Happy Anniversary, Neptune!

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Happy Anniversary, Neptune!

Post by neufer » Mon Jul 11, 2011 7:46 pm

http://www.universetoday.com/87392/happy-anniversary-neptune/#more-87392 wrote:
Happy Anniversary, Neptune!
by Tammy Plotner on July 11, 2011

<<Today, July 11, 2011 marks the first full orbit of the planet Neptune since its discovery on the night of September 23-24, 1846. But there’s a lot more to learn about this anniversary than just the date. Step inside and let’s find out…

Pinpointing Neptune is a wonderful story. For many years we’ve been taught that the discovery of Neptune was done by mathematical calculations. This came about in 1821 when Alexis Bouvard was publishing his findings for Uranus and noticed a gravitational perturbation. This led him to hypothesize an unknown body was crossing the path. Enter miscommunications, politics and astronomer John Adams…

“It is more likely that Adams realised that his proposed orbits were moving ever closer to a “forbidden” zone of resonance.” says Brian Sheen of Roseland Observatory. “Uranus orbits in 84 years, Neptune in 165, nearly a 2:1 resonance, this brings about much greater perturbations than were being measured. In fact the mid 19th century is a quiet period and much bigger swings are evident now.”

In 1843 John Couch Adams used the data Bouvard proposed to begin working on a proposed orbit, but it would be several years later before Urbain Le Verrier verified its existence through physical observation – at the same time as Johann Gottfried Galle. Says Sheen; “It is often said that Adams never published his results. In fact a published paper was printed by November 1846 and appeared in the 1851 Nautical Almanack published in 1847.”

Unknown to both at the time – and in a great twist of irony – Galileo had actually observed Neptune on December 28, 1612, and again on January 27, 1613, but didn’t realize it was a planet. Small wonder he thought it was a fixed star, because as luck would have it, Neptune turned retrograde at the same time as his first observation! But Galileo was a great observer and made drawings of his find. Given all that we know today, it’s pretty astonishing his limited equipment was able to perceive the blue planet, let alone realize its minor movement against the ecliptic meant something. After all, the very concept of the ecliptic plane was new!

“It has been known for several decades that this unknown star was actually the planet Neptune,” says University of Melbourne physicist, David Jamieson. “Computer simulations show the precision of his observations revealing that Neptune would have looked just like a faint star almost exactly where Galileo observed it.” But we digress…Today, July 11 would be the anniversary of Neptune’s first full barycentric orbit – a celebration that has taken us 164.79 years of waiting to celebrate. Tomorrow, July 12 is the anniversary of Neptune’s heliocentric completion. However, don’t expect Neptune to be in the exact same position as it was on either date. While over 150 years is but a wink in the cosmic eye, it is certainly more than enough time for our solar system to have shifted That having been over simply said, what will happen at 21:48 and 24.6 seconds UT on July 11 is that Neptune will return to its exact longitudinal position in respect to the invariable plane. Is it close to its discovery point? Well, in a sense, yes. It will be within 1.5 arc seconds of its 1846 location relative to the barycentre. In visual terms, that’s just a whisker.

As you can see, it’s going to be quite late at night before Neptune has well cleared the horizon – but what an opportunity! Because of its small size, I recommend using a telescope for stability and printing a map from a planetarium program for more detailed star fields. You can expect to see a slightly blue colored disk that averages about magnitude 8 (well within reach of smaller scopes). If you have never seen Neptune before, compare it in your mind’s eye to one of Jupiter’s moons and you’ll be able to pick it out of starry background much easier.

Good luck, clear skies and happy anniversary Neptune! Many thanks to Brian Sheen of Roseland Observatory!>>
http://astrobob.areavoices.com/?blog=78068 wrote: Hot on the trail of the asteroid Vesta
Posted on July 1, 2011 by astrobob Wow, Vesta is finally coming into focus!

While I love watching Vesta come ever hither through Dawn’s eyes, you can also see it live in the flesh in the early morning sky. All you need is a pair of binoculars and a good map. You’re on your own with the binoculars, but I’m happy to share a map for how to find the asteroid.

Vesta is currently magnitude 6.3 – near the naked eye limit for sky watchers who have access to a dark location – and located in the eastern half of Capricornus the Sea Goat, a constellation that looks like a saggy triangle. While Capricornus is not a particularly bright grouping, you can locate it easily enough by using the Summer Triangle. Shoot a line from Altair at the bottom of the Summer Triangle to the pair of stars Alpha and Beta Capricorni. A little more than one outstretched 'fist' to their left, you'll see the pair of Delta and Gamma. Once there, use the detailed map created with Stellarium.

Now for the hard part. Vesta doesn’t get high enough to see with ease until around 1 a.m. local time in early July. Viewing circumstances improve with time. By mid-month, you can catch it around midnight, and in early August, when Vesta is brightest and closest, it’ll be up at the end of the 10 o’clock news.

Through binoculars Vesta looks exactly like a ‘star’ that slowly creeps to the southwest night by night through the stars of the Sea Goat. Its appearance through a telescope is identical. That’s why these small bodies were named ‘asteroids’, from the Greek for ‘star-like’.

In early August, it will have brightened to magnitude 5.7 and be fairly easy to see from a dark sky if you know exactly where to look. It’s always fun to connect to a big time space mission like Dawn by experiencing it with your own eyes.>>
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Re: Happy Anniversary, Neptune!

Post by Ann » Mon Jul 11, 2011 8:48 pm

Happy anniversary indeed, blue, blue planet Neptune! :D
(And not only are you a beauty, but I think it's kind of cool that astronomers found you because they detected the invisible gravitational influence of you on planet Uranus, so they figured out where they should search for you...)

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Re: Happy Anniversary, Neptune!

Post by BMAONE23 » Mon Jul 11, 2011 9:16 pm

Today is also the Anniversary (Birthday) of the 7-ELEVEN chain of convenience stores get a free slurpee today

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Re: Happy Anniversary, Neptune!

Post by neufer » Tue Jul 12, 2011 1:08 am

BMAONE23 wrote:
Today is also the Anniversary (Birthday) of the 7-ELEVEN chain of convenience stores
get a free slurpee today
http://en.wikipedia.org/wiki/Kwik-E-Mart wrote:
Image
<<The Kwik-E-Mart is a convenience store that sells the usual fare at extraordinarily high prices, including the always popular Squishee.
Squishee is a frozen slushie is an apparent reference to 7-Eleven's Slurpee. Squishees are reputed for being dangerous to health — Squishee flavorings have, if ingested in sufficient quantities, hallucinatory properties. Squishees allegedly contain no natural ingredients (not even pure water), create dangerous cases of brain freeze, and are even described as "a thick, gloopy, tooth-rotting mixture of crushed ice and syrup". Flavors include: blue, red, lime green, Chutney, Wheatgrass, Champagne, cherry, and the Twenty-One Syrup Salute.

The Kwik-E-Mart chain was started somewhere in the Himalaya, where the world's first convenience store still stands on a mountain peak. Visiting pilgrims are allowed to ask three questions of the resident all-knowing guru. In July 2007, eleven 7-Eleven locations in the United States and one in Canada were transformed into Kwik-E-Marts as part of a special promotion for The Simpsons Movie. For a limited time, 7-Elevens across North America also sold various Simpsons products, such as "Squishees", "Buzz Cola" and "Krusty-Os cereal". Also in 2007, gift shops modeled after the "Kwik-E-Marts" were opened in Universal Studios Florida and Universal Studios Hollywood, where they are a companion to "The Simpsons Ride".

Springfield's Kwik-E-Mart is owned and operated by an Indian American named Apu Nahasapeemapetilon, who mans the store with his brother Sanjay. Apu is an extremely devoted convenience store clerk/owner, rarely closing his store and occasionally working 96 hour shifts. He quite often ignores his wife Manjula and their eight children (Anoop, Uma, Nabendu, Poonam, Priya, Sandeep, Sashi, and Gheet) so that he can be at the store as much as possible and is usually very hesitant to leave his brother in charge. Apu is quite proud of his work, and proudly gouges customers and sells tainted merchandise, such as rotten meat or expired milk. Springfield's Kwik-E-Mart is quite often the target of robbers, leading to Apu having been shot on several occasions. The Kwik-E-Mart does not accept checks from Chief Wiggum, Reverend Lovejoy and Homer Simpson. Apu is a naturalised U.S. citizen and holds a Ph.D. degree in computer science. He graduated first in his class of seven million at 'Caltech' — Calcutta Technical Institute — going on to earn his doctorate at the Springfield Heights Institute of Technology. Apu began working at the Kwik-E-Mart during his college years to pay off his student loan, but stayed afterward as he had come to enjoy his job and the friends he had made. He remained an illegal immigrant until Mayor Quimby proposed a municipal law to expel all undocumented aliens. Apu responded by purchasing a forged birth certificate from the Springfield Mafia that listed his parents as U.S. citizens Herb and Judy Nahasapeemapetilon, but when he realized he was forsaking his origins, he abandoned this plan and instead successfully managed to pass his citizenship test with help from Lisa and Homer Simpson. Thus, he refers to himself as a "semi-legal immigrant".>>
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Neptune compleats One Orbit

Post by orin stepanek » Tue Jul 12, 2011 8:51 pm

http://hubblesite.org/newscenter/archiv ... s/2011/19/

Today, Neptune has arrived at the same location in space where it was discovered nearly 165 years ago. To commemorate the event, NASA's Hubble Space Telescope has taken these "anniversary pictures" of the blue-green giant planet.
Last edited by orin stepanek on Tue Jul 12, 2011 9:44 pm, edited 1 time in total.
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Re: Neptund compleats One Orbit

Post by neufer » Tue Jul 12, 2011 9:08 pm

Art Neuendorffer

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Re: Neptund compleats One Orbit

Post by Ann » Tue Jul 12, 2011 9:27 pm

I wouldn't call Neptune blue-green.

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Re: Neptund compleats One Orbit

Post by orin stepanek » Tue Jul 12, 2011 9:43 pm

Ya beat me to it Art! Moderators are going to have to merge the Threads! :shock: :wink:
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Re: Neptund compleats One Orbit

Post by neufer » Tue Jul 12, 2011 10:00 pm

Ann wrote:
I wouldn't call Neptune blue-green.
What about Neptund :?:
http://en.wikipedia.org/wiki/Green wrote: <<Many Asian languages have no word distinguishing blue from green, although recently published dictionaries do make the distinction. In Japanese, despite the existence of a word in the modern language meaning "green", the color is sometimes described as blue, as in blue traffic light and blue leaves, reflecting the absence of a word meaning "green" in old Japanese. The Thai word เขียว besides meaning "green" also means "rank" and "smelly" and holds other unpleasant associations.

Culturally, green has broad and sometimes contradictory meanings. In some cultures, green symbolizes hope and growth, while in others, it is associated with death, sickness, envy, or the devil. The most common associations, however, are found in its ties to nature. For example, Islam venerates the color, as it expects paradise to be full of lush greenery. Green is also associated with regeneration, fertility and rebirth for its connections to nature. Recent political groups have taken on the color as symbol of environmental protection and social justice, and consider themselves part of the Green movement, some naming themselves Green parties. This has led to similar campaigns in advertising, as companies have sold green, or environmentally friendly, products.>>
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Re: Neptund compleats One Orbit

Post by orin stepanek » Tue Jul 12, 2011 11:45 pm

neufer wrote: What about Neptund :?:
Spelling hiccup! :oops:
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Re: Neptune compleats One Orbit

Post by Beyond » Wed Jul 13, 2011 4:44 am

Green-green is green they say, on the far side of the hill...
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Re: Neptune compleats One Orbit

Post by Ann » Wed Jul 13, 2011 6:59 am

Look at that beautiful landscape! The grass and the tree are so green-green, and the sky and water are so blue-green!
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Re: Happy Anniversary, Neptune!

Post by neufer » Thu Jul 14, 2011 5:09 pm

http://dawn.jpl.nasa.gov/multimedia/dawn_vesta_image_070911.asp wrote: July 14, 2011 - PASADENA, Calif. -- NASA's Dawn spacecraft obtained this image with its framing camera on July 9, 2011. It was taken from a distance of about 26,000 miles (41,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 2.4 miles (3.8 kilometers).
http://en.wikipedia.org/wiki/Wrinkle_%28skin%29 wrote: <<The wrinkles that occur in skin after prolonged exposure to water are sometimes referred to as pruney fingers or water aging. This is a temporary skin condition where the skin on the palms of the hand or feet becomes wrinkly. The increased surface area of the affected area may provide better traction in water.

In recent past the common explanation was based on water absorption in the keratin-laden epithelial skin when immersed in water, causing the skin to expand and resulting in a larger surface area, forcing it to wrinkle. Usually the tips of the fingers and toes are the first to wrinkle because of a thicker layer of keratin and an absence of hairs which secrete the protective oil called sebum.

In 1935 however, Lewis and Pickering were studying patients with palsy of a large nerve in the arm (the median nerve) when they discovered that skin wrinkling did not occur in the areas of the patients' skin normally innervated by the damaged nerve. This suggested that the nervous system plays an essential role in wrinkling, so the phenomenon could not be entirely explained simply by water absorption. Recent research shows that wrinkling is related to vasoconstriction. Water probably initiates the wrinkling process by altering the balance of electrolytes in the skin as it diffuses into the hands and soles via their many sweat ducts. This could alter the stability of the membranes of the many neurons that synapse on the many blood vessels underneath skin, causing them to fire more rapidly. Increased neuronal firing causes blood vessels to constrict, decreasing the amount of fluid underneath the skin. This decrease in fluid would cause a decrease in tension, causing the skin to become wrinkly.

This insight resulted in bedside tests for nerve damage and vasoconstriction. Wrinkling is often scored with immersion of the hands for 30 minutes in water or EMLA cream with measurements steps of 5 minutes, and counting the number of visible wrinkles in time. Not all healthy persons have finger wrinkling after immersion, so it would be safe to say that sympathetic function is preserved if finger wrinkling after immersion in water is observed, but if the fingers emerge smooth it cannot be assumed that there is a lesion to the autonomic supply or to the peripheral nerves of the hand.>>
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Re: Neptune compleats One Orbit

Post by Beyond » Thu Jul 14, 2011 7:05 pm

Ann wrote:Look at that beautiful landscape! The grass and the tree are so green-green, and the sky and water are so blue-green!
Ann
Yes, because we are seeing the color that is not absorbed and that is being reflected back at us. I wonder what they would really look like if the green stuff absorbed the green wavelenghts and the sky absorbed the blue wavelenghts. We might just go YUCK :!:
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Re: Happy Anniversary, Neptune!

Post by BMAONE23 » Thu Jul 14, 2011 7:32 pm

neufer wrote:
http://dawn.jpl.nasa.gov/multimedia/dawn_vesta_image_070911.asp wrote: July 14, 2011 - PASADENA, Calif. -- NASA's Dawn spacecraft obtained this image with its framing camera on July 9, 2011. It was taken from a distance of about 26,000 miles (41,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 2.4 miles (3.8 kilometers).
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Re: Neptune compleats One Orbit

Post by rstevenson » Thu Jul 14, 2011 11:31 pm

Beyond wrote: I wonder what they would really look like if the green stuff absorbed the green wavelenghts and the sky absorbed the blue wavelenghts. We might just go YUCK :!:
Roughly...
2585946-dutch-landscape-in-spring.jpg
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Re: Neptune compleats One Orbit

Post by owlice » Fri Jul 15, 2011 12:12 am

That has a beauty all its own; thanks, Rob!
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Re: Neptune compleats One Orbit

Post by Beyond » Fri Jul 15, 2011 12:57 am

rstevenson wrote:
Beyond wrote: I wonder what they would really look like if the green stuff absorbed the green wavelenghts and the sky absorbed the blue wavelenghts. We might just go YUCK :!:
Roughly...
2585946-dutch-landscape-in-spring.jpg
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SAY....that's alright! Now....how good would the mosquitos show up :?: :?:
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Re: Neptune completes One Orbit

Post by bystander » Fri Jul 15, 2011 5:02 am

Neptune Completes Its First Circuit Around The Sun Since Its Discovery
The Hubble Heritage Project | 2011 July 12

On July 12, 2011 Neptune has arrived at the same location in space where it was discovered nearly 165 years ago. To commemorate the event, NASA's Hubble Space Telescope has taken these "anniversary pictures" of the blue-green giant planet.

Neptune is the most distant major planet in our solar system. German astronomer Johann Galle discovered the planet on September 23, 1846. At the time, the discovery doubled the size of the known solar system. The planet is 2.8 billion miles (4.5 billion kilometers) from the Sun, 30 times farther than Earth. Under the Sun's weak pull at that distance, Neptune plods along in its huge orbit, slowly completing one revolution approximately every 165 years.

These four Hubble images of Neptune were taken with the Wide Field Camera 3 on June 25-26, during the planet's 16-hour rotation. The snapshots were taken at roughly four-hour intervals, offering a full view of the planet. The images reveal high-altitude clouds in the northern and southern hemispheres. The clouds are composed of methane ice crystals.

The giant planet experiences seasons just as Earth does, because it is tilted 29 degrees, similar to Earth's 23-degree-tilt. Instead of lasting a few months, each of Neptune's seasons continues for about 40 years.

The snapshots show that Neptune has more clouds than a few years ago, when most of the clouds were in the southern hemisphere. These Hubble views reveal that the cloud activity is shifting to the northern hemisphere. It is early summer in the southern hemisphere and winter in the northern hemisphere.

In the Hubble images, absorption of red light by methane in Neptune's atmosphere gives the planet its distinctive aqua color. The clouds are tinted pink because they are reflecting near-infrared light.

A faint, dark band near the bottom of the southern hemisphere is probably caused by a decrease in the hazes in the atmosphere that scatter blue light. The band was imaged by NASA's Voyager 2 spacecraft in 1989, and may be tied to circumpolar circulation created by high-velocity winds in that region.

The temperature difference between Neptune's strong internal heat source and its frigid cloud tops, about minus 260 degrees Fahrenheit, might trigger instabilities in the atmosphere that drive large-scale weather changes.

Neptune has an intriguing history. It was Uranus that led astronomers to Neptune. Uranus, the seventh planet from the Sun, is Neptune's inner neighbor. British astronomer Sir William Herschel and his sister Caroline found Uranus in 1781, 55 years before Neptune was spotted. Shortly after the discovery, Herschel noticed that the orbit of Uranus did not match the predictions of Newton's theory of gravity. Studying Uranus in 1821, French astronomer Alexis Bouvard speculated that another planet was tugging on the giant planet, altering its motion.

Twenty years later, Urbain Le Verrier of France and John Couch Adams of England, who were mathematicians and astronomers, independently predicted the location of the mystery planet by measuring how the gravity of a hypothetical unseen object could affect Uranus's path. Le Verrier sent a note describing his predicted location of the new planet to the German astronomer Johann Gottfried Galle at the Berlin Observatory. Over the course of two nights in 1846, Galle found and identified Neptune as a planet, less than a degree from Le Verrier's predicted position. The discovery was hailed as a major success for Newton's theory of gravity and the understanding of the universe.

Galle was not the first to see Neptune. In December 1612, while observing Jupiter and its moons with his handmade telescope, astronomer Galileo Galilei recorded Neptune in his notebook, but as a star. More than a month later, in January 1613, he noted that the "star" appeared to have moved relative to other stars. But Galileo never identified Neptune as a planet, and apparently did not follow up those observations, so he failed to be credited with the discovery.

Neptune is not visible to the naked eye, but may be seen in binoculars or a small telescope. It can be found in the constellation Aquarius, close to the boundary with Capricorn.

Neptune-mass planets orbiting other stars may be common in our Milky Way galaxy. NASA's Kepler mission, launched in 2009 to hunt for Earth-size planets, is finding increasingly smaller extrasolar planets, including many the size of Neptune.

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
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Re: Happy Anniversary, Neptune!

Post by neufer » Sat Jul 16, 2011 4:24 pm

http://www.washingtonpost.com/national/ ... story.html

Destination asteroid: NASA probe arrives at ancient ‘mini moon’
By Brian Vastag, Published: July 15

<<After spiraling outward from Earth for four years, NASA’s Dawn probe is set to slide into orbit around the potato-shaped asteroid Vesta early Saturday for a year-long look at an ancient “mini moon.” Three hundred fifty miles wide and heavily cratered, Vesta formed some 4.5 billion years ago, when the sun was still young. By probing its secrets, scientists hope to catch a glimpse of how the planets, including Earth, formed out of a swirling disk of gas and dust. “We are exploring backward in time as far as we can,” said lead mission investigator Christopher Russell of the University of California at Los Angeles. “There’s going to be a whole bunch of surprises.”

Unlike most smaller asteroids — thought to be nearly uniform lumps of rock — Vesta is a “mini moon,” Russell said, made up of three layers: an iron core, a rocky mantle and an upper crust. Early in Vesta’s existence, Russell said, lava welled up from its interior and cooled to form a crust of volcanic rock. “Vesta is unique among the large asteroids,” said Richard Binzel, professor of planetary sciences at the Massachusetts Institute of Technology. “It’s the only one covered with a volcanic surface.”

Despite observations from the Hubble Space Telescope, many mysteries of Vesta’s origin and composition remain, including why the asteroid’s surface is so dark. [ :?: One of the many mysteries of Vesta is why the asteroid’s surface is so 'bright' (albedo ~ 0.423) It is the next asteroid destination, Ceres, that has the dark surface (albedo ~ 0.090).- A.C.N.]

Its solar wings spread wide, Dawn should begin orbiting Vesta around 1 a.m. Saturday. Vesta’s slight gravity — just 2 percent that of Earth’s — will gently capture the probe, which is closing in on the asteroid at just 100 miles per hour. “We’ve had a smooth flight,” Russell said of the $466 million mission that launched a year behind schedule.

For the next year, Dawn will slowly spiral toward Vesta’s surface, coming within 120 miles. As cameras snap photos, other instruments will probe the asteroid’s makeup. There may be hills, mountains and even extinct volcanoes on Vesta’s surface, Russell said. In 1997, images from the Hubble Space Telescope revealed an eight-mile-deep crater on Vesta’s southern hemisphere. The collision that carved the crater sent a huge plume of rock and dust hurtling through the solar system. Some of that material landed on Earth as meteorites, Russell said.

In fact, scientists estimate that some 20 percent of all meteorites came from Vesta, which was discovered by a German astronomer in 1806. The second-most-massive asteroid in the solar system, Vesta circles the sun in the asteroid belt between Mars and Jupiter. Had Jupiter’s massive gravity not interfered, the millions of space rocks in the asteroid belt might have coalesced into another planet, scientists say.

Unlike rocket-powered craft sent to Mars, Jupiter and other planets, Dawn is driven by a weak-but-steady ion engine. Powered by solar panels, Dawn’s engines zap a gas, xenon, with an electrical charge. As the charged gas shoots out a nozzle, it imparts a gentle push — equivalent to the weight of a sheet of paper sitting on your hand, said Mark Rayman, chief engineer for Dawn at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

But what Dawn lacks in power, it makes up in stamina. Its engines have been thrusting for some 1,000 days, steadily adding speed. Sipping just milligrams of xenon a day, the super-efficient engines leave Dawn with enough fuel to push itself toward a second asteroid. If all goes well, next summer the 65-foot-wide craft will depart Vesta and head toward the largest asteroid in the solar system, Ceres, with arrival scheduled for 2015. Ceres intrigues scientists because it apparently holds a huge reservoir of water, Russell said. If successful, Dawn’s double-destination mission will mark the first time a spacecraft has orbited two bodies in the solar system.>>
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