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International Space Station facing irreparable failures, Russia warns – BBC News

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Reuters

The International Space Station (ISS) could suffer “irreparable” failures due to outdated equipment and hardware, a Russian official has warned.

At least 80 percent of in-flight systems on the Russian segment of the ISS had passed their expiry date, Vladimir Solovyov told state media.

He also said small cracks had been discovered that could worsen over time.

Russia has often raised concerns over hardware and has suggested it could leave the ISS after 2025.

The station was built in 1998 as part of a joint project between Russia, America, Canada, Japan and several European countries and was originally designed for a 15-year lifespan.

Mr Solovyov, the chief engineer at the space company Energia, which is the leading developer of Russia’s section of the ISS, said: “Literally a day after the [in-flight] systems are fully exhausted, irreparable failures may begin.”

He warned last year that much of the equipment on the station was starting to age and would soon need to be replaced.

The former cosmonaut also announced that “superficial” cracks had been discovered on Russia’s Zarya cargo module. Launched in 1998, it is one of the oldest modules of the ISS and is now primarily used for storage.

“This is bad and suggests that the fissures will begin to spread over time,” Mr Solovyov told the RIA news agency.

In April, Russia’s Deputy Prime Minister Yuri Borisov told state TV that aging metal on the station could “lead to irreversible consequences – to catastrophe. We mustn’t let that happen”.

And Roscosmos, the Russian space agency, said last year that structural fatigue meant the ISS would not be capable of operating beyond 2030.

Russia’s space programme has been hit by a series of budget cuts and corruption scandals in recent years. Its section of the ISS has also faced a string of problems.

In July, a malfunction caused the jet thrusters on the country’s Nauka research model to fire without warning, destabilising the ISS.

Its Zvezda service module, which provides living quarters for ISS crew members, has also experienced several air leaks since 2019.

Despite these setbacks, the country’s space agency has promised a series of ambitious ventures, including a mission to Venus, the creation of a rocket capable of making round trips into space and a mission to the Moon’s surface next year.

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Faces of 3 Egyptian mummies revealed for the first time – Editorials 99

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New DNA sequencing technology is giving us a first glimpse at what ancient men looked like — before they were mummies.

Genetic researchers have revealed highly detailed three-dimensional renderings of the faces of three Egyptian men who lived more than 2,000 years ago, using DNA pulled from their mummified remains.

The digital reconstructions show the men at age 25, who were unearthed in the vicinity of the ancient Egyptian city of Abusir el-Meleq, in the south of Cairo. Scientists estimate the men were each buried sometime between 1380 B.C. and A.D. 425, Live Science has reported. Their DNA was previously sequenced in 2017 at the Max Planck institute in Germany — at the time, the first successful reconstruction of an Egyptian mummy’s genome in history.

Since then, researchers at Parabon NanoLabs in Reston, Virginia have used forensic DNA phenotyping to create 3D models of the men’s faces, a process by which genetic data is used to predict facial features and other physical characteristics of the sampled mummy.

“This is the first time comprehensive DNA phenotyping has been performed on human DNA of this age,” Parabon said in a statement

The technology is already being used to solve modern cold cases involving unidentified victims.
Parabon NanoLabs

The lab used a combination of efforts to reconstruct the faces. Some features, including skin and eye color, can be predicted via genetic markers in the individual’s genome, while others are measured through what’s left of their physical remains.

Parabon’s methods revealed that the men had light brown skin with dark eyes and hair, and that the men were more genetically similar to modern-day Mediterranean populations than that of Egypt today.

Their process had to account for the fact that human DNA degrades over time, and is likely to be contaminated by bacterial DNA. In this case, researchers use genetic commonalities between human populations to fill in the gaps of their mummy genome.

Researchers see that this process could eventually be used in contemporary forensics, in order to identify more recent remains of unknown individuals.

Parabon’s work in genetics has already been used to crack 175 cold cases, including nine solved using the methods described in the current study, they told Live Science.

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Some animal species can survive successfully without sexual reproduction: study – CTV News

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TORONTO —
An international team of researchers have found that some animals can survive over very long periods of time — possibly millions of years — without sexual reproduction.

By studying a tiny beetle mite species, just one-fifth of a millimetre in size, scientists found that asexual reproduction can be successful in the long term.

The study authors note that until now, the survival of an animal species over a geologically long period of time without sexual reproduction was considered very unlikely, if not impossible.

Asexual reproduction involves one parent and produces offspring that are genetically identical to each other and the parent, while sexual reproduction involves two parents and produces offspring that are genetically unique.

Using the Oppiella nova beetle mite, an all-female species, researchers from the Universities of Cologne and Göttingen, the University in Lausanne in Switzerland and the University of Montpellier in France, demonstrated for the first time the so-called Meselson effect in animals.

According to the study, the Meselson effect is a characteristic trace in the genome of an organism that suggests “purely asexual reproduction.”

In the study, researchers looked at different populations of the Oppiella nova and the closely related, but sexually reproducing species, Oppiella subpectinata in Germany and sequenced their genomes. The study found that the sequencing of the Oppiella nova genomes showed the Meselson effect.

The findings were published Tuesday in peer-reviewed scientific journal PNAS.

Scientists had previously considered the Oppiella nova species an “ancient asexual scandal” as they couldn’t determine how the beetles were managing to reproduce without having sexual intercourse.

Initially, the study notes that biologists thought these beetles were hiding their acts of reproduction.

“There could be, for example, some kind of ‘cryptic’ sexual exchange that is not known. Or not yet known,” first author of the study Alexander Brandt of the University of Lausanne said in a press release.

“For example, very rarely a reproductive male could be produced after all — possibly even ‘by accident’,” he added.

However, the Oppiella nova beetle mite clones itself rather than reproducing, according to the study.

Researchers say the existence of ancient asexual animal species can be difficult to explain as asexual reproduction can seem “very disadvantageous” in the long term due to a lack of genetic diversity.

Biologists say there is typically an “evolutionary advantage” to having two different genomes that only a pair of parents can supply. Through sexual reproduction, this ensures a “constant ‘mixing’ of the two copies” of the genome in each of their cells.

This means that the two sets of genetic information remain very similar, but there are differences that allow organisms on earth to adapt over time, evolving characteristics that best suit the changing environment.

Researchers also found that it is possible for asexually reproducing species to introduce genetic variance into their genomes and thus adapt to their environment during evolution, despite producing genetic clones of themselves.

Scientists say that lack of “genome mixing” compared to sexual species causes the two genome copies of asexual animals to accumulate separate mutations and evolve independently over time.

While the survival rate of a species without sexual reproduction is quite rare, scientists conclude that it is not impossible.

“Our results clearly show that O. nova reproduces exclusively asexually. When it comes to understanding how evolution works without sex, these beetle mites could still provide a surprise or two,” Jens Bast, junior research group leader at the University of Cologne, said in the press release.

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Footprints prove humans roamed America 23,000 years ago – DodoFinance

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Footprints are the first undisputed evidence that humans have ever been found in the Americas during the so-called Last Ice Maximum.

The researchers write that in the magazine Science. In the center is a decent collection of footprints found in White Sands National Park, located on the southern border of the United States. Dating indicates that the oldest footprints are around 23,000 years old. “This corresponds to the highest point of the last glacier, also called the last glacial maximum, and in fact the oldest footprints we know of in the Americas,” said researcher Kathleen Springer.

Children and adolescents
Judging by their size, the footprints appear to have been left mostly by adolescents and young children. Only a few fingerprints are attributed to adults. People left their marks while digging in the soft mud by a shallow lake. In addition to the 23,000-year-old footprints, somewhat more recent footprints have also been found; together they testify that the people were present here for a period of about 2000 years.

Giant wolves and mammoths
And people weren’t the only ones walking there; Footprints of mammoths, birds, large land sloths and large wolves have also been found in the same area. “This is an important place, because all the traces we found here are testimony to human interaction in a landscape that was also home to extinct animals such as mammoths and land sloths,” said researcher Sally Reynolds. We can see how people and animals coexisted here and dating the footprints also gives us a better idea of ​​what the landscape looked like at the time.

Go out together
But what makes the discovery of these footprints particularly interesting, of course, is that the oldest footprints are no less than 23,000 years old. For years, scientists have been the subject of heated debate about when the first humans arrived in America. It is generally believed that this was not until after the melting of the North American ice caps, around 16,000 years ago. But the footprints prove that people have already set foot in America. “White Sands provides us with the first unequivocal evidence of the presence of humans in the Americas during the last ice maximum,” said researcher Dan Odess.

Important for previous finds
In recent years, there have been tentative indications that humans roamed the Americas already over 16,000 years ago. But these clues were not very convincing on their own. “One of the reasons why this discovery (footprints, note) is so important is that it makes more plausible the idea that other very old sites really indicate the presence of humans – even if the evidence that these sites contain are less convincing. This does not mean that all of these sites are real (and therefore were left behind by humans over 16,000 years ago, editor’s note), but it does mean that we cannot immediately exclude this.

Finally, the engravings also give us a unique glimpse into the life of these first “Americans”. “The footprints left at White Sands give a picture of what happened here,” said researcher Matthew Bennett. “Adolescents interacting with young children and adults. We can see our ancestors as very functional people who engaged in hunting and survival, but what we see here is that they also played and people of different ages came together.

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