Agriculture
Springing forward
Middle school science adventures
Got Milk? How?
Amphibians
Newts
Frogs and Toads
Salamanders and Newts
Animals
Cannibal Crickets
G-Tunes with a Message
Saving Africa's Wild Dogs
Behavior
The Other Side of the Zoo Fence
Lightening Your Mood
GSAT Mathematics Quiz, Teaching Math, teaching anxiety
Birds
Kingfishers
Mockingbirds
Robins
Chemistry and Materials
Lighting goes digital
Cooking Up Superhard Diamonds
Sweeeet! The Skinny on Sugar Substitutes
Computers
Lighting goes digital
Middle school science adventures
New eyes to scan the skies
Dinosaurs and Fossils
A Really Big (but Extinct) Rodent
Some Dinos Dined on Grass
Middle school science adventures
E Learning Jamaica
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Results of GSAT are in schools this week
Earth
A Grim Future for Some Killer Whales
Earth from the inside out
Meteorites may have sparked life on Earth
Environment
Plant Gas
Alien Invasions
Forests as a Tsunami Shield
Finding the Past
A Volcano's Deadly Ash
A Big Discovery about Little People
Ancient Cave Behavior
Fish
Cleaning Up Fish Farms
Basking Sharks
Skates
Food and Nutrition
Food for Life
Packing Fat
Building a Food Pyramid
GSAT English Rules
Who vs. Whom
Adjectives and Adverbs
Subject and Verb Agreement
GSAT Exam Preparation Jamaica
Tarrant High overcoming the odds
Scotiabank Jamaica Foundation Grade Six Achievement Test (GSAT) Scholarships
Ministry of Education Announces 82 GSAT Scholarships for 2010
GSAT Exams Jamaica Scholarships
GSAT Practice Papers | GSAT Mathematics | Maths
Access denied - Disabled boy aces GSAT
GSAT Exam Preparation
GSAT Mathematics
GSAT Practice Papers | GSAT Mathematics | Maths
Deep-space dancers
Setting a Prime Number Record
Human Body
Hear, Hear
Disease Detectives
Sun Screen
Invertebrates
Earthworms
Corals
Shrimps
Mammals
Asian Elephants
Blue Whales
Weasels and Kin
Parents
Expert report highlights the importance to parents of reading to children!
Children and Media
Choosing a Preschool: What to Consider
Physics
The Pressure of Scuba Diving
Echoes of a Stretched Egg
Project Music
Plants
Sweet, Sticky Science
Underwater Jungles
Fastest Plant on Earth
Reptiles
Crocodilians
Geckos
Crocodiles
Space and Astronomy
Phantom Energy and the Big Rip
Galaxies Divide Sharply Along Color Lines
Unveiling Titan
Technology and Engineering
Reach for the Sky
A Clean Getaway
Drawing Energy out of Wastewater
The Parts of Speech
What is a Preposition?
Pronouns
What is a Verb?
Transportation
Reach for the Sky
Robots on the Road, Again
Ready, unplug, drive
Weather
Watering the Air
Arctic Melt
Either Martians or Mars has gas
Add your Article

Gravity Tractor as Asteroid Mover

Movie producers love the idea, partly because it's so scary and partly because it could actually happen. The setup is this: An asteroid is screaming toward Earth. A collision is inevitable. When the rocky object hits the planet, lots of people will die. In the movies, a daring hero comes up with a crazy plan to destroy or divert the asteroid and save the day. In real life, scientists have come up with more reasonable plans that might actually work if this rare situation ever comes up. One solution, say two NASA scientists and astronauts, is a 20-ton spacecraft called a gravitational tractor. First, the tractor would zoom up to the threatening asteroid and stop a short distance away. It would hover there, firing its thrusters just enough to overcome the force of gravity between the spacecraft and the asteroid. The tractor could then use its own gravity to tug the asteroid off course. It would take about a year for the spacecraft to drag a medium-sized asteroid that measures 200 meters (660 feet) across and weighs 60 million tons away from Earth's path. An asteroid this large could cause major damage to our planet. Some asteroids are even larger than this, and it would require bigger tractors to pull them enough to remove the threat. The tricky part is that the spacecraft would have to arrive at the Earth-bound asteroid about 20 years before the asteroid was due to hit Earth. It would take a much smaller nudge then to move the asteroid out of the way than it would take if the asteroid were closer to its impact time. Still, the tractor idea is better than many previously proposed strategies for asteroid avoidance. Blowing up asteroids, for example, wouldn't work because the rocky bodies are too full of air holes to burst apart. Nor is it reasonable to have a spacecraft attach itself to an asteroid and use its engines to steer the object away. That's because asteroids spin. Unless the craft stopped the asteroid from spinning, each thrust would push the asteroid in a different direction. A gravitational tractor could get around these problems. Don't spend too much time worrying about asteroids falling on your house, however. The chances of a collision occurring in your lifetime are very slim. If it does happen, though, scientists will do everything they can to keep you from getting hurt. Sounds pretty heroic to me!E. Sohn

Gravity Tractor as Asteroid Mover
Gravity Tractor as Asteroid Mover








Designed and Powered by HBJamaica.com™