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Astronomy - Planets , Stars & Heavenly Bodies

The Rover

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'massive' does not refer to size B)

Here's a snippet from further down in the article:

"The stellar orbits in the galactic centre show that the central mass concentration of four million solar masses must be a black hole, beyond any reasonable doubt."

Is that Chuck at your door? :D

Edited by Patrycja
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Interesting article.

Earth's Artificial Ring: Project West FordWritten by Anthony Kendall on May 2nd, 2006 at 9:39 am From DamnInteresting.comwestford_overview.jpgAt the height of the Cold War in the late 1950s, all international communications were either sent through undersea cables or bounced off of the natural ionosphere. The United States military was concerned that the Soviets (or other "Hostile Actors") might cut those cables, forcing the unpredictable ionosphere to be the only means of communication with overseas forces. The Space Age had just begun, and the communications satellites we rely on today existed only in the sketches of futurists.

Nevertheless, the US Military looked to space to help solve their communications weakness. Their solution was to create an artificial ionosphere. In May 1963, the US Air Force launched 480 million tiny copper needles that briefly created a ring encircling the entire globe. They called it Project West Ford. The engineers behind the project hoped that it would serve as a prototype for two more permanent rings that would forever guarantee their ability to communicate across the globe.

The project itself was a virtually unqualified success. Though the first launch ended in failure, the second launch went without a hitch on May 10th, 1963. Inside the West Ford spacecraft, the needles were packed densely together in blocks made of a napthalene gel that would rapidly evaporate in space. This entire package of needles weighed only 20 kg. After being released, the hundreds of millions of copper needles gradually spread throughout their entire orbit over a period of two months. The final donut-shaped cloud was 15 km wide and 30 km thick and encircled the globe at an altitude of 3700 km.

westford_dipoles.jpgCopper Dipoles from Project West FordThe West Ford copper needles were each 1.8 cm long and 0.0018 cm in diameter and weighed only 40 micrograms. They were designed to be exactly half of the wavelength of 8000 MHz microwaves. This length would create strong reflections when the microwaves struck the copper needles, in effect making them tiny dipole anttennae each repeating in all directions the exact same signal they received.

The first attempt at remote communications using the West Ford belt was made on May 14th, 4 days after the launch. At this point, the dipoles had not completely spread out to fill their entire orbit so they were much more densely spaced than in their final configuration. Using two 18.5 meter microwave dish antennae, Project West Ford engineers managed to send voice transmissions between Camp Parks, California and Millstone Hill, Massachusetts. The voice connection was described as "intelligible" and was transmitted at a data rate of approximately 20,000 bits per second– about the speed of a 1992-era telephone modem. But as the needles continued to disperse to their final cloud, the data rate dropped off significantly, so much so that by June 18th only 400 bits per second could be transmitted. On July 2nd, the experiment was terminated. At this time, the tiny needles were spaced about 400 meters from each other.

westford_antenna.jpg Despite its technical success, the ultimate goal behind Project West Ford was never attained. Serious scientific opposition to the project sprung up almost immediately after it was first proposed in the late 1950s. Though West Ford's cloud of dipoles was carefully designed to return to Earth within a few years of its launch, a fully-functional cloud dense enough for robust communications might be a permanent fixture of Earth's orbit.

Because of the great distance between the tiny needles, the West Ford belt was visible only in the first few days after launch when the spacing was much smaller. A denser belt intended for permanent communications would probably not have been visible except by very powerful optical telescopes. But, at radio and microwave frequencies, the final dipole clouds may have become scars on the night sky, forever obscuring the universe beyond.

However, it may not have been the opposition from prominent scientists that finally killed Project West Ford's dream. By 1963, communications satellite technology had become more and more capable. Compared to those sleek products of Space Age technology, the relatively low-tech West Ford dipole cloud was an unsightly dinosaur. However, the West Ford engineers remained convinced of the feasibility of their endeavour, and largely blamed the end of the program on the opposing scientists rather than flaws in their own technology.

Most of the West Ford dipoles re-entered Earth's atmosphere sometime around 1970, according to theoretical and observational evidence. The needles slowly drifted down to the Earth's surface, unscathed by re-entry because of their size. Some consideration was given to recovering one or more of the dipoles in order to learn more about the space environment. Calculations showed that as many as five dipoles would have landed per square kilometer in the high Arctic. But the exceptional cost of recovering these tiny needles from the haystack of billions of tons of Arctic snow killed off any practical attempts at recovery. Back in space, the failed 1971 1961 spacecraft and some larger clumps of the 1973 1963 dipoles remain in orbit like so many other pieces of space junk, silently carrying the long-dead hopes of this nearly forgotten experiment.

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If the full moon tonight looks unusually large, it is not your imagination – it is the biggest and brightest full moon to be seen for 15 years.

Each month the Moon makes a full orbit around the Earth in a slightly oval-shaped path, and tonight it will swing by the Earth at its closest distance, or perigee. It will pass by 356,613km (221,595 miles) away, which is about 28,000km closer than average.

The unusual feature of tonight is that the perigee also coincides with a full moon, which will make it appear 14 per cent bigger and some 30 per cent brighter than most full moons this year – so long as the clouds hold off from blocking the view.

In addition to this lunar flypast, much of Britain may also be treated to a strange phenomenon known as the moon illusion. As the Moon rises in the late afternoon, it will appear even larger as it lies close to the horizon. Psychologists have tried to explain this as a trick of the eye, as the landscape on the horizon appears to make the Moon loom much larger, an effect that disappears as the Moon rises above the horizon, although viewing it through a tube, such as a toilet roll, can make it look large again.

With the Moon approaching so close to the Earth, its gravity will pull a slightly higher tide than normal for a full moon. This so-called perigeal tide adds about 0.5m (1.6ft) to the high-water mark, and with freshening southwesterly winds forecast, this may cause some flooding, especially along parts of the South West coast.

Tonight’s full moon is also notable for rising to its greatest height in the night sky for the entire year, lying almost overhead at midnight. This is because we are approaching the winter solstice, on December 21, and thanks to the tilt of the Earth the Moon appears at its highest, as the Sun is at its lowest.

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Another astronomical treat that could be seen tonight and for the next two nights is the annual Geminid meteor shower, one of the year’s best displays of shooting stars. Up to 100 meteors an hour can fly across the sky. The meteors, which are easy to spot with the naked eye, appear to shoot out from the constellation Gemini, hence their name, but they can be seen all over the sky. However, with a full moon so bright, the best place to look is away from the Moon.

Meteor showers happen when the Earth passes through clouds of debris shed from comets. As the tiny fragments smash into the Earth’s upper atmosphere at about 100,000mph, they burn up in streaks of light.

For reasons that are not understood, the Geminid meteor showers are tending to grow stronger each year.

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The sky down here has been incredibly clear lately, making viewing of heavenly bodies, even with the naked eye, fantastic. The recent combination of the crescent moon, Jupiter, and Saturn was amazing - very bright and crystal clear. The nearly full moon last night was brilliant - it illuminated our entire house, reflected down into the pool, and made walking on paths outside possible - even late at night.

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Well, Friday night, I looked up at the Moon, and this noght there were some clouds in the area.....

What was special about tonoght's viewing was the large cloud circle around the moon....

THat was nice to look at......

But still, the brillance of the Moon around midnight Thursday evening was something !

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A book that I would highly recommend to any amatuer or advanced astronomer is "Horizens". the auther, Michael Seeds is unequaled in his ability to deliver information. Any of his books are going to give you some great knowledge. I have to dig up mine. It has astronomical charts of the night sky based on the time of year. Masses and make up of planets. Methods of determining the distance to planets and stars. Defining stars. Young stars which are blue or white stars as opposed to old stars that are red/orange and breaking up. Good info on time and distance, measured in what is know to be an astronomical unit. Distance in outer space is measured in astronomical units. One astronomical unit is the distance from the earth to the sun. Once you have a grasp of time and distance, you will be far more likely to believe that there is probably other life out there. Whether intellligent or not. But you will be far more skeptical as to whether we have been visited by these UFO's. For us to reach an inhabited planet we would have to reproduce on the space ship. We have some very good ideas to reach speeds that so far we have only been ablel to dream of . One such idea involves increased acceleration with a type of domino effect. But there would be many risks. Asteroids for instance that could instantly obliterate the ship. Astronomy is a fascinating subject. So too is oceanography. So anyway, if you have the interest go to a library and take out some books by Seeds. You will not be disappointed.

Thanks for you recommendation. I think I will try to get it if I ever get a chance.

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On 3/14/2015 at 6:00 PM, luvlz2 said:

A short video about what would life on Europa would look like https://youtu.be/lZo7_bR7V4U

Before I watch this, for one thing, I studied Astronomy.  For another thing, I have heard talk of Europa before.  But there is no solid evidence of any life.  So what is this all about?  Conjecture?  Speculation?  I think so.  

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