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Davidbiz
30 Mar 2025 - 08:36 pm
While the Cumberland sample may contain longer chains of fatty acids, SAM is not designed to detect them. But SAM’s ability to spot these larger molecules suggests it could detect similar chemical signatures of past life on Mars if they’re present, Williams said.
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“Curiosity is not a life detection mission,” Freissinet said. “Curiosity is a habitability detection mission to know if all the conditions were right … for life to evolve. Having these results, it’s really at the edge of the capabilities of Curiosity, and it’s even maybe better than what we had expected from this mission.”
Before sending missions to Mars, scientists didn’t think organic molecules would be found on the red planet because of the intensity of radiation Mars has long endured, Glavin said.
Curiosity won’t return to Yellowknife Bay during its mission, but there are still pristine pieces of the Cumberland sample aboard. Next, the team wants to design a new experiment to see what it can detect. If the team can identify similar long-chain molecules, it would mark another step forward that might help researchers determine their origins, Freissinet said.
“That’s the most precious sample we have on board … waiting for us to run the perfect experiment on it,” she said. “It holds secrets, and we need to decipher the secrets.”
Briony Horgan, coinvestigator on the Perseverance rover mission and professor of planetary science at Purdue University in West Lafayette, Indiana, called the detection “a big win for the whole team.” Horgan was not involved the study.
“This detection really confirms our hopes that sediments laid down in ancient watery environments on Mars could preserve a treasure trove of organic molecules that can tell us about everything from prebiotic processes and pathways for the origin of life, to potential biosignatures from ancient organisms,” Horgan said.
Dr. Ben K.D. Pearce, assistant professor in Purdue’s department of Earth, atmospheric, and planetary sciences and leader of the Laboratory for Origins and Astrobiology Research, called the findings “arguably the most exciting organic detection to date on Mars.” Pearce did not participate in the research.
Jasonham
30 Mar 2025 - 07:58 pm
Water and life
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Lightning is a dramatic display of electrical power, but it is also sporadic and unpredictable. Even on a volatile Earth billions of years ago, lightning may have been too infrequent to produce amino acids in quantities sufficient for life — a fact that has cast doubt on such theories in the past, Zare said.
Water spray, however, would have been more common than lightning. A more likely scenario is that mist-generated microlightning constantly zapped amino acids into existence from pools and puddles, where the molecules could accumulate and form more complex molecules, eventually leading to the evolution of life.
“Microdischarges between obviously charged water microdroplets make all the organic molecules observed previously in the Miller-Urey experiment,” Zare said. “We propose that this is a new mechanism for the prebiotic synthesis of molecules that constitute the building blocks of life.”
However, even with the new findings about microlightning, questions remain about life’s origins, he added. While some scientists support the notion of electrically charged beginnings for life’s earliest building blocks, an alternative abiogenesis hypothesis proposes that Earth’s first amino acids were cooked up around hydrothermal vents on the seafloor, produced by a combination of seawater, hydrogen-rich fluids and extreme pressure.
Researchers identified salt minerals in the Bennu samples that were deposited as a result of brine evaporation from the asteroid’s parent body. In particular, they found a number of sodium salts, such as the needles of hydrated sodium carbonate highlighted in purple in this false-colored image – salts that could easily have been compromised if the samples had been exposed to water in Earth’s atmosphere.
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Yet another hypothesis suggests that organic molecules didn’t originate on Earth at all. Rather, they formed in space and were carried here by comets or fragments of asteroids, a process known as panspermia.
“We still don’t know the answer to this question,” Zare said. “But I think we’re closer to understanding something more about what could have happened.”
Though the details of life’s origins on Earth may never be fully explained, “this study provides another avenue for the formation of molecules crucial to the origin of life,” Williams said. “Water is a ubiquitous aspect of our world, giving rise to the moniker ‘Blue Marble’ to describe the Earth from space. Perhaps the falling of water, the most crucial element that sustains us, also played a greater role in the origin of life on Earth than we previously recognized.”
Jessecep
30 Mar 2025 - 07:57 pm
Josh Giddey hits halfcourt buzzer-beater over LeBron James to cap wild finale as the Bulls stun the Lakers
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Josh Giddey hit a game-winning, halfcourt buzzer-beater over LeBron James as the Chicago Bulls stunned the Los Angeles Lakers in one of the wildest endings to an NBA game you are ever likely to see.
Trailing 115-110 with 12.6 seconds remaining, Giddey’s inbound pass found Nikola Vucevic, who pushed the ball to a wide-open Patrick Williams for a corner three-pointer.
James then fluffed the Lakers inbound pass from the baseline, allowing Giddey to steal the ball and find Coby White for a second Bulls triple in quick succession to put Chicago up 116-115 with 6.1 seconds remaining.
Austin Reaves then made a driving layup to put the Lakers ahead 117-116 with 3.3 seconds left, but the game wasn’t done yet.
With no timeouts remaining, Giddey inbounded the ball to Williams from the baseline, got the pass back, took one dribble and launched a shot from beyond halfcourt.
Supporters in the stands seemed frozen in anticipation as the ball sailed through the air, and the United Center then erupted as it fell through the net. After the dramatic win, Giddey found himself being swarmed by his teammates.
“Special moment to do it with these guys, this team,” Giddey said, per ESPN. “We’ve shown over the last month to six weeks that we can beat anybody. The way we play the game, I think it wears people down.
“We get up and down. We run. We put heat on them to get back. A lot of veteran teams don’t particularly want to get back and play in transition.”
Giddey later told the Bulls broadcast that he’d “never made a game-winner before.”
The ending capped an incredible couple of games for the Lakers, who had themselves won their last game against the Indiana Pacers on Wednesday with a buzzer-beating tip-in from James.
Rogerarcam
30 Mar 2025 - 07:42 pm
Siham Haleem, a private tour guide for 15 years, says that Doha now has many world-class, modern museums — the National Museum of Qatar being a firm personal favorite. And yet he says that visiting Sheikh Faisal’s museum should still be on everybody’s to-do list.
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“For those eager to learn about Qatar’s — and the region’s — heritage and beyond, the museum is an ideal destination,” he says. “Personally, I’m captivated by the car collection, the fossils, and especially the Syrian house, painstakingly transported and reassembled piece by piece.”
Stephanie Y. Martinez, a Mexican-American student mobility manager at Texas A&M University in Qatar likes the museum so much she includes it on all of her itineraries for students visiting from the main campus in Texas.
“The guided tours are very detailed, and the collections found at the museum have great variety and so many stories to unfold,” she says. “Truly, the museum has something to pique everyone’s interest. My favorites are the cars and the furniture exhibits showcasing wood and mother-of-pearl details. Definitely one of my favorite museums in Qatar, every time I visit I learn something new.”
Raynor Abreu, from India, also had praise for the unusual and immense collection.
“Each item has its own story, making the visit even more interesting,” he says. “It’s also impressive to know that Sheikh Faisal started collecting these unique pieces when he was very young. Knowing this makes the museum even more special, as it reflects his lifelong passion for history and culture.”
It takes time and dedication to truly examine the many collections within the museum — especially since most of them are simply on display without explanation.
Eclectic it may be, but it’s hard to fault the determination of Sheikh Faisal, who has brought together items that tell the story of Qatar and the Middle East.
Sarah Bayley, from the UK, says she visited the museum recently with her family, including 16 and 19-year-old teenagers, and was won over by its sheer eccentricity.
“Amazing. Loved it. It is a crazy place.”
Chestertiz
30 Mar 2025 - 07:30 pm
Curiosity has maintained pristine pieces of the Cumberland sample in a “doggy bag” so that the team could have the rover revisit it later, even miles away from the site where it was collected. The team developed and tested innovative methods in its lab on Earth before sending messages to the rover to try experiments on the sample.
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In a quest to see whether amino acids, the building blocks of proteins, existed in the sample, the team instructed the rover to heat up the sample twice within SAM’s oven. When it measured the mass of the molecules released during heating, there weren’t any amino acids, but they found something entirely unexpected.
An intriguing detection
The team was surprised to detect small amounts of decane, undecane and dodecane, so it had to conduct a reverse experiment on Earth to determine whether these organic compounds were the remnants of the fatty acids undecanoic acid, dodecanoic acid and tridecanoic acid, respectively.
The scientists mixed undecanoic acid into a clay similar to what exists on Mars and heated it up in a way that mimicked conditions within SAM’s oven. The undecanoic acid released decane, just like what Curiosity detected.
Each fatty acid remnant detected by Curiosity was made with a long chain of 11 to 13 carbon atoms. Previous molecules detected on Mars were smaller, meaning their atomic weight was less than the molecules found in the new study, and simpler.
“It’s notable that non-biological processes typically make shorter fatty acids, with less than 12 carbons,” said study coauthor Dr. Amy Williams, associate professor of geology at the University of Florida and assistant director of the Astraeus Space Institute, in an email. “Larger and more complex molecules are likely what are required for an origin of life, if it ever occurred on Mars.”
Scottroula
30 Mar 2025 - 06:33 pm
Iceberg flotillas
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Located on the west coast, Ilulissat is a pretty halibut- and prawn-fishing port on a dark rock bay where visitors can sit in pubs sipping craft beers chill-filtered by 100,000-year-old glacial ice.
It’s a place to be awed by the UNESCO World Heritage Icefjord where Manhattan skyscraper-sized icebergs disgorge from Greenland’s icecap to float like ghostly ships in the surrounding Disko Bay.
Small boats take visitors out to sail closely among the bay’s magnificent iceberg flotilla. But not too close.
“I was on my boat once and saw one of these icebergs split in two. The pieces fell backwards into the sea and created a giant wave,” said David Karlsen, skipper of the pleasure-boat, Katak. “…I didn’t hang around.”
Disko Bay’s other giants are whales. From June to September breaching humpback whales join the likes of fin and minke whales feasting on plankton. Whale-watching is excellent all around Greenland’s craggy coastline.
Whales are eaten here. Visitors shouldn’t be surprised to encounter the traditional Greenlandic delicacy of mattak — whale-skin and blubber that when tasted is akin to chewing on rubber. Inuit communities have quotas to not only hunt the likes of narwhals but also polar bears, musk-ox and caribou — which can also appear on menus.
Kevinheard
30 Mar 2025 - 06:32 pm
A long time in the making
Curiosity landed in Gale Crater on August 6, 2012. More than 12 years later, the rover has driven over 21 miles (34 kilometers) to ascend Mount Sharp, which is within the crater. The feature’s many layers preserve millions of years of geological history on Mars, showing how it shifted from a wet to a dry environment.
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Perhaps one of the most valuable samples Curiosity has gathered on its mission to understand whether Mars was ever habitable was collected in May 2013.
The rover drilled the Cumberland sample from an area within a crater called Yellowknife Bay, which resembled an ancient lake bed. The rocks from Yellowknife Bay so intrigued Curiosity’s science team that it had the rover drive in the opposite direction to collect samples from the area before heading to Mount Sharp.
Since collecting the Cumberland sample, Curiosity has used SAM to study it in a variety of ways, revealing that Yellowknife Bay was once the site of an ancient lake where clay minerals formed in water. The mudstone created an environment that could concentrate and preserve organic molecules and trapped them inside the fine grains of the sedimentary rock.
Freissinet helped lead a research team in 2015 that was able to identify organic molecules within the Cumberland sample.
The instrument detected an abundance of sulfur, which can be used to preserve organic molecules; nitrates, which are essential for plant and animal health on Earth; and methane composed of a type of carbon associated with biological processes on Earth.
“There is evidence that liquid water existed in Gale Crater for millions of years and probably much longer, which means there was enough time for life-forming chemistry to happen in these crater-lake environments on Mars,” said study coauthor Daniel Glavin, senior scientist for sample return at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in a statement.
Jamessnack
30 Mar 2025 - 06:31 pm
‘For the public to enjoy’
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The museum’s history starts in 1998, when Sheikh Faisal Bin Qassim Al Thani opened a building to the public on his farm some 20 kilometers (12 miles) north of Qatari capital Doha.
A distant relative of Qatar’s ruling family, founder and chairman of Al Faisal Holdings (one of Qatar’s biggest conglomerates), and a billionaire whose business acumen had him recognized as one of the most influential Arab businessmen in the world, Sheikh Faisal had already amassed a substantial private collection of historically important regional artifacts, plus a few quirky pieces of interest, allowing visitors an intimate look into Qatari life and history.
In an interview with Qatari channel Alrayyan TV in 2018, Sheikh Faisal said that the museum started as a hobby.
“I used to collect items whenever I got the chance,” he said. “As my business grew, so did my collections, and soon I was able to collect more and more items until I decided to put them in the museum for the public to enjoy.”
His private cabinet of curiosities has since evolved into a 130-acre complex. Through the fort-like entrance gate lies an oryx reserve, an impressive riding school and stables, a duck pond and a mosque built with a quirky leaning minaret. There’s now even a five-star Marriott hotel, two cafes and the Zoufa restaurant serving modern Lebanese cuisine.
Of course, there’s also the super-sized museum, with a recently-opened car collection housing everything from vintage Rolls-Royces to wartime Jeeps and colorful Buicks. Outside you’ll find peacocks roaming the grounds, and signs warning drivers to be aware of horses and ostriches.
Visitors to the FBQ museum are free to explore the grounds and can even enter the stables to pat the horses.
Kevinfoorn
30 Mar 2025 - 05:54 pm
Why there’s a huge collection of vintage cars stored in the middle of the desert
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Back at the turn of the 21st century, Qatar was a country with few cultural attractions to keep visitors and residents entertained. Yet the Sheikh Faisal Bin Qassim Al Thani Museum — known as the FBQ Museum — was a place that most people visited as an alternative to the then-still rather ramshackle National Museum of Qatar.
You had to make an appointment, and drive out into the desert, getting lost a few times along the way, but then you were welcomed to the lush Al Samriya Farm with a cup of tea and some cake. The highlight was being allowed into a space crammed full with shelves and vitrines holding all sorts of eclectic artifacts from swords to coins — with the odd car and carriage standing in the grounds.
It wasn’t necessarily the kind of museum you’d find elsewhere in the world, but it was definitely a sight that needed seeing.
Today, it has grown and now claims to be one of the world’s largest private museums. It holds over 30,000 items, including a fleet of traditional dhow sailboats, and countless carpets. There’s also an entire house that once stood in Damascus, Syria.
There are archaeological finds dating to the Jurassic age, ancient copies of the Quran, a section that details the importance of pearling within Qatar’s history, and jewelry dating to the 17th century.
There are also items from 2022’s FIFA World Cup in Qatar including replica trophies, balls used in the games, entry passes, football jerseys and even shelves full of slightly creepy dolls and children’s plush animals.
Some of the more disturbing exhibits include various items of Third Reich paraphernalia in the wartime room, and, strangely enough, several showcases of birds’ legs with marking rings on them. Basically, whatever you can think of, you have a very good chance of finding it here.
Rumor even has it that behind a locked door is a room filled with the late Princess Diana’s dresses and other memorabilia, accessible only to a select few visitors. Another door hides a room, no longer open to the public, filled with collectibles of the late Saddam Hussein.
Leonardhex
30 Mar 2025 - 05:44 pm
Everyone is talking about Greenland. Here’s what it’s like to visit
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A few months ago, Greenland was quietly getting on with winter, as the territory slid deeper into the darkness that envelops the world’s northerly reaches at this time of year.
But President Donald Trump’s musings about America taking over this island of 56,000 largely Inuit people, halfway between New York and Moscow, has seen Greenland shaken from its frozen Arctic anonymity.
Denmark, for whom Greenland is an autonomous crown dependency, has protested it’s not for sale. Officials in Greenland, meanwhile, have sought to assert the territory’s right to independence.
The conversation continues to intensify. A contentious March 28 visit to a US military installation by Usha Vance, the second lady, accompanied by her husband, Vice President JD Vance, was the latest in a series of events to focus attention on Trump’s ambitions for Greenland.
The visit was originally planned as a cultural exchange, but was shortened following complaints from Greenland Prime Minister Mute B. Egede.
Had the Vances prolonged their scheduled brief visit, they would’ve discovered a ruggedly pristine wildernesses steeped in rich Indigenous culture.
An inhospitable icecap several miles deep covers 80% of Greenland, forcing the Inuit to dwell along the shorelines in brightly painted communities. Here, they spend brutally cold winters hunting seals on ice under the northern lights in near perpetual darkness. Although these days, they can also rely on community stores.
The problem for travelers over the years has been getting to Greenland via time-consuming indirect flights. That’s changing. Late in 2024, the capital Nuuk opened a long-delayed international airport. From June 2025, United Airlines will be operating a twice-weekly direct service from Newark to Nuuk.
Two further international airports are due to open by 2026 — Qaqortoq in South Greenland and more significantly in Ilulissat, the island’s only real tourism hotspot.