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Mars is a seismically active world, first results from NASA's InSight lander reveal – Space.com

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Mars may be cold and dry, but it’s far from dead.

The first official science results from NASA’s quake-hunting InSight Mars lander just came out, and they reveal a regularly roiled world.

“We’ve finally, for the first time, established that Mars is a seismically active planet,” InSight principal investigator Bruce Banerdt, of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, said during a teleconference with reporters Thursday (Feb. 20).

Related: Mars InSight in photos: NASA’s mission to probe Martian core

Martian seismicity falls between that of the moon and that of Earth, Banerdt added.

“In fact, it’s probably close to the kind of seismic activity you would expect to find away from the [tectonic] plate boundaries on Earth and away from highly deformed areas,” he said.

Probing the Martian subsurface

InSight touched down near the Martian equator in November 2018, kicking off a two-year, $850 million mission to probe the Red Planet’s interior in unprecedented detail. 

The stationary lander carries two main science instruments to do this work: a supersensitive suite of seismometers and a burrowing heat probe dubbed “the mole,” which is designed to get at least 10 feet (3 meters) below the Red Planet’s surface. 

Analyses of marsquake and heat-transport measurements will allow the mission team to construct a detailed, 3D map of the Martian interior, NASA officials have said. In addition, InSight scientists are using radio signals beamed from the lander to track how much Mars wobbles on its axis over time. This information will help researchers determine how big and dense the planet’s core is. (The mission’s full name — Interior Exploration using Seismic Investigations, Geodesy and Heat Transport — references these various lines of investigation.)

Overall, InSight’s observations will help scientists better understand how rocky planets such as Mars, Earth and Venus form and evolve, mission team members have said.

The mission’s initial science returns, which were published today (Feb. 21) in six papers in the journals Nature Geoscience and Nature Communications, show that InSight is on track to meet that long-term goal, Banerdt said. (We have gotten a taste of these results over the past year or so, however, as mission team members have released some findings in dribs and drabs.)

Related: NASA’s Mars InSight lander: 10 surprising facts

Lots of quakes

The new studies cover the first 10 months of InSight’s tenure on Mars, during which the lander detected 174 seismic events. 

These quakes came in two flavors. One hundred and fifty of them were shallow, small-magnitude tremors whose vibrations propagated through the Martian crust. The other 24 were a bit stronger and deeper, with origins at various locales in the mantle, InSight team members said. (But even those bigger quakes weren’t that powerful; they landed in the magnitude 3 to 4 range. Here on Earth, quakes generally must be at least magnitude 5.5 to damage buildings.)

That was the tremor tally through September 2019. InSight has been busy since then as well; its total quake count now stands at about 450, Banerdt said. And all of this shaking does indeed originate from Mars itself, he added; as far as the team can tell, none of the vibrations were caused by meteorites hitting the Red Planet. So, there’s a lot going on beneath the planet’s surface.

But that activity is quite different from what we’re used to on Earth, where most quakes are caused by tectonic plates sliding against, over or under each other. Mars doesn’t have active plate tectonics, the researchers said, so both types of quakes are caused by the long-term cooling of the planet since its formation 4.5 billion years ago.

“As the planet cools, it contracts, and then the brittle outer layers then have to fracture in order to sort of maintain themselves on the surface,” Banerdt said. “That’s kind of the long-term source of stresses.”

And some Martian locales are more stressed than others. One particularly active region is the Cerberus Fossae fracture system, which lies about 1,000 miles (1,600 kilometers) east of InSight’s Elysium Planitia landing site.

The mission team traced two of the largest detected marsquakes to Cerberus Fossae, which “contains faults, volcanic flows and liquid water outflow channels with ages as recent as 2-10 Ma [million years ago], and possibly younger from impact crater counts,” Banerdt and his colleagues wrote in one of the new studies.

“So, it’s possible that there’s actual magma at depth that’s cooling,” InSight deputy principal investigator Sue Smrekar, also of JPL, said during Thursday’s teleconference. That cooling would lead to the contraction of the magma chamber, causing deformation of the crust, she added.

But Smrekar stressed that this is a hypothesis, not a definitive determination of what’s going on at Cerberus Fossae. Indeed, though mission team members think they understand Martian seismicity in broad strokes, they’re still trying to nail down how it works in detail.

Related: 7 biggest mysteries of Mars

Many insights

A wealth of information can be gleaned from InSight’s quake measurements. For example, analyses of how the seismic waves move through the Martian crust suggest there are small amounts of water mixed in with the rock, mission team members said. 

“Our data is consistent with a crust which has some moisture in it, but we can’t say one way or the other whether there [are] large underground reservoirs of water at this point,” Banerdt said.

The new papers report a variety of other discoveries as well. For example, InSight is the first mission ever to tote a magnetometer to the Martian surface, and that instrument detected a local magnetic field about 10 times stronger than would be expected based on orbital measurements. (Mars lost its global magnetic field billions of years ago, however. This allowed solar particles to strip away the once-thick Martian atmosphere, which spurred the planet’s transition from a relatively warm and wet world to the cold desert it is today.)

InSight is also taking a wealth of weather data, measuring pressure many times per second and temperature once every few seconds, Banerdt said. This information helps the mission team better understand environmental noise that could complicate interpretations of the seismic observations, but it also has considerable stand-alone value.

“This is really going to, I think, revolutionize our understanding of the interaction of the atmosphere with the surface of Mars,” Banerdt said. “That’s one of the things that’s really going to open up a whole new window of research on Mars.”

Mole update

Not everything has gone smoothly for InSight, however. Notably, the mole has been unable to get down to its prescribed depth because the Martian dirt is proving more slippery than mission team members had anticipated. (The mole’s self-hammering burrowing system requires a certain amount of friction to work.)

The mission team has tried several strategies to get the mole moving, including pressing on the side of the probe with InSight’s robotic arm to generate the required friction. This latter tactic has generated some halting success, but the mole remains stranded too close to the surface. 

So, in the next six to eight weeks, mission team members aim to try a modification of the arm-pressing strategy, in which they’ll push on the mole’s back rather than its side. The goal is to get the mole about 16 inches (40 centimeters) down, at which point it will hopefully be able to start digging on its own, Banerdt said.

The InSight team would also like a bit more cooperation from Mars on the seismic side of things, if possible. The lander has not yet spotted any truly big quakes, which have the potential to paint a clearer picture of the planet’s deep interior for mission scientists.

The lack of powerful quakes is no surprise, Banerdt stressed; big tremors are much rarer than their smaller counterparts here on Earth, after all. So, the team may have to wait a while to get one.

But such issues aren’t derailing the mission; the team is excited about how things have gone thus far, Banerdt said.

“I think we’re well on our way to getting most, if not all, of the goals that we set for ourselves 10 years ago when we started this mission,” he said.

Mike Wall is the author of “Out There” (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook

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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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