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The size of newborn neutron stars determined by astrophysicists

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Chinese and Australian astrophysicists have discovered that neutron stars’ birth rates can be described by a unimodal distribution that smoothly turns on at a solar mass of 1.1 and peaks before declining as a sudden power method.

Impressions of the artist of Neutron Star. Image credit: Sci.News.

Neutron stars are dense remnants of giant stars, more than eight times as huge remnants as our Sun, born at the end of life with the explosion of a brilliant supernova.

These incredibly dense objects have a mass of one to twice the mass of the sun, compressed into a ball of the size of a city with a radius of just 10 km.

Astronomers usually only weigh the neutron stars (which measure how big they are) and are found in binary star systems with different objects, such as white d stars or other neutron stars.

However, in these systems, the first born neutron stars acquire extra mass from their peers through a process called attachment, making it difficult to determine the original birth amount.

“Understanding the birth mass of neutron stars is key to unlocking the history of their formation,” says Dr. Simon Stevenson, an Ozgrav researcher at Swinburne University.

“This work provides an important basis for interpreting gravitational wave detection in neutron star mergers.”

Dr. Stevenson and his colleagues analyzed samples of 90 neutron stars in the binary star system and considered the masses obtained from the birth of each neutron star to measure the distribution of neutron star masses at birth.

They discovered that neutron stars are usually born with a mass of about 1.3 solar masses, with heavier neutron stars being more rare.

“Our approach allows us to finally understand the mass of neutron stars at birth. This has been a long-standing question in astrophysics,” said Professor Xingjiang Zhu of Beijing Normal University.

“This discovery is important for interpreting new observations of neutron star masses from observations of gravitational waves.”

study It will be displayed in the journal Natural Astronomy.

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ZQ. you et al. Determination of the birth mass function of neutron stars from observations. Nut AthlonPublished online on February 26th, 2025. doi:10.1038/s41550-025-02487-w

Source: www.sci.news

Paleontologists have determined that complex life originated 2.1 billion years ago.

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Scientists have widely accepted that complex life first appeared on Earth around 635 million years ago (during the Ediacaran Period). However, an international team of paleontologists from Cardiff, Toulouse and Poitiers universities and China Nonferrous Metals (Guilin) ​​Geological Mining Co., Ltd. has discovered evidence of a much older ecosystem more than 1.5 billion years ago in the Franceville Basin near Gabon on the Atlantic coast of Central Africa.

Artist's impression of a lobe-like macrofossil that lived in a shallow inland sea formed by the collision of two continents 2.1 billion years ago. Image by Abderrazak El Albani, University of Poitiers.

“The availability of phosphorus in the environment is thought to have been a key factor in the evolution of life on Earth, particularly in the transition from simple single-celled organisms to complex organisms such as animals and plants,” said Dr Ernest Chi-Ful, from Cardiff University.

“We already know that elevated marine phosphorus and oxygen concentrations in seawater are linked to an evolutionary event about 635 million years ago.”

“Our study adds an even older event to the record, going back 2.1 billion years.”

Scientists have widely debated the validity of the fossils of megafauna from the Ediacaran period, the oldest of their kind in the geological record.

But Dr Chi Hulu and his colleagues identified a link between changes in the environment before their emergence and increased nutrients, which may have triggered their evolution.

Geochemical analysis of marine sedimentary rocks dating back 2.1 billion years has shed new light on this unusually large fossil assemblage in the Franceville Basin.

A 2.1 billion year old lobe-like macrofossil from the Franceville Basin. Image by Abderrazak El Albani, University of Poitiers.

“We think that after the Congo and San Francisco cratons collided and sutured together, undersea volcanoes further restricted water in this area and even cut it off from the global oceans, forming a nutrient-rich shallow inland marine sea,” Dr Chi-Hulu said.

“This created a localized environment of abundant cyanobacterial photosynthesis for extended periods, leading to oxygenation of local ocean waters and the generation of large food resources.”

“This would have provided enough energy to fuel the increased body size and more complex behaviors seen in the primitive, simple animal-like life forms found in fossils from this period.”

However, the restricted nature of this body of water, combined with the harsh conditions that existed beyond this environmental boundary for billions of years afterward, likely prevented these enigmatic life forms from colonizing the entire planet.

The study suggests that these observations may indicate a two-stage evolution of complex life on Earth.

Step 1 followed the first significant increase in atmospheric oxygen content 2.1 billion years ago, and step 2 followed a second increase in atmospheric oxygen levels about 1.5 billion years later.

“While the first attempt failed to catch on, the second attempt led to the creation of the diversity of animals seen on Earth today,” Dr Chi Hulu said.

of result Published in the journal Precambrian Studies.

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Ernest Chi-Ful others2024. Hydrothermal seawater eutrophication triggers a localized macrobiological experiment in the 2100 Ma Paleoproterozoic Franceville Subbasin. Precambrian Studies 409: 107453; doi: 10.1016/j.precamres.2024.107453

Source: www.sci.news

What’s the real health impact of supermarket bread, as determined by obesity experts

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When discussing diet and nutrition, opinions can often be divisive and passionate. Recently, I found myself in the middle of a debate surrounding supermarket bread that sparked unexpected backlash.

The controversy began after I wrote an article on “ultra-processed foods” (UPF). These foods are products of industrial processes that are difficult to replicate at home, including sweetened drinks, prepackaged foods, and most supermarket breads. In the UK, around 50% of our daily calories come from UPF (source).

UPF has garnered a negative reputation for several reasons. Firstly, these foods tend to be low in protein and fiber, making them easily digestible and calorically dense. Secondly, the processing of UPF often strips away natural flavors, leading to high amounts of added sugar, salt, and fat to enhance taste. Lastly, there are concerns that excessive consumption of UPF may lead to various health issues (British Medical Journal).

While the negative effects of UPF are well-documented, the term itself is vague, encompassing a wide range of foods from heavily processed items to minimally altered products like mass-produced supermarket bread.

In a response to my article, it was argued that real sourdough bread made through lactobacterial fermentation may offer health benefits that are lacking in supermarket bread. It was also noted that supermarket bread tends to be higher in salt and sugar, leading to potential weight gain.

While artisanal sourdough may provide some advantages over supermarket bread, it’s essential to consider the accessibility of such premium products to a broader demographic.

A balanced discussion on the prevalence of UPF in our food supply is necessary, but the demonization of supermarket bread, a staple for many households, may be unwarranted without substantial evidence of harm.

Source: www.sciencefocus.com