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First ancient human DNA from islands between Asia and Australia – Mirage News

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Credit: University of Hasanuddin

A research team co-led by Griffith University archaeologists has discovered DNA in the remains of a hunter-gatherer woman who died 7200 years ago on the Indonesian island of Sulawesi. Nicknamed Bessé’, she is the first known skeleton from an early foraging culture called the Toaleans.

Genomic analysis shows that this ancient individual was a distant relative of Aboriginal Australians and Papuans. But it also revealed that Bessé’ is a rare ‘genetic fossil’, in the sense that she belonged to a group with an ancestral history that was unlike that of any previously known human population. 

Excavations at Leang Panninge cave. Credit: Leang Panninge Research Project.

This surprising find, published in the journal Nature, is the first time ancient human DNA has been reported from ‘Wallacea’, the vast group of islands between Borneo and New Guinea and the gateway to the continent of Australia. 

The Sulawesi remains were excavated in 2015 from a cave called Leang Panninge (‘Bat Cave’). They belong to a young female hunter-gatherer who was about 17-18 years old at time of death. She was buried in a foetal position and partially covered by rocks. Stone tools and red ochre (iron-rich rock used to make pigment) were found in her grave, along with bones of hunted wild animals. 

The University of Hasanuddin archaeologists who discovered the woman affectionately dubbed her Bessé’, following a custom among Bugis royal families of bestowing this nickname on newly born princesses before they were formally named.

This is the first relatively complete skeleton to be found alongside securely dated artefacts of the Toalean culture, according to study co-leader Professor Adam Brumm from Griffith’s Australian Research Centre for Human Evolution.

“The Toaleans were early hunter-gatherers who lived a secluded existence in the forests of South Sulawesi from around 8,000 years ago until 1,500 years ago, hunting wild pigs and collecting edible shellfish from rivers,” Professor Brumm said.  

Professor Brumm’s team re-excavated Leang Panninge in 2019 to clarify the context of the burial and collect more samples for dating. Through radiocarbon dating the team was able to constrain the age of Bessé’ to between about 7300 to 7200 years old.

Toalean artefacts have only been found in one small part of Sulawesi, encompassing about 6% of the total land area of the island, the world’s eleventh largest.

“This suggests that this past culture had limited contact with other early Sulawesi communities or people in nearby islands, existing for thousands of years in isolation,” said study co-author Adhi Agus Oktaviana, a researcher in Indonesia’s national archaeological research institute (Pusat Penelitian Arkeologi Nasional) and a doctoral candidate in the Griffith Centre for Social and Cultural Research.

Archaeologists have long debated the origins of the Toaleans. But now analyses of ancient DNA from the inner ear bone of Bessé’ partly confirm existing assertions that Toalean foragers were related to the first modern humans to enter Wallacea some 65,000 years ago, the ancestors of Aboriginal Australians and Papuans. 

“These seafaring hunter-gatherers were the earliest inhabitants of Sahul, the supercontinent that emerged during the Pleistocene (Ice Age) when global sea levels fell, exposing a land bridge between Australia and New Guinea,” Professor Brumm said.

Professor Adam Brumm.

“To reach Sahul, these pioneering humans made ocean crossings through Wallacea, but little about their journeys is known.”

The genomic analyses were led by Selina Carlhoff from the Max Planck Institute for the Science of Human History at Jena, Germany, under the supervision of Professor Cosimo Posth (University of Tübingen) and Professor Johannes Krause (Max Planck Institute for Evolutionary Anthropology, Leipzig).

The results show that Bessé’ shares about half of her genetic makeup with present-day Indigenous Australians and people in New Guinea and the Western Pacific islands. This includes DNA inherited from the now-extinct Denisovans, distant cousins of Neanderthals whose fossils have only been found in Siberia and Tibet. 

“In fact, the proportion of Denisovan DNA in Bessé’ relative to other ancient as well as present-day groups in the region may indicate that the crucial meeting point between our species and Denisovans was in Sulawesi or another Wallacean island,” Professor Posth said.

The research could suggest that ancestors of Bessé’ were among the first modern humans to reach Wallacea, but instead of island hopping eastward to Sahul they remained in Sulawesi.

If so, it may have been the forebears of Bessé’ who created the very old cave paintings found in South Sulawesi. As recently shown by Griffith University researchers, this rock art dates to at least 45,500 years ago and includes what may be the earliest known human representations of animals.  

But analyses also revealed something unexpected in the genome of Bessé’: a deep ancestral signature from an early modern human population of Asian origin. This group did not intermix with the predecessors of Aboriginal Australians and Papuans, suggesting it may have entered the region after the initial peopling of Sahul. 

“It is unlikely we will know much about the identity of these early ancestors of the Toaleans until more ancient human DNA samples are available from Wallacea,” said Indonesian senior author Professor Akin Duli from the University of Hasanuddin.

“But it would now appear that the population history and genetic diversity of early humans in the region were more complex than previously supposed.”

The researchers could detect no ancestry resembling that of Bessé’ in the DNA of people who live in Sulawesi today, who seem to largely descend from Neolithic farmers (‘Austronesians’) who arrived in the region from Taiwan some 3,500 years ago.

This is not unexpected, given that the last traces of Toalean culture vanished from the archaeological record by the fifth century AD. The scientists do note, however, that more extensive genomic sampling of Sulawesi’s diverse population could reveal evidence for the genetic legacy of Toaleans.

“The discovery of Bessé’ and the implications of her genetic ancestry show just how little we understand about the early human story in our region, and how much more there is left to uncover,” Professor Brumm said.

/University Release. This material comes from the originating organization and may be of a point-in-time nature, edited for clarity, style and length. View in full here.

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900-year-old Chinese supernova mystery points to strange nebula – Space.com

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In the year 1181 AD, a new bright point of light as luminous as the planet Saturn appeared to Chinese and Japanese skygazers for a little more than six months before disappearing. Hundreds of years later, researchers believe they have finally found the source of this mysterious appearance.

The event, like the famous Crab Nebula-forming stellar explosion of 1054, is one of just a handful of bright nearby flashes noted in historical records, but unlike the Crab Nebula, the 1181 spectacle was tricky to pin down.

The historical record leaves a few clues that have been useful to modern astronomers. First, the timing: this “guest star” shined for 185 days, from Aug. 6, 1181, to Feb. 6, 1182. The record also indicates its place in the sky, which was a spot located between two Chinese constellations, Chuanshe and Huagai, near the modern Cassiopeia.

Related: Distant ‘Requiem’ supernova will be visible again in 2037, astronomers predict 

These cosmic puzzle pieces led a research team to the ancient flash’s likely culprit: a supernova whose remnants now form a fast-expanding nebula called Pa30. The nebula’s clouds move so quickly that, in the new research, scientists from Hong Kong, the U.K., Spain, Hungary and France found that Pa30’s dust and gas could travel the distance from Earth to the moon in a whopping five minutes. By using that speed and calculating backward, the researchers determined that the nebula would fit a supernova that exploded around 1181.

The team found that Pa30 formed from a rare and relatively faint type of supernova, called a ‘Type Iax supernova.’ “Only around 10% of supernovae are of this type and they are not well understood. The fact that SN1181 was faint but faded very slowly fits this type,” Albert Zijlstra, an astrophysicist at the University of Manchester in the U.K., said in a statement about the new research. 

False-color images of Parker’s star and the nebula Pa30, which scientists now believe are connected with reports of a supernova seen in 1181. (Image credit: The University of Hong Kong)

Scientists also found that Parker’s star, one of the hottest stars in the Milky Way, is also a likely counterpart to the supernova. The nebula and the star are thought to be the result of a massive collision and subsequent merger of two dim stellar corpses known as white dwarfs

“This is the only Type Iax supernova where detailed studies of the remnant star and nebula are possible,” Ziljlstra added. “It is nice to be able to solve both a historical and an astronomical mystery.”

The study was published on Wednesday (Sept. 15) in the journal Astrophysical Journal Letters. 

Follow Doris Elin Urrutia on Twitter @salazar_elin. Follow us on Twitter @Spacedotcom and on Facebook. 

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SpaceX's tourist crew 'healthy, happy and resting' – Phys.org

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Graphic on the four all-civilian passengers on SpaceX’s mission to orbit around the Earth, lauched September 15 from Florida.

SpaceX’s all-civilian Inspiration4 crew are “healthy, happy and resting comfortably,” the company said Thursday in its first update since the pioneering mission blasted off from Cape Canaveral the night before.

The four American space tourists “traveled 5.5 times around Earth, completed their first round of scientific research, and enjoyed a couple of meals” before going to bed, Elon Musk’s company said.

Musk tweeted that he had personally spoken with the crew and “all is well.”

After waking up, they will get their first look out of the Dragon ship’s cupola—a large observation dome that has been fitted onto the vessel for the first time, in place of a docking mechanism.

Billionaire Jared Isaacman, physician assistant Hayley Arceneaux, geoscientist Sian Proctor and aerospace data engineer Chris Sembroski are orbiting the globe at an altitude that at times reaches 590 kilometers (367 miles).

That is deeper in space than the International Space Station, which orbits at 420 kilometers (260 miles), and the furthest any astronauts have ventured from our planet since a 2009 maintenance mission for the Hubble telescope.

The mission aims to raise $200 million for St Jude’s Children’s Research Hospital, and study the biological effects of deep space on the astronauts’ bodies.

Its main goal, however, is to prove that space is accessible to as the United States and like SpaceX seek to further commercialize the cosmos.

The space adventure bookends a summer marked by the battle of the billionaires Richard Branson and Jeff Bezos to reach the final frontier.

But these flights only offered a few minutes of weightlessness—rather than the three full days of orbit the Inspiration4 crew will experience, before splashing down off the coast of Florida on Saturday.


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In first, SpaceX to send all-civilian crew into Earth orbit


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A 900-year-old cosmic mystery has been solved by astronomers – CTV News

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TORONTO —
The mystery behind the origins of a supernova first spotted by 12th-century Chinese and Japanese astronomers has been solved, according to an international team of 21st-century astronomers.

New research, published Wednesday in The Astrophysical Journal, has linked astronomical reports from more than 800 years ago with a faint, fast-expanding nebula surrounding Parker’s Star, one of the hottest stars in the Milky Way galaxy.

The nebula, dubbed Pa30, fits the profile, location and age of the supernova, which was originally documented in 1181 AD.

“The historical reports place the guest star between two Chinese constellations, Chuanshe and Huagai,” Albert Zijlstra, astrophysics professor at the University of Manchester, said in a news release. “Parker’s Star fits the position well. That means both the age and location fit with the events of 1181.”

The first astronomers to lay eyes on the supernova, referred to as SN 1181, described it being as bright as the planet Saturn and remaining visible for six months, the authors of the study said.

Previous research has suggested Parker’s Star and the Pa30 nebula may be the result of the merging of two white dwarf stars. Such events are thought to lead to a rare and faint type of supernova called a “Type Iax” supernova.

“Only around 10 per cent of supernovae are of this type and they are not well understood. The fact that SN 1181 was faint but faded very slowly fits this type,” Zijlstra said. “It is the only such event where we can study both the remnant nebula and the merged star, and also have a description of the explosion itself.”

The key to unlocking the mystery of this historical supernova was the discovery that the Pa30 nebula is expanding at a velocity of more than 1,100 kilometres per second. From this, researchers were able to calculate the nebula’s age to be around 1,000 years old, which coincides with the events of 1181 AD.

“Combining all this information such as the age, location, event brightness and historically recorded 185-day duration, indicates that Parker’s Star and Pa30 are the counterparts of SN 1181,” Zijlstra said. “This is the only Type Iax supernova where detailed studies of the remnant star and nebula are possible.”

There have been five supernovae in the Milky Way in past millennium, and up until now, SN 1181 was the only one whose origins remained unknown.

“It is nice to be able to solve both a historical and an astronomical mystery,” Zijlstra said.

The team of astronomers who made the discovery hail from Hong Kong, the U.K., Spain, Hungary and France.

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