from the world's big
How does fire behave in microgravity? NASA study aims to find out
An ongoing experiment aboard the International Space Station aims to find out more about the fundamentals of combustion.
- In the Confined Combustion project, astronauts aboard the ISS have been igniting fires in controlled spaces in order to study how flames spread in low-gravity spaces.
- Past research has shown that flames spread differently in space. The new project aims to reveal more about how flames spread when ignited in various containers, and on various objects.
- The results could help scientists learn more about how flames spread back on Earth.
How does fire behave in zero-gravity? Scientists aboard the International Space Station are trying to answer that question through Confined Combustion, an ongoing project that involves astronauts igniting and studying flames in different low-gravity spaces.
The goal is to learn more about flame expansion in space in order to improve fire safety for spacecraft, and potentially for future settlements on the moon.
"That is the immediate and most practical goal since NASA can use the knowledge to improve material selection and fire safety strategies," Dr. Paul Ferkul, of the Universities Space Research Association, who is working on the project, told The Guardian.
SpaceX CRS-19 Research Overview: Confined Combustion
Over the past month, astronauts have burned ignited acrylic and various fabrics, examining how the flames expanded within containers of varying shape and size. The low-gravity environment not only reveals how fire spreads in space, but also how fire behaves back on Earth.
That's because in space there's no buoyancy effect, which describes how air rises as it's heated. This effect explains, for example, why a candle flame points upward. But in low gravity, flames expand much differently, taking on strange spherical shapes, and spreading slowly due to low oxygen levels.
"In space, molecular diffusion draws oxygen to the flame and combustion products away from the flame at a rate 100 times slower than the buoyant flow on Earth," Dan Dietrich, FLEX project scientist at NASA's Glenn Research Center in Ohio, told Space.com.
Fire also burns more cooly in low gravity environments. In fact, studies have shown that the spherical shapes of space fires can give rise to "cool flames" that are invisible to the naked eye. These cool flames produce different chemical reactions than hot flames, which could someday lead to the creation of more efficient engine technologies.
"The difference and exciting part of the ISS experiments is that the typical progression on Earth is that a cool flame leads to a hot flame," Daniel Dietrich, a NASA engineer and study co-author, told Motherboard. "The chemical by-products that form in the cool flame burn off in the hot flame. While they burn off, these low temperature or cool flame chemical reactions are of significance in that they are determine engine efficiency and pollutant formation."
The low-gravity environment also provides a unique opportunity to study the fundamentals of combustion, which could help engineers design safer buildings and materials on Earth.
"The equations become significantly easier if we get rid of buoyancy," Ferkul told The Guardian. "We can look at some of the underlying physics that is sometimes masked by buoyancy."
The lower buoyancy, according to past research, also means that some materials would be more flammable in low-gravity environments.
"Living on the moon is a different environment from space station and Earth, and fires will behave differently there," Ferkul said. "There's reason to believe that fires could be more dangerous on the Moon than on Earth."
Join multiple Tony and Emmy Award-winning actress Judith Light live on Big Think at 2 pm ET on Monday.
Construction of the $500 billion dollar tech city-state of the future is moving ahead.
- The futuristic megacity Neom is being built in Saudi Arabia.
- The city will be fully automated, leading in health, education and quality of life.
- It will feature an artificial moon, cloud seeding, robotic gladiators and flying taxis.
The Red Sea area where Neom will be built:
Saudi Arabia Plans Futuristic City, "Neom" (Full Promotional Video)<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="c646d528d230c1bf66c75422bc4ccf6f"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/N53DzL3_BHA?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Frequent shopping for single items adds to our carbon footprint.
- A new study shows e-commerce sites like Amazon leave larger greenhouse gas footprints than retail stores.
- Ordering online from retail stores has an even smaller footprint than going to the store yourself.
- Greening efforts by major e-commerce sites won't curb wasteful consumer habits. Consolidating online orders can make a difference.
A pile of recycled cardboard sits on the ground at Recology's Recycle Central on January 4, 2018 in San Francisco, California.
Photo by Justin Sullivan/Getty Images<p>A large part of the reason is speed. In a competitive market, pure players use the equation, <em>speed + convenience</em>, to drive adoption. This is especially relevant to the "last mile" GHG footprint: the distance between the distribution center and the consumer.</p><p>Interestingly, the smallest GHG footprint occurs when you order directly from a physical store—even smaller than going there yourself. Pure players, such as Amazon, are the greatest offenders. Variables like geographic location matter; the team looked at shopping in the UK, the US, China, and the Netherlands. </p><p>Sadegh Shahmohammadi, a PhD student at the Netherlands' Radboud University and corresponding author of the paper, <a href="https://www.cnn.com/2020/02/26/tech/greenhouse-gas-emissions-retail/index.html" target="_blank">says</a> the above "pattern holds true in countries where people mostly drive. It really depends on the country and consumer behavior there."</p><p>The researchers write that this year-and-a-half long study pushes back on previous research that claims online shopping to be better in terms of GHG footprints.</p><p style="margin-left: 20px;">"They have, however, compared the GHG emissions per shopping event and did not consider the link between the retail channels and the basket size, which leads to a different conclusion than that of the current study."</p><p>Online retail is where convenience trumps environment: people tend to order one item at a time when shopping on pure player sites, whereas they stock up on multiple items when visiting a store. Consumers will sometimes order a number of separate items over the course of a week rather than making one trip to purchase everything they need. </p><p>While greening efforts by online retailers are important, until a shift in consumer attitude changes, the current carbon footprint will be a hard obstacle to overcome. Amazon is trying to have it both ways—carbon-free and convenience addicted—and the math isn't adding up. If you need to order things, do it online, but try to consolidate your purchases as much as possible.</p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
Chronic irregular sleep in children was associated with psychotic experiences in adolescence, according to a recent study out of the University of Birmingham's School of Psychology.