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Mars InSight Lander Yields a Year of Surprising Discoveries Above

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In this artist’s concept of NASA’s InSight lander on Mars, layers of the planet’s subsurface can be seen below and dust devils can be seen in the background. Credit: IPGP/Nicolas Sarter

A batch of new papers summarizes the lander’s findings.

A new understanding of Mars is beginning to emerge, thanks to the first year of NASA’s InSight lander mission. Findings described in a set of six papers published today reveal a planet alive with quakes, dust devils and strange magnetic pulses.

Five of the papers were published in Nature. An additional paper in Nature Geoscience details the InSight spacecraft’s landing site, a shallow crater nicknamed “Homestead hollow” in a region called Elysium Planitia.

InSight is the first mission dedicated to looking deep beneath the Martian surface. Among its science tools are a seismometer for detecting quakes, sensors for gauging wind and air pressure, a magnetometer, and a heat flow probe designed to take the planet’s temperature.

Cerberus Fossae Mars

The two largest quakes detected by NASA’s InSight appear to have originated in a region of Mars called Cerberus Fossae. Scientists previously spotted signs of tectonic activity here, including landslides. This image was taken by the HiRISE camera on NASA’s Mars Reconnaissance Orbiter. Credit: NASA/JPL-Caltech/University of Arizona

While the team continues to work on getting the probe into the Martian surface as intended, the ultra-sensitive seismometer, called the Seismic Experiment for Interior Structure (SEIS), has enabled scientists to “hear” multiple trembling events from hundreds to thousands of miles away.

Seismic waves are affected by the materials they move through, giving scientists a way to study the composition of the planet’s inner structure. Mars can help the team better understand how all rocky planets, including Earth, first formed.

Underground

Mars trembles more often — but also more mildly — than expected. SEIS has found more than 450 seismic signals to date, the vast majority of which are probably quakes (as opposed to data noise created by environmental factors, like wind). The largest quake was about magnitude 4.0 in size — not quite large enough to travel down below the crust into the planet’s lower mantle and core. Those are “the juiciest parts of the apple” when it comes to studying the planet’s inner structure, said Bruce Banerdt, InSight principal investigator at JPL.

Scientists are ready for more: It took months after InSight’s landing in November 2018 before they recorded the first seismic event. By the end of 2019, SEIS was detecting about two seismic signals a day, suggesting that InSight just happened to touch down at a particularly quiet time. Scientists still have their fingers crossed for “the Big One.”

InSight Lander Studying Seismic Activity

A cutaway view of Mars showing the InSight lander studying seismic activity. Credit: J.T. Keane/Nature Geoscience

Mars doesn’t have tectonic plates like Earth, but it does have volcanically active regions that can cause rumbles. A pair of quakes was strongly linked to one such region, Cerberus Fossae, where scientists see boulders that may have been shaken down cliffsides. Ancient floods there carved channels (see image below) nearly 800 miles (1,300 kilometers) long. Lava flows then seeped into those channels within the past 10 million years — the blink of an eye in geologic time.

Some of these young lava flows show signs of having been fractured by quakes less than 2 million years ago. “It’s just about the youngest tectonic feature on the planet,” said planetary geologist Matt Golombek of JPL. “The fact that we’re seeing evidence of shaking in this region isn’t a surprise, but it’s very cool.”

At the Surface

Billions of years ago, Mars had a magnetic field. It is no longer present, but it left ghosts behind, magnetizing ancient rocks that are now between 200 feet (61 meters) to several miles below ground. InSight is equipped with a magnetometer — the first on the surface of Mars to detect magnetic signals.

The magnetometer has found that the signals at Homestead hollow are 10 times stronger than what was predicted based on data from orbiting spacecraft that study the area. The measurements of these orbiters are averaged over a couple of hundred miles, whereas InSight’s measurements are more local.

Fissure Near Cerberus Fossae

The linearity of the volcanic vent shown in this image observed by NASA Mars Reconnaissance Orbiter, in conjunction with evidence of lava flow from the vent, suggests control by combined volcano-tectonic processes. Credit: NASA/JPL-Caltech/Univ. of Arizona

Because most surface rocks at InSight’s location are too young to have been magnetized by the planet’s former field, “this magnetism must be coming from ancient rocks underground,” said Catherine Johnson, a planetary scientist at the University of British Columbia and the Planetary Science Institute. “We’re combining these data with what we know from seismology and geology to understand the magnetized layers below InSight. How strong or deep would they have to be for us to detect this field?”

In addition, scientists are intrigued by how these signals change over time. The measurements vary by day and night; they also tend to pulse around midnight. Theories are still being formed as to what causes such changes, but one possibility is that they’re related to the solar wind interacting with the Martian atmosphere.

In the Wind

InSight measures wind speed, direction and air pressure nearly continuously, offering more data than previous landed missions. The spacecraft’s weather sensors have detected thousands of passing whirlwinds, which are called dust devils when they pick up grit and become visible. “This site has more whirlwinds than any other place we’ve landed on Mars while carrying weather sensors,” said Aymeric Spiga, an atmospheric scientist at Sorbonne University in Paris.

Despite all that activity and frequent imaging, InSight’s cameras have yet to see dust devils. But SEIS can feel these whirlwinds pulling on the surface like a giant vacuum cleaner. “Whirlwinds are perfect for subsurface seismic exploration,” said Philippe Lognonné of Institut de Physique du Globe de Paris (IPGP), principal investigator of SEIS.

Still to Come: The Core

InSight has two radios: one for regularly sending and receiving data, and a more powerful radio designed to measure the “wobble” of Mars as it spins. This X-band radio, also known as the Rotation and Interior Structure Experiment (RISE), can eventually reveal whether the planet’s core is solid or liquid. A solid core would cause Mars to wobble less than a liquid one would.

This first year of data is just a start. Watching over a full Martian year (two Earth years) will give scientists a much better idea of the size and speed of the planet’s wobble.

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Talk like you: Scientists discover why humans evolved to talk while other primates can’t – Euronews

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Why did humans evolve to talk, while monkeys were left to hoot, squeak and grunt to communicate?

The question has long puzzled scientists, who blamed our closest primate cousins’ inability to reproduce human speech sounds on their vocal anatomy.

Until now, researchers could not quite underpin what happened exactly during our evolution to make us able to speak while apes and monkeys can’t, given our vocal structures look almost identical to other primates.

Now, a new study published on Thursday in the journal Science claims to have the answer – and it’s not what anyone expected.

Analysing the phonal apparatus – the larynx – of 43 species of primates, a team of researchers based mainly in Japan found that all non-human primates – from orangutans to chimpanzees – had an additional feature in their throat that humans do not have.

Ability to speak and develop languages

While both humans and non-human primates produce sounds by forcing air through their larynges, causing folds of tissue to vibrate, monkeys and apes have an additional feature, a thin flap of tissue known as vocal membranes, or vocal lips.

Compared to apes and monkeys, humans were found to lack this anatomical vocal membrane – a small muscle just above the vocal cords – as well as balloon-like laryngeal structures called air sacs which apes and monkeys use to produce the loud calls and screams we’re not quite capable of.

According to the researchers, humans have lost this extra vocal tissue over time, somehow simplifying and stabilising the sounds coming out of our throat, and allowing us, in time, to develop the ability to speak – and eventually develop very complex sophisticated languages.

Monkeys and apes, on the other hand, maintained these vocal lips which don’t really allow them to control the inflection and register of their voice and produce stable, clear vocal fold vibrations.

“Paradoxically, the increased complexity of human spoken language thus followed simplification of our laryngeal anatomy,” says the study.

Communication through sign language

It’s unclear when humans lost these extra tissues still present in apes and monkeys and became able to speak, as the soft tissues in the larynx are not preserved in fossils, and researchers could only study living species.

We know that it must have happened sometime after the Homo Sapiens lineage split from the other primates, some 6-7 million years ago.

The fact that apes and monkeys haven’t developed the ability to speak like humans doesn’t mean that they are not able to clearly communicate with each other.

Though their vocal anatomy doesn’t allow them to form vowel sounds and proper words, non-human primates have a complex communication system based primarily on body language rather than oral sounds.

But monkeys and apes have also proven to be able to communicate with humans.

In the not-often-happy history of the interaction between non-human primates and humans, researchers have been able to teach apes and monkeys to communicate with people.

Koko the gorilla, for example, became famous for being able to use over 1,000 hand signs in sign language, while the bonobo Kanzi was reportedly able to communicate using a keyboard.

But when it comes to having a chat, monkeys and humans might never be able to share one.

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When Summer 'Supermoons' Hit Your Eye: Spectacular Photos – Forbes

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When the moon takes the celestial stage during the summer, the spectacle is simply amazing: Currently topping the program is the Sturgeon Supermoon, shining in all its splendor.

In July, it was the Buck Supermoon, the biggest and shiniest of the year. That one followed the Strawberry Supermoon that delighted sky watchers in June.

They have other stage names. This Sturgeon Moon, which derives its principal name from the giant sturgeon fish season in the Great Lakes, is known also as Thunder Moon, Mead Moon and Hay Moon, among others, and is the last supermoon of the year.

July’s Buck Moon, which drew that name because the antlers of male deer — bucks — are in full-growth mode at the time, is also called Salmon Moon and Berry Moon.

The Strawberry supermoon of June gets its name from fruit harvest seasons. It’s also known as Blooming Moon, Honey Moon and the Mead Moon.

The full moon names collected by the iconic Old Farmer’s Almanac come mainly from Native American tribes, Colonial American, and European sources.

“A full moon doubles as a supermoon when it’s near perigee, or the point in the moon’s orbit that is closest to Earth,” the Almanac explains, making it larger and brighter.

August’s Sturgeon Moon is the fourth and final supermoon of the year and it happens to coincide with the Perseid meteor shower, considered by many as “the best meteor shower of the year,” according to NASA. It will peak on August 13 and will remain active through August 24.

And if you happen to notice a bright-looking “star” near the moon, you’re looking at Saturn.

Lunar lovers and star seekers have been enjoying the summer’s stunning celestial performances and here are some of the best photos taken around the globe:

July’s Buck Supermoon

June’s Strawberry Supermoon of June

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Tips on how to spot the 2022 Perseid meteor shower – StrathmoreNow.com

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The Perseid meteor shower will peak this year early Saturday morning over Cochrane. 

Local photographer, Dylan Kaniski is gearing up for some sleepless nights to ensure the perfect shot. “I’m always really excited for this meteor shower, it is one of the biggest of the year and we always get a lot of great meteors.”

Meteor showers are clouds of debris left when comets zoom past Earth on their way around the sun. The Perseids come from the comet Swift-Tuttle, which was last visible in 1992. While Cochranites won’t be seeing the comet again until 2125, in the meantime, sky gazers can enjoy the yearly shower from the debris. 

“It does change every year and some years are better than others. But this one is special because the Perseids are pretty consistent from year to year. I usually get a really good shot and that’s why people are really excited about this.”

Unfortunately, a full moon will make it trickier to see this year but Kaniski has plenty of tips for people looking to experience the Perseids for the first time.

“The best way to view the meteor shower is to first get somewhere dark. It doesn’t have to be anywhere super far. I personally like going to the mountains but anywhere around Cochrane, you can go to the countryside just 10 minutes out of town.”

“If you can’t make it out of town, just go into a local park or even turning your back to any streetlights and just letting your eyes adjust is going to help out.”

He also believes you don’t need top-of-the-line photography equipment to get breathtaking shots.

“You don’t need any fancy equipment or anything special. Meteors do move quite fast and they’re usually quite bright so you don’t really have any struggles capturing them with any-level cameras.”

“For advice on cameras, I like to do a higher ISO around like 6,400 and usually a 20-second exposure time. If people are heading out and want to capture it with their cameras, I suggest using a focal length that’s a little bit tighter because a lot of meteors can be a bit smaller, and having a tighter focal length will allow you to emphasize the size of the meteor. Something like 20 to 35 millimeters is what I would recommend.”

”I’d stay away from the super wide angle lenses that you see a lot of nighttime and landscape photographers using.”

While the 2022 Perseid meteor shower will peak early on August 13, 2022, meteors could be visible on clear nights leading up to and past Saturday morning.

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