Wednesday, December 2, 2020

Polar scientists wary of impending satellite gap

It's satellites that have tracked the loss of ice in the Antarctic and the Arctic
photo Rob Larter/BAS

From BBC by Jonathan Amos

There is going to be a gap of several years in our ability to measure the thickness of ice at the top and bottom of the world, scientists are warning. 

The only two satellites dedicated to observing the poles are almost certain to die before replacements are flown.
This could leave us blind to some important changes in the Arctic and the Antarctic as the climate warms.

The researchers have raised their concerns with the European Commission and the European Space Agency.
A letter detailing the problem - and possible solutions - was sent to leading EC and Esa officials this week; and although the US space agency (Nasa) has not formally been addressed, it has been made aware of the correspondence.

At issue is the longevity of the European CryoSat-2 and American IceSat-2 missions.
These spacecraft carry instruments called altimeters that gauge the shape and elevation of ice surfaces.
They've been critical in recording the loss of sea-ice volume and the declining mass of glaciers.

Image copyright ESA/NASA
image captionArtwork: CryoSat-2 (top) and IceSat-2 (bottom) will hopefully last until mid-decade


What's unique about the satellites is their orbits around the Earth.
They fly to 88 degrees North and South from the equator, which means they see the entire Arctic and Antarctic regions, bar a small circle about 430km in diameter at the poles themselves.

In contrast, most other satellites don't usually go above 83 degrees.
As a consequence, they miss, for example, a great swathe of the central Arctic Ocean and its frozen floes.

The worry is that CryoSat-2 and IceSat-2 will have been decommissioned long before any follow-ups get launched.

CryoSat-2 is already way beyond its design life. It was put in space in 2010 with the expectation it would work for at least 3.5 years.
Engineers think they can keep it operating until perhaps 2024, but battery degradation and a fuel leak suggest not for much longer.

IceSat-2 was launched in 2018 with a design life of three years, but with the hope - and expectation - it can operate productively deep into the decade.


The satellites' orbits leave only a very small hole in their measurements at the poles
ESA

"Without successful mitigation, there will be a gap of between two and five years in our polar satellite altimetry capability," the scientists' letter states."
This gap will introduce a decisive break in the long-term records of ice sheet and sea-ice thickness change and polar oceanography and this, in turn, will degrade our capacity to assess and improve climate model projections."

The only satellite replacement currently in prospect is the EC/Esa mission codenamed Cristal.
It will be like Cryosat, although with much greater capability thanks to a dual-frequency radar altimeter.

Industry has started work on the spacecraft but it won't launch until 2027/28, maybe even later because full funding to make this date a reality is not yet in place.

Dr Josef Aschbacher, the director of Earth observation at Esa, said his agency was working as fast as it could to plug the gap.
"This is a concern; we recognise it," he told the BBC. "We've put plans in motion to build Cristal as quick as we can. Despite Covid, despite heavy workloads and video conferences by everyone - we have gone through the evaluation... and Cristal was kicked off in early September."

IMAGE COPYRIGHTNAS Aimage caption An option for Europe?
The Americans flew a stop-gap laser altimeter on aeroplanes

Just over 10% of the near-600 signatories to the letter are American scientists.

Dr Thomas Zurbuchen, the head of science at Nasa, is not being sent the letter because it is primarily aimed at European funders - and most of the signatories are European.
Nonetheless, Dr Zurbuchen is aware of the letter and its contents.
He said he was hopeful any polar gap could be plugged or minimised.
"I think there are multiple options at this moment in time that we can deploy to that end, in partnership or otherwise," he commented.

One of those solutions in Europe would be to run a version of Nasa's IceBridge project.

This was an airborne platform that the US agency operated in the eight years between the end of the very first IceSat mission in 2010 and the launch of IceSat-2 in 2018.

An aeroplane flew a laser altimeter over the Arctic and the Antarctic to gather some limited data-sets that could eventually be used to tie the two IceSat missions together.

There are many who think a European "CryoBridge" is the most affordable and near-term option to mitigate the empty years between CryoSat-2 and Cristal.

The cost of manufacture of the airborne radar altimeter could be accomplished for perhaps €5m (£4.5m), scientists believe, but its design and fabrication would likely take two years.
Such a project would therefore have to get under way relatively soon.
It would, of course, also need an operational budget.

The signatories to the letter sent to the EC and Esa include leading scientists using CryoSat and IceSat data, the president of the International Glaciology Society, and lead authors on the United Nations' Intergovernmental Panel on Climate Change, which prepares the authoritative state-of-the-climate reports for world governments.
 
Links :

Tuesday, December 1, 2020

US (NOAA) layer update in the GeoGarage platform

12 nautical raster charts updated

400 years on, the Pilgrims get a reality check

Assailed by storms during its two-month-long Atlantic crossing, the Mayflower landed at Cape Cod on November 11, 1620.
After finding no suitable home, the Pilgrims sailed to Plymouth Bay, ferried ashore in small groups, and settled in the remains of a Native American village.
Photograph By Detroit Publishing Company, Library Of Congress


From National Geographic by Bill Newcott

From the signing of the Mayflower Compact to the landing at Plymouth Rock, the grade-school story of the Pilgrims doesn’t quite square with the facts.
The real story of the Pilgrims and the Indigenous people they encountered is more complicated, though no less human, than the grade-school narrative we're familiar with.

The good people of Plymouth, Massachusetts, had big plans for 2020, the 400th anniversary of the Pilgrims’ arrival in New England.
The town’s nonprofit living history museum—known since its 1947 founding as Plimoth Plantation—had spent considerable time and some expense rebranding itself Plimoth Patuxet Museums, to more accurately represent the link between the Pilgrims and the Native American tribe whose village they occupied.
More than $11 million had been invested in restoring Mayflower II, the reproduction ship that has floated in Plymouth Harbor since 1957.
Tens of thousands of spectators were expected for the renovated ship’s triumphant return from dry dock, including a rendezvous with Boston’s 223-year-old U.S.S.
Constitution
, and an escort of Native Americans paddling dugout canoes.

Millions were expected to attend the biggest summer-long party Plymouth had ever seen.
Then, last spring, COVID-19 came and ate all the birthday cake.

Then again, the story of the Pilgrims’ early years in Massachusetts and their relationship with the Indigenous people they met there has always been fraught with unexpected twists.
The Europeans found their foothold in the ruins of a village emptied by the ravages of plague.
Barely surviving their first winter, they feared being overrun by the Native Americans they saw peering at them from the forest—only to find in them an unlikely military and trade partner.
And through it all, in every direction, the land was stained by treachery, bloodshed, and betrayal.

For the hundreds of thousands of annual visitors to the Plimoth Patuxent Museums, those hard truths can be difficult to square with the traditional grade-school narrative many of us grew up with—of benevolent Pilgrims and amiable Indians seated around a big Thanksgiving picnic table.
But the real story is, if a bit more complicated, no less human.
New discoveries have revealed not only the extent of conflict between the two cultures, but also the surprising levels of social intimacy they shared.




A crowd of onlookers turned out on August 10 to see the Mayflower II return to Plymouth Harbor after three years of restoration at Connecticut’s Mystic Seaport.
But it was a far cry from the hundreds of thousands of visitors the town was expecting before COVID-19 kept them away.
Photograph By Scott Eisen, Getty

Stormy beginnings

Despite their haloed image, the Pilgrims were a decidedly motley crew.
Staunch Protestant Puritans, they had been forced into exile in the Netherlands around 1607 for resisting King James’s Church of England.
But the strait-laced refugees were doubly unhappy in the Netherlands, which then as now was a fairly freewheeling party scene.
Luckily, King James was anxious to populate the new North American colonies, so he let the Pilgrims sail there to practice their renegade religion undisturbed.
The voyage would be financed by investors, and in return the Pilgrims would send furs and other goods back to England for sale.

After a few false starts, the Mayflower set sail from Plymouth, England, on September 6, 1620.
For 65 miserable days the huddled passengers endured storms, sickness, and even the births of two children, a pair of boys named Oceanus Hopkins and Peregrine White.
Weather forced them north of their intended destination along the Hudson River, then part of the British colony of Virginia.
Finally, on November 9, land was sighted: the tip of Cape Cod.


The Mayflower set sail from Plymouth, England, on September 6, 1620.
“We loosed from Plymouth having been kindly entertained and courteously used by divers friends there dwelling,” wrote Pilgrim leader Edward Winslow.
Photograph by Hulton Archive, Getty

But before anyone could set foot in the New World, Pilgrim leader John Carver had a bit of last-minute paperwork.
Unlike Virginia, the land that spread before the Pilgrims had, as far as Carver knew, no formal charter from King James, and thus no effective law.
He became alarmed when some of the non-Puritans among them gleefully began to anticipate becoming a law unto themselves.

Quickly, the Pilgrim leadership drafted a rudimentary constitution to “combine our selves together into a civil body politick”—which would, through democratic process, enact “just and equal laws…for the general good of the Colony.”

“This is almost certainly not the room where the Mayflower Compact was signed,” says Richard Pickering, chief historian for Plimoth Patuxet Museums.
We are standing in a relatively large cabin at the back end of Mayflower II.Countless paintings depict finely dressed Pilgrim fathers gathered in just such a cabin and seated, Last Supper-like, around a large table, wielding feathery quills as they sign their document of self-government.

“First of all,” Pickering explains, “these were crew quarters, and the crew didn’t really even like the Pilgrims. All 102 of them were crammed onto the deck below this.”

In reality, the signing was probably more of an informal affair, Pickering says.
“The document was carried from person to person: ‘Here—sign this!’ There was also a bit of coercion involved. You weren’t getting off the boat until you signed.”

Coerced or not, the Mayflower Compact stands as a landmark document in North American history.
Although Native American tribes had organized into governments for centuries, the Pilgrims’ compact was the New World’s first written constitution of self-government by Europeans.

A tale of two rocks

Cape Cod curls like a flexed arm, its angry fist railing against the assault of New England winters.
At its apex stands Provincetown’s 110-year-old Pilgrim Memorial, a 250-foot tower commemorating the Pilgrim’s first landing nearby.
Incongruously based on the 14th-century Torre del Mangia in Siena, Italy, the monument looks as if its creators had somehow confused Thanksgiving with Columbus Day.
Atop its 116 steps and ramps, the New World of the Pilgrims comes into focus.

Current nautical map of Cape Cod, NOAA with the GeoGarage platform

To the east, Atlantic surf pounds Cape Cod National Seashore.
Down the coast lies First Encounter Beach, site of the first face-off between the newly-arrived Pilgrims and the Wampanoag.
That initial meeting ended in a brief, ineffectual volley of arrows and gunshots.
It was the beginning of a complicated relationship that began in conflict, grew into a shaky political alliance, and finally devolved into open hostilities and centuries of mistrust.
Even today, the two sides are, in a sense, trying to work out their troubled shared history.

Some 32 miles west, outlined against the low afternoon sun, lies the Pilgrims’ ultimate destination: the protected natural harbor of Plymouth Bay.
The Pilgrims wrote about their adventures in exquisite detail, yet never once did they mention Plymouth Rock, traditional site of their second landing a few weeks after their arrival.
Not until 1741 did the elderly son of a Pilgrim bestow that honor on the modest boulder that now sits under a granite canopy on Plymouth’s waterfront.

So breathless was the schoolhouse lore of Plymouth Rock that, as a young boy on a New England vacation with my family, I fully expected to see a monolith the size of Gibraltar—only to discover a hunk of stone that resembled a big, gray beanbag chair.
Never a very large rock, the thing is today about one-third its original size, the rest having been chipped away by souvenir seekers.


The Roman Doric portico that shelters the traditional Plymouth Rock was already 30 years old when these 1950s visitors made the pilgrimage.
Built to celebrate the 300th anniversary of Ma… 
Photograph By Douglas Grundy, Three Lions/Getty

From Plymouth Rock I climb a steep concrete stairway up Cole’s Hill, a bluff overlooking Plymouth Bay.
Most years the hill rings with the laughter of tourists snapping selfies, but in truth there are few spots more mournful than this, a place long associated with death and despair.

Ascending this hill, the first Pilgrim expedition discovered a literal ghost town: a Native village, empty for three years or so.
Many of its huts were still populated by skeletal corpses of Patuxet who had been wiped out by a hemorrhagic disease—probably smallpox brought by earlier European traders.

Still, the grotesque site sat on an easily defensible hillside beside a rushing stream.
Despite its clearly awful history, the Pilgrims settled there, praising God for his provision.

But praise soon turned to mourning.
At the lip of Cole’s Hill stands a marble sarcophagus containing a mass of commingled bones—assumed to be those of the 52 Pilgrim men, women, and children who died of disease and exposure that first savage winter.
They’d been hastily buried on this site in the dead of winter, only to have their remains exposed following heavy rains in the late 1800s.

The melancholy spirit of Cole’s Hill deepens just a few feet away with a more modest monument, a plaque attached to a rock commemorating a “National Day of Mourning.” Each Thanksgiving, representatives of many Native American tribes gather here to remember, in the words of the plaque, “the genocide of millions of their people, the theft of their lands, and the relentless assault on their culture.” (Today, traditional indigenous beliefs are a powerful tool for understanding COVID-19.)

The sadness of this place is palpable.

Sole survivor


After those initial burials on Cole’s Hill, the Pilgrims established a new cemetery higher in the hills, just beyond the wooden palisade they built around their settlement.
Burial Hill remains a quiet, tree-shrouded retreat, a relatively easy climb from the waterfront.
From its summit, through the trees and headstones, the sweeping view of Plymouth Bay and its barrier sand bars affirms why this made such a likely spot for defense from attack by sea.

The surrounding woods, however, were another story.

Turning south atop Burial Hill, I look toward another hill just across the narrow and fast-moving Town Brook.
For months in early 1621, Pilgrims stood where I’m standing and gazed across the creek, watching nervously as the concerned faces of Wampanoag tribe members stared back at them.

Then, on March 16, a Native American strode boldly through the gate of Plimoth, raised his hand, and greeted them in English.
His name was Samoset, and he’d learned the foreigners’ language from traders.
He returned with another Native American named Tisquantum, more commonly known as Squanto.
This man not only spoke perfect English, but years earlier he’d been kidnapped and taken to Europe as a slave.

Squanto had gained his freedom and returned to North America as a guide, only to learn that his misfortune had probably saved his life: He was, it turned out, a member of the Patuxet tribe, which in his absence had been wiped out by plague.
Now, the Patuxet’s sole survivor stood in the Pilgrims’ new settlement—built on the ruins of his dead family’s home.
(Related: Native American imagery abounds, but the people are often forgotten.)


With Squanto serving as translator, the Pilgrims negotiated a peace treaty with Massasoit, leader of the Wampanoag—a loose confederation of several area tribes, including the now-extinct Patuxet.
Most significantly, the two parties agreed to provide mutual defense—a bond that benefited both Massasoit, who was facing resistance from rivals, and the Pilgrims, who would have been helpless in the face of any concerted attack.

It was that treaty, in fact, that led to the fabled first Thanksgiving.
As the Pilgrims celebrated their first harvest in November 1621, they fired their muskets into the air.
Legend has it that Massasoit, fearing his allies were under attack, rushed to the scene with a group of warriors.
Relieved to discover all was well, the story goes, the group stayed for dinner.
More likely, Plimoth historian Pickering says, Massoit and his men, who were accustomed to hearing gunshots from military drills, dropped by on a diplomatic mission, bringing along five deer as a gift.

'This isn’t Disneyland'


As fall foliage erupts in yellows and reds, the Plimoth Patuxet Museum’s parking lot should be jammed with cars from every state east of the Mississippi.
Instead, a hundred or so vehicles, virtually all with Massachusetts plates, bunch near the entrance.
The limited numbers are no surprise.
Just to visit here from my home in Delaware I first had to fill out an online Massachusetts State Visitor’s Form and bring documentation of a recent negative COVID-19 test.

I’m greeted near the visitors center by Darius Coombs, a Wampanoag tribe member and a museum staffer for more than 30 years.
As I zip up my windbreaker against the fall chill, Coombs seems entirely comfortable in his traditional dress: moose hide moccasins and deerskin leggings, breechcloth and mantle.
Around his shoulders is draped a beaver pelt coat, worn with the fur facing in to capture and preserve body heat.
Over his arm hangs the skin of a black wolf.

Coombs leads me to a clearing with a pinwheel-shaped pattern staked out on the ground—the outline of what the Wampanoag call a snail house, first built in these parts some 12,000 years ago.
COVID willing, it will be built in time for next season’s visitors.

The museum’s reconstructed circa-1620 Wampanoag village, a scattering of bark-covered houses called wetu, sits on the shore of the Eel River.
By the water, a tribe member scrapes a mishoon, a dugout canoe, from a tree trunk.
Nearby, a massive 46-foot mishoon—carved from a seven-ton tree—lies nearly completed.

Like Coombs, all the skin-wearing workers here are Wampanoag.
“You can’t wear skins if you’re not Wampanoag,” he says.
“When we go hunting for these animals, we do a ceremony for them. You’re taking the animal’s life, so it becomes part of what we are. This is important to us. This isn’t Disneyland.”

I can’t help but notice that Coombs’s accent often carries echoes of his Boston childhood (“…paht of what we ah”).
When I suggest his speech would never pass muster in a Hollywood movie about Native Americans, he smiles at the memory of a documentary crew that recently asked his help making a film about Wampanoag children at the time of the Pilgrims.

He agreed, with one condition: “I told them they’d also have to show our children today—wearing jeans and sneakers and riding their bikes.
I don’t want kids to think our children only existed in the past.
They are here now, and they’re just like any other kids.”

A startling discovery

I am walking up The Street, as the one and only avenue in early Plimoth Colony was known.
The unpaved, eroded course is flanked by rustic timber houses with thatched roofs.
Behind many of them are small gardens, tended by men and women in period dress, diligently digging, hoeing, or pruning.

The original Street lies somewhere below the busy pavement of modern-day Plymouth’s Leyden Street.
This replica runs up a similar hillside three miles south of the original, through the middle of the reconstructed Plimoth Plantation.

Behind one house I spot a red-bearded man in a bright yellow smock, hard at work.
“I’m hoeing dung,” he cheerfully declares with a smile and a lilting British accent.
He tells me he is Edward Winslow, a signatory of the Mayflower Compact, three-time governor of the colony, and author of a seminal Pilgrim account, Good Newes From New England.
“We use this dung to fertilize our little garden beds,” he says.
“But in the fields, for the corn, we use fish, as the Indians showed us.
I would not wish to have enough animals to create enough dung to cover our corn fields!”

He chats animatedly about encouraging news from Jamestown and the death of King James.
I can tell he could go on all afternoon, but I’ve been told I’m free to ask the museum’s historical interpreters to break character and talk about their real selves—a radical departure from the museum’s strict stay-in-character rules.
Checking to make sure no other visitors are within earshot, I ask Edward Winslow to re-enter the 21st century.

The twinkle in his eyes remains, but the voice abruptly shifts from 17th-century English to modern-day suburban Bostonian.

Originally launched from a British shipyard in 1957—a gift to America in gratitude for its sacrifices during World War II—Mayflower II returns to Plymouth Harbor August 10.
A gala celebration in Boston Harbor had to be scrapped due to the COVID-19 pandemic.
Photograph By Scott Eisen, Getty

“I’m from Plymouth,” says Joshua Bernard, who started here in 2012 while working his way through the University of Massachusetts at Amherst.
“I went to UMass for linguistics, then polished it by doing research while working here.”

Bernard explains he’s sprinkling his archaic language with a Worcestershire accent.
“I had a woman from England go into a full regional dialect with me,” he says.
“That was a personal win.”

Too soon, it’s time to let Joshua Bernard return to Edward Winslow.
“A pleasure,” says the 400-year-old Pilgrim.
He turns back to his dung pile.

As I exit through the broad opening in the replica palisade, I notice a loaf-shaped, bark-covered Wampanoag wetu house about 20 yards away.
New archaeological research suggests the house might belong much closer.
(A newfound survivor camp may explain fate of the famed Lost Colony of Roanoke.)

Digging at the foot of Burial Hill in 2019, a University of Massachusetts team discovered a line of dark soil that is almost certainly the remains of the colony’s original palisade—the first actual remnant of Plimoth ever found.
But the most exciting find was hard against the outside of that wall: the remains of what appears to be a Wampanoag tool-making site.

“Literally, these two cultures were living a few feet away from each other,” says Jade Luiz, curator of collections at Plimoth Patuxet Museums, where an entire gallery is given to a history of the Wampanoag and their interactions with the Europeans.
“That rewrites a lot of what we thought we knew about them.”

Baptized in blood

The Wampanoag showed the Pilgrims how to farm New England’s thin soil and also traded furs the Pilgrims desperately needed in order to pay their creditors back in London.
Beyond that, theirs was a relationship baptized in blood.
As part of their mutual defense agreement, the two groups fought side by side against Massasoit’s enemies.
Pilgrim leaders even lured two men from a rival tribe to a supposed private dinner—and promptly stabbed them both to death.

“Life was brutal,” says historian David Silverman, a professor of history at George Washington University and author of This Land is Their Land.
“If you walked into either the Plymouth colony or a Wampanoag village during the 1600s, the first thing you’d see at the entrance would be severed body parts and decapitated heads.”

He does not envy the stewards of Plimoth Patuxet Museums as they try to balance family-friendly experiences with cold-hearted history.

“Good history,” he says, “upsets everyone.”

The Pilgrim-Wampanoag alliance lasted about 50 years.
After the death of Massasoit in 1662, his son Metacom, also known as King Phillip, began to push back against European encroachment.
In the course of King Philip’s War, from 1675 to 1678, Native Americans raided more than half the European settlements from Connecticut to Maine.
The colonists responded by forming an armed militia, the first in colonial history.

In the end, the Europeans prevailed.
The systematic conquest of America’s Indigenous peoples had begun in earnest.

But is it wrong to memorialize that one bright moment when people of two very different worlds found a way to coexist?
Not in the opinion of scholars like John Turner, professor of religious studies at George Mason University and author of They Knew They Were Pilgrims.
“When you think about it, 50 years of peace is a pretty long time,” says Turner.
“Even though the alliance between the Pilgrims and the Wampanoag was one of necessity and not of friendship, it’s nevertheless worth celebrating.”

Monday, November 30, 2020

Chinese manned deep-sea submersible gets rare look at deepest ocean depths, the Mariana Trench

A Chinese scientist with China's Fendouzhe submersible mission on Wednesday released some footages shot at the bottom of the Mariana Trench, the deepest oceanic trench on Earth.

From Science Times by Erika P.

In a live-streamed footage, China has broken its record for the deepest manned dive into the world's deepest oceanic trench. The Chinese submersible, named "Fendouzhe," or "Strive," descended on the seabed of Mariana Trench on Tuesday morning after one month of sailing from Hainan province in China.

The submersible dived an estimated 10,909 meters (35,790 feet) into the Mariana Trench in the western Pacific Ocean with three researchers on board, according to state broadcaster CCTV.

 
China's Deep-Sea Manned Submersible

The recent dive has beaten its record by over 800 meters (2,624 feet) and missed out on beating the world record for the deepest dive in Mariana Trench, which was set by American undersea explorer Victor Vescovo.

He claims to have reached a depth of 10,927 meters (35,853 feet) last year in May.

This week, video footage from the underwater camera showed that the green and white Chinese submersible is moving through dark waters in the Mariana Trench surrounded by clouds of sediments as it touches down the seabed.

According to a report by Phys.org, China has conducted multiple dives of Fendouzhe earlier this month and landed on the deepest known point of the trench, which is the Challenger Deep, just a few meters higher than the world record of Vescovo.

For the first time, the world witnessed the first live video from Challenger deep as the Chinese submersible descends into the Earth's deepest oceanic trench.

Fendouzhe has robotic arms that it uses to collect biological samples and sonar eyes to identify its surroundings using sound waves.

Since it is carrying too much equipment, the engineers had to add a bulbous forehead or a protrusion that contains buoyant materials to keep its balance.

 
Rare Earths: Deep-Sea Resources

The country's goal aside from scientific exploration is to explore the abundance that is hidden in the deep ocean, said Ye Cong, the submersible's designer.

He told the state-run media that they need high-tech diving equipment to help better draw a "treasure map" of the deep part of the ocean.

In 2018, Japan did a remarkable discovery of rare earth resources on its small island of Minamitori in the Pacific Ocean where it is said that recoverable resources are 1,000 times more than on land. 

"The ocean floor is a whole new world.
If we don't explore this world, others will explore it," the CCTV said.

Rare earths are used for the production of high-tech products like smartphones, missile systems, and radar, which is currently controlled by China, according to CNN. Its capital is working hard to retain its dominance in this industry, reaching a record-breaking quota in July that is as high as 140,000 tons (140 million kilograms).

That being said, China is participating in joint research and training with the International Seabed Authority, to train professionals on deep-sea technology and conduct further research on mining for rare earths found in the deep sea.

Fendouzhe is seen to set the standards for the future of deep-sea vessels of China.

But Zhu Min, one of the researchers, said that it would take two trials before the success of the submersible's mission is declared.

Links :

Sunday, November 29, 2020

Satellites : LeoView visualization

Founded in 2015, LeoLabs relies on radar stations located in Alaska, Texas and New Zealand to track low orbit satellite constellations (i.e. telecommunications and Earth observation satellites such as SPOT, Sentinel or Pleiades).
It offers its monitoring and potential conflict detection services in the form of subscriptions via a web interface : LeoView.
Good news for the simple curious that we are, this interface, with reduced functions, is also accessible to the general public without registration.
On LeoView, anyone can follow all the satellites in orbit in real time, search by satellite name, country of origin, altitude, etc., and display a layer of more than 15,000 pieces of debris.
Eventually, the company will multiply its radars (a fourth is under construction in Costa Rica) in order to amplify and refine its measurements.
Admittedly, the scales of representation of the satellites are not respected, which gives a false impression of space congestion, but the visualisation of the virtual globe remains very fluid and impressive.
To be tested, if only for fun.