7 April 2011:? After 3 ? years came in the background by the empty is the NASA spacecraft dawn on the threshold of a new world. It is deep in the asteroid belt, less than 4 months of huge asteroid Vesta.
"We are close in," says Marc Rayman, Dawn's chief engineer and mission Manager. "And I am more and more excited every day!"
Dawn will enter orbit around Vesta in July 2011, always the first space probe to a body in the asteroid belt orbiting. After a detailed study of the uncharted alien world for a year, is the probe pull a still impressive first. It will leave Vesta, fly to the planet Ceres dwarf, and give it orbit.
"This is unprecedented," says Rayman. "Any probe has ever circle the two objective body, much less worlds in the asteroid belt." "A few probes of this vast region of space have passed through, but no one could stop and to develop intimate portrait of the people."
A conventional Spacecraft Gets a boost from a big rocket then coasts to your destination. With enough fuel for which it would too heavy significant changes in the speed or direction on the way to start.
Dawn is far more fuel. Over 65 feet, collect the solar generators makes from the Sun to ionise atoms of Xenon gas. These ions are of a strong electric field produce a soft boost in the background from the back of the spaceship sold. This effect of Gossamer allows the frictionless weightless conditions of space to build strength, so that the spacecraft continuously receives speed.
"This probe reaches ultimately fantastic high speed in the consume very little Treibmittel--use only one kilogram of Xenon every four days, although its engines are almost constantly active."
With this system of dawn, rising was steadily to and to redesign its orbit around the Sun, slowly out to his goal, getting closer and closer and closer, as it comes to loops.
"The time, the spacecraft in the vicinity of Vesta is, its orbit much like asteroid,", says Rayman. "So can upon arrival, dawn in orbit glide gently as it has moved 3 ? years."*
A conventional spacecraft into orbit in a dramatic, moans nail biting instant. The mission team is riveted on the telemetry in the mission with their eyes, that the last important maneuver smoothly together.
"With Dawn, there is no one big manoeuvres, no fiery burn, no single critical moment." Dawn's entry in the orbit are not unlike which the probe is almost constantly, what it does when you read this article. In fact, when dawn slithers into orbit, I slept may. "Or if it's Friday night I will dance, or if it is Saturday may I out the images of dragonflies."
But you can bet that he will be in mission control when the images come in start.
"It is incredibly exciting to watch dawn at the Vesta close." Witnesses we will grow the unattractive spot in the first remote images in a world of full size as we closer and closer, loop ends only 110 km above the surface. This is closer than the ISS to Earth is! "We are right there, and if there is no high trees we are safe."
After exploring Vesta for a year, Dawn takes farewell by the Rocky world as gently as it came, climbing along a spiral, gradually getting further and further away, the loop always longer and longer, up to the asteroid gravity gently free of the probe. Dawn will orbit the Sun again for on its own, as it is now. It will be completed about two-thirds of a round, before arriving at Ceres.
There it is again in an orbit around a new world, led by ion engines as quiet as space itself move carefully.
"Even if we imagine a sound, the slightest whisper that softest sighs would it." "Or it says for us the secret make an Interplanetary Spaceship to travel and discover the remote, alien world, the dreams carry those thus on Earth who can know the Cosmos long."
Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA
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