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Researchers account for some of the lithium missing from our universe – Phys.org

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Experimental setup. As a beam of beryllium comes in from the left, the deuteron Trojan horse intercepts it at the target and delivers its neutron soldier. This allows the decay products of the beryllium and neutron reactions to be captured by a curved array of six detectors on the right. Credit: Hayakawa et al.

There is a significant discrepancy between theoretical and observed amounts of lithium in our universe. This is known as the cosmological lithium problem, and it has plagued cosmologists for decades. Now, researchers have reduced this discrepancy by around 10%, thanks to a new experiment on the nuclear processes responsible for the creation of lithium. This research could point the way to a more complete understanding of the early universe.

There is a famous saying that “in theory, theory and practice are the same. In practice, they are not.” This holds true in every academic domain, but it’s especially common in cosmology, the study of the entire universe, where what we think we should see and what we really see doesn’t always match up. This is largely because many cosmological phenomena are difficult to study due to inaccessibility. Cosmological phenomena are usually out of our reach because of the extreme distances involved, or often they have occurred before the had even evolved to worry about them in the first place—such is the case with the big bang.

Project Assistant Professor Seiya Hayakawa and Lecturer Hidetoshi Yamaguchi from the Center for Nuclear Study at the University of Tokyo, and their international team are especially interested in one area of cosmology where theory and observation are very misaligned, and that is the issue of the missing lithium, the (CLP). In a nutshell, theory predicts that in the minutes following the big bang that created all matter in the cosmos, there should be an abundance of lithium around three times greater than what we actually observe. But Hayakawa and his team accounted for some of this discrepancy and have thus paved the way for research that may one day resolve it entirely.

“13.7 billion years ago, as matter coalesced from the energy of the , common light elements we all recognize—hydrogen, helium, lithium and beryllium—formed in a process we call Big Bang nucleosynthesis (BBN),” said Hayakawa. “However, BBN is not a straightforward chain of events where one thing becomes another in sequence; it is actually a complex web of processes where a jumble of protons and neutrons builds up atomic nuclei, and some of these decay into other nuclei. For example, the abundance of one form of lithium, or isotope—lithium-7—mostly results from the production and decay of beryllium-7. But it has either been overestimated in theory, underobserved in reality, or a combination of the two. This needs to be resolved in order to really understand what took place way back then.”

Lithium-7 is the most common isotope of lithium, accounting for 92.5% of all observed. However, even though the accepted models of BBN predict the relative amounts of all elements involved in BBN with extreme accuracy, the expected amount of lithium-7 is around three times greater than what is actually observed. This means there is a gap in our knowledge about the formation of the early universe. There are several theoretical and observational approaches which aim to resolve this, but Hayakawa and his team simulated conditions during BBN using particle beams, detectors and an observational method known as the Trojan horse.

“We scrutinized more than ever before one of the BBN reactions, where beryllium-7 and a decay into lithium-7 and a proton. The resulting levels of -7 abundance were slightly lower than anticipated, about 10% lower,” said Hayakawa. “This is a very difficult reaction to observe since beryllium-7 and neutrons are unstable. So we used deuteron, a hydrogen nucleus with an extra neutron, as a vessel to smuggle a neutron into a beryllium-7 beam without disturbing it. This is a unique technique, developed by an Italian group we collaborate with, in which the deuteron is like the Trojan horse in Greek myth, and the neutron is the soldier who sneaks into the impregnable city of Troy without tipping off the guards (destabilizing the sample). Thanks to the new experimental result, we can offer future theoretical researchers a slightly less daunting task when trying to resolve the CLP.”


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The universe has a lithium problem


More information:
S. Hayakawa et al, Constraining the Primordial Lithium Abundance: New Cross Section Measurement of the 7Be + n Reactions Updates the Total 7Be Destruction Rate, The Astrophysical Journal Letters (2021). DOI: 10.3847/2041-8213/ac061f

Citation:
Researchers account for some of the lithium missing from our universe (2021, July 1)
retrieved 1 July 2021
from https://phys.org/news/2021-07-account-lithium-universe.html

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Elon Musk's SpaceX saved NASA $500 million – Quartz

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The rocket billionaire discourse, heady as it is, can distract from the facts. Here’s one: NASA saved at least $548 million, and perhaps more, thanks to just one contract with Elon Musk’s SpaceX.

Last week, the US space agency tapped the company’s Falcon Heavy rocket to launch a space probe to one of Jupiter’s moons, Europa, in 2024. The much-awaited Europa Clipper mission will fly by and assess the evidence of water—and extra-terrestrial life—on the astronomical body. The mission was driven through Congress thanks in large part to the support of one former representative, John Culberson, a Texas Republican who navigated it through the sea of veto points and competing priorities that often stands between scientific hopes and their realization.

One way the mission avoided political pitfalls was a linkage with Boeing’s Space Launch System (SLS) rocket, a huge space vehicle designed to return humans to the moon or Mars. The rocket had just one problem: It was hastily assembled from the remains of a canceled NASA program, and there were no concrete plans for it. A decade ago, the folks behind each project joined forces to justify one another’s work. “Once built, SLS would be a rocket with nowhere to fly,” David W. Brown writes in The Mission, his account of the project. “Europa was a somewhere.”

The delayed SLS has yet to fly. Its first mission is expected around the end of this year. But since the SLS became central to the Trump administration’s Artemis program to return to the moon, NASA auditors have pointed out, in addition to the massive cost, that there would not be enough SLS rockets for both the moon and Europa missions.

In 2019, NASA’s inspector general sounded out the possibilities (pdf), and wasn’t bullish on any of them, particularly on price: Even accounting for the fact that the SLS could get the probe to Jupiter faster (saving money spent on the program back home), the system would cost about $726 million. Two other rockets available for purchase, the United Launch Alliance’s Delta IV and the Falcon Heavy, were forecast to cost $450 million each.

The Europa Clipper wound up with a cheaper ride

The deal NASA eventually made with SpaceX for the Falcon Heavy, however, will cost just $178 million. The drop in cost is directly traceable to SpaceX’s approach to designing reusable rockets, and to the partnership NASA struck with Musk’s space firm in its early days.

Think about that: In just two years, the price of launching a space probe fell by 75%; it’s less than the cost of the rocket that launched the latest Mars rover last year. This will enable NASA to direct more resources to other science programs (as well as getting the SLS off the ground).

“Having that launch capability at that price point just saves so much, particularly for the science part of NASA that just does not have the mega-budgets that human spaceflight does,” says Casey Dreier, a space policy analyst at the Planetary Society. “To see other future missions by NASA able to leverage the lift capability of the Heavy at that price point opens up a significant amount of space access.”

The Falcon Heavy, which didn’t even exist when the Europa mission was being planned, has only flown three times. But it will launch at least five more times, including for a NASA mission to an asteroid called Psyche, before the Europa mission is expected to get underway in late 2024.

This is a transformative period for the maturing space industry, as billionaire funders and new business models increase the capacity of private actors. The egos involved may take up a lot of oxygen, but the goals of the commercial space business are not mutually exclusive with NASA’s scientific pursuits; quite the opposite, in fact: They’re enabling more science than before.

A version of this story originally appeared in Quartz’s Space Business newsletter.

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International Space Station Gets Unplanned Shove as Russian Module Arrives – BNN

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(Bloomberg) — The International Space Station got an unplanned push when the thrusters on a new Russian module turned on unexpectedly after docking.

The movements caused a brief loss of attitude control but the space station suffered no damage and none of the seven crew members was injured, ISS flight controllers in Houston said on NASA TV. The U.S National Aeronautics and Space Administration is planning a news conference later Thursday to discuss the incident. 

The mishap occurred a day before Boeing Co. was scheduled to launch its Starliner capsule on a test flight to the orbiting lab as part of NASA’s Commercial Crew Program. The Boeing mission is a do-over of a botched test from December 2019 and the Starliner won’t be carrying a crew on the flight, which is scheduled to blast off from Florida at 2:53 p.m. Eastern time on Friday.

NASA is “monitoring the impact to tomorrow’s launch of the Boeing Starliner spacecraft,” according to a statement by the space agency.

Russian cosmonauts had opened the new Nauka module’s hatch and were incorporating its computers with the existing Zvedza service module when the newly arrived spacecraft began firing at 12:45 p.m. Eastern. The thruster firings changed the station’s attitude by 45 degrees, NASA said. 

A Russian Progress cargo craft attached to the station began firing its own thrusters to counteract the effect from the Nauka module. Roscosmos flight controllers planned to reconfigure the Nauka thrusters to prevent a recurrence, NASA said. The U.S. space agency and Russia are investigating why the unplanned thrusting occurred. 

(Updates with NASA comment in fourth paragraph. A previous version of this story corrected the time in the fifth paragraph.)

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Sponge-like fossils discovered in Northwest Territories may be evidence of oldest animal on Earth – National Post

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The fossil, the study says, predates the known timeline of animal evolution on Earth by 350 million years

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Fossils found in rugged mountainous terrain in Canada’s Northwest Territories may give a glimpse at the humble dawn of animal life on Earth — sea sponges that inhabited primordial reefs built by bacteria roughly 890 million years ago.

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A Canadian researcher said on Wednesday the fossils, dating to a time called the Neoproterozoic Period, appear to show distinctive microstructures from the body of a sea sponge built similarly to a species living today called the Mediterranean bath sponge, or Spongia officinalis.

If this interpretation is correct, these would be the oldest fossils of animal life by roughly 300 million years.

“The earliest animals to emerge evolutionarily were probably sponge-like. This is not surprising given that sponges are the most basic type of animal both today and in the fossil record,” said geologist Elizabeth Turner of Laurentian University in Canada, who conducted the study published in the journal Nature.

The Earth formed more than 4.5 billion years ago. The first life forms were bacteria-like single-celled marine organisms that arose hundreds of millions of years later. Complex life evolved relatively late in Earth’s history.

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The first appearance of rudimentary animal life has been a much-debated topic in terms of its timing and form. An enigmatic ribbed, pancake-shaped organism called Dickinsonia known from fossils dating to roughly 575 million years ago has been considered a candidate as the earliest-known animal.

The earliest animals to emerge evolutionarily were probably sponge-like

Turner said she believes animals evolved much earlier than the present fossil record indicates.

“The existence of a protracted back-history is not surprising, but the sheer duration of it — a few hundred million years — may be a little unexpected for some researchers,” Turner said.

When people think of animals, a sponge may not immediately come to mind. But sponges — aquatic invertebrates that live fixed to the sea floor and possess soft, porous bodies with internal skeletons — are among the most successful animal groups.

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“They lack a nervous, digestive and circulatory system. They have an amazing water-pumping machine, produced by specialized cells, that they use to move seawater through their bodies to filter-feed,” Turner said.

Some sponges have skeletons made of microscopic rods of quartz or calcite. Others have skeletons made of a tough protein called spongin that forms a complex three-dimensional meshwork supporting the animal’s soft tissue. The Canadian fossils represent this latter kind, called a horny sponge.

“It is the relict structure of the 3-D meshwork spongin skeleton that is preserved and that is so distinctive,” Turner said.

This structure, visible under the microscope, consists of tiny tubes that branch and rejoin to form the meshwork. The body size for the sponge would have been roughly four-tenths of an inch (1 cm). Turner said the sponges appear to have lived in cavities just below the reef surface and in surface depressions.

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Fossil pattern of the ancient sponge (L) compared to that of a modern sponge (R)
Fossil pattern of the ancient sponge (L) compared to that of a modern sponge (R) Photo by Nature

If these fossils genuinely show a type of sponge, their age would indicate that Earth’s first animals evolved before a pair of landmark events usually seen as predating animal life.

One of these was the second of two episodes in the planet’s history when the amount of atmospheric oxygen greatly increased, sometime between about 830 and 540 million years ago. The other was a tremendously cold time when Earth may have been encased in ice or at least partially frozen over, sometime between about 720 and 635 million years ago.

The fossils predate by about 350 million years what had been the oldest-known sponge fossils. Turner noted that genetic research indicates that sponges first appeared at approximately the time to which these fossils date.

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