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A Radioactive Metal May Be Vital For Building Water Worlds




water world exoplanet formation

Planets that form in regions with high levels of aluminum may be left with dry materials leading to Earth-like planets, while those in aluminum-light environments may stay wet and form ocean worlds. (Credit: Roger Thibaut)

While we tend to think that Earth’s oceans make it a watery planet, it’s actually only a tiny fraction of a percent of water by mass. Looking out into the universe, it’s clear water is more common than our own planet implies. Some exoplanets can have half their mass as water. So, what causes some planetary systems to stay wet, while others dry out? The answer might be aluminum.

Tim Lichtenberg is the lead author of a new study published Feb. 11, in Nature Astronomy. He says that large amounts of Al-26, a radioactive form of aluminum, can heat up and dry out the large boulders, some 5 to 50 miles across (called planetesimals), that collide to form planets. As a result, the amount of aluminum a young system has could be a predictor of what types of planets will evolve there.

Location and Size Matter

All stars tend to heat and dry out material – from pebbles to planetesimal – that orbits closer than what’s called the snow line. Beyond the snow line, ice sticks around and gets incorporated into planets, which can then keep that ice and eventually turn it into water, even if they later migrate closer to the sun. For instance, our own Earth keeps water trapped under its atmosphere, while Mars, farther out, lost its water. Both are now inside the snow line, but probably formed farther out.

Aluminum heating only matters to planetesimals of a certain size. Small pebbles don’t have enough Al-26 to cause any heating. Full-size planets may be able to hang onto their water through other methods – like having an atmosphere. But aluminum heating would affect all planetesimals in the unlucky size range, no matter how close or far they are from their sun.

Missing Water

A good example of this effect in action might be the TRAPPIST-1 exoplanet system. TRAPPIST-1 has seven rocky planets circling a dim red dwarf star. Three are in the habitable zone, and all are thought to be temperate enough to host water. Researchers still don’t know all the details of the system, and Lichtenberg cautions that uncertainties are still high for many of the TRAPPIST-1 planets. But it seems that only about one percent of their mass is made of water, which is surprising to most planetary scientists. Red dwarfs are cool stars compared to the sun, meaning their snow line should be quite close, allowing lots of icy material for planets to sop up as water. So if this water is missing, it’s worth asking why.

TRAPPIST-1 is strange in another way. In any system, planets circling farther from the star, traveling larger orbits, should have more chances to pick up icy material – they literally travel a bigger circuit through space. But that’s not what observers see in the TRAPPIST-1 system. Lichtenberg says, “This speaks to a system-wide mechanism, which is exactly what our Al-26 method is.”

Lichtenberg points out there’s no proof that aluminum heating caused our solar system or TRAPPIST-1’s relative dryness. “This is not the only method,” he says, that can dry out systems. “But it is a powerful one.”


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Yukon and Northern BC First Nations tackle climate change using Indigenous knowledge and science




YUKON, June 18, 2021 /CNW/ – The Government of Canada is working together in partnership with Indigenous and Northern communities in finding solutions to adapt to the impacts of climate change in the North.

Today, Minister of Northern Affairs, Daniel Vandal, along with Parliamentary Secretary to the Minister of Economic Development and Official Languages (Canadian Northern Economic Development Agency), Larry Bagnell, highlighted progress on three unique, Indigenous-led projects that are helping communities in Yukon and Northern British Columbia adapt to the challenges posed by climate change.

The Minister and Parliamentary Secretary met virtually with Carcross/Tagish First Nation (C/TFN) to learn about their community-led climate change monitoring program. C/TFN has partnered with Tsay Keh Dene Nation (TKDN) and Chu Cho Environmental of Prince George, British Columbia, to build a community-led monitoring project that examines environmental data and Indigenous knowledge to create a holistic picture of how the climate is changing across C/TFN and TKDN traditional territories. The project combines tracking of current and historical climate trends with knowledge shared by Elders while also providing opportunities for youth mentorship and climate change awareness.

The Taku River Tlingit First Nation (TRTFN) is also leading a unique project to assess the impacts of climate change within their traditional territory. Climate change is causing many of the culturally significant ice patches to melt, exposing organic artifacts to oxygen and leading to rapid deterioration. The TRTFN ice patch mapping project will involve performing archaeological assessments to prevent the degradation of artifacts. Research will be guided by traditional knowledge, Elders and oral histories, when available, and heavily involve community, Elders, youth and Knowledge Keepers.

The Pelly Crossing Selkirk Development Corporation is leading the Selkirk Wind Resource Assessment project through the installation of a Sonic Detection and Ranging (SODAR) system. The initiative includes a feasibility study leading up to the construction of a renewable energy facility, including wind, solar and battery energy storage. Expanding clean energy within the region will have direct benefits for communities, including reduced reliance on diesel, job creation and revenue generation for Selkirk First Nation. 

These projects are delivering important environmental, social and economic benefits that lead to healthier, more sustainable and resilient communities across Yukon and Northern British Columbia. They also build community clean energy capacity and help to avoid the impacts of climate change.

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Atlantic Provinces Ready For Aquaculture Growth




Aquaculture is an important economic driver for rural, coastal and Indigenous communities, and Atlantic Canada is well positioned to increase aquaculture production as global demand for sustainably sourced seafood grows.

That is why the ministers responsible for aquaculture in the Atlantic provinces have agreed to the ongoing development and management of their industries based on common principles. A new memorandum of understanding has been signed by the four ministers, which extends the previous agreement signed in 2008.

“In a time when food security is especially important, it is good to see our aquaculture industry has grown steadily and is poised for continued growth in 2021 based on environmentally responsible, science-based policies and practices,” said Keith Colwell, Minister of Fisheries and Aquaculture for Nova Scotia. “Our Atlantic partnership continues to help the industry grow sustainably.”

Cooperation between the provinces and the aquaculture industry has led to improvements in pest management, environmentally sustainable aquaculture methods, aquatic animal health and policies to support the shared use of marine and freshwater resources. It also aims to align regulation and policy between the provinces to make the regulatory requirements easier to understand by industry and the public.

Each province has a comprehensive and robust legislative and regulatory framework to ensure environmental sustainability, economic prosperity and public accountability. The provinces update their legislation and regulations regularly. Nova Scotia revamped its regulatory framework in 2015; New Brunswick received Royal Assent for a new Aquaculture Act in 2019 and is working on the supporting regulations; Newfoundland and Labrador completely revised its aquaculture policy in 2019; and Prince Edward Island has recently drafted a new Aquaculture Act.

The ministers have agreed to continue to use science-based evidence for management decisions, thereby increasing public and investor confidence in the Atlantic Canadian aquaculture industry.

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COMING SOON: A Healthy Environment and a Healthy Economy 2.0




We all want the same thing: a clean and responsible energy future for our children and future generations while continuing to enjoy a high standard of living.

On December 11, 2020, the Prime Minister announced a new climate plan which he claimed will help achieve Canada’s economic and environmental goals.

The proposed plan by Environment and Climate Change Canada (ECCC) entitled “A Healthy Environment and a Healthy Economy” will have an initial investment of $15 billion of taxpayer’s money. It is built on 5 pillars of action:

  1) Making the Places Canadians Live and Gather More Affordable by Cutting Energy Waste

2) Making Clean, Affordable Transportation and Power Available in Every Community

3) Continuing to Ensure Pollution isn’t Free and Households Get More Money Back

4) Building Canada’s Clean Industrial Advantage

5) Embracing the Power of Nature to Support Healthier Families and More Resilient Communities  

In my paper, “A Healthy Environment and a Healthy Economy 2.0” I will objectively critique each pillar in the government’s new climate plan and provide alternative solutions to the same issues.

  This is an alternative plan that supports workers, protects lower income earners and creates economic growth while respecting the environment and focusing on the dignity of work.

  This plan abandons virtue-signaling projects and relies on Canadian ingenuity to build our economy and restore Canada’s role of responsible leadership in the world.

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