New View of Mercury

 January 16, 2008—The first of many planned images from NASA's MESSENGER spacecraft is showing astronomers a side of Mercury no one's ever seen before.

Mercury is tough to view from Earth, since it's so close to the sun. And when the Mariner 10 probe flew past the innermost planet in 1974 and 1975, only one side of the body was facing sunlight.

That's because Mercury rotates three times during every two orbits, so the same side of the planet is lit up every other time it is nearest to the sun—including during all of Mariner's flybys.

Added up, these factors have meant that although Mercury sits only about 57 million miles (92 million kilometers) away from Earth, for more than 30 years scientists have had almost no details about its other face.

But on Monday MESSENGER, the first mission to Mercury since the 1970s, snapped the first image of the "missing" half of the rocky world.

Among many new sights, the picture features the full Caloris Basin, a huge impact basin more than 620 miles (1,000 kilometers) across that sits on the border between the known and previously unknown regions of the planet.

More unprecedented images of the tiny planet are expected as the MESSENGER craft completes three flybys of Mercury before settling into orbit in March 2011.

From that point on, writes astronomer Phil Plait on the Bad Astronomy blog, "we'll get as many images of this tiny, hot, battered, dense and neglected planet as we can handle."

—Victoria Jaggard

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http://news.nationalgeographic.com/news/2008/01/080116-mercury-first.html

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Astro News..more about Mercury and it's retrograde cycle 

excerpt:

Stay alert. Whatever has been stewing and brewing over these past few months will not only surface, it will rapidly escalate once Mars is unleashed; its retrograde cycle completes as of Jan 30, just after a showy Full Moon (Jan 22), a momentous first taste of Pluto in Capricorn (entering the sign on Jan 26) and the start of Mercury’s retrograde cycle (Jan 28 – Feb 18.)

The very potent Solar Eclipse on Feb 6 can ignite fabulous opportunity for some, or utter chaos for others. Watch for the unexpected, perhaps even the shocking.

Keep your eyes on the US candidate’s election Feb 5, which takes place the day before the new moon solar eclipse.

It’s a wild card race, but perhaps in the end perhaps the results may not be so surprising. (Chiron and Mercury retrograde involved in this eclipse, suggests there are flaws or “ya, buts” in all the runners of the race.)

Feb 6 is also the start of the Chinese Year of the Rat (charismatic, ambitious and opportunistic.)