quantify just how long crews could stay.

This question was resolved Friday after a Chinese-German team published in the journal Science Advances the results of an experiment carried out by China’s Chang’E 4 lander in 2019.

“The radiation of the Moon is between two and three times higher than what you have on the ISS (International Space Station),” co-author Robert Wimmer-Schweingruber, an astrophysicist at the University of Kiel told AFP.

“So that limits your stay to approximately two months on the surface of the Moon,” he added, once the radiation exposure from the roughly week-long journey there, and week back, is taken into account.

There are several sources of radiation exposure: galactic cosmic rays, sporadic solar particle events (for example from solar flares), and neutrons and gamma rays from interactions between space radiation and the lunar soil.

Scientist-astronaut Harrison Schmitt collecting lunar rake samples during the first Apollo 17. Schmitt was the lunar module pilot for the mission. The Lunar Rake is used to collect discrete samples of rocks and rock chips of different sizes. Image courtesy: NASA

Radiation is measured using the unit sievert, which quantifies the amount absorbed by human tissues.

The team found that the radiation exposure on the Moon is 1,369 microsieverts per day – about 2.6 times higher than the International Space Station crew’s daily dose.

The reason for this is that the ISS is still partly shielded by the Earth’s protective magnetic bubble, called the magnetosphere, which deflects most radiation from space.

Earth’s atmosphere provides additional protection for humans on the surface, but we are more exposed the higher up we go.

“The radiation levels we measured on the Moon are about 200 times higher than on the surface of the Earth and five to 10 times higher than on a flight from New York to Frankfurt,” added Wimmer-Schweingruber.

NASA is planning to bring humans to the Moon by 2024 under the Artemis mission and has said it has plans for a long term presence that would include astronauts working and living on the surface.

For Wimmer-Schweingruber there is one work-around if we want humans to spend more than two or three months: build habitats that are shielded from radiation by coating them with 80 centimeters (30 inches) of lunar soil.

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