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.

For his 65th birthday, Stephen Hawking took a ride in zero gravity. Photo: Associated Press

On January 8, 2007, scientist Stephen Hawking did something special for his 65th birthday—he took a trip up into zero gravity. He rode in the Zero Gravity Corporation’s modified Boeing 727 jet, which traveled up to 24,000 feet over the Atlantic Ocean off the coast of Florida and performed a series of dips that let Hawking experience a total of about four minutes of weightlesness. Because Hawking suffers from a degenerative nerve disease related to amyotrophic lateral sclerosis, a medical support team was on hand to monitor his blood pressure and cardiac readings. But the renowned physicist held up even better than expected, negotiating for two additional 30-second rounds of weightlessness while in flight.

NASA has been using aircraft to simulate the zero-gravity environment of orbit for decades, and in 2004 the Zero Gravity Corporation became the first company to offer the experience to the general public. The sensation occurs as the plane climbs upward with a very steep pitch and then levels out—a little like the feeling you get at the top of a roller coaster—and lasts about 30 seconds at a time. The price tag: $4,950 plus tax.

Hawking took the flight in order to publicize the possibility of commercial space travel. “I believe that life on Earth is at an ever-increasing risk of being wiped out by a disaster such as sudden nuclear war, a genetically engineered virus, or other dangers. I think the human race has no future if it doesn’t go into space,” he said before the flight. Using the force of commerce, he believes, is the most practical way to eventually make mass space travel a real possibility.

After the flight, Hawking was exuberant, and discussed his hopes to someday fully enter earth’s orbit (Richard Branson, owner of the company Virgin Galactic, has said he will waive the $200,000 fee). “It was amazing. The zero-G part was wonderful, and the high-G part was no problem,” Hawking said. “I could have gone on and on. Space, here I come.”

Opinions vary on what caused the Hindenburg to explode so suddenly.

On May 6, 1937—75 years ago this week—the Hindenburg airship was about the complete its 35th trip across the Atlantic, having departed from Frankfurt, Germany and nearly arrived at Lakehurst, New Jersey. Then, suddenly, after thousands of miles of uneventful travel, the great zeppelin caught fire while less than 300 feet from the ground. Within a minute of the first signs of trouble, the entire ship was incinerated, and the burning wreckage crashed to the ground. Thirty-five of the 97 people on board perished in the disaster.

Then the finger-pointing began. From the very start, observers disagreed about what exactly sparked the explosion and what caused it to burn so quickly. In the years since, scientists, engineers and others have used science to weigh in on the debate and attempt to solve the mystery of the Hindenburg.

During an era of tension between the United States and Germany’s new Nazi government, suspicious minds quickly alighted on the idea that a crew member or passenger had sabotaged the airship, intentionally starting a fire. However, nothing more than circumstantial evidence was ever put forth to support the idea. Realistic alternatives for the cause of the explosion include a buildup of static electricity, a bolt of lightning or a backfiring engine, but at this point it’s impossible to determine what exactly caused the spark.

A different question is what provided the fuel for the explosion—and this is where the science really gets interesting. Initially, observers assumed that some of the lighter-than-air hydrogen that kept the ship aloft somehow leaked from its enclosed cells, mixing with the oxygen in the air to create an incredibly flammable substance. Photographs taken right after the initial explosion show lines of fire along boundaries between the fuel cells, and crew members stationed in the stern reported seeing the actual cells burn, supporting the idea that leaking hydrogen caused the craft to explode so violently. Many have theorized that, during one of the sharp turns the ship took just before exploding, one of the bracing wires inside snapped, puncturing one of the cells.

Then, in 1996, retired NASA scientist Addison Bain, who had years of experience working with hydrogen, presented a new idea: the incendiary paint hypothesis. As part of his argument that hydrogen can be safely used for transportation and other purposes, Bain claimed that the fire was initially fueled by a special paint used on the zeppelin’s skin. The varnish compound included chemicals such iron oxide, which can be used as rocket fuel.

Bain also pointed out that the hydrogen inside the cells had been given a garlic scent, to help crew members detect a leak, but no one reported smelling garlic at the time of the explosion. He also said that a fire fueled by hydrogen would produce a blue flame, but the fire was a bright red. In his scenario, the mystery spark would have ignited the varnish rather than leaking hydrogen—meaning that a design flaw, rather than the inherent risks of hydrogen, had caused the disaster.

In 2005, a team of researchers led by A.J. Dessler, a physicist at Texas A&M, published a detailed study in which they attempted to determine whether the chemicals in the varnish could possibly account for the fire. Their answer: no way. Their calculations indicate that, if fueled by the paint alone, the airship would have taken roughly 40 hours to burn completely, rather than the 34 seconds it took for it to be consumed. In the lab, they burned replica pieces of the Hindenburg‘s outer covering, which confirmed their theoretical calculations—and indicated that the paint alone could not have fueled the fire.

So, more than 75 years later, we’re still not quite sure what to believe about the Hindenburg disaster. Can the use of hydrogen gas in transportation be safe? Or is a vehicle filled with flammable gas simply an accident waiting to happen? However it was caused, the terrible explosion had one long-lasting effect: It permanently put airship travel on the back burner.

Read about a new exhibit at the Smithsonian’s National Postal Museum about the Hindenburg and read an eyewitness account of the disaster from a grounds crew member.

Acanthaspis petax, a type of assassin bug, stacks dead ant bodies on its back to confuse predators. Photo by Mohd Rizal Ismail

Imagine you’re wandering in the forests near Lake Victoria, in Kenya or Tanzania, when you spot something strange crawling on a leaf. It looks like a dozen or so ants, stuck together in a ball. But look more closely and you’ll see the ants are dead. And there’s a nasty-looking insect underneath, hauling these ants corpses along like a miniature backpack.

This is Acanthaspis petax, a member of the Reduviidae family, which is found in East Africa and Malaysia. Like other assassin bugs, it hunts its prey by piercing it with its proboscis, injecting paralysis-inducing saliva and an enzyme that dissolves tissue, then sucking out the innards. But unlike other bugs, it then fashions empty ant exoskeletons into protective outerwear. The insect can carry as many as 20 dead ants at a time, and binds them together with a sticky excretion into a cluster that may be larger than its own body.

For years, scientists debated why Acanthaspis petax engaged in this unusual behavior. It hunts several different types of prey, but appears to exclusively stack ant bodies on its back. Some suggested that the ant corpses may provide olfactory camouflage when hunting, while others thought the mound of bodies may be used as a visual distraction for larger creatures that are hunting the assassin bug.

Photo by Mohd Rizal Ismail

In 2007, a team of researchers from New Zealand carried out an experiment to test whether the insect’s corpse-carrying strategy truly helped protect it from predation. In the study, they left assassin bugs alone in glass cages with several species of jumping spiders, which are their natural predators. Some of the insects were carrying balls of ant carcasses on their backs (the researchers called these “masked” bugs) while others were left naked. Since the jumping spiders have excellent vision but a poor sense of smell—they hunt by using their acute sense of sight to make a precisely gauged leap and land on their prey—the experiment would indicate if the ant bodies served as visual camouflage or not.

The result: the spiders attacked the naked bugs roughly ten times more often than the masked ones. The researchers even repeated the experiment with dead, preserved assassin bugs, to control for the effects of movement and behavior, and the results remained the same. Carrying that ball of dead ants, it turns out, is a great strategy for the assassin bug to use in trying to survive for its next meal.

The scientists speculate that the large mound of corpses changes the visual form of the insect to the point where the spiders can’t recognize it as prey.

But why do the assassin bugs refrain from using other insects in the same way? The researchers suggest that Acanthaspis petax may actually be relying on the spiders’ inherent reluctance to attack ants. Because ants have a tendency to swarm and may secrete chemical weapons, the spiders don’t typically hunt them.

Good strategy for Acanthaspis petax. Raw deal for the ants.

Scientists calculated how to make a force field big enough to fit the Millennium Falcon. Photo courtesy of Mary Evans / Lucas Film / Ronald Grant / Everett Collection (10336353)

Today, if you aren’t already aware, is something of an intergalactic holiday. In recent years, May 4th has become an unofficial day to honor the iconic film series Star Wars, because the date is a rhyming pun of the signature line, “May the Force Fourth Be With You.” All around the world, Star Wars fans are celebrating Luke, Leia, Boba Fett and (maybe even) the Ewoks.

We decided to channel our inner Jedi by checking out the contributions science has made towards a better understanding of the Star Wars universe. Last year, it turns out, a team of physicists from the University of Leicester in Britain took a closer look at many fans’ favorite spacecraft: Han Solo and Chewbacca’s hyperspace-traveling Millennium Falcon (which made the Kessel Run in less than 12 parsecs!)

The scientists noted that force fields are often employed in the Star Wars universe to provide a barrier between the hangars of spaceships and outer space, preventing the ship’s atmosphere from being sucked outwards (think of spacecraft flying inside the Death Star‘s massive hangar bay, with no mechanical airlock). The physicists noted that a real-life innovation, the plasma window, could theoretically serve to create such force fields. Plasma windows, invented by Brookhaven Lab physicist Ady Hershcovitch in 1995, use magnetic fields to create bounded areas filled with plasma (superheated, viscous ionized gas), which have the special property of blocking air from entering a vacuum while allowing radiation and physical objects to freely pass through.

With this knowledge in hand, the research team decided to try calculating the amount of energy that would be necessary to create a docking force field large enough to accommodate the Millennium Falcon, which they estimate is roughly 100 by 40 by 6 feet. Their conclusion? Theoretically possible with current technology—but generating sufficient amounts of energy to continuously sustain a force field that size is unlikely to be feasible.

But, in a galaxy far, far away, anything is possible.

The supermoon of March 2011, rising behind the Lincoln Memorial In Washington, DC. Photo by NASA/Bill Ingalls

This Saturday evening, take a look at the night sky and you might see something special. The moon will make its largest, most stunning appearance of the year—an event known to scientists as “the perigee-syzygy of the Earth-Moon-Sun system” and to the popular skywatching public simply as the “supermoon.” As one of the most spectacular supermoons in years, the moon will appear 14 percent bigger and 30 percent brighter than when it is on the far side of its orbit.

Why does the moon sometimes appear larger, and sometimes smaller? The answer lies in the fact that its orbit around Earth is elliptical, so its distance from us varies—it ranges from roughly 222,000 to 252,000 miles away each month. On Saturday, the moon will reach what is known as the perigee, coming as close as it ever does to the Earth, just 221,802 miles away. At the same time, it will be a full moon, with the entirety of its Earth-facing surface illuminated by the light of the sun.

This supermoon will appear especially large because the exact moment of perigee will neatly coincide with the appearance of a perfectly full moon. The full moon will occur at 11:34 p.m. EST, and the perigee will occur at 11:35. During last year’s supermoon on March 19, 2011, for comparison, the perigee and full moon were 50 minutes apart.

A comparison of last year's March supermoon (right) with an average moon from December 2010. Photo by Wikimedia Commons user Marcoaliaslama

“The timing is almost perfect,” says NASA, according to the Washington Post. AccuWeather’s astronomy blogger Daniel Vogler notes that a look through recent data reveals no more closely-timed (and therefore bigger) supermoons.

Apart from providing a sight to behold in the night sky, the moon’s perigee also has a tangible effect on Earth: It causes higher than normal tides. Because tides are driven by the moon’s gravitational effects, a closer moon means that the oceans will be pulled more than usual towards the satellite. In most places, this will mean a tide that is an inch or so higher than usual, but geographical factors can multiply the effect up to around six inches.

There has long been speculation that the moon’s gravitational effect during its perigee could be the cause of natural disasters, including earthquakes and volcanic activity. In particular, many suggested this link following the earthquake and subsequent tsunami off the coast of Japan in March of 2011. However, the devastating quake occurred over a week before the supermoon, and studies have shown no strong evidence for increased frequency of high-intensity seismic activity during the moon’s perigee.

There are more concrete examples, though, in which supermoons may cause problems. In particular, flooding during storms may be made more severe because of the higher tides. In 1962, the coincidental arrival of a powerful storm with the moon’s perigee inundated the entire Atlantic coast of Cape Cod, causing 40 deaths and $500 million in property damage.

On Saturday, assuming no damaging storms or floods are at your doorstep, just hope for a clear night and take a look outside. The moon will appear larger and brighter than usual all night, but for the most striking views, try to catch it just after it rises above the horizon, when an optical illusion causes it to look larger than it really is, and viewing it through the gases of the earth’s atmosphere can cause the moon to appear yellow, orange or red in color.

An Aguilla Bank skink, one of the 24 new species discovered. Photo by Karl Questel

We live in an age of alarming extinction, in which many species are lost in large part due to human activity. At the same time, the natural world is so complex that even after centuries of research, scientists are still rapidly discovering new species everywhere from mountain tops to rain forests to the ocean floor.

This paradox is aptly illustrated by an announcement made yesterday: 24 new species of lizards, known as skinks, have been discovered in the Caribbean islands. But half of them may be close to extinction, and some may already extinct in the wild.

The research was conducted by a team led by Blair Hedges, a biologist at Penn State University and one of the world’s foremost experts at identifying new forms of life. Previously, Hedges has been involved with the discovery of what were then the world’s smallest snake, lizard and frog. The two dozen species named in this paper, published in the journal Zootaxa, constitute one of the largest mass discoveries of lizards in centuries.

To identify the many species of skinks (formally, members of the family Scincidae), Hedges and his team examined specimens housed at zoos and conservation centers around the world. By comparing taxonomic features of the lizards (such as the shapes of scales) and using DNA analysis, they determined that there are a total of 39 distinct species of skinks that live in the Caribbean—6 species that were previously recognized, 9 that had been named long ago but had been considered invalid and the 24 entirely new ones.

A Caicos Islands skink. Photo by Joseph Burgess

“Now, one of the smallest groups of lizards in this region of the world has become one of the largest groups,” Hedges said in a press release. “We were completely surprised to find what amounts to a new fauna, with co-occurring species and different ecological types.” He has determined that the skinks came to the Americas roughly 18 million years ago, likely arriving from Africa on floating rafts of vegetation.

How did the skinks go unnoticed for so long? Hedges speculates that because large numbers of skinks had already disappeared by the start of the 20th century, scientists, tourists and local residents have been much less likely to encounter them in the years since. Additionally, many of the characteristics that distinguish the species from one another have been overlooked or weren’t detectable until now, especially those indicated by DNA analysis.

The researchers determined that the skinks have long been most threatened by an exotic intruder: the mongoose, introduced from India to Cuba in 1872 with the intention of reducing rat populations in sugarcane fields. Rat populations were partially controlled, but by 1900, nearly half of the islands to which the mongoose had spread were also without skinks, and the remaining lizards have dwindled in population ever since. Additionally, the researchers note, current human activities such as forest removal are likely contributing to the skinks’ endangered status. The research team hopes that their data will be used to plan future conservation efforts.

Theoretically, if you’re in the U.S. Virgin Islands, Trinidad and Tobago, or Martinique, you might try looking for a skink. But because each of the species is remarkably rare—with even the non-endangered ones qualifying as vulnerable—it’ll certainly be difficult. Above all, if you do want to find one, hurry up: there may not be much time left.

The rare all-white orca whale was spotted swimming with its pod. Photo by E. Lazareva / Newscom

On a summer morning in 2010, off the coast of Kamchatka in eastern Russia, scientists made a rare discovery. Photos, released earlier this week (and posted on our Retina Tumblr blog) document what may be the first verified sighting of its kind: an all-white adult orca whale. Also known as “killer whales,” orcas are typically a mix of black and white. White members of several other whale species have been seen previously, but so far, the only known white orcas have been young.

This one, nicknamed “Iceberg” by the researchers, sports a six-foot-tall dorsal fin, indicating that it is an adult. The scientists, led by Erich Hoyt of the Whale and Dolphin Conservation Society, are are unsure why this whale has such unusual pigmentation. Although it is mostly white in color, it may not qualify as albino due to some color in the area behind the dorsal fin. One previously known young albino orca, a resident of a Canadian aquarium named Chima, suffered from a rare genetic condition that caused a number of medical complications, but Iceberg appears to be a healthy member of its pod.

The most heavily worn payer in the manuscript was dedicated to St. Sebastian, who was thought to be efficacious against the bubonic plague. Image courtesy of the University of St. Andrews

When medieval Europeans read religious texts, what were their favorite prayers? Which sections did they return to time and time again, and which parts perpetually put them to sleep?

These questions have long seemed unanswerable, but a new method by Kathryn Rudy of the University of St. Andrews in Scotland takes them on with an unexpected approach: examining the dirt on a book’s pages.

Rudy hit on the technique when she realized that the amount of dirt on each page was an indication of how frequently the pages were touched by human hands. Dirtier pages were probably used most frequently, while relatively clean pages were turned to much less often. She determined the amount of dirt on each page and compared the values to reveal what passages were most appealing to medieval readers—and thus, what sorts of things they cared about while reading religious texts.

The densitometer used to analyze the amount of dirt on each page. Image courtesy of the University of St. Andrews

In a press release, Rudy said:

Although it is often difficult to study the habits, private rituals and emotional states of people, this new technique can let us into the minds of people from the past…[books] were treasured, read several times a day at key prayer times, and through analysing how dirty the pages are we can identify the priorities and beliefs of their owners.

To gather the data, she put a densitometer to work. The device aims a light source at a piece of paper and measures the amount of light that bounces back into a photoelectric cell. This quantifies the darkness of the paper, which indicates the amount of dirt on the page.

Rudy then compared each of the pages in the religious texts tested. Her results are simultaneously predictable and fascinating: They show us that the worries of medieval people were really not so different from ours today.

At a time when infectious diseases could ravage entire communities, readers were deeply concerned with their own health—the most heavily worn prayer in one of the manuscripts analyzed was dedicated to St. Sebastian, who was thought to protect against the bubonic plague because his arrow wounds resembled the buboes suffered by the plague’s victims. Prayers for personal salvation, such as one that could earn a devoted individual a 20,000-year reduction of time in purgatory, were much more heavily used than prayers for the salvation of others.

Perhaps most intriguingly, Rudy’s analysis even pinpointed a prayer that seems to have put people to sleep. A particular prayer said early in the morning hours is worn and dirty for only the first few pages, likely indicating that readers repeatedly opened it and started praying, but rarely made it through the whole thing.

The research is fascinating for the way it applies an already developed technology to a novel use, revealing new details that were assumed to be lost to history. Most promisingly, it hints at the many untapped applications of devices such as a densitometer that we haven’t even imagined yet. What historical texts would you want to analyze? Or what other artifacts do you think still have something new to tell us if we look a little closer?

NASA's Voyager probes are now exploring the outer reaches of the solar system

In 1977, the twin Voyager probes were launched by NASA with a radical mission in mind: after studying Jupiter and Saturn, scientists and engineers hoped the probes would become the first-ever human-made objects to exit the solar system.

Nearly 35 years later, data coming back from one of the probes indicates that they’re close but haven’t made it out of the solar system just yet.

According to a study published this month in Geophysical Research Letters, Voyager One is now approximately 111 astronomical units from the sun—meaning that it is 111 times farther from the sun than is the Earth. However, even drifting at this great distance, the probes continue to transmit back fascinating information about this previously uncharted area of the solar system, known as the heliosheath, where the outgoing particles of solar wind emanating from the sun are slowed by the pressure of interstellar gas.

The Voyagers are still within the heliosheath, the outer layer of the solar system

Most recently, Voyager One detected increases in the intensity of low-energy cosmic ray electrons. As a result, scientists have concluded that the probe is has not yet passed the heliopause—generally considered the outer boundary of the solar system, where the solar wind is stopped by the interstellar medium—because outside the solar system, this electron intensity is assumed to be constant. These unexpected spikes in electron intensity may be evidence of different regions in the outer heliosheath, helping us better understand the heliospheric “bubble” where the solar system butts up against interstellar space.

In the years since their launches, the Voyagers have made a number of stunning discoveries. They’ve photographed the active volcanoes on Jupiter’s moon Io, helped us better understand the intricacies of Saturn’s rings and were the only spacecraft to visit Neptune and Uranus. Scientists back on Earth hope that the probes will gather as much information as possible before their plutonium power sources fail and they stop transmitting data forever, projected to occur sometime between 2020 and 2025.

Even after that, though, the Voyagers might have an even more significant role to play: They may serve humanity’s time capsules for future alien civilizations. Each probe carries a ”Golden Record,” Carl Sagan’s brainchild, which was designed to communicate the essence of human civilization to any forms of life they may encounter. The records contain everything from photographs of the structure of DNA to the sound of human brainwaves to greetings in 55 different languages to popular music from a wide range of different cultures, including Chuck Berry’s “Johnny B. Goode.”

In this month’s issue of Smithsonian, Timothy Ferris, who helped design the records, reflects upon the remarkable journey they have already undertaken and the amazing possibilities of what they may encounter in years to come. Ferris writes:

The Voyagers will wander forever among the stars, mute as ghost ships but with stories to tell. Each carries a time capsule, the “Golden Record,” containing information about where, when and by what sort of species they were dispatched. Whether they will ever be found, or by whom, is utterly unknown. In that sense, the probes’ exploratory mission is just beginning.

Monday's solar eruption at its peak moment. Photo courtesy of NASA

On Monday, NASA’s Solar Dynamics Observatory telescope recorded an awesome sight: one of the most visually spectacular solar eruptions in years. The mass of super-hot gases and charged particles exploded from the east limb of the sun, which is the left side for observers on earth. The false-color image above captures the prominence at its peak, showing charged particles from the sun’s magnetic field rising up from the surface.

Solar prominences occur when these charged particles interact with the sun’s plasma, and are often associated with solar flares, which are momentary brightenings of the sun’s surface. The flare that accompanied this prominence rated an M1.7 on the Richter scale for solar flares, making it a medium-size event, but since it was not aimed toward Earth, it has had no effect on satellites or air travel.

As captured in the video below, some of the particles did not have enough force to break away from the sun, and can be seen falling back toward its surface afterward. Have a look: