How Do Earthquake Early Warning Systems Work?

California plans a system that can detect earthquake waves to warn the public.

A public earthquake warning system could be used to reduce damages and injuries on services like BART commuter trains in California.

One minute you're sitting at your desk on solid ground, the next the floor slips out from underneath you and things start to rattle off the shelves.Earthquakes seem to come out of nowhere and can cause widespread devastation.

Windblown Dunes

Rippled, wind-blown sediments stretch across the Martian surface, as seen from NASA's Mars Reconnaissance Orbiter (MRO) on August 31.

Shaped by Martian weather over great periods of time, the light ripples of coarse stones crisscross dark sand dunes. Here, they can be seen filling in the upper stretch of the Valles Marineris, the Grand Canyon of Mars.

Desert Oasis

Resembling Braille letters, irrigated agricultural plots dot the Sahara in southeastern Libya. The view was captured by Japan's ALOS satellite and released on September 20.

Each plot is 0.6 mile (1 kilometer) wide. Between the city of Al Jawf, seen in the upper left of this image, and the circular plots are the two parallel runways of the local airport.

Flaming Horns

Are those devil's horns sprouting from the underside of the sun? Nope, this ultraviolet image snapped by NASA's STEREO space probe reveals twin arcs of super-heated gas, called solar prominences, flung into space by Sol on September 14.

Heated to thousands of degrees, these giant filaments of plasma are twisted into intricate ribbons by the powerful magnetic fields surrounding giant groups of sunspots.

Hokusai!

NASA's MESSENGER spacecraft snapped this close-up view of the 59-mile-wide (95-kilometer-wide) Hokusai crater on September 17, while orbiting Mercury.

Sporting grand central peaks and an extensive set of bright rays that extend for 600 miles (1,000 kilometers), Hokusai is believed to be one of the youngest impact sites on the solar system's innermost planet.

Cat's Paw Nebula

The Cat's Paw nebula, also known as NGC 6334, is one of the most prolific star factories in the Milky Way.

The newly installed ArTeMis camera on the APEX telescope delivers this stunning near-infrared view of NGC 6334, a swirling mix of gas and dust seen from Chile's Atacama Desert.

Located in the southern constellation Scorpius, the Cat's Paw lies some 5,500 light-years from Earth and spans 50 light-years across, covering the same amount of nighttime sky as the full moon.

After giving birth to tens of thousands of newborn stars over its lifetime, the nebula now swaddles and hides from view at least 2,000 young stars—newborns hidden amid clouds of dust grains seen shining in orange-brown hues—still waiting to emerge and drift away into space.

—Andrew Fazekas

UN Climate Report Relevance Debated Amid Rollout

Can a long-awaited international global warming report keep up with a fast-changing climate?

An iceberg tower in the Labrador Sea, Canada.

The long-awaited Intergovernmental Panel on Climate Change's (IPCC) first report in six years arrives this Friday, a high-profile summary of global warming's scientific status certain to influence attempts to address the threat of a warming world. It also faces criticism before it even gets out of the gate.

Water Wars: Egyptians Condemn Ethiopia's 

"Ethiopia is killing us," taxi driver Ahmed Hossam said, as he picked his way through Cairo's notoriously traffic-clogged streets. "If they build this dam, there will be no Nile. If there's no Nile, then there's no Egypt."

Marine Animals Keep Time With Multiple Clocks

From fungi to farm animals to humans, organisms across a broad spectrum experience daily cycles controlled by a circadian clock. This internal clock tells us when to sleep or rest, and when it's time to wake up.

But it turns out that some animals—and perhaps even humans—keep time with more than one kind of clock, new studies say.

How Genius Carl Haber Restores Long-Lost Sounds

Some historic sounds were lost—until the physicist began digitally restoring them.

Physicist Carl Haber shows recordings by Alexander Graham Bell at Volta Laboratory during a news conference at the Library of Congress in Washington in December 2011.

Does "Global Warming Pause" Debate Miss Big Picture?

The Columbia Glacier in Alaska, seen in 2006 (top) and 2012 (bottom).

The United Nations' Intergovernmental Panel on Climate Change (IPCC) is meeting in Stockholm, Sweden, this week to iron out the final details of a widely anticipated report on the current state of global warming science. There has been much speculation about how the report will address an apparent decrease in the rate of warming over the past few years, dubbed a "global warming pause."

MacArthur Genius: "Plants Have Souls"

C. Kevin Boyce is a paleobotanist—and a recepient of the 2013 MacArthur "genius grant."

Scientists Unravel Secrets of Monster Black Hole at Center of Milky Way

Two million years ago, the supermassive black hole at the center of our galaxy was 100 million times more powerful than it is today.

For years astronomers have been puzzled as to why our Milky Way galaxy's "volcano"—a supermassive black hole (SMBH) at its core—is dormant today.

Solar System Spaceal Mention: Ring of Fire

This spectacular composite photo of the May 9 annular solar eclipse above Western Australia brilliantly shows the progress of the moon's shadow as it crosses the disk of the sun. The passage produces the famous "ring of fire" effect seen in such events, where the width of the moon as seen from Earth doesn't completely cover the sun during an otherwise total eclipse.

Young Astronomy Photographer Winner: Milky Way

Dusky brown dust lanes cross the star-studded core of our Milky Way galaxy in this mesmerizing portrait taken on July 15, 2012, by 14-year-old Jacob Marchio from the USA.

In this breathtaking cosmic vista, the central bulge of the Milky Way—obscured by the dark rifts of dust seen here—is located some 26,000 light-years from Earth. Dominating the foreground of the picture is a rich star-field home to countless nebulae and star clusters scattered through the plane of our galaxy.

Earth and Space Special Mention: Perseid Burst

A magnificent cosmic burst of meteors is captured in this composite image from south-central Wyoming's Medicine Bow National Forest in August 2012, during the peak of the Perseid shower.

Astrophotographer David Kingham managed to capture nature's best fireworks show by collecting 23 individual 30-second-long exposures, all of them taken over the seven hours of a single night session.

Solar System Runner-Up: Magnetic Maelstrom

Islands of sunspots—each one bigger in size than Earth—appear to float in a sea of hot plasma on the sun's surface, in this dramatically detailed image captured on July 11, 2012.

Robotic Scope Winner: Orion in Bloom

The great stellar nursery known as the Orion nebula is captured in all its glory in this February 4, 2013, composite shot combining two telescope views.

By combining results from two different telescopes, a robotic one in Australia and another in Hungary, László Francsics managed to catch sight of tiny dark blobs of gas and dust surrounding newly formed stars in the nebula.

Known as protoplanetary disks, astronomers believe that these plates of material coalesce over time to form planets, moons, asteroids, and comets.

Earth and Space Runner-Up: Green Energy

A glowing green vortex-shaped aurora lights up the snowy mountains near Grøtfjord in Norway on March 20, 2013.

As clouds of charged particles fling themselves off the sun and hit Earth's protective magnetic field, geomagnetic storms can form near the poles of our planet, generating glowing sheets and aurora curtains in the upper atmosphere.

Solar System Winner: Australian Totality

The scorching hot outer atmosphere of the sun—known as the corona—pops into view solely during the fleeting moments of a solar eclipse, as seen here in this award-winning composite photo taken in Australia during the totality on November 14, 2012.

The above image is a combination of 81 individual exposures. They have been digitally stacked together and enhanced to bring out the solar corona's filaments and waves, which resemble ghostly tentacles reaching out into the overhead sky.

Our People and Space Winner: Moon Silhouettes

The silhouettes of onlookers stand framed in front of the yellow glow of the rising full moon on March 28, 2013, as seen from Mount Victoria Lookout in Wellington, New Zealand.

A rising or setting full moon regularly appears to change its familiar silvery color to a more yellow-orange hue due to its light refracting off countless  dust particles in Earth's atmosphere.

Deep Space Winner: Celestial Impasto

Like a painting filled with delicate brushstrokes, the giant star-forming nebula Sh2-239 lights up the celestial canvas in this Deep Space category award-winning image.

Sitting only 453 light-years from Earth in the constellation Taurus, Sh2-239 is one of the nearest stellar factories to Earth.

Overall Winner: Guiding Light to the Stars

A lighthouse beacon stands guard beneath the star-studded Milky Way arching over New Zealand's Cape Palliser coastline, as seen in this overall winning photograph from the Royal Observatory's 2013 Astronomy Photographer of the Year competition.

How Did the Pakistan Earthquake Create a Mud Island?

A mud volcano is thought to be behind new landmass.

On Tuesday, a 7.7-magnitude earthquake struck a remote part of western Pakistan, killing more than 260 people and displacing hundreds of thousands. It also triggered formation of a new island off the coast, which has quickly become a global curiosity.

Fish Fossil Has Oldest Known Face, May Influence Evolution

The 419-million-year-old fossil has the same jawbones as vertebrates.

Is this the first face? The extinct fish swims in ancient seas in an illustration.

Scientists have found the oldest face—and it's a fish. (Not a fishface, though.)

The 419-million-year-old fish fossil could help explain when and how vertebrates, including humans, acquired our faces—suggesting a far more primitive origin for this critical feature of our success, a new study says.

"Entelognathus primordialis is one of the earliest, and certainly the most primitive, fossil fish that has the same jawbones as modern bony fishes and land vertebrates including ourselves," said study co-author Min Zhu of the Chinese Academy of Sciences in Beijing.

"The human jaw is quite directly connected to the jaw of this fish, and that's what makes it so interesting."

The bones comprising the fish's cheek and jaws appear essentially the same as those found in modern bony vertebrates, including humans, Zhu added. Because it boasts maxilla and mandible much like our own, the fish may be the earliest known creature with what we'd recognize as a face. (Related: "Ancient Toothy Fish Found in Arctic—Giant Prowled Rivers.")

City of the Gods, Giza Plateau

The Great Pyramid of Giza is the only wonder of the ancient world still standing. In addition to being an architectural marvel, some believe that beneath the Giza Plateau exists something almost as extraordinary: a massive series of underground tunnels and chambers.

Beginning in 1978, researchers began to map out a massive underground complex that they referred to as a potential “metropolis.” Known as the City of the Gods, it is still shrouded in mystery. Considering this vast underground city is directly beneath one of the most important historical structures in the world, it is not likely that its mysteries will be easily unlocked for the foreseeable future. Furthermore, many vocal opponents to the theory of the City of the Gods claim that they don’t exist and are a pseudoscientific idea invented to support the notion of alien gods.

THE UNDERGROUND APARTMENT

Cappadocia, Turkey

The area of Cappadocia, Turkey, has become famous for its underground cities—most notably the underground city of Derinkuyu. It consisted of seven underground levels and is said to have housed residents in the thousands. This was not a small city and it was not a series of small cave homes either. Throughout Derinkuyu were shops and churches, areas in which the residents produced wine, and even schools. The underground cities are believed to have been hiding places for Christians avoiding persecution from the Roman Empire, because no one likes being fed to lions.

Merging Vehicles And Humans

This project, dubbed Homunculus, seems a little silly on the surface. However, it’s also one of the first experiments of its kind to attempt to merge a human with a vehicle, and the implications could potentially change the way we communicate with our cars. As the researchers put it, “We propose the situation that humans and vehicles can be unified as one unit.”

The current approach with Homunculus is geared toward pedestrian safety. For example, an onboard camera tracks the driver’s head movements, while a pair of eyes attached to the front of the car copies those movements. This allows a pedestrian to see if the driver is looking at them. Strips of infrared sensors on the sides of the car connect to two vibrating motors on the driver’s arms, signaling when something (a small child, for instance) is close to the car.

Fully Articulated Prosthetics

Perhaps the oldest form of cyborg technology is the prosthetic limb. We know that the ancient Egyptians used prosthetics, but we’ve come a long way from carving blocks of wood into the shape of a toe. In fact, we’ve made more progress in that area in the past decade or so than the rest of history combined. Take the BeBionic myoelectric prosthetic hand, which can move every finger joint individually via a connection to the skin and muscles in the amputee’s upper arm. A tiny twitch will orient the hand into a different position based on the electrical current running through the skin—giving the prosthetic full articulation that’s almost, but not quite, as realistic as using a real hand.

It takes a little practice, but eventually you can perform a huge number of tasks that wouldn’t be possible with a less advanced prosthetic, such as tying your shoelaces or using a computer mouse.

Brainwave Sensors

We’ve already discussed the huge strides in reading brainwaves, like one experiment in which researchers flew a helicopter with brain signals picked up by an EEG sensor.

But using a different type of brainwave reader—known as functional near-infrared spectroscopy, or fNIRS—a group of researchers at Tufts University has developed a device that will not only pick up brainwaves, but actually organizes that data to tap into personal preferences. In this case, the fNIRS data was linked to a brain-computer interface that was able to accurately display movie recommendations. Stranger yet, the more a person used the system, the more accurate the predictions became, as if it was actually learning about that person over time.

These sensors are difficult to use in everyday settings because little things like head movements can disrupt the signal, but the same team is developing a program that can effectively filter out this noise. This could lead to a seamless brain-to-machine connection that will be able to make the perfect decision for you every time. It could tell you what movie you want to watch, what you want to eat, or even what kind of car you want to buy.

Vibrotactile Gloves

One of the attractions of becoming a cyborg is the possibility of extra senses. Humans have five senses (depending on how you divide them up), and most of them are linked to a specific organ. For example, you see with your eyes. But what if you had the ability to “see” with your hands when conditions weren’t the best for vision? Well, ask Anthony Carton and Lucy Dunne of the University of Minnesota, who are developing technology that will help firefighters navigate through smoke without needing to actually see.

It’s called the vibrotactile glove, and it uses a pair of gloves outfitted with an ultrasonic rangefinder. Inside the glove is a series of vibrating motors that, when activated by the rangefinder, will map the position of surrounding obstacles on the back of the wearer’s hand. A firefighter will be able to hold his hand in front of him and “feel” the position of everything in the room.

AWESOME TECH!!!!

Display-Enhanced Forearm

The area between a person’s wrist and elbow serves a very important function. Specifically, it keeps your wrist connected to your elbow. But to Simon Oberding and his team at Singapore University, that area is nothing more than wasted space. What Oberding plans to do with the forearms of the future is turn them into digital displays. He’s developed a prototype that straps onto the forearm and has four separate screens, each of which shows a different set of data. For example, one screen can display GPS directions while another scans YouTube for interesting videos.

At its core, Oberding’s prototype is just an extended wristwatch. To reach true cyborg level, you have to dig a little deeper and implant the watch directly under your skin. A Toronto software company—called AutoDesk—has been experimenting with implanted user interfaces. They don’t have a specific goal for the technology yet, but they’ve managed to successfully implant a touch sensor in the forearm of a cadaver and charge the embedded electronics with a Bluetooth receiver. They are still working on making the tech commercially viable.

Sustainable Fusion Reactor

Nuclear fission (the process by which nuclear power plants produce energy) is much easier to control than nuclear fusion (the process by which the sun burns, and nuclear weapons work). Small nuclear fusion reactors have been built, but a large-scale, sustainable fusion reactor has yet to be attempted—until now. A consortium of seven member bodies (the US, EU, Russia, China, Japan, South Korea, and India) has chosen a location in France to build the world’s first. And while even its champions concede it could be decades before it’s dispensing energy, nuclear fusion is cleaner and yields three to four times more power than fission.

The project is called ITER, for International Thermonuclear Experimental Reactor, and it is the second-largest cooperative international scientific endeavor (ranking behind only the Space Station). It will use a donut-shaped magnetic field to contain gases that will reach temperatures comparable to those at the core of the sun, in excess of 150 million degrees C (270 million F), and will produce 10 times more power than it consumes.

Ultra–High Speed Tube Trains

Magnetic levitation, or Maglev, trains have been in development for quite some time. In Japan, a recent successful test run means that plans are underway to connect the whole country by 2045 with trains capable of reaching over 480 kph (300 mph). They accomplish this by removing the wheels—and thereby, contact and friction—from the equation. Maglev trains levitate above the track, suspended by an electromagnetic field. And while the Japanese model is impressive, one company in the small Colorado town of Longmont is upping the ante by eliminating another barrier to shattering speeds: namely, wind resistance.

To be fair, eliminating this factor doesn’t so much up the ante as it blows up the entire house containing the card table. Daryl Oster of ET3 says that his company’s concept, called the Evacuated Tube Transport, is the future of transportation, and it very well may be. Its track is contained within a sealed, pressurized vacuum tube, making the capsules conceivably capable of speeds up 6,500 kph (4,000 mph), all while subjecting the passenger to G-forces comparable to that of a leisurely ride on the highway and transporting them across the entire US in less than an hour. ET3 has built prototype capsules and, as of this writing, are searching for an appropriate stretch to build the first tube.

Wireless Electricity

The notion of wireless electric power has been around far longer than one might think: Nikola Tesla might have perfected the technology a century ago if he had not been poor, unlucky, and kind of crazy. Many today are unaware that, even though it has obviously yet to be deployed en masse, wireless power transfer actually exists.

Wireless device charging has been around for some time, and continues to improve. Companies like Witricity are at work developing electric “hubs” that can power your entire house. Their prototype is called “Prodigy” and is based on research done by physicist Marin Soljacic of MIT. It works by exploiting the fact that certain frequencies of electromagnetic waves facilitate ease of energy transfer, and two objects resonating with such a frequency can easily transfer electricity between them, even at some distance and even if the objects are metal. When perfected (which many see coming within the next decade), it could bring about an end to batteries as we know them.

Paper-Thin, Flexible Computers and Phones

In early 2013, consumer electronics shows debuted a prototype by European firm Plastic Logic of a product called the Papertab. That would be a portmanteau of “paper” and “tablet” and it is pretty much what it sounds like: a fully functional, touch screen tablet computer that is not only as thin as a sheet of paper, but as flexible as one too, and possesses the same reflective qualities. The company envisions such machines being ubiquitous within five to 10 years, as they could be inexpensive and interactive. A consumer could have several lying around, multi-tasking with different media all in service of one project.

A joint project between two American and Canadian universities has been creatively dubbed the Paperphone. Queens University director Dr. Roel Vertegaal has largely the same vision of the project. “This is the future,” he says. “Everything is going to look and feel like this within five years.” The machine is the size of a regular smartphone, with a 9.4-centimeter (3.7 in) display, but again, paper-thin and flexible. Users can give the phone commands by using “bend gestures.” It consumes no power when not in use and is considerably harder to damage than an ordinary phone.

Artificial Gills

Inventors have long sought an underwater breathing apparatus that doesn’t store oxygen, but extracts it from the water the way gills do. Israeli inventor Alon Bodner has come close.

The device, aptly named LikeAFish, works by using a centrifuge to lower the pressure of water within an airtight chamber. Since only a little oxygen is contained in water, the device must move about 190 liters (50 gallons) per minute in order for the average person to breathe comfortably. Despite this, the only real barrier to implementation is size and weight, but it’s close enough that the device has been under consideration for military use for several years now.

Such a system would obviously allow for longer “bottom time” without the need for refilling oxygen and would decrease the amount of nitrogen the diver is exposed to. According to Bodner’s website, the company spent 2012 “quietly designing a prototype to be installed on board a naval submarine,” so they may be very close to solving the size and weight issues of previous prototypes.

Agricultural Robots

Agricultural robotics are, somewhat surprisingly, still in their infancy. While unemployment seems to be leveling off, there is still talk of a possible general labor shortage in the near future—particularly in agriculture. Many companies worldwide are attempting to bring various types of robot farmhands to market, but in robotics (where government and academic projects still lead the way) it tends to take longer than in some other, more commercial industries for such projects to obtain funding, produce a product, and prove its viability.

But the technology is coming along, and it’s easy to imagine it implemented on a wide-scale basis before too long. One Boston company that was able to raise nearly $8 billion in private funds in 2011 has developed a robot that it claims could perform 40 percent of the manual labor currently performed on farms. A Japanese research company has developed a robot that performs stereo imaging of strawberries to determine their ripeness before picking them, and MIT has a cherry tomato garden that is managed by a small crew of robots equipped with vision sensors. Of course, the main advantage to robot farm workers is the fact that they can work around the clock and never get tired.

Mongolia

Untamed Hovsgol

If you yearn for a connection to the wild, you will find it here. Hovsgol is the northernmost of Mongolia’s 21 provinces, shadowing Russia’s border and sharing the great Siberian taiga (subarctic coniferous forest). Lichens in bright greens and oranges color 10,000-foot passes, while sacred rivers, rumored to never freeze, feed lakes framed by snow-tipped mountains.

Hovsgol is just now opening its arms to travelers who come to catch and release taimen, giant salmonid “river wolves” that stalk Hovsgol’s waterways. Others come to ride Mongolian ponies in search of the Tsaatan, small bands of nomadic reindeer herders (above) who live in encampments and follow shamanistic beliefs.

Pittsburgh

Extreme Metropolitan Makeover

Three rivers. One reinvented city. On all counts, the Steel City’s transformation over the past quarter century qualifies as revolutionary. Its mourning for its industrial past long concluded, this western Pennsylvania city changed jobs and reclaimed its major assets: a natural setting that rivals Lisbon and San Francisco, a wealth of fine art and architecture, and a quirky sense of humor.

Pittsburgh’s century-wide swath of architectural styles persuaded British film director Christopher Nolan to use downtown as a stand-in for Gotham City in this summer’s Dark Knight Rises. Sustainable design has transformed Victorian landmarks like the glass-domed Phipps Conservatory and created contemporary ones like the swooping waterfront convention center 

New Zealand

Cyclists' Bliss

A violent struggle created this world, according to Maori mythology: Indigenous New Zealanders say Sky Father and Earth Mother were ripped from each other’s arms to make room for mountains, forests, and oceans. Around Rotorua, a Maori heartland and home of the mineral-rimmed Champagne Pool (above), it’s easy to believe the struggle continues, as the eerie landscape bubbles and churns like some primordial stew. Geysers erupt, mud boils, and steam seeps from cliffs and sidewalks, leaving a sulfurous scent in the air.

In a land where adrenaline lovers ride rockets suspended on wires and roll downhill inside giant plastic balls, biking seems one of the saner ways to plunge into a landscape that compels exploration: hot springs, glaciers, rain forests, and volcanoes, encircled by nearly 10,000 miles of coastline, packed into a country barely bigger than Colorado. New Zealand is made for journeys, physical and spiritual.

Belfast, Northern Ireland

A Capital City of Titanic Ambition

Finding yourself in the company of a chef from the R.M.S. Titanic is just one of the surprises that Belfast has to offer. "Barney" leads the Belfast Bred walking tour on an ingredient hunt, tracking the culinary heritage of the Northern Irish city that built the Titanic. The centennial of her maiden voyage—April 10, 2012—gives Barney the chance to share Belfast’s pride in the “floating palace” and show off a capital that is redefining itself in the eyes of the world.

Sections of the city have undergone regeneration since Belfast emerged from the Troubles, the three decades of violence that culminated in the Good Friday Agreement in 1998. The Titanic’s birthplace on the River Lagan is now called the Titanic Quarter (above). A $152.1-million attraction opens in April with audiovisual exhibits, underwater footage of the wreck, and a ride that re-creates a trip through the shipyards of 1911 to tell
the passenger liner’s story. 
The glossy venue overlooks the Harland and Wolff slipways where the Titanic set sail to Southampton to begin her fateful voyage to New York.

Greece

Ancient Beauty

Patrick Leigh Fermor, the dashing philhellene who died last June, knew that to get under Greece’s skin you must stray from the instant gratifications of its seaside resorts. Traveling on foot across the gorges of Roumeli and mountains of Mani, Leigh Fermor discovered a land of fierce beauty where traditions run deep. Eventually, he settled in Kardamíli, a sleepy hamlet in the southern Peloponnese, which he hoped was “too inaccessible, with too little to do, for it ever to be seriously endangered by tourism.”

Happily, he was right. While some islands have been scarred by unregulated development—and as the country grapples with the worst financial crisis in its modern history—Greece’s rugged mainland retains its unadulterated allure. Foraging for mushrooms in Epirus, watching pink pelicans take flight over Prespa Lake, listening to ethereal chanting in Meteora’s monasteries (such as the Roussanou Monastery, above)—there remain pockets of Greece where time stands still. You just have to know where to look.

Guatemala

Modern Maya World

Every year countless travelers visit the ruins of once great Maya cities: Chichén Itzá (Mexico), Tikal (Guatemala), Caracol (Belize), and Copán (Honduras). The pyramids and stelae are well worth seeing, especially at jungle-shrouded Tikal (above), but here’s the thing: Maya civilization isn’t long gone. Its apogee may have passed, but millions of Maya people and their culture remain alive and well, most vibrantly in Guatemala’s Western Highlands.

The most alluring place in Maya Guatemala is Chichicastenango, a walkable town about three hours by road from Guatemala City where more than 95 percent of the people are indigenous. Each Thursday and Sunday, Maya vendors carry their goods on their backs at dawn to Chichi’s market, selling brilliantly hued textiles, fearsome wooden masks, golden and purple maize, necklaces, and produce arranged in Escher-like patterns. Smoke from grills perfumes the narrow aisles, and so many women briskly pat stone-ground tortillas into shape that it sounds like a standing ovation.

London

Faster, Higher, Stronger

In Olympic-ready London, a new landmark (City Hall) meets old (Tower Bridge) along the Thames. The last time London hosted the Olympics, in 1948, locals subsisted on rations, there was no budget for new sports venues, and many competitors slept in military huts in Richmond Park. Britain may be entering another age of austerity, but nearly $15 billion has been spent on sprucing up the capital for the 2012 Olympics.

Many sporting events have already sold out, but there will be hundreds of free cultural events to enjoy throughout the summer. The London 2012 Festival will turn the whole country into a living stage, from a multilingual bonanza of Shakespeare productions at Stratford-upon-Avon to a soccer-inspired art installation deep in a Scottish forest. David Hockney, Leona Lewis, and Philip Glass are among the heavyweights headlining in London.

Oman

Perfumed Oasis

While neighboring oil-rich countries on the Arabian Peninsula are building skyscrapers and convention centers, Oman is erecting an opera house and planting desert gardens amid capital city Muscat’s white stone buildings. Sultan Qaboos sparked the country’s modern renaissance with his rise to power in 1970—adding scores of new schools and hospitals and increasing the miles of paved road from six to over 3,700.

Many of Oman’s delights cater to the elite luxury traveler. The ritziest hotel in Muscat offers a helicopter landing pad out back. Pleasure yachts anchor off the coast; it can be easy to forget the sea is Arabian, not Mediterranean. Muscat's Park Inn, pictured here, has a roof terrace view to rival any.