sky-gazers delight

[Linville]

Skygazers prepare for rare Mercury sighting



Paris (AFP) - Earthlings will witness Mercury make a rare passage between our planet and the Sun on Monday, appearing as a black dot tracking the surface of the star we share with the solar system's smallest planet.
Mercury completes an orbit every 88 days, and passes between the Earth and the Sun every 116 days, according to the Royal Astronomical Society (RAS).
But its orbit is tilted in relation to Earth's, which means it usually appears -- from our perspective -- to pass above or below the Sun.
Thirteen times each century, however, the two orbits align such that even amateur astronomers can see the tiny planet tens of millions of kilometres away.
"It is always exciting to see rare astronomical phenomena such as this transit of Mercury," RAS president Martin Barstow said in a statement.
"They show that astronomy is a science that is accessible to everyone."
But be warned: looking directly at the phenomenon can result in permanent eye damage, as only a very small part of the Sun will be blocked out.
One option is to use a telescope or binoculars to project the image onto a white surface.
An image of the Sun is captured by the main, front lens and projected backward, out through the eyepiece. The Sun will appear as a white disk on the card, and Mercury as a black dot crawling over it.
Stargazers can also observe the event through a telescope with a strong filter.
According to the RAS, large parts of the world -- most of Western Europe, the western parts of North and West Africa, eastern North America, and most of South America -- will be able to view the entire transit, which will last from 1112 GMT to 1842 GMT.
The rest of north and south America, the eastern Pacific, the remainder of Africa and most of Asia, will see parts of the event.
Observers in east and southeast Asia and Australasia, however, will miss out entirely.
French astronomer Pierre Gassendi was the first person to observe a Mercury transit through a telescope in 1631, two decades after the instrument was invented.
German astronomer Johannes Kepler had correctly predicted that transit, but died in 1630 before he could witness the event.
The last Mercury orbit was 10 years ago, and the next will be in 2019.
Mercury is the planet nearest to the Sun. Its elliptical orbit brings it as close to the earth as 46 million kilometres (28.5 million miles), and no further away than 70 million kilometres.
It rotates so slowly -- three times for every two orbits -- that, bizarrely, Mercury's day is twice as long as its year.

[Linville]

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[Linville]

More on same....Monday May 9 is the day remember.

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Mercury is about to make a rare journey across the face of the sun





The planet Mercury is about to throw some shade at Earth.

For about seven hours on Monday, May 9, the innermost planet will trek across the face of the sun and cast a shadow on our planet. During its journey, a rare event known as a transit, Mercury will appear as a tiny black speck on the sun. 

The transit will begin at 7:12 a.m. Eastern Daylight Time and end at 2:42 p.m. It will be visible from most countries, though folks in Japan, Australia, New Zealand, and islands in the West Pacific are out of luck.

Transits of Mercury happen on average about eight times a century and only in May or November. The last one was in 2006; the next one won’t be until 2019.

Don’t stare at the sun to try and see it. Seriously. Don’t do that. Staring at the sun is dangerous. Plus, Mercury is tiny. A solar-filtered telescope with at least 50x magnification is the best and safest way to enjoy the show. 

Many astronomy clubs and organizations will have viewing events. And there will be many ways to see it online such as NASA TV, the Virtual Telescope Project and the Slooh Observatory. 

[Linville]

Watch Mercury Sail Across the Sun





On Monday, you can watch Mercury sail across the sun.

It’s an astronomical event known as the Mercury transit, and it occurs about a dozen times a century.

During the trip, the planet will appear as a black speck awash in the sun’s light. You can track its celestial silhouette for about seven hours, starting around 7:12 a.m. Eastern and ending around 2:42 p.m.

Depending on the weather, it should be visible from most parts of the world, except for Australia, New Zealand and parts of East Asia.

The best way to view it is through a telescope or on several live streams, but don’t try to sneak a peak with your naked eye or camera phone because that could damage your sight.

Jim Green, the director for planetary science at NASA, said that ever since the telescope was invented some 400 years ago, astronomers had used the transit to gain important details about Mercury’s size, orbit and atmosphere.



https://www.youtube.com/embed/K5dWNk5XAv...ransparent


View of 2006 Mercury Transit Video by NASA.gov Video
“This phenomena that we see in our own solar system, we’re using those same basic principles to find planets around other stars,” he said.

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The Kepler spacecraft has recorded 3,000 to 4,000 planetary transits. It has used that information to identify 1,041 exoplanets. Dr. Green said that based on that information, there appeared to be more planets than stars in our galaxy.

During Monday’s event, solar physicists at NASA will have their high-powered telescopes fixed on Mercury’s edge, where it looks as if the planet ends and the sunlight begins.

“It’s that location where we will see the very tenuous atmosphere of Mercury called an exosphere,” Dr. Green said. They want to gain a better understanding of the sodium that its exosphere emits, he said.

“Mercury Transit is a pretty fantastic event,” added Dr. Green, who first saw the spectacle on May 9, 1970. “It’s one of those things that allow us to keep learning and discovering things not only in our solar system but also in the galaxy.”