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Chesterinfek
11 Apr 2025 - 01:40 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.”
Virgilcaw
11 Apr 2025 - 12:58 pm
Space, time: The continual question
If time moves differently on the peaks of mountains than the shores of the ocean, you can imagine that things get even more bizarre the farther away from Earth you travel.
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To add more complication: Time also passes slower the faster a person or spacecraft is moving, according to Einstein’s theory of special relativity.
Astronauts on the International Space Station, for example, are lucky, said Dr. Bijunath Patla, a theoretical physicist with the US National Institute of Standards and Technology, in a phone interview. Though the space station orbits about 200 miles (322 kilometers) above Earth’s surface, it also travels at high speeds — looping the planet 16 times per day — so the effects of relativity somewhat cancel each other out, Patla said. For that reason, astronauts on the orbiting laboratory can easily use Earth time to stay on schedule.
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For other missions — it’s not so simple.
Fortunately, scientists already have decades of experience contending with the complexities.
Spacecraft, for example, are equipped with their own clocks called oscillators, Gramling said.
“They maintain their own time,” Gramling said. “And most of our operations for spacecraft — even spacecraft that are all the way out at Pluto, or the Kuiper Belt, like New Horizons — (rely on) ground stations that are back on Earth. So everything they’re doing has to correlate with UTC.”
But those spacecraft also rely on their own kept time, Gramling said. Vehicles exploring deep into the solar system, for example, have to know — based on their own time scale — when they are approaching a planet in case the spacecraft needs to use that planetary body for navigational purposes, she added.
For 50 years, scientists have also been able to observe atomic clocks that are tucked aboard GPS satellites, which orbit Earth about 12,550 miles (20,200 kilometers) away — or about one-nineteenth the distance between our planet and the moon.
Studying those clocks has given scientists a great starting point to begin extrapolating further as they set out to establish a new time scale for the moon, Patla said.
“We can easily compare (GPS) clocks to clocks on the ground,” Patla said, adding that scientists have found a way to gently slow GPS clocks down, making them tick more in-line with Earth-bound clocks. “Obviously, it’s not as easy as it sounds, but it’s easier than making a mess.”
Jamesfaf
11 Apr 2025 - 12:50 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.
Scottomili
11 Apr 2025 - 12:45 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.
Andreses
11 Apr 2025 - 12:35 pm
Lunar clockwork
What scientists know for certain is that they need to get precision timekeeping instruments to the moon.
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Exactly who pays for lunar clocks, which type of clocks will go, and where they’ll be positioned are all questions that remain up in the air, Gramling said.
“We have to work all of this out,” she said. “I don’t think we know yet. I think it will be an amalgamation of several different things.”
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Atomic clocks, Gramling noted, are great for long-term stability, and crystal oscillators have an advantage for short-term stability.
“You never trust one clock,” Gramling added. “And you never trust two clocks.”
Clocks of various types could be placed inside satellites that orbit the moon or perhaps at the precise locations on the lunar surface that astronauts will one day visit.
As for price, an atomic clock worthy of space travel could cost around a few million dollars, according Gramling, with crystal oscillators coming in substantially cheaper.
But, Patla said, you get what you pay for.
“The very cheap oscillators may be off by milliseconds or even 10s of milliseconds,” he added. “And that is important because for navigation purposes — we need to have the clocks synchronized to 10s of nanoseconds.”
A network of clocks on the moon could work in concert to inform the new lunar time scale, just as atomic clocks do for UTC on Earth.
(There will not, Gramling added, be different time zones on the moon. “There have been conversations about creating different zones, with the answer: ‘No,’” she said. “But that could change in the future.”)
Leonardgrile
11 Apr 2025 - 11:51 am
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.
Johnnievar
11 Apr 2025 - 11:49 am
Curiosity rover makes ‘arguably the most exciting organic detection to date on Mars’
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The NASA Curiosity rover has detected the largest organic molecules found to date on Mars, opening a window into the red planet’s past. The newly detected compounds suggest complex organic chemistry may have occurred in the planet’s past — the kind necessary for the origin of life, according to new research.
The organic compounds, which include decane, undecane and dodecane, came to light after the rover analyzed a pulverized 3.7 billion-year-old rock sample using its onboard mini lab called SAM, short for Sample Analysis at Mars.
Scientists believe the long chains of molecules could be fragments of fatty acids, which are organic molecules that are chemical building blocks of life on Earth and help form cell membranes. But such compounds can also be formed without the presence of life, created when water interacts with minerals in hydrothermal vents.
The molecules cannot currently be confirmed as evidence of past life on the red planet, but they add to the growing list of compounds that robotic explorers have discovered on Mars in recent years. A study detailing the findings was published Monday in the journal Proceedings of the National Academy of Sciences.
The detection of the fragile molecules also encourages astrobiologists that if any biosignatures, or past signs of life, ever existed on Mars, they are likely still detectable despite the harsh solar radiation that has bombarded the planet for tens of millions of years.
“Ancient life, if it happened on Mars, it would have released some complex and fragile molecules,” said lead study author Dr. Caroline Freissinet, research scientist at the French National Centre for Scientific Research in the Laboratory for Atmospheres, Observations, and Space in Guyancourt, France. “And because now we know that Mars can preserve these complex and fragile molecules, it means that we could detect ancient life on Mars.”
Frankgot
11 Apr 2025 - 10:46 am
Lunar clockwork
What scientists know for certain is that they need to get precision timekeeping instruments to the moon.
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Exactly who pays for lunar clocks, which type of clocks will go, and where they’ll be positioned are all questions that remain up in the air, Gramling said.
“We have to work all of this out,” she said. “I don’t think we know yet. I think it will be an amalgamation of several different things.”
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Atomic clocks, Gramling noted, are great for long-term stability, and crystal oscillators have an advantage for short-term stability.
“You never trust one clock,” Gramling added. “And you never trust two clocks.”
Clocks of various types could be placed inside satellites that orbit the moon or perhaps at the precise locations on the lunar surface that astronauts will one day visit.
As for price, an atomic clock worthy of space travel could cost around a few million dollars, according Gramling, with crystal oscillators coming in substantially cheaper.
But, Patla said, you get what you pay for.
“The very cheap oscillators may be off by milliseconds or even 10s of milliseconds,” he added. “And that is important because for navigation purposes — we need to have the clocks synchronized to 10s of nanoseconds.”
A network of clocks on the moon could work in concert to inform the new lunar time scale, just as atomic clocks do for UTC on Earth.
(There will not, Gramling added, be different time zones on the moon. “There have been conversations about creating different zones, with the answer: ‘No,’” she said. “But that could change in the future.”)
Gordonmuh
11 Apr 2025 - 10:41 am
‘A whole different mindset’
Accurate clockwork is one matter. But how future astronauts living and working on the lunar surface will experience time is a different question entirely.
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On Earth, our sense of one day is governed by the fact that the planet completes one rotation every 24 hours, giving most locations a consistent cycle of daylight and darkened nights. On the moon, however, the equator receives roughly 14 days of sunlight followed by 14 days of darkness.
“It’s just a very, very different concept” on the moon, Betts said. “And (NASA is) talking about landing astronauts in the very interesting south polar region (of the moon), where you have permanently lit and permanently shadowed areas. So, that’s a whole other set of confusion.”
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“It’ll be challenging” for those astronauts, Betts added. “It’s so different than Earth, and it’s just a whole different mindset.”
That will be true no matter what time is displayed on the astronauts’ watches.
Still, precision timekeeping matters — not just for the sake of scientifically understanding the passage of time on the moon but also for setting up all the infrastructure necessary to carry out missions.
The beauty of creating a time scale from scratch, Gramling said, is that scientists can take everything they have learned about timekeeping on Earth and apply it to a new system on the moon.
And if scientists can get it right on the moon, she added, they can get it right later down the road if NASA fulfills its goal of sending astronauts deeper into the solar system.
“We are very much looking at executing this on the moon, learning what we can learn,” Gramling said, “so that we are prepared to do the same thing on Mars or other future bodies.”
Davidlut
11 Apr 2025 - 10:19 am
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.