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An enormous Martian cloud returns every spring. Scientists found out why

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A cloud longer than California streaks across Mars‘ ruddy cheek. It looks as though an impressionist painter loaded his palette knife with white and scraped a line across the canvas as far as the oily paint would travel.

This is not what astrophysicist Jorge Hernández Bernal first saw in 2018 when the Mars Express Visual Monitoring Camera(Opens in a new window) — affectionately known by the European Space Agency as the Mars webcam(Opens in a new window) — posted a new picture. To the average eye, it was grainy and inscrutable, with the resolution of a standard computer camera circa 20 years ago. But Bernal, who was studying Martian meteorology at the University of the Basque Country in Spain, immediately recognized the shadow as something else: a mysterious weather phenomenon happening on the Red Planet.

It wasn’t until researchers looked at the cloud with better equipment that Mars revealed the cloud in all its sprawling glory. The team dug deeper into photo archives, and discovered it had frequently been there. It was there through the aughts, and it was even there during NASA‘s Viking 2 mission(Opens in a new window) in the 1970s.

A low-resolution camera on the European Space Agency’s Mars Express probe first captured the enormous cloud in 2018.
Credit: ESA

The secret had been knowing when to look for it.

“There were people thinking ESA was faking it,” Bernal told Mashable. “It was a bit hard because I was really young at the time [of the discovery], and I was on Twitter trying to speak to people.”

Bernal and his team published their observations in 2020, dubbing it the Arsia Mons Elongated Cloud, or AMEC for short. With the cloud spanning 1,100 miles, scientists believe it could be the longest of its kind in the solar system. That work was followed with a second report, recently published(Opens in a new window) in the Journal of Geophysical Research: Planets, revealing just how the volcano makes this extraordinary cloud, alone in an otherwise cloudless southern Mars that time of year.

“There were people thinking ESA was faking it.”

How scientists discovered Mars’ long cloud

For decades, the icy cloud arrived at sunrise on the western slope of Arsia Mons(Opens in a new window), an extinct volcano. The once lava-spewing ancient mountain is about 270 miles wide at the base and soars 11 miles into the sky. It dwarfs Mauna Loa, the largest Earth volcano, which is about half its height.

The curious case of the gigantic cloud is how it escaped notice for so long. But some of the spacecraft around Mars, such as NASA’s Mars Reconnaissance Orbiter, are in orbits synchronized with the sun, meaning their cameras can’t take pictures until the afternoon. By that time, the fleeting cloud, which lasts only about three hours in the morning, is already gone.

The Mars Webcam wasn’t originally meant for science. Its purpose was to provide visual confirmation that ESA’s Beagle 2 lander(Opens in a new window) had separated from the Mars Express spacecraft in 2003. In hindsight, the space agency is glad it decided to turn the basic camera back on(Opens in a new window).

Mars Express spacecraft orbiting Mars
A simple camera not even intended for science on the European Space Agency’s Mars Express spacecraft photographed the enormous cloud.
Credit: ESA

Just as southern Mars experiences spring, the cloud grows and stretches, making a wispy tail like a steam locomotive, over the mountain’s summit. Then, in a matter of hours, the cloud completely fades away in the warm sunlight.

For a young scientist working on his doctorate degree, the natural wonder became a sort of muse. While the realist in him said that recreational space travel is impractical — perhaps even unethical given the world’s climate problems — he couldn’t help but try to draw what the cloud might look like from the ground.

“I keep imagining how it would be for a little civilization to have this huge cloud every year at the same time, like maybe the solstice is something for them like a coat,” he said, smiling. “This is the imagination part.”

Why Mars’ Arsia Mons makes the gigantic cloud

So what makes this strange, stringy cloud?

For starters, it’s not smoke billowing from a volcanic eruption. Scientists have long-known the volcanoes of the Red Planet(Opens in a new window) are dead. Rather, it’s the so-called “orographic effect:” the physics of air rising over a mountain or volcano.

The researchers ran a high-resolution computer simulation of Arsia Mons’ effect on the atmosphere. Strong winds whip at its foot, making gravity waves. Moist air is then temporarily squeezed and driven up the mountainside. Those drafts blow up to 45 mph, forcing the temperature to plunge by more than 54 degrees Fahrenheit. This allows water to condense and freeze at about 28 miles above the volcano’s peak.


“I keep imagining how it would be for a little civilization to have this huge cloud every year at the same time, like maybe the solstice is something for them like a coat.”

Arsia Mons cloud returning year after year
The enormous Arsia Mons cloud returns year after year in Mars’ springtime for about 80 days.
Credit: ESA

For about five to ten percent of the Martian year, the atmosphere is just right(Opens in a new window) to make the cloud, with the dusty sky helping moisture cling to the air. Too early in the year and the air would be too dry, according to the team’s model. Too late in the year and the climate would be too warm for water condensation.

But though the scientists’ simulation was successful in forming the cloud under Arsia Mons’ unique conditions, it could not replicate the cloud’s lengthy tail. Scientists say that’s the biggest question of the moment — a mystery that could be solved with spectrometers, devices on spacecraft that identify the kinds of particles in a substance. A closer study of the cloud’s water ice might give researchers more clues.

“I would like to see this cloud with my eyes, but I know where my place is,” Bernal said. “Sometimes we think of space like a utopia. I am happy looking at it from [Earth, through] my spacecraft.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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