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A giant sloth graveyard shows how these enormous animals died — and lived –



An enormous pile of enormous bones excavated in Ecuador has given new insight into the behaviour of extinct giant ground sloths.  

Giant ground sloths lived in North and South America for millions of years until their extinction around the end of the last ice age — about 11,000 years ago. The largest species of giant ground sloths rivalled African elephants in size, and this new research suggests that their behaviour might have been very elephant-like as well.

“Between 10,000 and 50,000 years ago, depending on which continent you’re on, basically all ice-free continents had ecosystems that looked a lot more like a modern African ecosystem,” said researcher Emily Lindsey in an interview with Bob McDonald on Quirks & Quarks

“There were a lot of very large animals in that ecosystem and these sloths … were some of the largest.”

Seeping tar was the key to fossil preservation

Giant ground sloth remains have been found in many locations in the Americas, but the find at a site called Tanque Loma in Ecuador in the early 2000s was unique. First uncovered by an oil company during exploration, the site was a “tar seep” in which plant and animal remains had been sealed in naturally occurring tar.

The most famous similar site is Lindsey’s research home — she’s assistant curator and excavation site director at the La Brea Tar Pits in Los Angeles. But she said the preservation here is a little different.

Researcher Emily Lindsey at the excavation site in Ecuador surrounded by sloth bones. (Emily Lindsey)

“It’s a site that probably formed not through large animals getting actually trapped in the tar, but from an asphalt seep that arose after a bone bed was deposited, and just fortuitously preserved the bone bed in situ.”

Excavations over a period of nearly two decades revealed that the tar seep had preserved various plant and animal remains. The most notable were hundreds of bones from one of the largest species of giant sloth that ever lived, known scientifically as Eremotherium laurillardi, which survived as a species for about five million years.

Adults of this species weighed upward of three tonnes and could reach a length of up to six metres. They were ground dwelling herbivores who could feed on foliage high in tree tops by rearing up on their powerful hind legs.

Possibly a family group 

The excavated bones turned out to be from at least 22 individual animals, from small, dog-sized infants to full-sized adults. The context in which the bones were found suggested the animals died at roughly the same time, and also revealed the nature of the location.

“We believe that the site was a spring-fed marsh,” said Lindsey. “[It] probably had a lot of vegetation and it was probably an attractive area for large animals to come and spend time in [an] otherwise still somewhat arid tropical environment.”

La Brea Tar Pits staff and Ecuadoran students excavate and collect giant sloth bones at the Tanque Loma tar pit locality in Ecuador. (Emily Lindsey)

This seemed like a benign environment for giant sloths, so finding the remains of so many animals that had died at the same time was a mystery.

Fortunately the tar seep had preserved more evidence than bones. In and around the remains was a large amount of plant material — small branches, stems and twigs, all sharply cut into roughly 2.5-centimetre lengths.

At first Lindsey didn’t know what to make of this material. 

“It wasn’t until later when I was talking with a friend who is a retired professor of geography, and he told me a story that he had been monitoring a hippo wallow in Africa back in the ’70s,” she said.

Her colleague described how a drought had concentrated hippos around the small pond, and as a matter of course, the hippos defecated into it. A large amount of feces concentrated in the water. 

“It created this very unsanitary environment and thus this contributed to this rapid development of this disease that ended up wiping out their population,” she said.

Lindsey then realized that the characteristically shaped plant material she’d found associated with the sloth bones had probably been cut by their teeth, and was either gut contents or feces — a large amount of it.

Hippos congregate in large numbers in pools in Africa, contaminating them with feces. Observations of a die-off at such a pool inspired the idea that a group of ancient ground sloths might have died in a similar way. (Chris Dutton)

Contaminated water might have led to catastrophe

“At least a plausible explanation for how these animals died was something similar to what happened with this hippopotamus population that my co-author had observed in Africa,” Lindsey said.

Animals trapped by drought conditions near the shrinking wallow contaminated it, and this led to the mass death.

That meant they had a likely explanation for how the animals died. But more interesting was what the remains and the site said about how giant sloths lived.

“It’s not implausible to think, based on group situations that we see in other very large animals today, like elephants or other large savanna vertebrates, that there’s some sort of familial connection,” said Lindsey.

“These animals all died at a very similar time and were probably part of one large group. So they probably were social or gregarious animals.”

Written and produced by Jim Lebans

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With SpaceX's first astronaut launch, a new era of human spaceflight has dawned –



We’ve gotten our hopes up before.

The success of NASA’s Apollo moon missions half a century ago, for example, made Mars seem very much within reach for human explorers. Indeed, the space agency drew up plans to put boots on the Red Planet by the early 1980s, but shifting political and societal winds killed that idea in the cradle.

In 1989, President George H.W. Bush announced the Space Exploration Initiative, which aimed to send astronauts back to the moon by the end of the 1990s and get people to Mars in the 2010s. His son, President George W. Bush, also aimed for a crewed lunar return, with a program called Constellation, whose contours were outlined in 2004. Each program was soon axed by the next administration to come into power.

Full coverage: SpaceX’s historic Demo-2 astronaut launch explained

A SpaceX Falcon 9 rocket launch launches two NASA astronauts into orbit on a Crew Dragon spacecraft from Pad 39A of the Kennedy Space Center in Florida on May 30, 2020. (Image credit: SpaceX)

So it’s natural for space fans to greet the grand pronouncements occasioned by SpaceX’s first crewed launch on Saturday (May 30) with a bit of skepticism. Yes, the Demo-2 mission to the International Space Station (ISS), the first orbital human spaceflight to depart from American soil since NASA retired its space shuttle fleet in 2011, is a big deal. But does it really show that “the commercial space industry is the future,” as President Donald Trump said shortly after liftoff?

Actually, it very well might. 

Demo-2 is far from a one-off, after all. It’s a test flight designed to fully validate SpaceX’s Crew Dragon capsule and Falcon 9 rocket for crewed missions to the ISS. The company holds a $2.6 billion NASA contract to conduct six such operational flights, the first of which is targeted for late August, provided Demo-2 goes well.

SpaceX is a highly ambitious company that has already accomplished a great deal in the final frontier; it’s been flying robotic cargo flights to the ISS for NASA since 2012, for example. So, there’s little reason to doubt SpaceX’s ability to fulfill that contract, and to execute a variety of other missions in Earth orbit as well.

Elon Musk’s company has in fact already inked Crew Dragon deals with other customers. For example, Houston-based company Axiom Space, which aims to build a commercial space station in Earth orbit, has booked a Crew Dragon flight to the ISS, with liftoff targeted in late 2021. And the space tourism outfit Space Adventures plans to use the capsule at around the same time, to carry passengers on a mission to high Earth orbit, far above the ISS. 

Then there’s Boeing. Like SpaceX, Boeing signed a contract with NASA’s Commercial Crew Program to fly six crewed missions to and from the ISS. Boeing will fulfill the deal with a capsule called CST-100 Starliner, which has made one uncrewed trip to orbit to date. 

That flight, which launched this past December, didn’t go as planned; Starliner was supposed to meet up with the ISS but suffered a glitch with its onboard timing system and got trapped in the wrong orbit. But Boeing plans to refly the uncrewed ISS mission later this year and put astronauts on Starliner shortly thereafter, provided everything goes well.

Related: Four new US spaceships may start launching people into space soon

Activity is heating up in the suborbital realm as well. 

For example, Richard Branson’s Virgin Galactic has already flown two piloted missions to suborbital space with its newest SpaceShipTwo vehicle, VSS Unity. The company is in the final phases of its test campaign and looks poised to begin carrying space tourists aboard the six-passenger Unity soon.

And Blue Origin, the spaceflight company run by Amazon’s Jeff Bezos, has reached space numerous times with its suborbital vehicle, known as New Shepard. Those test flights have been uncrewed to date, but it probably won’t be long before New Shepard begins carrying customers as well.

The names on this list chip away at the skepticism even more. We aren’t talking about cash-strapped startups here; Bezos is the world’s richest man, and Musk and Branson are both billionaires. And Boeing is an aerospace giant with a long history of achievement in the human spaceflight realm. The company is the prime contractor for the ISS, for example, and it built the first stage of NASA’s huge Saturn V rocket, which launched the Apollo moon missions. 

So there’s real reason to hope that an exciting new era of human spaceflight has dawned — perhaps one that will even see people riding private spaceships to the moon, Mars and other destinations in deep space. 

Musk has long stressed that he founded SpaceX back in 2002 primarily to help humanity colonize the Red Planet, and the company is already building and testing prototypes of Starship, the vehicle designed to make that happen. And Bezos has repeatedly said that his overarching vision for Blue Origin involves helping to get millions of people living and working in space.

This coming private boom isn’t booting NASA off the human-spaceflight block, of course. The space agency has deep space ambitions of its own. Its Artemis program aims to land two astronauts near the moon’s south pole in 2024 and establish a long-term human presence on and around the moon by 2028. 

And the moon will be a stepping stone, if all goes according to NASA’s plan, teaching the agency the skills and techniques required to put boots on Mars.

NASA wants to make that giant leap in the 2030s. We’ll see if the political will and the funding hold long enough for the agency to do it.

Mike Wall is the author of “Out There” (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook

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How to watch SpaceX’s Crew Dragon dock with the International Space Station live – The Verge



On Saturday afternoon, SpaceX launched its first human crew to space for NASA on the company’s new Crew Dragon spacecraft — but the mission isn’t over yet. After spending nearly a full day in orbit, the two passengers on board SpaceX’s vehicle, NASA astronauts Bob Behnken and Doug Hurley, will attempt to dock with the International Space Station this morning.

SpaceX’s Crew Dragon has an automatic docking system, which uses a series of sensors and cameras to help the vehicle approach the ISS and then grab on to an existing docking port. The Crew Dragon successfully tested out this technique last year when SpaceX launched a test version of the vehicle to the ISS without crew on board. But this time, the Crew Dragon will carry very precious cargo.

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While the Crew Dragon is capable of getting Bob Behnken and Doug Hurley to the station on its own, the two astronauts do plan to do some manual flying when they get close to the ISS. Somewhere between 220 and 170 meters out from the station, the crew will practice flying the capsule manually, using the vehicle’s touchscreen interface inside. Once they’re done, the automatic system will take over again, and the Crew Dragon will do the rest of the work to get to the station.

NASA is providing round-the-clock coverage of the Crew Dragon’s mission right now, but things kick off this morning when Behnken and Hurley do a broadcast from inside the Crew Dragon. Docking will come about a few hours later at 10:29AM ET. All of the events will take place live on NASA’s TV stream above.

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Trump Given False Credit For Bush- And Obama-Era Space Program



Today the Space X Dragon “Endeavor” launched. It was the first time since 2011 that the U.S. had launched humans into space. The Commercial Crew Development Program was started during the George W. Bush administration, and was expanded through the NASA Authorization Act of 2010, approved by Congress and signed by President Obama.

JimBridenstine, the Administrator of NASA, was nominated by President Trump in 2017 and the Senate confirmed him in 2018 with a party-line vote, 50-49. All previous NASA administrators have been scientists or engineers — Bridenstine is neither. He is the first politician to head NASA.

Bridenstine gave a speech after the launch where the focus was put on the accomplishments of Trump, and the previous administrations’ roles in this mission were never mentioned. Bridenstine made a point to mention that there were layoffs at NASA in 2010, a pointed jab at the Obama administration. The reason for the layoffs was that the space shuttle missions were wrapping up. As you read above, the NASA Authorization Act of 2010, signed by President Obama, expanded the crew development program. All contracts for today’s mission, including SpaceX’s, were completed during the Obama administration.  Trump and Pence also spoke at the event. described Trump’s address after the launch as something that “sounded like a campaign speech.”

Later, Bridenstine gave an interview where the questions were focused on Trump. Bridenstine offered, “We now have an administration that is fully supportive of our spaceflight initiatives…but also from a Space Force perspective.” Keep in mind, again, that the crew development program was started during the George W. Bush administration, and expanded during the Obama administration.

The U.S. Air Force already had jurisdiction over space, so the creation of the Space Force was redundant. Astronaut Mark Kelly said of Space Force in a tweet, “This is a dumb idea. The Air Force does this already. That is their job. What’s next? We move submarines to the 7th branch and call it the under-the-sea force?”

Bridenstine added during the interview, “[Trump] also said were going to go to the moon by 2024.  That means he’s putting himself at risk to say, ‘look, I’m going to be accountable, potentially, I’m going to be accountable to the initiatives that I put forward,’ and I think that’s, we have not had that kind of leadership for space in a long, long time and I’m so grateful for it.”

A plan to go to the moon, as you can expect, takes years of preparation. Much longer than Trump has been in office. It’s unclear what risk Bridenstine was referring to, as the initiatives for the crew development program were begun during the George W. Bush administration.

This speech and interview were a marked shift from statements Bridenstine made three days prior, a day before the initial planned Dragon launch.  On May 27th, an interview with Elon Musk and Bridenstine had comments from Bridenstine that focused on the contributions of NASA and SpaceX to the Dragon mission and didn’t mention Trump at all.

Three days later, what appeared originally to be a NASA administrator that is a little out of his element but just really likes space turned into an administrator that rarely acknowledged the endless amount of manpower put into the crew development program. Bridenstine appeared to go from space enthusiast to Trump campaign manager.

Some space enthusiasts expressed dismay at Bridenstine’s speech and interview, including the constant focus on Trump. Journalist Henry Brean tweeted, “What better moment is there for the NASA administrator to talk about the big risk the president is taking than when two astronauts are riding a rocket into space?”



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Edited By Harry Miller

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