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My Thesis in 400 Words: Anne Boucher | Institute for Research on Exoplanets – News | Institute for Research on Exoplanets

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Anne Boucher, an iREx student at the Université de Montréal, submitted her doctoral thesis at the end of 2021. She summarises the research project she carried out as part of her Ph.D here.

During my Ph.D, I became interested in the atmosphere of gas giant exoplanets that orbit very close to their star. Thanks to a technique called transmission spectroscopy, I studied the chemical composition of their atmosphere, which gives a lot of information on their formation and evolution mechanisms. The detailed study of these exoplanets, which we sometimes call hot Jupiters or hot sub-Saturns, provides a better understanding of the physical, chemical, and dynamical processes that govern the atmosphere of these celestial objects.

I mainly used data from the SPIRou instrument, a high-resolution spectropolarimeter that operates in the near infrared and is installed at the Canada-France-Hawaii Telescope. We first observed HD 189733 b, one of the most studied exoplanets, to build the analysis codes. By exploiting transit spectroscopy, we were able to confirm the presence of water and determine its abundance. The results obtained, consistent with previous studies, indicate that the atmosphere of HD 189733 b is relatively clear (free of clouds) and that the planet likely formed far from its star, where it is cold enough to find water in the form of ice. A strong blueshift of water absorption was observed, which could be a consequence of the presence of strong winds in the atmosphere.

Artistic representation of the exoplanet HD 189733 b, credit :  NASA, ESA, and G. Bacon (STScI)

Next, we studied WASP-127 b, a less massive exoplanet, but much larger than Saturn. A recent study of data from the Hubble Space Telescope (HST) and the Spitzer Space Telescope could not differentiate between two atmospheric scenarios: a low carbon-to-oxygen (C/O) ratio with little carbon monoxide (CO), or a high ratio with a lot of CO. As this ratio helps to determine how a planet was formed, we decided to use SPIRou, which makes it possible to observe a band of CO not observable with HST and Spitzer. We were able to determine that there was very little CO and a very low C/O, which has rarely been observed, but which is supported by some more realistic training scenarios that vary over time. The SPIRou data also confirmed the presence of water and suggests that, if confirmed, there could even be hydroxyl (OH): an unexpected detection since the exoplanet is so cold.

This work has allowed to develop the expertise of the Université de Montréal in high resolution near-infrared transit spectroscopy, in particular with SPIRou, allowing to explore the atmospheric conditions of hot Jupiters and sub-Saturns. This first joint analysis made on high and low resolution transmission data allowed to obtain better constraints on the atmospheric parameters. This method is proving to be a very powerful tool for the study of atmospheres and will be even more so with the revolutionary capabilities of JWST.

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Anne worked on her Ph.D. at the Université de Montréal between 2016 and 2022, under the supervision of David Lafrenière. Her thesis will soon be available.

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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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