Stardust: Oldest material on earth found inside meteorite - Al Jazeera English - Canada News Media
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Stardust: Oldest material on earth found inside meteorite – Al Jazeera English



A meteorite that crashed into rural southeastern Australia in a fireball in 1969 contained the oldest material ever found on Earth, stardust that predated the formation of our solar system by billions of years, scientists said on Monday.

The oldest of 40 tiny dust grains trapped inside the meteorite fragments retrieved around the town of Murchison in Victoria state dated from about seven billion years ago, about 2.5 billion years before the sun, Earth and rest of our solar system formed, the researchers said.

In fact, all of the dust specks analysed in the research came from before the solar system’s formation –  known as “pre-solar grains” – with 60 percent of them between 4.6 and 4.9 billion years old and the oldest 10 percent dating to more than 5.6 billion years ago.

Philipp Heck, curator of meteorites at Chicago’s Field Museum which has a piece of the meteorite in its collection, examined the pre-solar grains.

“They’re solid samples of stars, real stardust,” Heck, who led the research published in the scientific journal Proceedings of the National Academy of Sciences, said in a statement.

When the first stars died after two billion years of life they left behind the stardust, which formed into the block which fell to earth as the meteorite in Australia.

The findings were “extremely exciting,” he added.

How stars formed

Although researchers first identified the grains in 1987 their age could not be determined.

But Heck and other colleagues recently used a new method to date these grains, which are microscopic in size.

They are from silicon carbide, the first mineral formed when a star cools.

The findings provide clues on how stars are formed and develop [File: Gilles Chapdelaine/ESA/NASA and Hubble handout via EPA]

To separate the ancient grains from the relatively younger ones, scientists crushed fragments of the meteorite into a powder. Then they dissolved it in acid, which left only the pre-solar particles.

“It’s like burning down the haystack to find the needle,” says Heck.

When dust is in space it is exposed to cosmic rays which slowly change its composition. This allows researchers to date it.

Ten years ago, only 20 grains from the meteorite were dated by a different method. Now, researchers have been able to determine the age of 40 grains, most of which are between 4.6 billion and 4.9 billion years old.

These ages correspond to the moment when the first stars began to break up, and since that type of star lived for two to 2.5 billion years, the stardust can be as old as seven billion years.

“These are the oldest solid materials ever found, and they tell us about how stars formed in our galaxy,” Heck said.

The new dating by this team confirms an astronomical theory which predicted a baby boom of stars before the formation of our sun, instead of a constant rhythm of star formation.

“We basically came to the conclusion that there must have been a time in our galaxy when more stars formed than normal, and at the end of their lives they become dust producing,” Heck told AFP news agency.

Scientists previously had found a pre-solar grain in the Murchison meteorite that was about 5.5 billion years old, until now the oldest-known solid material on Earth.

The oldest-known minerals that formed on Earth are found in rock from Australia’s Jack Hills that formed 4.4 billion years ago, 100 million years after the planet itself.

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NASA Exploring Future Moon and Mars Homes Made of Fungi – Interesting Engineering



What do you imagine life on the Moon and Mars might be like? Do you imagine futuristic buildings made of metal? Well, NASA imagines some a lot more sustainable options.


The agency is working on buildings made of fungi. Yes, you read that correctly… Fungi!

Called the myco-architecture project and run by NASA’s Ames Research Center in California’s Silicon Valley, this new initiative is seeking to “grow” habitats on the Moon, Mars, and even potentially Earth.

Like a turtle

“Right now, traditional habitat designs for Mars are like a turtle — carrying our homes with us on our backs – a reliable plan, but with huge energy costs,” said in a statement Lynn Rothschild, the principal investigator on the project. “Instead, we can harness mycelia to grow these habitats ourselves when we get there.”

What they envision is straight out of a science fiction film. Space explorers would carry with them compact habitat built out of lightweight material with dormant fungi. 

Once in their final destination, the explorers would simply add water and the fungi would grow across that framework creating a living habitat. Of course, we are a long way off from this happening.

Still, early-stage research is seeking to prove that such structures could be viable options. How would these structures look like?

Three-layered domes

NASA describes them as three-layered domes: 

“The outer-most layer is made up of frozen water ice, perhaps tapped from the resources on the Moon or Mars. That water serves as a protection from radiation and trickles down to the second layer – the cyanobacteria. This layer can take that water and photosynthesize using the outside light that shines through the icy layer to produce oxygen for astronauts and nutrients for the final layer of mycelia.

That last layer of mycelia is what organically grows into a sturdy home, first activated to grow in a contained environment and then baked to kill the life-forms – providing structural integrity and ensuring no life contaminates Mars and any microbial life that’s already there.”

NASA also believes that their project has applications right here on Earth. It could provide a more eco-friendly and sustainable method of living.

What do you think? Would you be interested in living in a fungi home?

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How SpaceX's Crew Dragon launch abort test today works in 10 not-so-easy steps –



NOTE: This story has been updated to reflect SpaceX’s new launch time.

SpaceX will fly a major test flight of its Crew Dragon space taxi today (Jan. 19) to prove the spacecraft’s launch escape system can carry astronauts to safety in the event of a rocket emergency. The launch, set for 10:30 a.m. EST (1530 GMT) is unlike anything SpaceX has done before. 

Called an in-flight abort, the SpaceX test will demonstrate Crew Dragon’s SuperDraco launch abort system designed to rip the spacecraft free of its Falcon 9 rocket in the event of a launch failure. It’s the last major test for Crew Dragon before SpaceX can start flying astronauts for NASA under a Commercial Crew Program contract. 

You can watch the launch live here and on the homepage, courtesy of SpaceX, beginning at about 10:10 a.m. EST (1510 GMT). You can also watch the launch directly from SpaceX here, or from NASA here.

Scroll down for a look at how the major SpaceX test flight will work in 10 steps.

1. Launch

(Image credit: SpaceX)

Like every SpaceX mission, Crew Dragon’s in-flight abort test begins with a Falcon 9 launch. 

Liftoff is set for no earlier than 10:30 a.m. EST (1530 GMT) from the historic Launch Pad 39A of NASA’s Kennedy Space Center. In the hours leading to launch, SpaceX and NASA will practice everything needed for an actual crew launch.

SpaceX has a 6-hour window in which to launch Crew Dragon and wants optimal weather conditions for the launch itself, as well as for the spacecraft’s offshore recovery in the Atlantic Ocean. Visibility is a key concern for the launch. 

SpaceX has already delayed the launch 24 hours (from Saturday, Jan. 18) due to bad weather. Another launch opportunity is on Monday, Jan. 20, but weather forecasts are less favorable. 

2. A proven rocket

(Image credit: SpaceX)

SpaceX is using a proven rocket for the Crew Dragon in-flight abort test. 

The Falcon 9 first-stage booster on this flight is making its fourth flight and is actually the first Block 5 version of the rocket SpaceX ever launched. The booster launched a satellite for Bangladesh in May 2018, an Indonesian satellite in August of that same year and then finally a set of 64 satellites in a rideshare mission in December 2018.

SpaceX will not recover this veteran booster. It should break apart, or maybe even explode, after Crew Dragon separates from the rocket’s second stage. The first and second stages are fully fueled, but the second stage carries a mass simulator in place of an engine since one is not needed for this flight. 

3. SuperDraco abort engines fire

(Image credit: SpaceX)

Precisely 84 seconds after liftoff, as the Falcon 9 rocket is flying Mach 2.3, Crew Dragon will fire its eight SuperDraco engines and rip itself free of the rocket’s second stage. 

SpaceX is triggering the abort test while Crew Dragon and its Falcon 9 are about 14 miles (19 kilometers) high and 2.5 miles (4 km) down range. 

“Dragon will leave the Falcon very quickly,” Benji Reed, SpaceX’s director of crew mission management, said during a news conference Friday (Jan. 17).

The open maw of Falcon 9’s second stage, still attached to the first stage booster, should act as an air scoop, slowing the booster and ultimately leading it to break apart. The booster could explode and be visible from the ground, Reed said. 

“There will probably be some ignition,” Reed said. “We’ll see something.”

4. Abort system shutdown

(Image credit: SpaceX)

Crew Dragon’s SuperDracos will fire for 10 seconds, pulling the capsule free of the Falcon 9 and carrying upward on a suborbital trajectory.

The eight SuperDraco on Crew Dragon are arranged in four pairs of two around the capsule’s side walls, with each capable of generating 16,000 lbs. of thrust. They are more advanced and more powerful than Dragon’s Draco attitude thrusters. SpaceX makes them through direct metal laser sintering, essentially 3D printing. 

5. Crew Dragon trunk jettison

(Image credit: SpaceX)

About 2.5 minutes after liftoff, Crew Dragon will jettison its “trunk” service module. The cylindrical, finned module contains the solar arrays and other gear required to sustain Crew Dragon’s taxi flights to the International Space Station for NASA. 

During reentry, Crew Dragon jettisons its trunk just like SpaceX’s Cargo Dragon vehicles. This clears the spacecraft’s heat shield for entry and prepares the spacecraft for a splashdown landing in the ocean. 

6. Prepare for entry

(Image credit: SpaceX)

Just after the 3-minute mark, Crew Dragon will fire its regular Draco thrusters to orient the space capsule for entry and splashdown. 

Crew Dragon will not reach space on this launch. The highest the capsule should fly is about 24.8 miles (40 km), according to Reed. 

7. Drogue chutes deploy

(Image credit: SpaceX)

About 5.5 minutes after liftoff, Crew Dragon will begin releasing parachutes to slow itself for splashdown. 

The first still will be the release of two drogue chutes to stabilize the capsule and prepare it for the release of its four main parachutes. 

8. Main parachutes deploy

(Image credit: SpaceX)

Shortly after the drogue chutes deploy, Crew Dragon will release its four main parachutes to slow the spacecraft’s descent ahead of splashdown. 

The parachutes on this Crew Dragon are SpaceX’s newest version, the Mark 3 parachute design. SpaceX has been testing parachutes to make sure they will safely return a Crew Dragon to Earth. To date, the company has flown 80 tests, including 10 successful tests of the four-parachute arrangement. 

This flight will mark a major practical test of the parachute design, which has passed a series of drop tests in recent months, but not yet been used in an actual flight. 

9. Splashdown

A step-by-step look at SpaceX's major Crew Dragon in-flight abort launch test to demonstrate the spacecraft's emergency escape system in January 2020.

(Image credit: SpaceX)

About 10 minutes after launch, Crew Dragon will splashdown in the Atlantic Ocean. According to Reed, the drop zone is between 18 and 21 miles offshore (30-35 km). 

SpaceX’s recovery ship, the GO Searcher, will be looking for Crew Dragon ahead of its splashdown, setting the stage for the final step of the mission: Recovery.

10. Crew Dragon recovery

(Image credit: SpaceX)

Crew Dragon’s in-flight abort test will give SpaceX a unique chance to test its recovery procedures for astronauts returning from space. 

The company has staged its recovery ship, the GO Searcher, near the splashdown zone and expects its retrieval team to reach the capsule shortly after it lands. 

“When Dragon splashes down, we’ll be approaching the vehicle within minutes,” Reed said. 

In addition to its regular recovery team, SpaceX has enlisted the aid of the Air Force Detachment-3, an emergency team of divers and officials on call to aid astronaut recovery in the event of an emergency. 

After Crew Dragon is safely on board GO Searcher, the ship will return to Cape Canaveral so it can be studied to see how it fared during the test. 

SpaceX hopes to begin flying astronauts to the International Space Station for NASA later this year. The first crewed flight, carrying NASA astronauts Bob Behknen and Doug Hurley on the Demo-2 flight, could launch as early as March if the abort system test goes well, according to Spaceflight Now.

SpaceX is one of two companies with multi-billion-dollar contracts to fly astronauts for NASA. The other company, Boeing, will fly astronauts on its Starliner spacecraft, which launches on a crew-rated Atlas V rocket. Boeing also plans to begin crewed flights this year.

Follow us on Twitter @Spacedotcom or on Facebook.

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Dinosaurs grew feathers differently from birds, fossil of a 'dancing dragon' shows – The Japan Times



An exquisite fossil of a fierce little Chinese dinosaur dubbed the “dancing dragon” that lived 120 million years ago — an older cousin of the Velociraptor — is showing scientists that feathers grew differently on dinosaurs than on birds.

The two-legged Cretaceous Period dinosaur, called Wulong bohaiensis, was a bantamweight meat-eater — a bit bigger than a crow — residing in a lakeside environment, researchers said. It possessed a scaly face, a mouth full of pointy teeth and one particularly dangerous toe claw, and probably hunted small mammals, lizards, birds and fish.

Wulong’s fossil, unearthed in Liaoning Province in northeastern China, includes a complete skeleton as well as soft tissues like feathers rarely preserved in such detail. Its long arms and legs each had sets of feathers that looked similar to those on bird wings, while most of the rest of its body was covered by fluffy filaments.

At the end of its long, bony tail — fused into a stiff rod — were two very long feathers.

“The specimen of Wulong is a gorgeous fossil. With the feathers and claws, I think it would have been beautiful and just a little bit scary. I’d love to see one alive,” said San Diego Natural History Museum paleontologist Ashley Poust, who led the research, published in the Anatomical Record journal.

“I don’t think we know yet how it used its feathers,” Poust said. “It seems likely that they helped with temperature regulation and signaling to other animals, but what this would have looked like and how much these functions mattered remains unclear.”

Birds evolved from small feathered dinosaurs roughly 150 million years ago. But there were many feathered dinosaurs that did not fly, like Wulong. Scientists are eager to understand the plumage differences between birds and these feathered dinosaurs.

A close examination of bones showed this Wulong individual was about a year old, a juvenile still growing.

“Living birds shoot up to adult size very quickly, mainly as a way of getting strong enough to fly as soon as they can. But they may delay getting their adult feathers for a long time. Gulls, for example, don’t look like adults for three or four years even though they learn to fly in only three months,” Poust said.

The young Wulong appeared to have an adult’s plumage.

“Here is an animal that has all kinds of signals of being a juvenile, outside its bones, inside its bones, in its joints,” Poust said. “And it has long, isolated plumes extending from its already-very-long tail. This is quite different from living birds and tells us that these decorative feathers preceded adulthood in dinosaurs. Of course, perhaps they’re using these feathers in a very different way from living birds, too.”

Wulong means “dancing dragon,” so named because of its fossilized skeleton’s active-looking pose. It belongs to a group of meat-eaters called dromaeosaurs, which also includes Velociraptor. That dinosaur lived 75 million years ago in Mongolia and appears in the “Jurassic Park” films.

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