Historical accounts from early explorers detailed crocodiles as a common sight in the Seychelles. However, after permanent settlers arrived in 1770, the crocodile population rapidly declined and was completely exterminated within about 50 years. Researchers from Germany and the Seychelles investigated the evolutionary history of these lost reptiles by comparing DNA from modern saltwater crocodiles with genetic material from historical museum specimens, including rare samples from the extinct Seychelles population.

The genetic findings confirmed a previous theory based on the crocodiles' physical appearance, showing that the Seychelles animals were closely related to saltwater crocodiles living thousands of kilometers away. This supports the idea that crocodiles are capable of crossing vast distances.

Saltwater crocodiles are uniquely adapted to life at sea, possessing specialized salt glands that allow them to survive extended periods in saltwater. This ability has facilitated their spread across extensive coastlines and remote islands. Experts suggest that the founding population in the Seychelles likely drifted at least 3,000 kilometers across the Indian Ocean from other populations, possibly traveling with ocean currents over generations.

"The founders of the Seychelles population must have drifted at least 3,000 kilometers across the Indian Ocean to reach the remote archipelago, perhaps even much further," stated reptile expert Frank Glaw of the Bavarian State Collections of Natural History, a senior author of the study. The genetic patterns indicate that saltwater crocodile populations have historically remained connected over long distances, highlighting the species' remarkable mobility.

Before the Seychelles population was lost, the saltwater crocodile boasted an even wider range, stretching over 12,000 kilometers from Vanuatu in the Pacific Ocean to the Seychelles in the Indian Ocean, making it one of the most widely distributed reptiles on Earth.

"Whether you're a die-hard space nerd or someone who just really, really enjoys seeing Earth glow from 250 miles up, the countdown has officially begun," Netflix said in a blog post announcing the new NASA+ feed.

Programming will include "jaw-dropping Earth views from the International Space Station (ISS), astronaut spacewalks that make your palms sweat" and rocket launch livestreams, according to Netflix.

NASA said its partnership with the entertainment company, which reported over 300 million subscribers in December, aims to "bring space a little closer to home."

"Our Space Act of 1958 calls on us to share our story of space exploration with the broadest possible audience," wrote Rebecca Sirmons, general manager of NASA+.

The stream is committed to "inspiring new generations -- right from the comfort of their couch or in the palm of their hand from their phone," she added.

NASA+ programming will remain free of charge for viewers on the NASA.gov website and the agency's mobile app.

Netflix announced a similar partnership with French television group TF1 earlier this month, its first such deal with a major traditional broadcaster anywhere in the world.

That programming is slated to launch in summer 2026, giving Netflix subscribers in France access to five TV channels and a streaming platform.

The terms of the Netflix deal were not made public, but follow in the footsteps of other partnerships to expand its content offerings.

The company entered new territory at the end of 2024 by livestreaming two NFL games and a boxing match between YouTube personality Jake Paul and retired professional boxer Mike Tyson.

Tim Bayne, Professor of Philosophy, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The new Tiangong team will carry out experiments with an eye to the space programme's ambitious goal of placing astronauts on the Moon by 2030 and eventually constructing a lunar base.

The Shenzhou-19 mission took off with its trio of space explorers from the Jiuquan Satellite Launch Center in northwest China, state news agency Xinhua and state broadcaster CCTV reported.

Among the crew is Wang Haoze, 34, who is China's only female spaceflight engineer, according to the China Manned Space Agency (CMSA). She is the third Chinese woman to take part in a crewed mission.

"Like everyone else, I dream of going to the space station to have a look," Wang told a media gathering Tuesday alongside her fellow crew members, lined up behind podiums and tall panes of glass to seal them off from the public.

"I want to meticulously complete each task and protect our home in space," she said.

"I also want to travel in deep space and wave at the stars."

Headed by Cai Xuzhe, the team will return to Earth in late April or early May next year, CMSA Deputy Director Lin Xiqiang said at a separate press event confirming the launch.

Cai, a 48-year-old former air force pilot, brings experience from a previous stint aboard Tiangong as part of the Shenzhou-14 mission in 2022.

"Having been selected for the new crew, taking on a new role, facing new tasks and new challenges, I feel the honour of my mission with a great responsibility," said Cai.

The aerospace veteran added that the crew was now "fully prepared mentally, technically, physically and psychologically" for the mission ahead.

Completing the astronaut lineup is 34-year-old man Song Lingdong.

The crew currently aboard the Tiangong space station is scheduled to return to Earth on November 4 after completing handover procedures with the incoming astronauts, Lin said.

- 'Space dream' -

China has ramped up plans to achieve its "space dream" under President Xi Jinping.

Its space programme was the third to put humans in orbit and has also landed robotic rovers on Mars and the Moon.

Crewed by teams of three astronauts that are rotated every six months, the Tiangong space station is the programme's crown jewel.

Beijing says it is on track to send a crewed mission to the Moon by 2030, where it intends to construct a base on the lunar surface.

The Shenzhou-19 crew's time aboard Tiangong will see them carry out various experiments, including some involving "bricks" made from components imitating lunar soil, CCTV reported.

These items -- to be delivered to Tiangong by the Tianzhou-8 cargo ship in November -- will be tested to see how they fare in extreme radiation, gravity, temperature and other conditions.

Due to the high cost of transporting materials into space, Chinese scientists hope to be able to use lunar soil for the construction of the future base, CCTV reported.

The Shenzhou-19 mission is primarily about "accumulating additional experience", Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics in the United States, told AFP.

While this particular swap of astronaut crews and upcoming six-month stint aboard Tiangong may not witness major breakthroughs or feats, it is still "very valuable to do", said McDowell.

China has in recent decades injected billions of dollars into developing an advanced space programme on par with the United States and Europe.

In 2019, China successfully landed its Chang'e-4 probe on the far side of the moon -- the first spacecraft ever to do so. In 2021, it landed a small robot on Mars.

Tiangong, whose core module launched in 2021, is planned to be used for about 10 years.

The study was published in The Astrophysical Journal.

The findings have been published in Nature Astronomy.

How old? She probably died in her mid-40s, indicated again by her teeth which are worn down almost to the roots.

"By the time the teeth are getting this worn, chewing is not as effective as it would have been - so she's not able to eat in quite the same way," explained Dr Pomeroy.

"We've got some other indications of poor dental health - some infections, some gum disease as well. By this time, I think she was getting to the natural end of life."

For a long time, scientists considered Neanderthals brutish and unsophisticated by comparison with our species.

But that view has been transformed since the discoveries at Shanidar.

The cave is famous for displaying what appears to be some kind of burial practice. Bodies were carefully placed in a gully next to a tall rock pillar. All the dead shared a similar orientation in how they were laid out.

Pollen throughout one skeleton led some to argue these Neanderthals might have been interred with flowers, suggestive perhaps of a spiritual awakening, even religion.

But the British team thinks it more likely the pollen was left by later burrowing bees, or perhaps from flowering branches that were placed on top of the bodies.

"Not because of the flowers on the branches but because the branches themselves could have prevented the likes of hyenas getting at the bodies," said Prof Chris Hunt of Liverpool John Moores University.

"I would hesitate to use the word 'burial'; I think I would use the word 'placement' to get away from the idea of a vicar and the church. But there's absolutely no doubt that they maintained a tradition of this is where you put grandma."

The new observations show the top of the "horse's mane," revealing for the first time the small scale structures on the edge of the giant cloud of dust and gas.

Located roughly 1,300 light years away in the constellation Orion ("The Hunter"), the iconic silhouette of a horse's head and neck rises from what look like churning waves of interstellar foam.

Webb, the most powerful space observatory ever built, is able to detect infrared light at unprecedented resolutions, revealing objects that cannot be seen using the visible spectrum in optical telescopes.

"An international team of astronomers has revealed for the first time the small-scale structures of the illuminated edge of the Horsehead," a NASA statement said.

As ultraviolet light evaporates the dust cloud, particles are swept away by the outflow of heated gas -- a process Webb has now shown in action.

The observations have also given astronomers new insights into how dust blocks and emits light, and a better idea of the nebula's multidimensional shape.

The work was the result of an study led by Karl Misselt of the University of Arizona, and published Monday in Astronomy & Astrophysics.

The Horsehead Nebula has fascinated space enthusiasts since its discovery in 1888 by the renowned Scottish astronomer Williamina Fleming.

While it appears shadowy in optical light, the nebula comes to life when viewed through infrared wavelengths, taking on transparent and ethereal hues.

This delicate pillar of hydrogen gas infused with dust is being steadily worn away by the radiation of a nearby star. Astronomers estimate the Horsehead will disappear in another five million years.

Odysseus, built by Houston-based Intuitive Machines, touched down near the lunar south pole Thursday at 2323 GMT, after a nail-biting final descent where flight controllers had to switch to an experimental landing system and took several minutes to establish radio contact with the lander after it came to rest.

"Today for the first time in more than a half century, the US has returned to the Moon," NASA administrator Bill Nelson said in a video. "Today for the first time in the history of humanity, a commercial company, an American company, launched and led the voyage up there."

Images from an external "EagleCam" designed to shoot out from the spacecraft during its final seconds of descent could be released early Friday, a member of the team that built it told AFP.

"After troubleshooting communications, flight controllers have confirmed Odysseus is upright and starting to send data," Intuitive Machines said in its latest update on X.

"Right now, we are working to downlink the first images from the lunar surface."

A previous moonshot by another American company last month ended in failure, raising the stakes to demonstrate that private industry had what it took to repeat a feat last achieved by US space agency NASA during its manned Apollo 17 mission in 1972.

- Lunar south pole -

Underscoring the technical challenges, an onboard navigation system failed and Odysseus instead flew the final leg of its trip using an experimental laser guidance system developed by NASA to run only as a technology demonstration.

Confirmation of landing was supposed to come seconds after the milestone, but instead nearly 15 minutes passed as announcers mused whether the craft had come down "off angle."

Finally, the company's chief technology officer Tim Crain confirmed "our equipment is on the surface of the Moon and we are transmitting," as applause broke out in mission control.

Odysseus touched down in Malapert A, an impact crater 300 kilometers (180 miles) from the lunar south pole.

NASA hopes to eventually build a long-term presence and harvest polar ice for both drinking water and rocket fuel for an onward journey to Mars under Artemis, its flagship program.

The current mission is "one of the first forays into the south pole to actually look at the environmental conditions to a place we're going to be sending our astronauts in the future," said senior NASA official Joel Kearns.

NASA's first crewed mission to the region is scheduled for no sooner than 2026. America's geopolitical rival China is also planning to send its first crew to the Moon in 2030, ushering in a new era of space competition.

- Exclusive club -

Hexagon-shaped Odysseus, which is about the size of a large golf cart, launched from Florida on February 15 on a SpaceX Falcon 9 rocket, boasting a new liquid methane, liquid oxygen propulsion system that traversed the quarter million mile voyage in quick time.

It carries six NASA science instruments, including cameras to investigate how the lunar surface changes as a result of the engine plume from a spaceship, and a device to analyze clouds of charged dust particles that hang over the surface at twilight as a result of solar radiation.

The rest of the cargo was shipped on behalf of Intuitive Machines' private clients, and includes 125 stainless steel mini Moons by the artist Jeff Koons.

The cargo can run for up to seven days before lunar night occurs, rendering Odysseus inoperable.

NASA paid Intuitive Machines $118 million to ship its hardware under a new initiative called Commercial Lunar Payload Services (CLPS), which it created to delegate cargo services to the private sector to achieve savings and stimulate a wider lunar economy.

The first CLPS mission, by Pittsburgh-based Astrobotic, launched in January, but its Peregrine spacecraft sprung a fuel leak and was eventually brought back to burn up in Earth's atmosphere.

Spaceships landing on the Moon must navigate treacherous terrain and rely on thrusters to control their descent in the absence of an atmosphere.

Until now, only the space agencies of the Soviet Union, United States, China, India and Japan had accomplished the feat, making for an exclusive club.

Fixed to the top of United Launch Alliance's brand new Vulcan rocket, which was making its first flight, Astrobotic's Peregrine Lunar Lander blasted off overnight from Florida's Cape Canaveral Space Force Station, then successfully separated from its launch vehicle.

A few hours later, Astrobotic began reporting technical malfunctions, starting with an inability to orient Peregrine's top-mounted solar panel towards the Sun and keep its onboard battery topped up, owing to a malfunction in its propulsion system.

Though engineers found a way to tilt the spacecraft in the right direction thanks to an "improvised maneuver," the company then posted on X that the same propulsion failure appeared to be the cause of a "critical loss of propellant."

"We are currently assessing what alternative mission profiles may be feasible at this time," Astrobotic said, an apparent admission that the Peregrine would not achieve a controlled touchdown on the Moon as planned.

Peregrine was supposed to reach the Moon, then maintain an orbit for several weeks before landing in a mid-latitude region called Sinus Viscositatis, or Bay of Stickiness, on February 23.

A soft landing on Earth's nearest celestial neighbor has thus far only been accomplished by a handful of national space agencies: the Soviet Union was first, in 1966, followed by the United States, which is still the only country to put people on the Moon.

China has successfully landed three times over the past decade, while India was the most recent to achieve the feat, on its second attempt, last year.

- Pivot to private  -

Now, the United States is turning to the commercial sector to stimulate a broader lunar economy and ship its own science instruments at a fraction of the cost, under the Commercial Lunar Payload Services (CLPS) program -- but Astrobotic's apparent failure could lead to criticism of the new strategy.

NASA Administrator Bill Nelson however doubled down, praising the success of ULA's Vulcan rocket on its maiden flight, which maintained the company's 100 percent success rate in more than 150 launches.

"Spaceflight is a daring adventure, and @astrobotic is making progress for CLPS deliveries and Artemis. @NASA will continue to expand our reach in the cosmos with our commercial partners," Nelson said on X.

NASA paid Astrobotic more than $100 million, while another contracted company, Houston-based Intuitive Machines, is looking to launch in February and land near the Moon's south pole.

The space agency hopes to use such missions to probe the lunar environment, paving the way for its Artemis program to return astronauts to the Moon later this decade, in preparation for future missions to Mars.

- Failure happens -

Controlled touchdown on the Moon is a challenging undertaking, with roughly half of all attempts failing.

In the absence of an atmosphere that would allow the use of parachutes, a spacecraft must navigate treacherous terrain using only its thrusters to slow descent.

Private missions by Israel and Japan, as well as a recent attempt by the Russian space agency, have all ended in failure -- though Japan's space agency is targeting mid-January for the touchdown of its SLIM lander launched last September.

In addition to the science instruments it carried for NASA, Peregrine contains more colorful cargo paid for by private customers, including a physical Bitcoin and cremated remains and DNA, including those of Star Trek creator Gene Roddenberry, legendary sci-fi author and scientist Arthur C. Clarke, and a dog.

The Navajo Nation, America's largest Indigenous tribe, has objected to sending human remains to the Moon, calling it a desecration of a sacred space. Though they were granted a last-ditch meeting with White House and NASA officials, their objections failed to remove the cargo.

The research has been published in Nature.

This much we know.

But exactly how the impact of the asteroid Chicxulub caused all those animals to go extinct has remained a matter of debate.

The leading theory recently has been that sulphur from the asteroid's impact -- or soot from global wildfires it sparked -- blocked out the sky and plunged the world into a long, dark winter, killing all but the lucky few.

However research published Monday based on particles found at a key fossil site reasserted an earlier hypothesis: that the impact winter was caused by dust kicked up by the asteroid.

Fine silicate dust from pulverised rock would have stayed in the atmosphere for 15 years, dropping global temperatures by up to 15 degrees Celsius, researchers said in a study in the journal Nature Geoscience.

Back in 1980, father-and-son scientists Luis and Walter Alvarez first proposed that the dinosaurs were killed off by an asteroid strike that shrouded the world in dust.

Their claim was initially met with some scepticism -- until a decade later when the massive crater of Chicxulub was found in what is now the Yucatan Peninsula on the Gulf of Mexico.

Now, scientists largely agree that Chicxulub was to blame.

But the idea that it was sulphur, rather than dust, that caused the impact winter has become "very popular" in recent years, Ozgur Karatekin, a researcher at the Royal Observatory of Belgium, told AFP.

Study co-author Karatekin said this was because the dust from the impact was thought to be the wrong size to stay in the atmosphere for long enough.

For the study, the international team of researchers was able to measure dust particles thought to be from right after the asteroid struck.

- 'Catastrophic collapse' -

The particles were found at the Tanis fossil site in the US state of North Dakota.

Though 3,000 kilometres (1,865 miles) away from the crater, the site has preserved a number of remarkable finds believed to be dated from directly after the asteroid impact in sediment layers of an ancient lake.

The dust particles were around 0.8 to 8.0 micrometres -- just the right size to stick around in the atmosphere for up to 15 years, the researchers said.

Entering this data into climate models similar to those used for current-day Earth, the researchers determined that dust likely played a far greater role in the mass extinction than had previously been thought.

Out of all the material that was shot into the atmosphere by the asteroid, they estimated that it was 75 percent dust, 24 percent sulphur and one percent soot.

The dust particles "totally shut down photosynthesis" in plants for at least a year, causing a "catastrophic collapse" of life, Karatekin said.

Sean Gulick, a geophysicist at the University of Texas at Austin and not involved in the research, told AFP that the study was another interesting effort to answer the "hot question" -- what drove the impact winter -- but did not provide the definitive answer.

He emphasised that discovering what happened during the world's last mass extinction event was important not just for understanding the past, but also the future.

"Maybe we can better predict our own mass extinction that we're probably in the middle of," Gulick said.

The discovery follows a seven-year-round-trip to the distant rock as part of the OSIRIS-REx mission, which dropped off its precious payload in the Utah desert last month for painstaking scientific analysis.

"This is the biggest carbon-rich asteroid sample ever returned to Earth," NASA administrator Bill Nelson said at a press event at the Johnson Space Center in Houston, where the first images of black dust and pebbles were revealed.

Carbon accounted for almost five percent of the sample's total weight, and was present in both organic and mineral form, while the water was locked inside the crystal structure of clay minerals, he said.

Scientists believe the reason Earth has oceans, lakes and rivers is because it was hit with water-carrying asteroids 4 to 4.5 billion years ago, making it a habitable planet.

All life on Earth meanwhile is based on carbon, which forms bonds with other elements to produce proteins and enzymes as well as the building blocks of genetic code, DNA and RNA.

The findings were made through a preliminary analysis involving scanning electron microscopy, X-ray computed tomography and more.

"This stuff is an astrobiologist's dream," said scientist Daniel Glavin, adding there was much more work to be done and the sample would be shared with labs around the world for further study.

- Biggest asteroid sample -

OSIRIS-REx wasn't the first probe to rendezvous with an asteroid and bring back samples for study -- Japan succeeded in the feat twice, returning celestial dust in 2010 and 2020.

But the amount collected -- an estimated 250 grams (half a pound) -- dwarfs that returned by the Japanese missions, with Hayabusa2 managing only 5.4 grams.

Named after an ancient Egyptian deity, Bennu is a "primordial artifact preserved in the vacuum of space," according to NASA, making it an attractive target for study.

Its orbit, which intersects that of our planet, also made the journey easier than going to the Asteroid Belt, which lies between Mars and Jupiter.

In addition to scientific insights, better understanding of Bennu's composition could prove useful if humanity ever needs to steer it away.

While there is no risk of it hitting Earth through the mid 2100s, the chances rise to around 1 in 1,750 between then and the year 2300, NASA says.

Data gathered by the OSIRIS-REx spacecraft revealed the particles making up Bennu's exterior were so loosely packed that if a person were to step onto the surface, they might sink in, much like a pit of plastic balls in children's play areas.

- Future study -

Researchers have so far focused their efforts not on the main sample itself but on "bonus particles," that lay on top of the sample collecting mechanism.

An inspection of the remainder of the sample will follow later.

Back in October 2020, when the OSIRIS-REx probe shot nitrogen gas at Bennu to collect material, a flap meant to seal the sample got wedged open, allowing some of the material to flow out into another compartment.

"The very best 'problem' to have is that there is so much material, it's taking longer than we expected to collect it," said deputy OSIRIS-REx curation lead Christopher Snead, in a statement.

NASA says it will preserve at least 70 percent of the sample at Houston for future study -- a practice first started in the Apollo era with Moon rocks.

"The samples are then available for new questions, new techniques, new instrumentation far into the future," said Eileen Stansbery, division chief of astromaterials research at the Johnson Space Center.

Additional pieces will be sent for public display at the Smithsonian Institution, Space Center Houston, and the University of Arizona.