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We’ve all been there: desperately trying to shake the last few drops of ketchup or salad dressing out of the bottle, becoming more and more frustrated as the condiment stubbornly sticks to the sides and refuses to come out.

A few months ago, a group of MIT scientists led by grad student Dave Smith decided to do something a little more productive than shaking. As shown in the video above, courtesy of Fast Company, they created a remarkably slippery substance called LiquiGlide that, when applied as a coating to the inside of bottles, sends viscous condiments like ketchup pouring out in no time.

The team reports that LiquiGlide is made entirely of nontoxic, FDA-approved substances and can easily be applied to the insides of bottles made of glass, plastic and other materials. At first glance, the project seems a little frivolous—are a few drops of ketchup really worth the time of such talented researchers?—but the possible benefits go beyond reducing the annoyance of sandwich-makers and french fry-eaters.

“Everyone is always like, ‘Why bottles? What’s the big deal?’” Smith told Fast Company. “But then you tell them the market for bottles—just the sauces alone is a $17 billion market.” The research team estimates that if all sauce bottles were coated with LiquiGlide, approximates one million tons of wasted condiments would be saved from the trash annually.

How does it work? Details on the proprietary substance are hard to come by, but Smith said, “it’s kind of a structured liquid—it’s rigid like a solid, but it’s lubricated like a liquid.” The research team initially worked on coatings to prevent ice formation on windshields and clogs in gas lines, then realized one of the super-slippery compounds would be ideal for this entirely different use.

Last week, the product won second place in MIT’s $100K Entrepreneurship Competition, and the team has already secured patents on the product. The researchers are reportedly in talks with several bottling and packaging companies, although it’s still early in the process.

Within a few years, though, we might have LiquiGlide-enhanced bottles of ketchup, mayonnaise and salad dressings on the dinner table. And why stop there? Might we see peanut butter, syrup, even honey cascading out of bottles and jars with ease? The possibilities are truly limitless.

Our advice? Get ready for this utopian future by watching a video of mayonnaise coming out of a LiquiGlide bottle:

Will extraterrestrial caves house unusual life forms, as the Katafiki Cave in Greece does? Photo by Vas Gian

In 2007, new images of Mars wowed astronomers and the general public with something out of the pages of a sci-fi comic: extraterrestrial caves. Photos produced by orbiting satellites showed evidence of “skylights” into underground caverns, and thermal imaging indicating that these caves remained at a constant temperature day and night. In recent years, caves and related structures have also been discovered on our moon and on Jupiter’s moon Titan. The concept of extraterrestrial caves has plainly moved from fiction to reality, and scientists are eager to start exploring.

Why is the scientific world so excited about extraterrestrial caves? For many, they represent the next frontier in the search for extraterrestrial life. For others, they are our best bet for someday constructing and maintaining habitable colonies on other planets.

In October 2011, an interdisciplinary group of geologists, cave explorers, earth scientists, astrobiologists and other researchers met in New Mexico for the first time to discuss the science and implications of caves on other planets. Published earlier this month in the journal Eos, the results of the meeting give us a tantalizing hint of what discoveries may come during our lifetimes as space missions begin exploring these hidden crevices throughout the solar system.

Small black depressions are actually skylights into underground caverns on Mars, photographed in 2007. Photo by NASA/JPL/Arizona State University

Caves are a remarkably promising location to begin looking for life, the scientists report. Because they are isolated and protected from the surface, they can provide a diverse range of microenvironments—and the greater number of different habitats, the greater the chance life will happen to evolve in one of them. The study of caves here on earth has shown us that many unusual (and in some cases, downright bizarre) life forms can evolve in caves, and many of these result from the abundance of sulfur, metals and other chemicals that are likely to be available in caves on other planets as well.

The group of researchers also theorized about possible means of exploring caves on other planets and moons. Although images produced by satellites and other spacecraft can sometimes reveal the existence of caves, new technologies are clearly necessary to actually explore their interiors and extract samples that might contain life. Exploration and mapping could hypothetically be undertaken by either human or robotic means, although the latter seems more realistic at this point.

Ground-based exploration vehicles, such as the Mars rovers, could be equipped to enter and navigate caves, but the group noted that such devices would require better autonomous decision-making. Robotic explorers would need to be able to avoid hazards and make decisions about what data to collect without communicating with earth, since the cave walls and ceilings could block the transmission of radio signals.

The scientists even considered how caves can foster human exploration of other moons and planets. They might, for example, be good places to look for ice and other resources that would help groups of humans explore and perhaps even inhabit far-flung extraterrestrial bodies. They could also provide physical protection for colonies and experiments. Close study of caves on earth—their geologic context, the means by which they formed, the microenvironments they provide and other factors—will help us know what to expect in planning cave excursions elsewhere.

Although all of this cave talk sounds a bit like it belongs in a summer Hollywood blockbuster rather than the proceedings of an academic conference, consider this: Exploration of the ocean floor and the moon were both predicted in science fiction before being taken seriously by the scientific establishment. After technology caught up with the human imagination, these ideas didn’t seem so far-fetched.

It may take decades or longer, but it appears as though exploration of extraterrestrial caves is on the same track. What’s more uncertain, though, is what marvels we’ll find when we get there.

The October 3, 2005 annular eclipse, as seen from Spain. Photo by Abel Pardo López

On Sunday evening, for the first time in 18 years, a solar eclipse will be visible from the continental United States. This won’t be your typical eclipse, either—as in the picture above, from October 3, 2005, the moon will cross directly in front of the sun but block out only a portion of its light, leaving a “ring of fire” that is much thicker than the ring seen during most total eclipses.

Why the ring of fire? Total solar eclipses occur when the moon passes directly between the sun and earth, covering up the sun for a brief duration from our vantage point. Because the moon is currently near apogee—meaning it’s at a point in its orbit that is farther from us than usual—the moon appears smaller in the sky, and thus isn’t large enough to block the entire sun. The result: a bold, shimmering ring of fire, known as an annular eclipse.

Unfortunately, those on the East Coast (including us here at Smithsonian) won’t be able to see the eclipse at all, since the sun will set by the time it will occur. Many residents of Western states will be able to see the ring of fire eclipse during the afternoon or evening on Sunday; others will see a partial eclipse, in which the moon crosses in front of the sun off-center, blocking just one portion of it. This NASA map shows the thin swath of the United States that will be able to see the annular eclipse. If you’re outside it, you can click on your exact location to see what time you should look to the sky to see a partial eclipse.

Although up to 94 percent of the sun’s light will be blocked out by the eclipse, looking at it for even a few seconds with the naked eye can cause permanent harm to your retinas. (Don’t try watching with your smartphone or digital camera, either—it can damage the lens.) Instead, punch a small hole in a piece of cardboard and allow the sun’s light to pass through it, and you’ll see a projected image of the eclipse on the ground. You can also look to the shaded ground beneath a leafy tree to see the shadows turn into circular rings of light.

Watch the video below by Science@NASA for a full explanation of the astronomical phenomenon:

A new study indicates 3.6 percent of American adults are prone to sleepwalking, but scientists still don't understand what causes the phenomenon. Photo by Soffie Hicks

A study in Tuesday’s issue of Neurology revealed something surprising about American nighttime habits—we like to walk. The first-ever large-scale survey of sleepwalking habits in American adults indicated that an estimated 3.6 percent of us—more than 8.4 million people—have had an episode of nocturnal wandering in the past year. This is much higher than researchers expected. Nearly 30 percent of respondents reported sleepwalking at some point in their lives.

“The study underscores the fact that sleepwalking is much more prevalent in adults than previously appreciated,” the researchers, led by Maurice Ohayon of Stanford University, noted in the study. “The numbers are very big.” For comparison, the sleep disorder narcolepsy affects an estimated .04 percent of the population.

Sleepwalking can take a number of forms, from brief periods of wandering to activities as complicated as cooking, cleaning and even driving a car. In 2004, an Australia woman reportedly had repeated sex with strangers over the course of several months while sleepwalking, and in rare instances, it has been used as a defense in trials for homicide and other crimes.

Despite the surprising prevalence of this phenomenon, though, scientists still don’t understand what causes it.

The American Academy of Sleep Medicine divides our sleep time into two categories—REM sleep and non-REM (NREM) sleep, depending on whether REM (rapid eye movement) is occurring underneath the eyelids. During REM sleep, the brain’s neuronal activity is most similar to when it is awake, and that’s when we do most of our most vivid dreaming.

Paradoxically, though, sleepwalking occurs during NREM sleep. Normally, adults go through sleep cycles: from the lightest stages of NREM to the deepest NREM, and then back to the lightest NREM and then REM, every one and a half hours or so. Sleepwalking typically occurs during the deepest stages of NREM—the part of the sleep cycle that, if interrupted, leaves you the most groggy. It usually happens during the first third of the night and can last anywhere from 30 seconds to 30 minutes. Some scientists speculate that it is caused by the brain attempting to directly transition from deep NREM sleep to wakefulness, rather than going through the subsequent stages of the sleep cycle.

One factor that seems to increase the likelihood of sleepwalking is simply the amount of time people spend in this deepest stage of sleep. Sleep deprivation, fever and excessive tiredness can increase the odds that an individual will sleepwalk. Additionally, over-the-counter sleeping pills and SSRI (selective serotonin reuptake inhibitor) medications, commonly prescribed to treat depression, are known to increase the duration of deep sleep.

Thus, it’s not entirely surprising that the Neurology study found that sleepwalking is positively correlated with a number of mental disorders, such as clinical depression, alcoholism and obsessive-compulsive disorder. People who take SSRIs or sleeping pills are much more likely to sleepwalk at least twice a month than those who don’t.

“There is no doubt an association between nocturnal wanderings and certain conditions,” said Ohayon of the survey’s results, which sampled 19,136 individuals from 15 states. “But we don’t know the direction of the causality. Are the medical conditions provoking sleepwalking, or is it vice versa? Or perhaps it’s the treatment that is responsible.”

Overall, children sleepwalk far more often than adults, and the phenomenon is not strongly associated with a particular gender. The study found that most sleepwalkers experience the phenomenon chronically, as 80 percent who reported sleepwalking had done so for more than five years. Additionally, 30 percent had a family history of sleepwalking.

Experts disagree about what you should do if you see someone sleepwalking. While it may be amusing, it can often be dangerous, but some believe that suddenly waking the sleeper can cause excessive disturbance.

“Make sure they are safe. If at all possible, gently try to steer them toward their bed. If they resist, let them be,” neurologist Gayatri Devi told WebMD. “Make sure there is a lock on the door and the window,” Ohayon says. “They don’t realize what they are doing.”

Andrew Adamatzky is a professor in Unconventional Computing at the University of the West of England, and throughout his career he has indeed taken an unconventional approach to computing. Instead of servers and microchips, he uses a single-celled slime mold. The brainless, seemingly unintelligent organism (Physarum polycephalum) has been harnessed to transfer specific colors between foods dyed with food coloring, move a small boat through a gel medium and even solve mazes.

His latest project, though, is perhaps the most unconventional of all. Over the past several years, he and Andrew Ilachinski of the Center for Naval Analyses have used the slime mold to do something astoundingly complicated: design plans for national highway systems. And each time, within days, the mold created routes that are remarkably similar to actual systems designed by human engineers.

The slime mold, it turns out, is specifically evolved to do one thing very well: efficiently transport nutrients from one location to another. As the pair of researchers explained in a New York Times op-ed this past weekend, the forest-dwelling organism forages for microscopic nutrient particles by sending out protoplasmic tubes of slime and maintaining the links between these food sources as efficiently as possible.

So Adamatzky, Ilachinski and a team of colleagues decided to use this ability to determine exactly which routes would be most logical to build if one were designing, say, the U.S. Interstate Highway System from scratch. As detailed in an article that will soon appear in the journal Complex Systems, the team replicated the United States for the mold by overlaying a agar gel dish shaped like the country on top of a map and placing a food source (rolled oats) in each of the 20 most populous metropolitan areas. They repeated the experiment for 13 other geographical areas, including Brazil, Africa and Germany, and replicated it several times for each map.

A slime mold is used to design an efficient U.S. interstate system. Photo by Andrew Adamatzky, University of the West of England

After placing the oats, they let the slime mold spread naturally from the largest city or capital, and observed what routes it determined were most efficient for transporting the nutrients across the country. As depicted in the video above (showing one of the experimental trials for Canada) and the image to the right (showing the results of a trial for the United States), the slime mold repeatedly created routes that were strikingly similar to the ones laid out by decades—and sometimes centuries—of human engineering.

“Physarum is renowned for building optimal transport networks, which minimize distance of cytoplasmic transfer but also span as much sources of nutrients as possible,” Adamatzky told Wired last year. “Ideally, human-built roads should fulfill the same criteria.”

Indeed, it seems that the U.S. Interstate Highway System does fulfill the same criteria, as the mold created routes that match the majority of interstates. In nearly every trial, the mold grew links that correlate with Route 95 from New York to Boston and Route 45 from Dallas to Houston; In most trials, the mold closely replicated highways that span the major cities of the southwest (Denver, Albuquerque, Phoenix and Los Angeles) and the eastern seaboard (Route 95 all the way from Boston to Jacksonville).

The mold’s designs correlate even more closely with Belgium, Canada and China’s highway systems, suggesting that those are more efficient in terms of minimizing travel distance between population centers and spanning as many densely populated areas as possible.

Why do the mold’s and humankind’s route creations match so closely? The authors speculate that, because many early roads were determined based on prehistoric human footpaths and animal trails, and many modern highways are in turn based on these early roads, our design process is really not so different from the slime mold’s: using trial and error to find the most convenient paths for travel over time.

The experiments are fascinating—and maybe a little creepy—in the way they demonstrate that seemingly unintelligent life forms can perform extremely complicated tasks. But they also hint at potential applications in the real world. Adamatzky seeks to devise means of problem-solving that are cheaper and simpler than silicon-based computing, and the mold has already been used to solve a number of arcane spatial mathematical problems. The mold requires relatively little expertise or laboratory resources to use, and it is a more sustainable computing option than traditional electronic circuitry.

One practical application that immediately comes to mind is using the mold to analyze which routes would be most efficient to build for countries that don’t yet have developed national highway systems. They could also be used to efficiently model ideal pathways on a much smaller scale, such as a college campus or public park.

Regardless of what we might end up using it for, one thing is already clear: the brainless slime mold is much smarter than we think.