02Mar2012

The Moon Has A Dark Side

The two distinct facets of our Moon are easily seen in this amazingly clear half moon shot.

Look tonight and go find our glorious moon. The moon’s disc is about 50 percent illuminated (at time of writing) by sunshine and 50 percent engulfed in its own shadow. This is what we commonly call ‘Half Moon.’  Half the moon is always illuminated in space. In other words, the moon has a day side and a night side, just as Earth does.

Due to the angle between the sun, Earth and moon tonight, we’re seeing equal portions of the moon’s day side and night side. The part of the moon that isn’t in sunlight is often called the moon’s dark side. Just realize that – because of the moon’s motion around Earth – the portion of the dark side that we see from Earth constantly changes.

There is a permanent far side of the moon. But there is no permanent dark side of the moon, because any given lunar location experiences night for about two weeks, followed by daylight for about two weeks.

The moon does rotate on its axis. But billions of years of Earth’s strong gravitational pull have slowed it down such that today the moon takes as long to rotate as it does to orbit once around Earth. Astronomers would say that the moon is tidally locked with Earth. For that reason, one side of the moon always faces Earth, but it is not always dark – as you can see just by looking at the sky tonight.

Incidentally, the moon’s gravitational effects on Earth are much smaller, but – given billions of years of time – the Earth will slow down and keep one face always toward the moon. Look for the half Moon from where you live.

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Moon Rocks Lost In Dump

It may be a case of sheer, unadulterated "lunar-cy", but an out of this world find worth as much as €4m could be buried in one of the country’s largest rubbish dumps.

A new investigation into the disappearance of 184 moon rock segments from the US Apollo 11 and 17 missions 43 and 40 years ago has claimed one of the valuable items may be lost inside Dublin’s Dunsink dump — a facility better known as a graveyard for useless items and used nappies. 

The BBC has reported that, as part of a major public relations exercise, then president Richard Nixon sent pieces of the rocks to all US states and 135 foreign nations, including Ireland, following the return of what would be the final moon landing mission. 

A piece of the Irish rock was placed in the Dunsink Observatory for safe-keeping. However, after a serious fire destroyed the facility on Oct 3, 1977, the item was lost. 

While other segments are also based at the Natural History Museum and UCD’s Geology Department, on loan from Nasa, it is now believed the missing Dunsink piece may be hidden beneath almost four decades of rubbish. 

And although the item itself is small, the fact previous segments have gone on sale for prices between tens of thousands of euro and €3.8m has led to significant interest in the claim. 

The BBC revelation is based on the views of Dr Ian Elliot, who worked at observatory at the time of the 1977 fire and said “it was gathered up with all of the other debris and dumped in the municipal dump, which was conveniently just across the road”. 

“It was only afterwards that we realised that the bit of moon rock could not be found. If we’d had any perception of the rock’s value, perhaps all of the debris would have been sifted by archaeologists and it might have been found. 

“It is a very big dump, I am afraid. It is worse than a needle in a haystack — you would never find it,” he said. 

While former Nasa agent and Texas-based lawyer, Joseph Gunthienz Junior, supports the story, stating that the Dunsink moon rock “is under a couple of tonnes of trash”, the actual value of the item has been questioned. 

Different sized moon rocks from Honduras and Russia have previously been offered for sale to black market collectors for between €280,000 and €3.8m — with admittedly varying degrees of success. 

However, Tom Ray, professor in astrophysics at the Dublin Institute for Advanced Studies, said would-be rubbish hunters should not expect a similar windfall. 

“I saw the Apollo rock a long time ago at the observatory… The chances of recovering it after the fire were zilch. It is a tiny spec,” he said. Source: Before Its News