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Polyethylene furanoate is coming! Don't be scared. – Office for Science and Society

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If you are scared of chemical terminology, you may think you are in for a bumpy ride. But fear not, you do not need a degree in chemistry to follow this discussion. Buckle up, and let’s go. 

Granted, the term “polyethylene furanoate (PEF)” doesn’t exactly roll off the tongue. But bottles and packaging materials made from this plastic may soon be rolling off assembly lines. Why? Because it is recyclable, and more importantly, it can be made from bio-waste such as wheat straw instead of from petroleum. The hope is that it can, at least to some extent, replace polyethylene terephthalate (PET), the petroleum-derived plastic that is used to produce some 600 billion bottles every year. As a bonus, a “cradle-to-grave analysis” shows that compared with the production of PET, PEF is associated with reduced greenhouse gas emissions. 

While life today without plastics is unimaginable, their once common description as “miracle materials” needs an asterisk. Most plastics are made from non-renewable petroleum, and their improper disposal has become an environmental calamity. Views of beaches with washed-up plastic waste, turtles snared in discarded fishing nets, and the giant plastic “garbage patch” in the middle of the Pacific Ocean is very disturbing. So is the knowledge that in the environment, plastics can degrade into “microplastics” that can end up in our food supply, and therefore in us. Ditto for some additives such as phthalate plasticizers and plastic components such as bisphenol A (BPA), which has raised various health concerns. The plastics industry, aware of these problems and the associated adverse publicity, is taking steps to address these issues. But there are many challenges. 

Let’s start by doing an autopsy of a PET bottle, identifiable by the number 1 in the triangular recycling logo. This plastic is made of a polymer of alternating units of ethylene glycol and terephthalic acid linked in a long chain. Ethylene glycol is made from ethylene oxide, which in turn is made by the “catalytic cracking” of petroleum. The precursor of terephthalic acid is para-xylene which is distilled from petroleum. Both processes require the input of energy that comes from burning fossil fuels. One way to “green up” PET production is to derive the ethylene glycol from a renewable resource, namely bioethanol from the fermentation of sugar. This is the technology that allowed Coca-Cola to come up with its much-hyped “plant bottle.” Actually, PET is only 30% ethylene glycol by weight, and its production from bioethanol involves a lot of chemical manipulation. The ethanol is first converted into ethylene, then into ethylene oxide, and then into ethylene glycol. There is a significant environmental footprint here. And of course, the terephthalic acid that makes up 70% of the plastic comes from petroleum.   

That raises the question of finding an alternative to terephthalic acid that does not come from petroleum. And researchers have come up with one! Furan dicarboxylic acid reacts with ethylene glycol just like terephthalic acid does and produces polyethylene furanoate (PEF), a plastic that can be recycled, allows less carbon dioxide and oxygen to pass through than PET, and has higher resistance to mechanical strain which means that bottles and packaging materials can be made thinner. Most importantly, furan dicarboxylic acid be made from plant material such as wheat straw or wood waste through a sequence of reactions made possible by proprietary metal catalysts. There is, however, one big drawback. Cost! Currently, it costs roughly eight times as much to produce PEF than PET. That gap will be reduced as the manufacture of PEF is scaled up. 

There is yet another issue that needs attention. As mentioned, the ethylene needed to make ethylene glycol can be produced from bioethanol rather than from petroleum, which is a step in the right direction. But regardless of the source, the ethylene has to be converted into ethylene oxide which is then used to produce ethylene glycol. The issue is that ethylene oxide is a reproductive toxin, is mutagenic and carcinogenic. Indeed, there are concerns that the increased cancer rates seen around some chemical plants are due to the release of ethylene oxide into the air. Furthermore, the production of ethylene oxide releases large amounts of carbon dioxide.  

So, can ethylene glycol be made without going through ethylene oxide as an intermediate? Not only can that be done, but the starting material can be biomass. Through a sequence of reactions, with the aid of tungsten-based catalysts, plant material can be converted into glycolaldehyde which in turn can be hydrogenated to yield ethylene glycol. The whole process releases less carbon dioxide than the production of ethylene oxide. Is there a fly in the ointment? So far, the synthesis of ethylene glycol by this process is only at the pilot plant stage and it remains to be seen whether it can prove to be practically and financially viable. 

Plastics are here to stay, but problems with their production and use, particularly single-use, have to be addressed. Science comes to the fore when backs are against the wall. Elimination of petroleum as a source material is not in the near future, but there is no question that in the long run research will lead to more biodegradable, recyclable, compostable plastics made from renewable resources. You may soon be drinking from a polyethylene furanoate bottle. Of course, one solution to the plastic problem is not to buy that bottled beverage in the first place.


@JoeSchwarcz

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Jumpin’ Jupiter: Tonight, the giant planet will be closer to Earth than it’s been since 1963 – Vancouver Sun

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Jupiter will orbit just 590 million kilometres from Earth — 375 million km closer than its farthest point — on Sept. 26-27, 2022

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Attention, space geeks: Have you heard about Jupiter getting really close to Earth tonight?

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Well, not really close. The giant gas planet, the largest in our solar system, will still be orbiting 590 million kilometres away. But that’s 375 million kilometres closer than when it’s at its apogee, which is the space geek word for when it’s farthest away.

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Jupiter is viewable like a distant star for much of the year, but it will be especially bright and detailed in the night sky on Sept. 26-27 because it’s closer than it’s been to Earth since 1963 — yup, in nearly six decades.

We asked Marley Leacock, an astronomer and science educator with Vancouver’s H.R. MacMillan Space Centre, a few questions about how best to watch tonight’s rare space spectacle.

When is the best time to see it?

“Jupiter is in the sky pretty much all night,” says Leacock. “It rises in the east at around 7 p.m. and sets at about 7 a.m. tomorrow. The best time to view would be when it is highest in the sky, around 1 a.m. on Sept. 27.”

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Why is it so easily visible right now?

“Jupiter’s visibility has to do with where Jupiter is, but also where Earth and the Sun are,” explains Leacock.

The first reason is that “Jupiter will be in ‘opposition.’ This means that Jupiter will be directly opposite the Sun from our perspective, putting Earth right in the middle of them. When the sun sets in the west, Jupiter will rise directly opposite in the east. Opposition happens about every 13 months.

“The second factor that makes Jupiter so bright is that it is also approaching perigee. Perigee refers to when Jupiter and Earth are the closest to each other in their orbits. Perigee happens about once every 12 months, and the distance between the planets will change due to them being on two different orbits. This perigee, the two planets happen to be in the perfect place to get the smallest distance.

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“The combination of opposition and a close perigee makes the planet appear brighter in our skies.”

A view of Jupiter taken by the James Webb Space Telescope.
A view of Jupiter taken by the James Webb Space Telescope. Photo by NASA /AFP/Getty Images

Is tonight the only time it’s fairly easy to spot?

“Not at all,” says Leacock. “Jupiter is usually visible 10 months out of the year, switching between early morning and late at night. After the opposition, it will start to be in the sky for shorter amounts of time as the months go on. By the beginning of November, it is already high in the nighttime sky by the time the sun sets, and it sets four hours before sunrise.”

By the end of March, it won’t be visible at all. But it will reappear by about the end of May 2023. The next opposition is in early November of next year.

Any tips on how to view it? Do binoculars help?

“Luckily, Jupiter is very bright and easy to spot even in a light-polluted city (like Vancouver),” explains Leacock. “It appears as a very bright star in the sky. I always say to try to get somewhere dark anyways, just to see the stars that appear. An ideal location would be somewhere with high elevation with a clear view of the horizon, especially if you want to see the rise and set.”

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Leacock says typical binoculars will help magnify the planet, but it will still appear star-like. Those with higher magnification might allow you to see it in more detail and possibly even spot its Galilean moons.

True space geeks will want a telescope, though, as “most telescopes with a 60-90 mm aperture will give you a view of the cloud belts and the Galilean moons,” says Leacock.

More good news about tonight’s sky-watching event: The forecast is for perfectly clear skies above Vancouver overnight. Happy viewing.

jruttle@postmedia.com

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NASA moon rocket: Hurricane Ian delays launch – CP24

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Marcia Dunn, The Associated Press


Published Monday, September 26, 2022 5:58PM EDT

CAPE CANAVERAL, Fla. (AP) – Hurricane Ian is prompting NASA to move its moon rocket off the launch pad and into shelter, adding weeks of delay to the lunar-orbiting test flight.

Mission managers decided Monday to return the rocket to its Kennedy Space Center hangar. The four-mile trip will begin late Monday night and could take as long as 12 hours.

The space center remained on the fringes of the hurricane’s cone of uncertainty. With the latest forecast showing no improvement, managers decided to play it safe. NASA already had delayed this week’s planned launch attempt because of the approaching storm.

NASA isn’t speculating when the next launch attempt might be, but it could be off until November. Managers will assess their options once the 322-foot (98-meter) Space Launch System rocket is safely back in the hangar.

A pair of launch attempts were thwarted by hydrogen fuel leaks and other technical trouble.

The $4.1 billion test flight will kick off NASA’s return to the moon since the Apollo moonshots of the 1960s and 1970s. No one will be inside the crew capsule for the debut launch. Astronauts will strap in for the second mission in 2024, leading to a two-person moon landing in 2025.

Meanwhile, NASA and SpaceX are still targeting an Oct. 3 launch of a crew from the U.S., Russia and Japan to the International Space Station. But managers acknowledged that the flight could be delayed as Kennedy braces for the hurricane and its aftermath.

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Jupiter will be its brightest in 59 years Monday. Here's how to see it for yourself – CBC News

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You may have noticed a bright “star” in the eastern sky after sunset, but that’s no star: it’s the mighty planet Jupiter, and it’s almost at its peak brightness.

Jupiter, the largest planet in our solar system, is reaching opposition, an event that occurs when a celestial object rises in the east as the sun sets in the west, putting both the sun and the object on opposite sides of Earth.

But what also makes this special is that the planet will be the closest it has been to Earth in 59 years, meaning it will also be brighter than usual.

The reason planets vary in their distance from Earth is because their orbits aren’t perfectly circular, but rather slightly elliptical.

This image of Jupiter and its moons Io (lower left) and Ganymede (upper right) was acquired by amateur astronomer Damian Peach on Sept. 12, 2010, when Jupiter was close to opposition. South is up and the ‘Great Red Spot’ is visible in the image. (NASA/Damian Peach)

While Jupiter’s opposition happens roughly every 13 months, it’s not common for it to coincide with its closest approach, making this a particularly special treat.

How to see it

At its farthest, Jupiter can be as far as 966 million kilometres away, but on Monday, it will be about 591 million kilometres from Earth. The last time it was this close was in October 1963. And it won’t be this close again until 2129.

You can find the planet in the east after sunset. It’s hard to miss, even from a light-polluted city, as it is the brightest object in the sky. 

As the night progresses, it rises higher into the sky, eventually appearing in the southeast around 11 p.m. ET. on Monday.

You don’t need a telescope or binoculars to see it, but if you do have a pair of binoculars or a telescope, you can have some fun over the coming days. 

One of the special things about Jupiter is its four brightest moons: Callisto, Io, Ganymede and Europa. They orbit Jupiter in a timescale visible from Earth night after night, and even hour after hour — if you’re patient. 

This sky map shows the positions of four of Jupiter’s moons the following night of the opposition, on Sept. 27 at roughly 10:30 p.m. ET. (Stellarium)
This sky chart shows the positions of four of Jupiter’s 80 moons at 10:30 p.m. ET on Sept. 26. (Stellarium)

If you do have a telescope, you can view the moons — and the amazing cloud bands of the gaseous planet, which make for a stunning sight. Also, according to Sky & Telescope magazine, the Great Red Spot will begin its transit — or its crossing — at 8:44 p.m. ET Monday. You can find local times using the publication’s online app or find its app and others like it for your cellphone or tablet. 

Saturn will also be visible in the sky. It currently lies in the south around 10 p.m. ET, but it’s more difficult to spot as it’s not as bright as Jupiter.

You can find several free apps available for download on Android phones and iPhones — such as Stellarium, Star Walk and Sky View — that will help you identify what you see in the night sky, including planets and where to find them.

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