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Despite Concerns, Space Junk Continues to Clutter Earth Orbit

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a cloud of many particles surrounds Earth

Earth orbit is getting cluttered. (Credit: NASA)

Humans have a tendency to litter wherever we go. Whether it’s the local park, a music festival, or Mt. Everest, we’re just not good at cleaning up after ourselves. And space is no exception.

Space is pretty big. Infinite, in fact. But the same can’t be said of low-Earth orbit (LEO) and, in particular, the most popular orbital lanes used by Earth-sensing and communications satellites. We’re launching more objects skyward every year and not, in many cases, cleaning up when we’re done with them. So the space around us is starting to fill up. 

Messy Space

a tiny metal sphere inside a large impact crater

Even tiny objects can cause serious damage at orbital speeds. (Credit: ESA)

Even when Sputnik launched in 1957, it wasn’t alone. The shiny ball was accompanied by its core stage and payload fairing, both of which tumbled around Earth in nearby orbits. Much of the hardware we launch is similarly partnered, meaning each launch can be responsible for multiple pieces of orbital debris. Much of this “debris” is, of course, composed of hard-working satellites performing valuable jobs. But the majority is derelict, either drifting past its useful lifetime or genuine trash like the spent rocket stages. And “drifting” is a relative term here: Some objects in orbit are moving at up to 17,000 miles per hour.

As human technology needs have become greater, we’ve also become more reliant on growing numbers of satellites. Newly proposed “constellations” of dozens or even thousands of satellites could greatly expand the number of artificial companions in orbit around us —communications networks more or less require them in order to deliver global coverage. The well-established Iridium satellite phone network uses 66 satellites (plus a few spares if something goes wrong — more on that below). SpaceX recently received FCC approval to launch roughly 12,000 satellites for their planned space-based internet.

Many of the new generation of satellites could by tiny, but numerous. CubeSats are tiny satellites much touted as gateways for even small research groups or companies to gain access to space science, thanks to the low cost of launch and development. But that very ease of access means they’re flooding the skies in greater numbers every year.

The more cluttered space becomes, the greater risk there is for a collision. And this is no hypothetical. In fact, a large fraction of the debris we know about in space is the result of just two past collisions. The first, in 2007, was China’s intentional “destruction” of a weather satellite as a test of their ability to destroy objects in space. The problem is that while they very successfully demolished the satellite (one China also owned, by the way), what they also did was turn it from one orbiting object into a few thousand, many of which are still circling us today. These drifting bits of debris are a lot harder to track than one derelict weather satellite. This alone angered other space agencies, not to even mention the thorny issue of militarizing space.

The second noteworthy event happened in 2009, when an active Iridium satellite crashed into a deactivated Russian communications satellite. The resulting accident created a debris cloud similar to the one from the intentional destruction of the Chinese satellite two years earlier, but much more frightening. After all, you can at least try to tell the Chinese government to knock it off, but you can’t stop Newton’s laws of motion once the satellites are already up there.

Orbital Dodgeball

So, to recap: There are working spacecraft, derelict satellites, discarded remnants of past launches and repair jobs and a few thousand pieces of barely trackable former satellites whirling around the Earth at velocities high enough to make even a grain of sand a killer. There are also a few million pieces smaller than golf ball-sized that we can’t track, but which could still punch a hole in a lot of delicate equipment. Some burn up in the atmosphere, but most will be up there for the foreseeable future.

So what are we doing about all this dangerous orbiting debris?

We’re monitoring the situation, to start. NASA and other agencies are doing their best to keep track of where this orbital debris is, down to the smallest pieces they can track. But it’s an inexact science, and smaller objects, or those tumbling haphazardly, can only be tracked approximately. Objects in LEO pass within a few kilometers of each other every single day. When they’re on tighter trajectories, the satellite operators can usually adjust their course, but this relies on at least one of the objects still being under human control. If both pieces are out of fuel or otherwise not maneuverable, there’s little operators can do.

For astronauts in the International Space Station, protocol is for them to hunker down in the Soyuz capsule if a collision or near-miss is expected, much as they do for any dangerous situation. (A recent hole discovered in said capsule — which may have come from an orbital collision — reveals even that strategy has its dangers, though.)

Cleaning Up Our Act

a cubic satellite in space

RemoveDEBRIS is a satellite designed to test various ways of cleaning up orbital clutter. (Credit: NASA)

Space agencies and private companies are under more and more pressure to clean up after themselves. This means making sure to de-orbit their satellites and accompanying space trash, either by driving them low to burn up in Earth’s atmosphere or flying away to higher, less-crowded orbits. But there aren’t any space police to make people follow the rules, meaning enforcement of these policies is no guarantee.

How to De-Clutter Space

Instead of preventing new debris, a group of researchers at the University of Surrey are trying to deal with the trash that already exists. This past September, they tested out a satellite called RemoveDEBRIS. The small craft threw out a net in orbit, grabbed a hunk of test trash, and set it on a new course to burn up as harmless wreckage in Earth’s atmosphere. (Most plans end with burning up debris in Earth’s atmosphere. While it sounds dangerous, the odds of any piece making it through to damage Earth’s surface are staggeringly low.) It will also test harpooning objects to collect them, and using cameras to navigate and report on nearby debris.

To avoid being called a hypocrite, at the end of its life RemoveDEBRIS will deploy a sail to drag itself into Earth’s atmosphere and burn up.

Scientists at Tohoku University in Japan are working on a different solution. This one involves ion-beam shepherding, a sort of anti-tractor beam concept that hasn’t been tested in real life yet, but is plausible with current technology. The idea would let a satellite push orbiting debris into Earth’s atmosphere, a more renewable plan than throwing nets at trash.

Whatever the solution, humans should start figuring it out quickly, because we don’t seem likely to stop launching hardware skyward anytime soon.

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Ecology

Globe Climate: Canada’s resource reckoning is coming

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Good afternoon, and welcome to Globe Climate, a newsletter about climate change, environment and resources in Canada.

This afternoon, the Alberta government announced that it is restoring a coal mining policy it revoked last spring. At the time, the move provoked a widespread public backlash detailed by The Globe. The original decision, which opened up more than 1.4 million hectares to exploration, was made without public consultation. Premier Jason Kenney previously defended the changes.

Lots more on coal and Canada’s resources industry in this week’s newsletter edition.

Now, let’s catch you up on other news.

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Ecology

‘Incredibly destructive’: Canada’s Prairies to see devastating impact of climate change

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As the climate continues to warm at an alarming rate, experts warn if dramatic steps to mitigate global warming are not taken, the effects in Canada’s Prairie region will be devastating to the country’s agriculture sector.

According to Environment and Climate Change Canada, the country is warming, on average, about double the global rate.

Scientists with the National Oceanic and Atmospheric Administration in the U.S. recently found 2020 was earth’s second-hottest year on record, with the average land and ocean surface temperature across the globe at 0.98 of a degree C above the 20th-century average.

However, the agency found the northern hemisphere saw its hottest year on record, at 1.28 degrees C above the average.

“(In Canada) we are looking at about 6.4C degrees of warming this century, which isn’t much less than one degree per decade, which is just a terrifying rate of warming,” Darrin Qualman, the director of climate crisis policy and action at the National Farmer’s Union said.

Qualman said there is “massive change coming” to Canada’s Prairies, which will be “incredibly destructive.”

“It’s not going too far to say that if we made that happen, parts of the Prairies wouldn’t be farmable anymore,” he said.

According to the federal government, in 2018 Canada’s agriculture and agri-food system generated $143 billion, accounting for 7.4 per cent of the country’s GDP.

The sector employed 2.3 million people in 2018. The majority of the 64.2 million hectares of farmland in Canada is concentrated in the Prairies and in southern Ontario.

The effects of climate change are already being felt on the ground in the Prairies, Qualman said, adding that the NFU has already heard from farmers complaining of “challenging weather.”

“People are sharing pictures of flattened crops and buildings, et cetera, that have been damaged,” he said. “And we’re still at the beginning of this.”

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Ecology

Insect-based dog food aims to cut your pet’s carbon pawprint

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Meat has an enormous carbon footprint, with livestock liable for about 15 per cent of worldwide emissions, as we have beforehand mentioned on this e-newsletter. That is prompted specialists to suggest consuming much less meat for sustainability (and well being) causes.

However what about your pet? One research discovered that the methane and nitrous oxide emissions generated by canine and cat meals within the U.S. alone had been equal to about 64 million tonnes of CO2, or roughly the quantity produced by 13.6 million automobiles. And it might be getting worse, with a development towards feeding pets “human-grade” meat.

That is prompted some pet meals makers to look to lower-carbon protein sources — together with bugs.

Research present that producing insect-based meals requires far much less feed, land and water and generates far fewer greenhouse fuel emissions per kilogram than meats comparable to beef, pork or rooster.

That is one of many causes increasingly more pet meals containing insect protein are hitting the market. Purina, a model owned by multinational Nestlé, launched a line of canine and cat meals containing black soldier fly larvae in Switzerland in November.

In Canada, Montreal-based Wilder Harrier began promoting canine treats made with cricket protein in 2015 and pet food made with black soldier fly larvae in 2019. It plans to broaden to launch a line of insect-based cat treats later this yr and cat meals in 2022 due to “a ton of demand,” mentioned firm co-founder Philippe Poirier.

Wilder Harrier initially labored with animal nutritionists on insect-based merchandise to unravel a unique downside — specifically, the founders’ canines had allergy symptoms to frequent meats utilized in canine meals. Poirier mentioned now about half its prospects hunt down the product due to their pets’ allergy symptoms and about half for environmental causes.

Dr. Cailin Heinze, a U.S.-based veterinary nutritionist licensed by the American School of Veterinary Vitamin, has written concerning the environmental influence of pet meals. She mentioned we’re typically “not as involved as we probably ought to [be]” concerning the environmental footprint of pets.

Alternatively, she famous that the longer-term influence of newer diets, comparable to vegan meals and people containing bugs, hasn’t been nicely examined in comparison with conventional pet meals.

Maria Cattai de Godoy, an assistant professor of animal sciences on the College of Illinois who research novel proteins for pet meals (together with bugs, yeast and plant-based substances), mentioned such substances are rigorously examined to find out their security and diet earlier than being added to pet meals. 

“This can be a very extremely regulated trade,” she mentioned, however admitted it is also evolving.

Relating to bugs, she mentioned constructive information “reveals promise in direction of utilizing them increasingly more in pet meals.” Insect-based proteins have additionally earned the endorsement of the British Veterinary Affiliation, which says some insect-based meals could also be higher for pets than prime steak.

However Godoy famous that there isn’t any one-size-fits-all resolution, and pet homeowners ought to take into consideration the wants of their very own particular person pet and analysis whether or not a specific weight loss plan can be appropriate.

She mentioned that other than the kind of protein, issues like packaging and manufacturing strategies may also make a distinction. For instance, utilizing meat byproducts that may in any other case turn into waste would not drive elevated meat manufacturing the identical approach as utilizing human-grade meat.

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