10 SPECTACULAR MOONS IN OUR SOLAR SYSTEM

10 spectacular moons in our solar system
By Katherine Butler, Mother Nature Network, 9 October 2018.

Magnificent satellites

Earth's moon shines brightly in our sky, but it is not the only satellite in our solar system. Experts estimate there are as many as 170 to 180 moons orbiting the eight planets of our section of the galaxy. A moon is defined as a satellite that orbits a planet. Moons are named after Roman and Greek gods and demigods - with colors and mystifying landscapes that match their fanciful namesakes. Here's our look at some of the beautiful, bold and essentially unexplained moons of our solar system. Pictured here [top image] is a false color image from NASA of Saturn's moon, Rhea.

Jupiter's Europa

Photo: NASA/JPL-Caltech/SETI Institute

This image details the frozen surface of Europa, one of Jupiter's estimated 69 known moons. Europa was named after a lover of Zeus, the Greek counterpart of Jupiter. NASA took this enhanced-color image from the Galileo spacecraft, which circled the largest planet on our solar system until 2003. NASA says the red lines are cracks and ridges are most likely created by the intense gravitational pull of Jupiter. As NASA writes, "Color variations across the surface are associated with differences in geologic feature type and location. For example, areas that appear blue or white contain relatively pure water ice, while reddish and brownish areas include non-ice components in higher concentrations." Europa is one of Jupiter's largest moons.

Europa's surface may also be covered in massive "ice spikes" as high as 50 feet tall, according to a 2018 study. The spikes would be similar to penitentes on Earth, which are snow formations found at high altitudes.

In order for these spikes to even form, "the ice must be sufficiently volatile to sublimate under surface conditions and diffusive processes that act to smooth the topography must operate more slowly," wrote the study's authors.

While there is no visual evidence of penitentes on Europa, scientists say radar and thermal data support the idea that conditions on Europa could allow for these ice spikes to form.

Neptune's Triton

Photo: NASA/JPL

This photo, taken by NASA through green, violet and ultraviolet filters, shows the bright southern hemisphere of Triton. Triton is named after the Greek sea god Triton, the son of Poseidon (the Greek god comparable to the Roman Neptune). Triton is the only Neptune moon that has an internal geology; it is known to have geological activity like geysers and volcanic activity. It is one of very few such moons in the solar system. Experts believe that Triton could have been a captured object from the nearby Kuiper Belt, where the dwarf planet Pluto and other objects reside. Triton is the largest of Neptune's moons and the only object that orbits any planet in a retrograde orbit. Just like our own moon, it is locked in a synchronous rotation with its home planet.

Jupiter's Io

Photo: NASA/JPL/University of Arizona

Io is the closest large moon of Jupiter and was named for a priestess of Hera who became one of the lovers of Zeus. Io has the most volcanic activity of any moon in the solar system, and its entire surface is covered with lava every few thousand years. NASA notes that this photo is based on real infrared, green and ultraviolet-light images and has only been adjusted to show the contrast. Io has an irregular elliptical orbit and is slightly larger than our own moon. It was discovered in 1610 by Galileo.

Mars' Phobos

Photo: NASA/JPL-Caltech/University of Arizona

One of only two Martian moons, Phobos has been described as no more than a tiny rock. NASA also notes that Phobos is on a collision course with Mars. As NASA writes, "It is slowly moving towards Mars and will crash into the planet or break apart in about 50 million years." It has a six-mile gouge in it called the Stickney crater, which experts believe was caused by a meteorite impact. Phobos is named for one of the mythical sons of the Greek god Ares, who is the Greek equivalent of the Roman god Mars.

Jupiter's Ganymede

Photo: NOAA/Wikimedia Commons

Ganymede is the largest moon in our solar system. In fact, it's bigger than the planet Mercury and the dwarf planet Pluto, and it is almost three-quarters the size of Mars. NASA explains that if Ganymede orbited the sun instead of Jupiter, it would be a planet. There is evidence of a thin oxygen atmosphere on Ganymede, but experts believe it is too thin to support life. Ganymede also sports a thin magnetic field, indicating that this moon can teach us a lot.

Uranus' Oberon

Photo: NASA/JPL/Wikimedia Commons

Oberon is named for Shakespeare's King of the Fairies from "A Midsummer Night's Dream." It is the second largest moon of Uranus, and was first studied when NASA's Voyager 2 flew by in 1986. This photo, taken by Voyager 2, shows "several large craters in Oberon's icy surface surrounded by bright rays similar to those seen on Jupiter's moon Callisto." Like the rest of Uranus' large moons, Oberon is mostly made of ice and rock. It was first discovered in 1787 by astronomer William Herschel. At present, Uranus has about 27 named moons.

Jupiter's Callisto

Photo: NASA/JPL/DLR

NASA reports that Callisto is the third largest satellite in the solar system and roughly the size of Mercury. Pictured here in color, NASA points out that its many markings show a turbulent history of collisions with space objects. In fact, Callisto is known to be the most heavily cratered object in our solar system. And while Callisto is uniformly cratered, it is not uniformly colored. Experts believe the different colors come from ice and ice erosion. It is the darkest of Jupiter's four largest moons, known as the Galilean satellites. But it is still twice as bright as our moon.

Saturn's Mimas

Photo: NASA/JPL/SSI/LPI

This color-enhanced view of Mimas from NASA shows a bluish band around the equator. Experts are unsure of the nature of this blue band, though NASA speculates it could have something to do with the high-energy electrons that drift in an opposite direction to the flow of plasma in the magnetic bubble around Saturn. As NASA reports, Mimas is named for a giant who was killed by Mars in the war between the Titans and the gods of Olympus. It is the smallest and innermost of Saturn's major moons. Some note that its giant impact crater makes it similar to the Death Star featured in the "Star Wars" series.

Earth's moon transiting the sun

Photo: NASA/STEREO

Our moon is one of the largest satellites in the solar system, which is impressive considering how much smaller the Earth is compared to Jupiter or Saturn. It has a diameter of 2,160 miles, as opposed to 3,280 miles, the diameter of Jupiter's Ganymede, the largest satellite. Most experts agree that the moon formed when a Mars-sized planet collided with Earth several billion years ago. The ensuing debris cloud reformed into the moon. Here the moon is seen in a NASA composite image transiting the sun from the STEREO-B spacecraft.

Top image: False-color image of Saturn's moon Rhea. Credit: NASA/JPL/Space Science Institute.

[Source: Mother Nature Network.]

10 FUTURISTIC TECHNOLOGIES WE ACTUALLY NEED

10 Futuristic Technologies We Actually Need
By Gregory Myers, Toptenz, 15 October 2018.

People watch sci-fi movies and get excited by the crazy ideas presented. Some of them even go on to become scientists or inventors, and many have helped bring the world inventions that mimic what they once saw in movies. In a way, these people are making a specific vision of the future happen, but some of these inventions aren’t really practical and are really more a form of wish fulfillment than they are moving humanity’s scientific advancement forward. But there are many inventions humanity could actually use, in a practical sense, that are also really cool and wouldn’t seem out of place in a science fiction movie…

10. An Accurate Breathalyzer-Type Device To Know If Someone Is High On Marijuana

Today, law enforcement everywhere has a difficult task on their hands when it comes to the roadways. They have to not only deal with drunk drivers, but drivers who are high on heroin, meth, and now (legally in many states) marijuana. And this raises a really difficult question for the police: How do you know if a driver is under the influence of marijuana, in a way that wouldn’t be instantly thrown out in any court of law in the country? The roadways need to be safe, but it’s no use prosecuting someone if you don’t have evidence that will hold up.

Now, a small startup does have a device they are testing with law enforcement that can also test for alcohol as well, but it’s limited. The device can only tell if you’ve smoked within the last two hours. This isn’t exactly the futuristic level we were talking about, but it likely would be a lot of help, and may be enough to keep the roads safe for the time being. While some people may dispute that they would be safe to drive sooner, two hours is a pretty reasonable window of time, especially for state regulation.

9. Home Security Systems That Use Carefully Targeted Infrasound To Scare Off Intruders

Today, we have a lot of state-of-the-art security systems but most of them are just concerned with motion detection, cameras, making loud noises, and so forth. And, of course, all of them alert law enforcement. However, some have already considered the use of infrasound detection in order to help find intruders, and with that in mind, infrasound could help us in an entirely different way. Instead of guard dogs, actual guards, or weapons and the legal liability they can involve, if infrasound could be properly weaponized you could essentially scare people off your property.

Infrasound, often known as the “fear frequency,” usually stirs up the fight or flight feeling in people, and in the absence of anything to fight, most people just…run. A properly designed passive system that could detect and target intruders could theoretically use inaudible sound in order to keep your property safe and secure - almost like a magical spell that deters intruders. And as we know, it doesn’t get much more futuristic than something your enemies cannot distinguish from magic. Infrasonic detection could snuff out intruders quietly and alert the police if needed, but the active component would likely scare them off before they even broke a window or got up to any other shenanigans. It might even help deter teenage vandals from your property or, to put it another way: it might finally get those young punks to stay the heck off your lawn.

8. The James Bond “Fingerprint” Gun, For Which Only A Partial Prototype Exists

In the recent James Bond movies with Daniel Craig, Q gives Bond a special gun that can’t be fired without his handprint. Now, while there isn’t anything like this in real life, a German company did try to make a prototype. However, it involved a separate watch and the whole thing was all rather cumbersome. This technology, if it could actually be implemented in a way that truly worked well on a consistent basis and didn’t require any extra components, could revolutionize gun safety in the modern world, and especially in America.

Of course someone looking to hurt people could still use their gun to do so, but they couldn’t use their dad’s gun, a friend’s gun, and so on. And, a huge amount of gun deaths are tragically accidental, like when a kid gets his hands on a parent’s gun and, sadly, it goes off. Technology like this would keep your firearm from being used against you by someone who took it, and avoid horrible accidents that would scar you for life and destroy your family and relationships.

7. An Exercise Bike - Or Bike Switching Station - That Powers A Home Generator As You Use It

At the moment, this is the stuff of fantasy because of the amount of power it would (or more to the point, wouldn’t) generate. A bike-powered generator could fuel, say, lights for a little bit…and that’s about it. Some people have done the math and it really doesn’t sound like much. However, our imaginations have always wondered about how much power we could get from our own work, and many of us think of hand crank emergency radios as a good analogy. Still, those don’t use very much power at all, and that’s the real problem. While powering some lights is within the realm of reason, the biggest reason people want electricity after a disaster is heating and cooling.

Those things require a much more significant amount of power, and thus it’s quite difficult to actually get enough to make a real difference, or do anything for any significant amount of time. The amount of effort, in comparison to what you actually get in terms of cooling, or heating, might not be worth it. If a bike with enough gears and an efficient enough system was created so that a small family could, at least, generate enough power to keep themselves warm, or cool, as needed, it would be an incredible help in any kind of big disaster.

6. Ferromagnetic Roadways And Walkways For Practical Hover-Vehicle Technology

Not long ago, people saw the demo of the Hendo Hoverboards and got very excited…only to quickly crash back down to earth. The Hendo Hoverboard could hold several hours worth of charge, and really and truly hovered above the ground. It was a dream come true to many (especially those of us who have been waiting for Hoverboards since Back to the Future II), until the realities of the project hit. Now, it was a genius bit of engineering and did use some clever new techniques, but it was basically maglev technology, which requires a surface with metals that interact with magnets to actually do anything at all. In other words, unless it was on top of the right metal surface, it was just a big hunk of expensive junk you could stand on. This meant you could use it nowhere other than places specially constructed its their use.

However, if we had ferromagnetic roadways, we could have hoverboards, hover cars, and other hover technology. With the precision of maglev technology, we could likely cut down greatly on accidents while increasing our overall speed and efficiency at the same time, which is a big win-win. Of course, this would be ludicrously expensive, but in the long term, if built right, it would probably also last a lot longer than our current roadways.

5. Researchers Are Looking Into Ways To Use Our Own Body Heat To Charge Our Phones

Several years ago, people latched onto an article about some very experimental ideas to use a small device in your pocket to generate energy from your body heat, and some magazines started wildly speculating that you would have body heat-powered smartphones before you knew it. However, several years of fast-moving technology later, we really aren’t any closer on that front. The good news is, researchers are looking into it now for real, and not just looking at something that theoretically could get there for unrelated reasons.

If something like this could be designed, it could at least help with supplementary power. It’s possible it would only be enough to slow down the battery degradation, and not charge it enough to go much farther, but with battery technology bottlenecked every little bit could help. This would allow us to push our phones just a little bit further without resorting to bulky and cumbersome backup batteries and the like.

4. If We Could Create A Truly Energy-Efficient World, Much Fossil Fuel Use Would Be Eliminated

Today, there’s an incredible amount of energy used that is simply untapped. This source is motion, in general. Whenever something is moving, a certain amount of force is used. Some of that energy is transferred (energy, as we know, cannot be created or destroyed). If we could truly harness all kinetic energy from movement, especially all of our movement throughout the day, and not waste any energy potential around us, we could greatly cut down on our reliance on fossil fuel and other energy sources.

One company that found its way onto Shark Tank called Tremont Electronics designed a special device that could help charge a smartphone while you walk. They are working on other smaller products, but are also thinking big. They hope to one day secure the funding to test their technology to make “wave farms,” where energy is generated by using the motion from… well, waves. That was probably obvious. With this kind of technology, we could take green energy to an entirely new level most people never before imagined.

3. Affordable Water Filtration Infrastructure That Removes Pharmaceuticals And The Like

Today, the water infrastructure of some of the biggest countries - including the United States - has some huge deficiencies. And we aren’t even talking about places like Flint. But a huge amount of pharmaceutical byproducts are ending up in the water supply. Unfortunately, many water filtration plants are not properly equipped to clean this stuff out of the water. Even those sites that can get most of it out often only boast success rates of about 95%, which doesn’t sound so great when you realize the other 5% or so is pharmaceutical byproducts in your water.

To make matters worse, the FDA doesn’t really even have proper guidelines for this yet in the USA, and there really isn’t a standardized technology, much less a standardized system or set of methods get water to a safe level across the country. Part of the problem is people aren’t even sure what a safe level is with some of this stuff, as hormones have even ended up in the water can have effects in incredibly low concentrations, which we don’t even fully understand yet. If someone could invent a filtration method that could get this stuff out entirely (or, at least, almost entirely), and get water to a safe level - that could be easily implemented across the country - it would be an incredible help to humanity.

2. Sound Technology That Allows You To Filter And Hear Only What You Want To Hear

Hearing aids allow deaf people, or those hard of hearing, to hear. There are now special prototype speakers out there that can direct sound to an almost pinpoint degree, to the point where it will only be heard in one small location. Now, the second technology is fairly new and experimental, but with a little tweaking the two could be combined into an incredible invention. If you could truly direct sound accurately enough, you could make a device you could fit in your ear that could block out everything except for the sounds you did want to hear.

Imagine having a device where you could tell it to listen only to the TV in front of you, and not anything else that might be going on in the background. You could also use it to pay better attention to a conversation without worrying about background noise, or just shut out people or things that are bothering you in your environment. Let’s face it: All of us need our peace and quiet sometimes, and almost everyone would use this.

1. Even In The Year 2018, In The Fanciest Cars, You Won’t Find A Truly Accurate Gas Gauge

It’s fairly amazing to think that, even in the year 2018 - when most vehicles now are decked out with all of the most ridiculous new gauges and sensors and features - the one thing that’s stayed pretty much the same is the gas gauge. It still operates on the same principle with the floater mechanism where, on inclines, you may think you have more (or less) gas than you really do, and overall even when you think it’s full, it often really isn’t.

The truth is your gas gauge is actually designed to lie to you, mainly because car manufacturers think you enjoy the crazy game of trying to figure out how much gas you have left at any given time, and like going for broke - psychologically speaking. They also like to give you the false sense of security you get when you think it’s full when it really isn’t. Apparently, people really enjoy that feeling and don’t like how quickly the full meter would truly go away. Now, we believe that in 2018 people are grown up enough to accept the truth and enjoy the convenience of a truly accurate gas meter. It would lead to fewer people being stranded on the road, as they’d know the exact percentage at any given time - if this theoretical design was done right - and it would just be a great convenience for everyone in general.

Top image credit: sujins/Pixabay.

[Source: Toptenz.]

10 LIGHTS THAT HAVE PUZZLED SCIENCE

10 Lights That Have Puzzled Science
By Dawn Via, Listverse, 13 October 2018.

When you think of strange light phenomena, the first things that likely come to mind are rainbows, aurora borealis, or halos around the Sun. While at any given moment, you’re probably not going to look outside and see any of these things, there are other events that have dumbfounded people for years.

Our world has played host to a wide array of optical oddities. The origins of these strange lights aren’t immediately apparent, and they have both spawned legends and brought scientific inquiry. Explanations have been given for some; others remain not very well-understood.

10. Sprites, Jets, And Elves (Oh My!)

Photo credit: University of Alaska Fairbanks

While these oddities are more easily seen with a low-light camera, it is possible to see red sprites in the atmosphere with the naked eye. Jets are blue in color and can often look like lightning shooting upward from a cloud.^[1] Elves, the singular of which is “elve,” are flattened phenomena seen above thunderstorms and are also usually reddish in color.

These three hard-to-catch happenings are all examples of upper atmospheric lightning. Many times, they are found while looking for something else, such as meteor showers. As technology gets better, scientists are finding that there is a myriad of different kinds of atmospheric phenomena.

9. Hessdalen Lights

Photo credit: Mary Evans

These lights call the Hessdalen Valley in Norway their home. There has yet to be a distinct explanation for these lights, which range in color, strength, and length of occurrence. Many organizations, including UFO-Norge, a Norwegian organization, have taken interest in the lights, with limited results.

The event happens very low in the atmosphere, which makes it different from many other occurrences, which happen more frequently the higher you go. It appears in a doublet formation with surprising consistency and predictability.

A report completed in 2007 reveals a better hypothesis using cameras and intensity plots. This technology was necessary for this report due to the ease of mixing up lights from human sources and the Hessdalen lights themselves. The plots tell little of what the lights actually contain but point to one culprit: gas and dust. The dust floats up to meet the gas(es), which then combust until the fuel between the two is burned out.^[2]

8. Marfa Ghost Lights

Photo credit: Jody Wissing

As the name suggests, these lights are found near Marfa, Texas. The inhabitants of Marfa, having grown accustomed to these little guys, can attest that this is a friendly ghost light. They can be seen day or night, though the area, optimized for tourists since 2003, has a limited viewing time for visitors. These lights have been sighted since cowboys herded cattle on the prairies.^[3]

Skeptics suggest that the lights are caused by headlights from the nearby highway or campfires at night. Others believe it is an effect caused by the fluctuating temperatures due to Marfa being 1,429 meters (4,688 ft) above sea level. The warm and cold air refracts the light from sources in a way that’s not possible to see up close.

7. Ozark Spook Light

Photo credit: Legends of America

This shy guy calls Oklahoma its home. Due to it being easier to see from the east, it has also been given the name the Hornet Spook Light after the nearby town of Hornet, Missouri. This ball of curiosity varies in size but is almost always an orange color. No one has been able to decisively pinpoint the origin of this will-o’-the-wisp, despite it having been seen for hundreds of years, dating back to the Native Americans walking the Trail of Tears.

Explanations for this light are similar to that of the Marfa Ghost Lights - cars, billboards, or gaseous leakage. The legends around it often involve someone losing something and searching in the dark for it with their lantern. Another involves two lovers who eloped and were caught by a hunting party. The two leaped to their deaths into the Spring River, and their spirits float together ever since.^[4]

6. Brown Mountain Lights

Photo credit: Charles Braswell Jr.

There are many viewpoints to observe these lights in North Carolina. When first investigated, it was thought that they were nothing but headlights in the distance being refracted through the atmosphere. This common explanation for these occurrences was later thought to be disproved when the lights persisted after a flood, and there was no traffic (and no boats).

Other skeptics have found that there are actually two different phenomena that occur at the different viewing points. From Wiseman’s View, it appeared as though there were lights under the trees in the Brown Mountains, as if there were people waving lights around themselves. A Cherokee tale tells of the ghosts of wives looking for their husbands who were lost in war. These lights take a back seat to what others believe are the real Brown Mountain Lights.

The Brown Mountain Lights are in the sky, not the trees. It was first thought that a locomotive over the hill was casting its lights over the mountain, which would explain why locals would see the light at the same time every night (as long as the train ran on time). The model of train in question, however, had two lights, not one. It was later found that written reports of the lights came around the time electric lights were placed in the area. The lights being refracted into the sky were visible if viewed from a specific point, which is why they would linger and disappear. If one walked up the path too far, all they would have to do is walk back down to see the light again.^[5]

5. Chaleur Fire Ship

Photo credit: The Big Study

Legend has it that this is the ghost of a pirate ship that was destroyed for kidnapping two Native American girls. The blazing apparition travels through Canada’s Chaleur Bay, the host of the unfortunate event. The crew can still be seen operating the ship, raising and lowering sails. Science claims that this occurs because of natural gases beneath the waves, but the locals will tell you this has been happening ever since Captain Craig’s ship sank.

Science doesn’t have a good grasp on this one. Some have sailed out to the phenomenon, only to find it keeps the same distance no matter how far out they go. A telescope renders no details that you couldn’t just see by looking at it. There’s no solid state of the ship. Sometimes it lingers; other times, it appears and disappears just as fast.

Other theories are gases released by submarines, or bioluminescent life. The latter has been frowned upon by scientists because the Fire Ship still occurs even in winter, when the water is frozen.^[6]

4. Fata Morgana

Photo credit: Modiddy

Seen typically over water, these grand masters of trickery can confuse and stupefy. Experienced seagoers are able to see through their façade, though. The explanation for these is images on the water being refracted, flipped upside down, and stretched like rubber bands. These images can be in the shape of ships or pieces of land.

Fata Morganas can also occur on land. Essentially, an image is refracted from past the horizon into our eye’s view, causing things to appear where they should not be. Fata Morganas are thought to be the modern-day explanation for the legend of the Flying Dutchman, a ship over the horizon being cast into the view of another vessel, making it appear to not touch the water.^[7]

3. Green Flash

Photo credit: Brocken Inaglory

This event is possible to see if you have the right timing when the Sun rises or sets. The Sun will appear to have a small green rim around it, and through the effects of stretching that happens similarly with Fata Morganas, you can spot this green flash above the Sun.

This is most easily seen if you’re viewing the Sun over the water in unpolluted air.^[8] Rarely, the flash appears blue instead of the more common green.

2. Sundog

Photo credit: Gopherboy6956

Also known, more accurately, as parhelia (singular “parhelion”), sundogs are similar to halos, though they make two crescents that are always to the left and right of the Sun. These crescents are positioned at a 22-degree angle from the Sun. This occurs due to ice crystals in the atmosphere refracting the Sun’s light at just the right angles.

An interesting event that involved a Sundog was when NASA’s Solar Dynamics Observatory (SDO) was launched. There was a sundog present that day, and it happened to be in the trajectory of the SDO. Not only did the SDO destroy the sundog, but it caused the ice crystals in the air to spin. This caused a blast of white light to follow the SDO as it rose. It took some time for the scientists to figure out this secondary light phenomenon.^[9]

1. Moonbows

Photo credit: Tillea

Similar to rainbows (or sunbows, as I now think of them), water must be present in the air for moonbows to be seen. The Moon must be at its fullest or near its fullest to cast enough light. Being low in the sky to light the water at is also a must.

Moonbows are more easily seen near waterfalls during a full Moon at dusk. Yes, it is possible to have a double moonbow.^[10]

Top image: Winter sun halo rainbow on a cold day with ice fog in Skiwelt, Tirol, Austria. Credit: Martin from Tyrol/Flickr.

[Source: Listverse. Top image added.]

11 MAGNIFICENT MIGRATORY BIRDS

11 magnificent migratory birds
By Noel Kirkpatrick, Mother Nature Network, 1 October 2018.

About 40 percent of the world's birds migrate in some fashion, whether it's a short flight to a warmer locale or a long and arduous trek. Like other animals that undertake migrations, birds travel to find places with more resources or when breeding requires it. Plenty of variables play a role in how and when birds decide to migrate, including the climate and the availability of food and other resources. Above all, it's a special balance for each species. As Cornell Lab of Ornithology explains, even hummingbirds can survive chilly temperatures provided there's enough food to go around.

Whether it's for their migratory treks - some of which are incredibly long - to their status as endangered species, these birds are special high-flyers.

1. Bar-tailed godwit (Limosa lapponica)

Photo: Onioram/Wikimedia Commons

Measuring at most some 16 inches (41 centimeters), the bar-tailed godwit (Limosa lapponica) is not a large bird, but this species under takes a very long flight. In fact, the migration of the bar-tailed godwit is the longest non-stop migration of any bird on the planet. A 2007 study published in Proceedings of Royal Society B tracked birds migrating from New Zealand to China's Yellow Sea, a distance of around 5,950 miles (9,575 kilometers) at its shortest distance. The birds, however, flew more 6,800 miles over the course of nine days without stopping, following a longer path. At least one of the birds then flew from China to Alaska; that bird then flew from Alaska back to New Zealand.

2. Whooping crane (Grus americana)

Photo: U.S. Department of Agriculture/Wikimedia Commons

This endangered bird is the tallest in North America, standing nearly 5 feet tall (1.5 meters). Though you might expect a taller bird like this to make a longer migration, the wild whooping crane population doesn't make a particularly long trek, but it is an important one. This population summers in Canada's Wood Buffalo National Park and travels south to Texas' Aransas National Wildlife Refuge for the winters, a journey of some 3,000 miles (4,800 kilometers).

Multiple reintroduction programs have attempted to establish populations in the continental U.S., with mixed success. These populations have at times been guided in their migrations by humans flying ultralight aircraft, but federal regulations have hampered these efforts. Now, a number of whooping crane populations spread throughout Texas, Florida Louisiana and other states are considered non-migratory, staying in these locales year-round.

3. Calliope hummingbird (Selasphorus calliope)

Photo: Kati Fleming/Wikimedia Commons

From the biggest to the smallest: The calliope humming bird is the smallest breeding bird in Canada and the U.S. at only about 3 inches (7 centimeters) long. These tiny hummingbirds make an impressive journey for their size, and that's not even for migrations. These birds breed high up, sometimes 4,000 and 11,000 feet (1,219 and 3,352 meters) high, often near mountains, while their nests are often about 40 feet from the ground.

According to the Cornell Lab of Ornithology, these hummingbirds travel some 5,000 miles (8,046 kilometers) round-trip every year, leaving central and southern British Columbia in the later summer to make their way south along the Pacific Coast and the American West to reach Mexico, where the entire population - an estimated 4.5 million - spends the winter.

4. Orange-bellied parrot (Neophema chrysogaster)

Photo: JJ Harrison/Wikimedia Commons

Only three parrot species migrate, but that number may soon become two. The orange-bellied parrot is a critically endangered migratory bird, with the International Union for Conservation of Nature (IUCN) estimating that there were just 14 birds living in the wild as of February 2017. Efforts are underway to save the species by breeding it in captivity.

These parrots don't travel far for their migration. They breed in South West Tasmania during the summer and fly over the Bass Strait to Australia, often settling in Victoria or South Australia in the winter, a distance of roughly 600 miles (966 kilometers).

5. Eurasian wryneck (Jynx torquilla)

Photo: Pierre Dalous/Wikimedia Commons

The Eurasian wryneck - it gets half of its name from the ability to turn its head 180 degrees - is a woodpecker, albeit one with a shorter bill than other woodpeckers. As a result, the wryneck often reuses the holes of true woodpeckers for nesting instead of making its own.

The Eurasian wryneck, as the other half of its name suggests, has a large range, stretching across Europe and Central Asia. It's also the only Old World woodpecker that undertakes a long-distance migration. The European population will winter south of the Sahara, across a band of African countries from Sierra Leone to Ethiopia, a flight of almost 4,000 miles (6,437 kilometers), depending on the bird's starting point and destination. The population in Central Asia migrates south to India, Thailand and even southern Japan. These flights can be as long as 3,000 miles, depending on the bird's points of departure and landing.

6. Northern harrier (Circus hudsonius)

Photo: Tom Koerner/USFWS/Wikimedia Commons

According to the Audubon Society's field guide, North America is home to only one species of harrier, and that's the northern harrier. This member of the hawk family has a large range that stretches from Alaska and some of the northernmost parts of Canada to the southern United States. While those populations in the southern U.S. tend to stay put - no reason to migrate when you're already in pretty consistent temperatures - the harriers that reside further north will fly as far as Venezuela and Colombia to winter, a trek of some 5,600 miles (9,012 kilometers) depending on where they begin their journey.

7. Sooty shearwater (Ardenna grisea)

Photo: marlin harms/Wikimedia Commons

This incredibly common seabird, the IUCN estimates a global population of around 20 million individuals, has a most uncommon migration length. According to a 2006 study published in the journal PNAS, or Proceedings of the National Academy of Sciences of the United States of America, the birds fly almost 40,000 miles (64,000 kilometers) over the course of 200 days.

The sooty shearwaters in the study left New Zealand during autumn in the Southern Hemisphere and flew to the North Pacific in the Northern Hemisphere. Birds would settle in Japan, the Aleutian Islands or California. On the way back to New Zealand, some of the birds stopped by Chile.

8. Northern wheatear (Oenanthe oenanthe)

Photo: Zeynel Cebeci/Wikimedia Commons

The northern wheatear, like a few of the birds on this list, has a sizable range. They breed all across Eurasia and along both of North America's northern coasts. When it comes time to fly south for winter, the northern wheatear, regardless of their original starting point, heads for sub-Sahara Africa. In many cases, this flight involves traveling over oceans and ice, not exactly environments you expect to see songbirds.

These birds all take different routes to reach their destinations. "From the eastern arctic of Canada, wheatears traveled through Greenland to northwestern Europe before flying south to western Africa," the Cornell Lab of Ornithology writes. "Their western Arctic compatriots went the other way around the globe: they flew westward to Siberia and then diagonally across Asia to wind up in eastern Africa.

The birds that start from Alaska make a 9,320-mile (15,000 kilometer) trek just to get to Africa. When the wintering season is over, they do it all over again to get back.

9. Baer's pochard (Aythya baeri)

Photo: DickDaniels/Wikimedia Commons

Baer's pochard breeds mostly in eastern Russia and northwestern China, though there are reports of them breeding in Mongolia and North Korea as well. Once winter settles in these regions, these ducks head south, flocking to eastern and southern China, northeastern India, Thailand and Myanmar.

These aren't particularly long journeys, but they are journeys that may stop soon. Baer's pochard is a critically endangered bird, with an estimated population between 150 and 700 mature individuals. The birds seem most vulnerable during winter, and that's because of hunters. Additionally, the loss of wetlands in their breeding grounds has also contributed to their decline.

10. Snowy owl (Bubo scandiacus)

Photo: Bert de Tilly/Wikimedia Commons

The migratory habits of snowy owls are a bit of a mystery to us. They fly south when winter arrives in their northern Canadian and Arctic habitats, but sometimes they go far south - like, really far south. During the 2013-2014 migration, snowy owls were reported in Massachusetts, Virginia, Arkansas, Florida and even Bermuda. In 2012, one was even spotted in Hawaii, presumably because it stowed away on a ship. Tagged birds demonstrate that despite their southern exposure, they still make their way back to the Arctic Circle.

Snowy owls are more nomadic than migratory, leaving their traditional stomping grounds to hunt for food, but a lack of a food doesn't always seem to be the reason they push so far south. The owls spotted during the 2013-2014 irruption, a term used for unusual bird migrations, were all reported as being healthy. In short, we know they do this, but we don't know why.

11. Arctic tern (Sterna paradisaea)

Photo: Ken Conger/National Park Service/Wikimedia Commons

If you're looking for a truly long flight, look no further than the migration of the Arctic tern. These small birds live in the Arctic Circle, but populations can be found in Massachusetts and England as well. The species has a convoluted and long trek to make it to breeding grounds along the Antarctic coast. Yes, that's right, the Arctic tern flies from the Arctic to the Antarctic every year. Round trip, the Arctic tern's flight covers 59,650 miles (95,997 kilometers), more than any other bird on the planet. (To put this flight in perspective, the Earth's circumference is only 24,901 miles.)

Top image: Birds fly in a group during sunset near the German nature reserve Alte Leine. Credit: Wernersen04/Wikimedia Commons.

[Source: Mother Nature Network.]