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My time at iREx – James Sikora | Institute for Research on Exoplanets – News | Institute for Research on Exoplanets

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James Sikora. Photo provided by James .

James Sikora, a postdoctoral fellow at Bishop’s University, joined the iREx in September 2019. In September 2022, he left iREx to pursue his career as a postdoc at the Anton Pannekoek Institute for Astronomy at the University of Amsterdam where he’ll be continuing to do exoplanet research. He answered a few of our questions about his time at iREx.

What did you like most about your time in Montreal?

As a member of the exoplanet group at Bishop’s University, I spent most of my time in Lennoxville, Sherbrooke. Aside from the wonderful people that I’ve been fortunate to meet and work with during this time, I also enjoyed being close to beautiful lakes and mountainous landscapes. The fall season in the Eastern Townships of Quebec is truly special!

What were the most important projects you led at iREx?

I think the most important and exciting projects I have been leading while a member of iREx have been (1) an upcoming James Webb Space Telescope observing program targeting an unusual hot Jupiter-like planet and (2) a program using the Gemini-North telescope in Hawai’i to collect high-precision radial velocity measurements in order to study a system of very young planets.

Field guide for hot Jupiters: Orange-banded Jupiter-like planet near a blazing, roiling sun.

An artistic rendition of a really hot Jupiter-like exoplanet similar to the one that will be studied by James and his collaborators. Credit : ATG MEDIALAB, ESA.

What question were you trying to answer in these projects?

In the case of the Webb Telescope observations that are scheduled for November of 2022, we are hoping to help answer questions about the conditions under which clouds form and dissipate within the atmospheres of hot Jupiter-like planets. We will do this by observing a particularly special planet that has a highly eccentric orbit. The distance between the planet and its host star — and hence, the amount of energy absorbed by the planet and its atmosphere — varies dramatically over the course of a single orbit.

Obtaining high-precision radial velocity measurements can allow you to measure an exoplanet’s mass. The vast majority of exoplanets discovered to date are old (i.e., either close in age to the Solar System planets or older). Measuring the masses of very young planets — such as those that we have recently observed using Gemini — can give us important clues about how planets form and evolve. When and to what extent do gas-rich planets shed their outer layers? How quickly do gas-rich planets contract as they cool over time?

What did you discover?

While the Webb Telescope observations have yet to be obtained, recent publicly released data from the telescope has shown that the instruments are performing spectacularly, making us all very excited for our own upcoming observations.

For the high-precision radial velocity measurements of young planets, our preliminary results are in agreement with the current theoretical understanding of how gas-rich planets cool and contract over timescales of hundreds of millions to billions of years. This kind of confirmation provides a key constraint that can be used in models to improve our understanding of planetary formation both outside and within our own Solar System. We are working on a paper that will give more details on this subject. Stay tuned for the full story!

What motivates you in exoplanet research?

What motivates me to do exoplanet research is largely the end product: learning something new that helps to push the boundaries of what we currently know about planetary formation and evolution. However, I am motivated by the whole process of doing observational astronomy; I feel extremely privileged to be able to use amazing, cutting-edge observatories to collect previously unseen measurements that ultimately lead to new discoveries.

Why do you think people should be interested in this kind of work?

I believe that any research that can help us better understand how we as the human species got to where we are today and where we might be headed hundreds or thousands of years from now to be very important and exciting. The diverse landscape of exoplanets discovered so far provides us with important clues that help to guide our fundamental understanding of how planets such as those found in the Solar System form and evolve.

How does your time with us helped you in your new job?

While spending time within iREx, I learned a ton about new and improved methods of analysing observational data sets. Moreover, thanks to help from researchers at iREx and Bishop’s University, I’ve been able to get my hands on a wide range of data that I did not previously have a lot of experience with such as high-precision transit spectroscopy and radial velocity measurements. This has allowed me to greatly expand my skillset in the context of observational exoplanet research, which is already helping me to develop new and exciting paths for my own research moving forward.

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Giant prehistoric salmon had tusk-like teeth for defence, building nests

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The artwork and publicity materials showcasing a giant salmon that lived five million years ago were ready to go to promote a new exhibit, when the discovery of two fossilized skulls immediately changed what researchers knew about the fish.

Initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and had led researchers to mistakenly suggest the fish had fang-like teeth.

It was dubbed the “sabre-toothed salmon” and became a kind of mascot for the Museum of Natural and Cultural History at the University of Oregon, says researcher Edward Davis.

But then came discovery of two skulls in 2014.

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Davis, a member of the team that found the skulls, says it wasn’t until they got back to the lab that he realized the significance of the discovery that has led to the renaming of the fish in a new, peer-reviewed study.

“There were these two skulls staring at me with sideways teeth,” says Davis, an associate professor in the department of earth sciences at the university.

In that position, the tusk-like teeth could not have been used for biting, he says.

“That was definitely a surprising moment,” says Davis, who serves as director of the Condon Fossil Collection at the university’s Museum of Natural and Cultural History.

“I realized that all of the artwork and all of the publicity materials and bumper stickers and buttons and T-shirts we had just made two months prior, for the new exhibit, were all out of date,” he says with a laugh.

Davis is co-author of the new study in the journal PLOS One, which renames the giant fish the “spike-toothed salmon.”

It says the salmon used the tusk-like spikes for building nests to spawn, and as defence mechanisms against predators and other salmon.

The salmon lived about five million years ago at a time when Earth was transitioning from warmer to relatively cooler conditions, Davis says.

It’s hard to know exactly why the relatives of today’s sockeye went extinct, but Davis says the cooler conditions would have affected the productivity of the Pacific Ocean and the amount of rain feeding rivers that served as their spawning areas.

Another co-author, Brian Sidlauskas, says a fish the size of the spike-toothed salmon must have been targeted by predators such as killer whales or sharks.

“I like to think … it’s almost like a sledgehammer, these salmon swinging their head back and forth in order to fend off things that might want to feast on them,” he says.

Sidlauskas says analysis by the lead author of the paper, Kerin Claeson, found both male and female salmon had the “multi-functional” spike-tooth feature.

“That’s part of our reason for hypothesizing that this tooth is multi-functional … It could easily be for digging out nests,” he says.

“Think about how big the (nest) would have to be for an animal of this size, and then carving it out in what’s probably pretty shallow water; and so having an extra digging tool attached to your head could be really useful.”

Sidlauskas says the giant salmon help researchers understand the boundaries of what’s possible with the evolution of salmon, but they also capture the human imagination and a sense of wonder about what’s possible on Earth.

“I think it helps us value a little more what we do still have, or I hope that it does. That animal is no longer with us, but it is a product of the same biosphere that sustains us.”

This report by The Canadian Press was first published April 24, 2024.

Brenna Owen, The Canadian Press

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Giant prehistoric salmon had tusk-like spikes used for defence, building nests: study

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A new paper says a giant salmon that lived five million years ago in the coastal waters of the Pacific Northwest used tusk-like spikes as defense mechanisms and for building nests to spawn.

The initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and led researchers to suggest the fish had fang-like teeth.

The now-extinct fish was dubbed the “saber-tooth salmon,” but the study published in the peer-reviewed journal PLOS One today renames it the “spike-toothed salmon” and says both males and females possessed the “multifunctional” feature.

Study co-author Edward Davis says the revelation about the tusk-like teeth came after the discovery of fossilized skulls at a site in Oregon in 2014.

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Davis, an associate professor in the department of earth sciences at the University of Oregon, says he was surprised to see the skulls had “sideways teeth.”

Contrary to the belief since the 1970s, he says the teeth couldn’t have been used for any kind of biting.

“That was definitely a surprising moment,” Davis says of the fossil discovery in 2014. “I realized that all of the artwork and all of the publicity materials … we had just made two months prior, for the new exhibit, were all out of date.”

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SpaceX sends 23 Starlink satellites into low-Earth orbit

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April 23 (UPI) — SpaceX launched 23 Starlink satellites into low-Earth orbit Tuesday evening from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.

Liftoff occurred at 6:17 EDT with a SpaceX Falcon 9 rocket sending the payload of 23 Starlink satellites into orbit.

The Falcon 9 rocket’s first-stage booster landed on an autonomous drone ship in the Atlantic Ocean after separating from the rocket’s second stage and its payload.

The entire mission was scheduled to take about an hour and 5 minutes to complete from launch to satellite deployment.

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The mission was the ninth flight for the first-stage booster that previously completed five Starlink satellite-deployment missions and three other missions.

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