Tabla de contenidos para May-Jun-11 en Science Illustrated

Off the coast of Banks Island in the Canadian arctic, archaeologists have found the wreck of HMS Investigator, a British naval vessel abandoned at sea in 1853. Using sonar, a Canadian research team from Parks Canada found the wreck last summer in Mercy Bay, just east of the Beaufort Sea. The surprisingly intact hull lay on the bottom at a depth of about 36 feet. Most of the year, Mercy Bay is frozen over, and these frigid conditions may have helped to preserve the Investigator, in part because the cold, dark water is inhospitable to organisms that could degrade it. The ship, under the command of Captain Robert McClure, left England in 1850 to search for the Erebus and the Terror. The two vessels were carrying John Franklin's polar expedition,…

The winter of early 2010 was an unusually cold one for much of Europe. Cities across the continent experienced heavy snowfall and record low temperatures. Airports and train stations shut down and roads were closed, leaving thousands of travelers stranded, sometimes for days. Crops froze, threatening the region's food supply. Hundreds of people died from the freezing temperatures. Recent research suggests that magnetic activity on the sun might have been behind the cold snap. Some of the sun's effects on our planet—disruptions in telecommunications caused by solar flares, for example—are well known, but the mechanisms that connect sunspots and weather have only recently been elucidated. As researchers continue to investigate how solar activity affects conditions on Earth, they are expanding our understanding of the planet's climate. Like the Earth, the…

A man with a knife is chasing you. You're running as fast as you can, but he's getting closer. You try to speed up, but your legs won't respond. In a few seconds, he'll catch up and stab you to death. Then you wake up. The terrifying scenario was nothing more than a chase dream, one of the most common types of nightmares, and you were powerless as it unfolded. Unless you are a gamer. Recent research from Grant McEwan University in Alberta suggests that frequent videogame players are better able to escape from the man with the knife than those who don't play. This connection between gaming in the real world and controlling one's dream world could someday lead to therapies for debilitating nightmares such as those common among…

Don't have $200,000 for a ticket into space on a Virgin Galactic flight? That's OK. You can experience space exploration right here on Earth by visiting Kennedy Space Center in Florida, where the X-37B and NASA shuttles launch. Visitors can strap in on a six-story shuttle simulator to experience the sights, sounds and sensations of a real launch; tour the rockets used to carry the crafts into space; meet with astronauts; learn about the future of galactic exploration; and maybe even get to watch a launch. Merritt Island, Fla. All year Adults, $41; children (ages 3 through 11), $31. Each ticket is valid for two days of admission. Special tours and activities are available at extra cost; prices vary (kennedyspacecenter.com).…

For many, the word “forest” conjures up images of mountaintop pines and woodland creatures. But on tropical and subtropical coasts around the world, there are forests of a very different sort: mangroves. A diverse group of trees and large shrubs that sprout in salty tidal waters, mangroves and the forests they create are home not to chipmunks and bears but to fish and tigers. Mangroves are found in 123 countries and territories, but all together they cover an area about the size of Iowa. However small, the value of these ecosystems should not be underestimated. Mangroves shelter and feed countless species that live within them. Their rich stores of biomass nourish adjacent inland and offshore habitats and sequester carbon from the atmosphere at higher rates than most other ecosystems. Their…

1 Karen and John live in different houses on the same side of a street. The house numbers all have three digits, and even- and odd-numbered houses are on opposite sides of the street. Both Karen's house number and John's are squares, and each can be obtained from the other by reversing the order of the digits. What are their house numbers? 2 Put numbers in the figures so that each row, column and color contains all of the numbers from 1 through 4. 3 The letters below share a certain property. What is the only other capital letter with the same property? 4 Which figure comes next in the sequence? 5 A railway line contains a certain number of stations. At each station, you can buy a ticket to…

Q What is an aurora? A These multihued curtains of light appear in the sky when particles in the Earth's magnetic field, energized by solar wind, collide with atmospheric molecules. The phenomenon, also known as the Northern and Southern Lights, is named after Aurora, the Greco-Roman personification of dawn, whose appearance is thought to have resembled the reddish glow of the lights. The sun is constantly emitting energetic particles, which are then whisked through space in the form of solar wind. When the wind hits the Earth's magnetic field, some solar particles are absorbed and transfer their energy to any other particles already present in the magnetic field. Auroras appear most frequently over the Earth's poles, 60 and 70 degrees north and south latitude, where the magnetic field bends inward.…

The sun has a significant influence on the Earth's climate. But it's not the only thing climate researchers have to consider when constructing models. Several factors on Earth affect the climate as well: Masses of clouds increase the Earth's albedo, its ability to reflect sunlight back into space, and can cause cooling. Warm and cool water and, by extension, warm and cool air masses are transported around the globe, in part, by ocean currents. When eruptions shoot ash into the atmosphere, more sunlight is reflected back out into space, which briefly cools the planet. Soot and ash from factories can have the same effect as volcanic eruptions, but the greenhouse gases from man-made pollution cause temperatures to rise. Fields reflect more sunlight than forests, but forests absorb more carbon.…

It looked like just another routine launch when the giant Atlas rocket rose into the sky above Cape Canaveral in Florida last April. But its payload was new: On the launch rocket sat the latest American spaceplane design, the X-37B. The vehicle is the first unmanned reusable spacecraft built by the U.S. and is likely to be a prototype for the vehicles that will succeed the space shuttle after NASA retires it. Because it was a classified project operated by the U.S. Air Force, the exact path of X-37B's maiden flight was kept secret at launch. Specifics about the various technologies onboard also remained vague. For 224 days, a network of satellite trackers around the world scanned the night sky, watching as the plane shifted between different orbital paths. On…

Radiometric dating using carbon-14, a method typically used to determine the age of human artifacts, does not work on fossil bones more than 50,000 years old. The isotope almost completely decays within that time frame. To date these fossils, the nearby rock layers containing different radioactive isotopes with longer decay periods are used. When paleontologists discover bones in the ground, one of the first things they do is study the layers of volcanic rock, such as ash or lava, which locks in radioactive isotopes in crystal form. Lying above and below the fossils, these layers bookend the geologic period. The researchers collect samples of the volcanic rock layers in order to assign them dates. The samples of volcanic deposits are taken to a lab and crushed. The fragments are sorted…

Almost 7,000 languages are spoken around the world today, but some linguistic researchers believe that half of them will disappear this century. 6,909 languages are spoken worldwide. Most of the world's population speaks a small percentage of the languages in existence. The 83 most common languages are spoken by 80% of the world. The 3,500 least common languages are spoken by 0.2% of the world's population. 500 languages, mainly tribal tongues, are in immediate danger of dying out. About 20 languages currently are spoken by just one person. The Bo language died last year with the last remaining speaker, Boa Sr. [left]. 500,000 people use American Sign Language, one of the world's most popular gestural languages. Up to 528 classes of nouns, which describe nouns with physical characteristics such as…

Q Why doesn't hair grow uniformly on the body? A Ever wonder why your eyebrows don't grow as long as the hair on your head? In recent years, researchers have mapped a series of complex interactions between signaling molecules, hormones and follicles that affect how a human's five million hairs grow. But hair growth—particularly the mechanisms that drive the process—is still poorly understood. Signaling molecules program each hair follicle to either let a hair grow (anagen phase), stop its growth (catagen phase), or rest (telogen phase). The length of a hair depends on how long its anagen phase lasts, which can range from many years for a hair on your scalp to just a few months for eyebrow hairs. Female sex hormones, such as estrogen, prolong the duration of the…

Schools of female beluga sturgeon, their bodies swollen with eggs, swim up the Volga River from the Caspian Sea to seek out their spawning grounds. They lay their eggs on the pebbly river bottom before crowds of males arrive. The fertilized eggs later hatch into miniature sturgeon that may eventually make their way back to the Caspian Sea. Unfortunately, this pristine image no longer exists. Construction of the Volgograd dam on the river in 1955 blocked the fish from their spawning grounds. The sturgeon now found in the Volga originated in hatcheries and were dumped into the river in an effort to restore the population. It hasn't been enough. Between 1961 and 2002, the number of the fish entering the Volga—once the caviar industry's most productive river—fell by 89 percent.…

German-Austrian engineer Eugen Sanger proposes designs for a winged reusable spacecraft. NASA, the U.S. military and the aerospace company North American Aviation use Sanger's ideas to create the X-15, a winged craft that provides data about hypersonic flight in the upper boundaries of the atmosphere. Air Force and NASA engineers develop the X-24B [above], which tested the lifting-bodies concept, or wingless, unpowered reentry and landing. President Nixon formally proposes the development of a reusable space-transportation system. The first space-shuttle engine is tested at the National Space Technology Laboratories in Mississippi. Shuttle prototype Enterprise successfully completes a series of approach-and-landing tests. On April 12, the space shuttle Columbia is launched [below]. The orbital flight lasts two days. The Soviet Buran spaceplane [above] is successfully launched into orbit, but the program is…

Dating sediments by radioactive decay is a powerful analytical tool. But many factors can confuse dating, and special care must be taken to ensure an accurate age for a rock. Earth's crust is in constant motion because of geologic processes such as plate tectonics. Over time, the rocks in which a fossil is embedded may be moved, turned upside down, split up, or have different-aged rock intrude. Scientists map an area's entire geologic history. Aware that different types of rock have unique geometric and chemical signatures, researchers can determine how various formations originally fit together. Volcanic eruptions and other events may have reheated rocks so that some of their gaseous argon-40 isotopes have leaked out. That makes the measured ratio of the radioactive elements a poor indicator of the age…

1 Connect all the dots with each other, using a single, unbroken line consisting of vertical and horizontal stretches. The line cannot cross itself. Some of the squares contain a number, and this number tells you how many of the sides of that box are included in the line. 2 A kitchen floor has a very unusual shape. Which two of the tiles below can be combined to cover the entire floor, without overlaps or gaps? 3 Each of the colors of apples represents a weight: 2, 3, 4, 5 and 6. How many yellow apples must you put on the right side of the last scale for it to balance? Headbreakers 1. See diagram. 2. See diagram, A and E. 3. 4. Yellow apples weigh 5, green apples weigh…