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Scientists Have Officially Found a Mineral Never Before Seen in Nature – ScienceAlert

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It was found along the side of a road in a remote Australian gold rush town. In the old days, Wedderburn was a hotspot for prospectors – it occasionally still is – but nobody there had ever seen a nugget quite like this one.

The Wedderburn meteorite, found just north-east of the town in 1951, was a small 210-gram chunk of strange-looking space rock that fell out of the sky. For decades, scientists have been trying to decipher its secrets, and researchers just decoded another.

In a study published in August this year, led by Caltech mineralogist Chi Ma, scientists analysed the Wedderburn meteorite and verified the first natural occurrence of what they call ‘edscottite‘: a rare form of iron-carbide mineral that’s never been found in nature.

Since the Wedderburn meteorite’s spacey origins were first identified, the distinctive black-and-red rock has been examined by numerous research teams – to the extent that only about one-third of the original specimen still remains intact, held within the geological collection at Museums Victoria in Australia.

The rest has been taken away in a series of slices, extracted to analyse what the meteorite is made from. Those analyses have revealed traces of gold and iron, along with rarer minerals such as kamacite, schreibersite, taenite, and troilite. Now we can add edscottite to that list.

The edscottite discovery – named in honour of meteorite expert and cosmochemist Edward Scott from the University of Hawaii – is significant because never before have we confirmed that this distinct atomic formulation of iron carbide mineral occurs naturally.

Such a confirmation is important, because it’s a pre-requisite for minerals to be officially recognised as such by the International Mineralogical Association (IMA).

A synthetic version of the iron carbide mineral has been known about for decades – a phase produced during iron smelting.

But thanks to the analysis by Chi Ma and UCLA geophysicist Alan Rubin, edscottite is now an official member of the IMA’s mineral club, which is more exclusive than you might think.

“We have discovered 500,000 to 600,000 minerals in the lab, but fewer than 6,000 that nature’s done itself,” Museums Victoria senior curator of geosciences Stuart Mills, who wasn’t involved with the new study, told The Age.

As for how this sliver of natural edscottite ended up just outside of rural Wedderburn can’t be known for sure, but according to planetary scientist Geoffrey Bonning from Australian National University, who wasn’t involved with the study, the mineral could have formed in the heated, pressurised core of an ancient planet.

Long ago, this ill-fated, edscottite-producing planet could have suffered some kind of colossal cosmic collision – involving another planet, or a moon, or an asteroid – and been blasted apart, with the fragmented chunks of this destroyed world being flung across time and space, Bonning told The Age.

Millions of years later, the thinking goes, one such fragment landed by chance just outside Wedderburn – and our understanding of the Universe is the richer for it.

The findings are reported in American Mineralogist.

A version of this article was first published in September 2019.

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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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NASA’s New Budget for Artemis? $28 Billion – Universe Today

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It’s no exaggeration to say that NASA’s plans to return astronauts to the Moon has faced its share of challenges. From its inception, Project Artemis has set some ambitious goals, up to and including placing “the first woman and next man” on the Moon by 2024. Aside from all the technical challenges that this entails, there’s also the question of budgets. As the Apollo Era taught us, reaching the moon in a few years doesn’t come cheap!

Funding is an especially sticky issue right now because of the fact that we’re in an election year and NASA may be dealing with a new administration come Jan of 2021. In response, NASA announced a budget last week (Mon. Sept 21st) that put a price tag on returning astronauts to the Moon. According to NASA, it will cost taxpayers $28 billion between 2021 and 2025 to make sure Project Artemis’ meets its deadline of 2024.

On the same day during a phone briefing with journalists, NASA Administrator Jim Bridenstine noted that “political risks” are often the biggest obstacle to NASA’s work. This is perhaps a reference to the fact that NASA’s plans and goals have forcible shifted over the past decade or so in response to the changing priorities of new administrations.

Artist’s illustration of the new spacesuit NASA is designing for Artemis astronauts. It’s called the xEMU,, or Exploration Extravehicular Mobility Unit. Image Credit: NASA

When he took office in 2009, President Obama and his cabinet inherited the Constellation Program initiated by the Bush administration in 2005. This program aimed to create a new generation of launch systems and spacecraft to return astronauts to the Moon by 2020 at the latest. However, due to the then-current economic crisis and recommendations that the 2020 deadline could not be reached, it was canceled.

A year later, the Obama administration initiated NASA’s “Journey to Mars,” which picked up much of Constellation’s architecture but shifted the focus to a crewed mission to Mars by the 2030s. By 2017, VP Pence announced that the Trump administration’s focus would be on returning to the Moon within the 2020s. By March of 2019, Project Artemis was officially unveiled and NASA was charged with returning to the Moon in five years.

Approval for this funding now falls to Congress, which will be looking at elections by November 3rd. This year, in addition to deciding who will be president, 434 of the 435 Congressional districts across all 50 US states and 33 class 2 Senate seats will be contested. Come January, NASA could be dealing with an entirely new government.

According to Bridenstine, the first tranche of funding ($3.2 billion) must be approved by Christmas in order for NASA to remain “on track for a 2024 moon landing.” In total, NASA will require a full $16 billion in order to fund the development of the human landing system (HLS) – aka. a lunar lander – that will allow the crew of the Artemis III mission (one man and one woman) to land on the surface of the Moon.

The three top HLS concepts for NASA’s Project Artemis. Credit: NASA

At present, three major companies are competing to see which of their concepts NASA will choose. They include SpaceX, which presented NASA with a modified version of their Starship designed, altered to accommodate lunar landings. Then there’s Alabama-based Dynetics’ Human Landing System (DHLS), a vehicle that will provide both descent and ascent capabilities.

Rounding out the competitors is Blue Origin, meanwhile is collaborating on a design for an Integrated Lander Vehicle (ILV) that will consist of three elements – the descent, transfer, and ascent elements – designed by Blue Origin, Northrop Grumman, and Lockheed Martin, respectively. The winning design will either be integrated with the Orion capsule carrying the crew to the Moon or will launch on its own atop a company rocket.

Bridenstine also took the opportunity to set the record straight regarding where the Artemis III mission would be landing. This was in response to a previous statement he made during an online meeting of the Lunar Exploration Analysis Group (LEAG), which seemed to hint that the Artemis crews might revisit the Apollo sites.

“If you’re going to go to the equatorial region again, how are you going to learn the most?” he said. “You could argue that you’ll learn the most by going to the places where we put gear in the past. There could be scientific discoveries there and, of course, just the inspiration of going back to an original Apollo site would be pretty amazing as well.”

Artist’s impression of surface operations on the Moon. Credit: NASA

During Monday’s phone briefing, however, Bridenstine emphasized that the mission will be heading to the South Pole-Aitken Basin:

“To be clear, we’re going to the South Pole. There’s no discussion of anything other than that. The science that we would be doing is really very different than anything we’ve done before. We have to remember during the Apollo era, we thought the moon was bone dry. Now we know that there’s lots of water ice and we know that it’s at the South Pole.”

Investigations of this ice and other resources will be intrinsic to long-term plans to create the Artemis Base Camp. The current schedule has the Artemis I flight (which will be uncrewed) taking place by November of 2021. This will be the inaugural flight of NASA’s Space Launch System (SLS) flying with the Orion space capsule. Artemis II is scheduled for 2023, and will take a crew of astronauts around the Moon but will not attempt a lunar landing.

In 2024, the long-awaited Artemis III mission will occur and will see astronauts land on the surface for a week of operations and up to five operations on the surface. Beyond 2024, NASA plans to deploy the various segments that make up the Lunar Gateway, which will facilitate more long-term missions to the lunar surface and allow for the construction of the Artemis Base Camp.

Further Reading: Phys.org

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