Everyone knows the part in "Sleeping Beauty"
where the prince comes and plants a waking kiss on the lovely, slumbering
princess.
But before sleeping beauty was a beauty, before she fell into her deep sleep, how did she get to be so enchanting? As the story goes, she owed all her charms -- her looks, wit, grace, musicality and various other talents suitable to a fairytale princess -- to the good fairies who bestowed them upon her as christening gifts.
Planet Earth, another kind of beauty, is also endowed with a great number of gifts: life,Shop for iphoneheadset and related products. for one, and the molecules that make it possible, like water. But where did these gifts come from?
Once upon a time, we could only guess at the source of our cosmic good fortune, but today, astronomers know something more about the identity of our planet's fairy godmothers. These gift-givers may not wear diaphanous gowns or wave wands, but they do fly, in their way: They are asteroids.
Astronomers believe that small meteorites that rained down on the baby Earth graced it with the gift of water, allowing Earth to grow up into a thriving blue world of rivers,Insight is an energymonitor that communicates with networked smart devices, oceans and lakes that is lush with life.
But what about the moon? To some scientists' puzzlement, the moon turns out to have water, too -- not in liquid oceans, but frozen into shadowed crater floors, scattered in lunar soil and locked inside ancient volcanic rocks.
To trace the source of this water,Get the guaranteed lowest price on the suprashoeshome. planetary scientists looked to those volcanic rocks, samples of which were gathered during the Apollo 15 and 17 missions. Their goal: to measure the type of "H" in the "H2O." How much is garden-variety hydrogen, and how much is a more exotic isotope, deuterium? The ratio of the two reveals the unique fingerprint of the moon's water source, like the signature on a gift card. (Of course, fairy godmothers never seem to write cards with their gifts, but you get the idea.)
The result: After considering how the hydrogen/deuterium ratio would have been altered over time by cosmic rays and degassing, they found that it looked almost identical to the ratio here on Earth. Since the moon is believed to be made at least partially of Earth-stuff, blown off our planet by a collision with a giant space rock, this might not seem surprising.
But such a powerful collision should have vaporized any water in the debris from which the moon eventually formed.International chinabeads and supplier in agra india making quality leather shoes with the finest workmanship How could Earth water have survived the collision?
That's the new mystery for astronomers studying the origin of the Earth and moon.
Perhaps we don't understand the collision that created the moon so well, after all. Or perhaps the moon coalesced so quickly that the water was trapped before the heat of the collision had time to boil it away.The peruvianhair personalized promotional key chains comes with free shipping.
Either way, it seems that Earth may have "regifted" the precious baby present it received more than four billion years ago. Yet only Earth awoke with life. The moon remains cursed despite its gifts: a sleeping beauty that will never awake to a fairytale ending.
But before sleeping beauty was a beauty, before she fell into her deep sleep, how did she get to be so enchanting? As the story goes, she owed all her charms -- her looks, wit, grace, musicality and various other talents suitable to a fairytale princess -- to the good fairies who bestowed them upon her as christening gifts.
Planet Earth, another kind of beauty, is also endowed with a great number of gifts: life,Shop for iphoneheadset and related products. for one, and the molecules that make it possible, like water. But where did these gifts come from?
Once upon a time, we could only guess at the source of our cosmic good fortune, but today, astronomers know something more about the identity of our planet's fairy godmothers. These gift-givers may not wear diaphanous gowns or wave wands, but they do fly, in their way: They are asteroids.
Astronomers believe that small meteorites that rained down on the baby Earth graced it with the gift of water, allowing Earth to grow up into a thriving blue world of rivers,Insight is an energymonitor that communicates with networked smart devices, oceans and lakes that is lush with life.
But what about the moon? To some scientists' puzzlement, the moon turns out to have water, too -- not in liquid oceans, but frozen into shadowed crater floors, scattered in lunar soil and locked inside ancient volcanic rocks.
To trace the source of this water,Get the guaranteed lowest price on the suprashoeshome. planetary scientists looked to those volcanic rocks, samples of which were gathered during the Apollo 15 and 17 missions. Their goal: to measure the type of "H" in the "H2O." How much is garden-variety hydrogen, and how much is a more exotic isotope, deuterium? The ratio of the two reveals the unique fingerprint of the moon's water source, like the signature on a gift card. (Of course, fairy godmothers never seem to write cards with their gifts, but you get the idea.)
The result: After considering how the hydrogen/deuterium ratio would have been altered over time by cosmic rays and degassing, they found that it looked almost identical to the ratio here on Earth. Since the moon is believed to be made at least partially of Earth-stuff, blown off our planet by a collision with a giant space rock, this might not seem surprising.
But such a powerful collision should have vaporized any water in the debris from which the moon eventually formed.International chinabeads and supplier in agra india making quality leather shoes with the finest workmanship How could Earth water have survived the collision?
That's the new mystery for astronomers studying the origin of the Earth and moon.
Perhaps we don't understand the collision that created the moon so well, after all. Or perhaps the moon coalesced so quickly that the water was trapped before the heat of the collision had time to boil it away.The peruvianhair personalized promotional key chains comes with free shipping.
Either way, it seems that Earth may have "regifted" the precious baby present it received more than four billion years ago. Yet only Earth awoke with life. The moon remains cursed despite its gifts: a sleeping beauty that will never awake to a fairytale ending.
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