Connect with us


We’ll Need A Whole New Landing Approach to Put Humans On Mars




a spacecraft firing thrusters

A heavy spacecraft would need rockets for braking and steering, but could also be flown to steer itself through lift. (Credit: NASA)

As humans get more ambitious with their plans for exploring Mars, we’re going to need to land bigger spacecraft on its surface. Up until now, NASA’s robotic missions have used parachutes, inflatable bubbles, and sky cranes, as well as descent rockets. But to land the kind of heavy spaceships that can carry human astronauts to Mars, engineers will need new methods to touch down.

At the moment, most spacecraft rely on parachutes to slow down from a whopping Mach 30 or so as they enter the Martian atmosphere. And once those landers are traveling at a more reasonable speed of a few times the speed of sound, engineers have a variety of options to touch down softly.

But those parachutes just aren’t effective for larger craft — they don’t scale well. That prompted aerospace engineers Christopher Lorenz and Zach Putnam to explore other options in a recent paper, published Dec. 31, 2018 in the Journal of Spacecraft and Rockets.

We’re Gonna Need a Bigger Spacecraft

The heaviest craft that’s reached Mars’ surface is the Mars Curiosity rover, at about 2,200 pounds, or just over 1 ton. But crewed spacecraft will likely be much heavier, between five and 20 tons.

That will require using retrorockets to slow the spacecraft, like the ones SpaceX and Blue Origin fire to land their boosters. But this burns a lot of fuel – fuel that must be lifted off Earth (requiring even more fuel). And it takes up cargo space that could otherwise hold human explorers or valuable equipment and supplies.

Fuel for landing maneuvers is therefore at a premium, and mission planners must judge carefully how they spend that fuel, while still making sure to land their spacecraft in a safe location and at a safe speed.

“Once the descent engines are ignited,” Putnam said in a press release, “the engines have a certain amount of propellant. You can fire engines in such a way that you land very accurately, you can forget about accuracy and use it all to land the largest spacecraft possible, or you can find a balance in between.”

You can also steer the vehicle while it’s still moving hypersonically. The Space Shuttle was notorious for being a “flying brick,” but it could be steered. By angling or unbalancing any spacecraft already in motion, engineers can create lift that steers their craft in a given direction – even in Mars’ relatively thin atmosphere.

(As a reminder, a plane doesn’t have to use its engines to turn. If the plane lowers one wing, the entire craft will turn in that direction due to lift.)

This means that mission planners can steer their spacecraft before firing the braking thrusters and burning valuable fuel. They can conserve fuel by carefully choosing both the altitude and angle of the spacecraft for when they do fire the rockets. This lets them fly closer to their intended landing target without burning fuel for steering, while also minimizing the amount of fuel needed to slow the craft.

After considering multiple scenarios, the authors concluded that the most efficient flight path (i.e., the one that burns the least fuel) is to dive nearly straight into the atmosphere at first. The vehicle can then lift up, flying at low altitude where the atmosphere is thickest and produces the most drag on the craft. By using simple physics to slow the craft, mission planners can use less fuel, and therefore pack more science into their future heavy missions.


Source link

قالب وردپرس


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.

Continue Reading


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.

Continue Reading


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.

Continue Reading