transit of Venus between the Sun and Earth

The transits of Venus, visible in Central America and North America and will continue to Europe, is a unique opportunity for science but also to human curiosity, say experts.

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“Essentially it’s an eclipse, the interesting thing that happens every hundred years,” said Eduardo Araujo, a scientist at the National Oceanic and Atmospheric Administration (NOAA).

“The planet passes between Earth and Sun and looks like a small point that the Sun travels,” he said.

The distance is so great that it has no effect on the earth but it is a “great opportunity” for scientists to study the wavy motion, gravitational forces, density, and many aspects as possible.

Now begins the collection of data, the results will not be immediately, studies will be completed in months and present the first findings.

“It’s an opportunity from the standpoint of the scientific world and from the point of view of human curiosity is unique too,” said Araujo, who recalled that not all generations have the opportunity to see a transition.

Transits of Venus are rare, occur in pairs eight years apart and then not recur over a hundred years later. The last was 2004 and after this, that completes the pair, experts estimate that there will be another until 2117.

NASA planned to begin at 22:09 GMT and is expected to have a duration of seven hours.

The entry is expected to occur between 22:09 and 22:27 GMT on June 5 and depart between 4:32 and 04:50 GMT.

Araujo encouraged to participate in any activity that NASA centers, planetariums and scientific organizations have been organized throughout the world to see this unique spectacle.

Although, recalled that it must be done with caution and “never look at the sun with the naked eye” because it can cause anything from eye injuries or even blindness in severe cases.

Experts recommend looking through telescopes or special glasses prepared, never with normal sunglasses.

Transits of Venus captured public attention in the eighteenth century, when the size of the solar system was one of the greatest mysteries of science, NASA recalls in an article.

The relative distance of the planets was known but not their absolute distances-how many miles between us and another possible world, and Venus was the key, according to astronomer Edmund Halley deduced (1656-1742).

Halley found that observing the transit from various places on Earth, it should be possible to triangulate the distance to Venus, prompting international expeditions to survey the transits occurred in 1761 and 1769.

Other split the explorer James Cook, who was sent to Tahiti in French Polynesia today in an effort that some historians have called “the Apollo program of the eighteenth century.”

NASA says that the experiment, in retrospect, it sounded better than it was the result, because the bad weather in some places of observation and the limitations of primitive instruments caused “confusion” on the actual density of the atmosphere of Venus and other data.

A late nineteenth century, astronomers, with modern instruments and cameras, finally managed to measure the size of the solar system as Halley had suggested to the data of registered transits in 1874 and 1882.

Now scientists at the twenty-first century, with satellites in space and better cameras than ever, hoping to study hundreds of phenomena as the behavior of extra solar planets in the search for life in the universe.

Nasa survey 4,700 potentially hazardous asteroids, plus or minus 1,500 space rocks

A new NASA survey has pinned down the number of asteroids that could pose a collision threat to Earth in what scientists say is the best estimate yet of the potentially dangerous space rocks.

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The survey found there are likely 4,700 potentially hazardous asteroids, plus or minus 1,500 space rocks, that are larger than 330 feet (100 meters) wide and in orbits that occasionally bring them close enough to Earth to pose a concern, researchers said. To date, only about 30 percent of those objects have actually been found, they added.

Potentially hazardous asteroids, or PHAs in NASA-speak, are space rocks in orbits that come within 5 million miles (8 million kilometers) of Earth and are large enough to cause damage on regional or global scale if they were ever to hit our planet.

The new study was based on observations from NASA’s Wide-field Infrared Survey Explorer (WISE), an infrared space telescope. While the telescope data returned an estimate of the potentially dangerous near-Earth asteroid population that is similar to previous projections, it also revealed some surprising new results.

According to the survey, about twice as many asteroids are in so-called “lower-inclination orbits” — which are more closely aligned with Earth’s path around the sun than other objects — than previously thought researchers said. [Video: WISE Telescope’s Asteroid Census]

Elektro-L satellite takes pictures of our planet in Staionary view

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MEXICO CITY, The Elektro-L satellite that takes pictures of the planet is held stationary over the Indian Ocean orbiting 40,000 kilometers above the Earth.

The fantastic cameras technology placed in the satellite creates a 121 megapixel image every 30 minutes with four wavelengths of visible light and infrared.

The infrared light orange color that appears in these pictures shows the vegetation.

The images were captured from May 14, 2011 and end on May 20.

Images are the largest of our planet with a resolution of 1 kilometer per pixel.

Sun seems to have weaker interaction with the rest of the galaxy

It is too early to say exactly what this new data means for the heliosphere.

A diagram depicting Voyager 1 at its relative ...

A diagram depicting Voyager 1 at its relative position in the heliosheath. Since then, Voyager 2 has joined it in the heliosheath. (Photo credit: Wikipedia)

Seems to have a weaker interaction with the rest of the galaxyThe relative motion of the Sun with respect to the interstellar medium is slower than previously thought

The sun moves through interstellar space more slowly than previously thought and time seems to have a weaker interaction with the rest of the galaxy, according to a study released today in the journal Science.

The engineer David McComas of the Southwest Research Institute, University of Texas, and his team have confirmed that the relative motion of the Sun with respect to the interstellar medium is slower than previously thought. The team used new measurements the Interstellar Boundary Explorer (IBEX, for its acronym in English) spacecraft, a small spacecraft remotely images generated by the interaction of particles at the edge of our solar system and helps researchers determine the exact position of solar system in the galaxy.

The solar system is moving rapidly through space, traveling in a bubble of solar wind and magnetic field called the heliosphere. The boundary of the heliosphere where the solar wind interacts with the rest of the galaxy, marks the edge of the solar system, known as the interstellar boundary region. But new findings show that the Sun IBEX moves so slow that the pressure of material that flows around the heliosphere is 25% lower than expected, for what they believe is not enough to create a bow shock, a structural component that is believed to control the flow of cosmic rays of high energy.

“The Sonic boom by a plane breaking the sound barrier is an example of a terrestrial bow shock, “says McComas, principal investigator of the IBEX mission. “As the jet reaches supersonic speeds, the air in front of it cannot get fast enough “and” once the aircraft reaches the speed of sound, interaction changes occur instantly become a shock wave.”

The finding suggests that the protective boundary that separates our solar system from the rest of the galaxy lacks the bow shock, as stated in scientific theories, and could have implications on how much radiation (in the form of galactic cosmic rays) coming into our solar system.

For about a quarter of a century, researchers believed that the heliosphere is moving through the interstellar medium at a rate fast enough to form a bow shock. However, data have shown that IBEX heliosphere actually moves through the local interstellar cloud at about 83,685 kilometers per hour, about 11,200 kilometers an hour slower than previously thought. This represents a rate slow enough to create more of a “wave” than a “bow” shock. “While it is true that there are bow shocks by many other stars, we believe that the interaction of our sun does not reach the critical threshold to form a shock, so that a wave is a more accurate representation of what is passing in front of our heliosphere, as well as that made by the bow wave of a boat that glides across the water, “said McComas.

He noted that “it is too early to say exactly what these new data mean for our heliosphere.” He said you have to develop new research using these data, since the change in the way that galactic cosmic rays enter the solar system is important for space travel.