Agriculture
Springing forward
Earth-Friendly Fabrics
Growing Healthier Tomato Plants
Amphibians
Newts
Salamanders
Bullfrogs
Animals
A Fallout Feast for Crabs
Helping the Cause of Macaws
The History of Meow
Behavior
Baby Number Whizzes
The chemistry of sleeplessness
Pollution at the ends of the Earth
Birds
Cranes
Waterfowl
Emus
Chemistry and Materials
The Buzz about Caffeine
Supersonic Splash
Atom Hauler
Computers
A Light Delay
Galaxies far, far, far away
Play for Science
Dinosaurs and Fossils
Hunting by Sucking, Long Ago
A Living Fossil
South America's sticky tar pits
E Learning Jamaica
Results of GSAT are in schools this week
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Earth
Watering the Air
Ice Age Melting and Rising Seas
Giving Sharks Safe Homes
Environment
Fishing for Fun Takes Toll
A Stormy History
A 'Book' on Every Living Thing
Finding the Past
Preserving Ancient Warrior Paint
Decoding a Beverage Jar
Fakes in the museum
Fish
Whale Sharks
Saltwater Fish
Mako Sharks
Food and Nutrition
Strong Bones for Life
The Essence of Celery
A Pepper Part that Burns Fat
GSAT English Rules
Problems with Prepositions
Whoever vs. Whomever
Order of Adjectives
GSAT Exam Preparation Jamaica
Preparing for the GSAT Exam
2014 GSAT Results for Jamaican Kids
10 Common Mistakes When Preparing for the GSAT Math Test
GSAT Exams Jamaica Scholarships
42,000 students will sit for the GSAT Exam in two weeks
GSAT Practice Papers | GSAT Mathematics | Maths
Access denied - Disabled boy aces GSAT
GSAT Mathematics
Play for Science
Math Naturals
Math is a real brain bender
Human Body
A Sour Taste in Your Mouth
What the appendix is good for
Tapeworms and Drug Delivery
Invertebrates
Crabs
Nautiluses
Sea Urchin
Mammals
Walrus
Glider
Golden Retrievers
Parents
Expert report highlights the importance to parents of reading to children!
What Not to Say to Emerging Readers
Raise a Lifelong Reader by Reading Aloud
Physics
Electric Backpack
Powering Ball Lightning
Speedy stars
Plants
Farms sprout in cities
The algae invasion
Making the most of a meal
Reptiles
Tortoises
Geckos
Lizards
Space and Astronomy
A Whole Lot of Nothing
A Dead Star's Dusty Ring
An Icy Blob of Fluff
Technology and Engineering
Sugar Power for Cell Phones
A Micro-Dose of Your Own Medicine
Spinach Power for Solar Cells
The Parts of Speech
What is a Noun
What is a Preposition?
Countable and Uncountable Nouns
Transportation
Flying the Hyper Skies
Ready, unplug, drive
Where rivers run uphill
Weather
Polar Ice Feels the Heat
Either Martians or Mars has gas
Arctic Melt
Add your Article

Riding Sunlight

Hundreds of years ago, sailing ships carried explorers across the ocean from Europe to America and beyond. A future generation of explorers might set sail, too—not across water, but across outer space. Later this year, researchers plan to test a solar sail spacecraft that uses sunlight instead of wind to move. In theory, spacecraft pushed by light could cruise at high speeds without using any fuel. Fast and practical travel to other planets and even stars might then become possible. The first solar sail flight could be monumental, says Louis Friedman. It could have the same sort of impact as the pioneering airplane flight made by the Wright brothers in 1903. Before the Wright brothers and other inventors showed the way, the idea of humans in flight seemed ridiculous to many people. A hundred years later, passenger jets and private planes crisscross the sky all day long. Now, it's the idea that sunlight can propel spacecraft that many people find hard to believe. Friedman and others are trying to turn this crazy idea into reality. The biggest challenge is figuring out how to do what you know should be possible, Friedman says. The forces are there. It's a matter of harnessing them. Friedman heads the Cosmos 1 solar sail project. He's also executive director of The Planetary Society in Pasadena, Calif. "The Wright brothers flew for 12 seconds," Friedman says. "They went nowhere, but they were successful. If we can fly for just 2 days, it'll be a success." Solar pressure Sailing in space is similar to sailing on water, with two major differences. There's no water in space. And there's no wind. This may sound confusing because there is something called a solar wind. Unlike the breezes we're used to on Earth, however, the solar wind is a stream of particles spit out by the sun. Magnetic fields help protect our planet from these particles. Solar sailing has nothing to do with the solar wind. Instead, solar sails catch rays of light. It may be hard to imagine, but sunlight itself can make objects move. Light is a form of energy, and it exerts pressure. We don't feel the pressure of sunlight on Earth because other forces that act on us are much stronger. Outer space, however, is practically empty. Nothing gets in the way of the force exerted by light. Understanding how solar sails work also hinges on a law of physics discovered by Isaac Newton in the 1600s. His third law of motion states that for every action, there's an equal and opposite reaction. For example, when you let air out of a balloon, the air shoots out in one direction and the balloon zips off in the opposite direction. On a skateboard, pushing your foot back makes the board go forward. Solar sails have mirror-like blades that reflect sunlight. When light gets reflected back in one direction, the sail moves in the opposite direction. Light travel Light exerts only a tiny amount of force. So, to get a real push, a solar sail must be as large and lightweight as possible. The solar sail developed by Friedman's team is made of a very light, shiny plastic. It has eight blades, arranged in a circle. Each blade is 15 meters (50 feet) long and even thinner than an ordinary garbage bag. At first, a solar sail might travel at no more than a few millimeters a second—slower than a snail. With nothing in space to slow it down, though, the sail could, in theory, reach speeds as high as 100,000 miles per hour, Friedman says. That would be fast enough to get to other planets in just a few years. Changing the angle of its sails would allow the spacecraft to change direction. It's like using a rudder to control a boat's direction. Launch date Friedman's team plans to launch its solar sail spacecraft, Cosmos 1, in March. This will be the first attempt to get light pressure to propel a vehicle in outer space. People are skeptical. "Even I'm not sure the first attempt will succeed," Friedman says. "But I don't think anyone thinks the theory is wrong." Friedman imagines a day in the distant future when solar sails would crowd space in the same way that airplanes crowd the sky on Earth today. For now, he and his team would be happy to take even a small step toward an entirely new category of space exploration. "We know with other inventions that people try, fail, try again, and then succeed," Friedman says. The dramatic flight of Cosmos 1 is coming up. It may turn out to be the start of a great adventure.

Riding Sunlight
Riding Sunlight








Designed and Powered by HBJamaica.com™