The moon—an object of wonder since the dawn of mankind. It lights up the night sky like nothing else in the heavens, and appears as if it regularly changes shape. As we shall see, it is well designed for life on Earth, while its origin baffles evolutionists.
The moon’s origin
The answer’s in Genesis! A major purpose is to light up the night. The moon reflects the sun’s light on to us even when the sun is on the other side of the earth. The amount of reflected light depends on the moon’s surface area, so we are fortunate to have a moon that is so large. It is over a quarter of Earth’s diameter — far larger in comparison with its planet than any other in the solar system.1 Also, if it were much smaller, it would not have enough gravity to maintain its spherical shape.2
Another reason for the moon is to show the seasons. The moon orbits the earth roughly once a month causing regular phases in a 29½ day cycle (see diagram below). So calendars could be made, so people could plant their crops at the best time of the year.
An important feature is that the moon always keeps the same face towards the earth.3 If different parts were visible at different times, the moon’s brightness would depend on which part was pointing towards the earth. Then the 29½ day cycle would be far less obvious.
Tides
The earth’s gravity keeps the moon in orbit, and is so strong that it would need a steel cable 850 km (531 miles) in diameter to provide an equivalent binding force without breaking. The moon exerts the same force on the earth. But the force is somewhat higher on the part of the earth nearest the moon, so any water there will bulge towards it — a high tide. The part furthest from the moon is attracted the least by the moon, so flows away from the moon (and Earth’s centre) — another high tide on the opposite side of the earth. In between, the water level must drop — the low tides — see diagram below. As the moon orbits the spinning earth, there is a cycle of two high tides and two low tides about every 25 hours.
Tides are vital to life on Earth. Tides cleanse the ocean’s shorelines, and help keep the ocean currents circulating, preventing the ocean from stagnating. They benefit man by scouring out shipping channels and diluting sewage discharges. In some places, people exploit the enormous energy of the tides to generate electricity.4
The Apollo moon landing. Such achievements may be a logical extension of the dominion mandate given to mankind in Genesis 1:28. The moon’s utter barrenness should remind us of our planet’s unique design for life.
Nice to visit; but to live?
One of the most dramatic events of our time was the landing of men on the moon. However, they confirmed that it is a lifeless, airless world, with huge temperature extremes and no liquid water. From the moon, Earth appears as a bright blue-and-white object in the black sky. Earth is the planet God has designed for life. Man may be able to live on other worlds one day, but it will be hard to make them habitable.
Many people don’t realise that the man behind the Apollo moon mission was the creationist rocket scientist Wernher von Braun.5 And another creationist, Jules Poirier, designed some vital navigational equipment used in the space program.6
How long has the moon been receding?
The moon is a good example of the heavens declaring God’s glory (Psalm 19:1). It does what it’s designed to do, and is vital for life on Earth. It is also a headache for evolutionists/uniformitarians.
Tuesday, March 25, 2008
Tuesday, March 18, 2008
The mooN
The Moon, of course, has been known since prehistoric times. It is the second brightest object in the sky after the Sun. As the Moon orbits around the Earth once per month, the angle between the Earth, the Moon and the Sun changes; we see this as the cycle of the Moon's phases. The time between successive new moons is 29.5 days (709 hours), slightly different from the Moon's orbital period (measured against the stars) since the Earth moves a significant distance in its orbit around the Sun in that time.
Due to its size and composition, the Moon is sometimes classified as a terrestrial "planet" along with Mercury, Venus, Earth and Mars.
The Moon was first visited by the Soviet spacecraft Luna 2 in 1959. It is the only extraterrestrial body to have been visited by humans. The first landing was on July 20, 1969 (do you remember where you were?); the last was in December 1972. The Moon is also the only body from which samples have been returned to Earth. In the summer of 1994, the Moon was very extensively mapped by the little spacecraft Clementine and again in 1999 by Lunar Prospector.
The gravitational forces between the Earth and the Moon cause some interesting effects. The most obvious is the tides. The Moon's gravitational attraction is stronger on the side of the Earth nearest to the Moon and weaker on the opposite side. Since the Earth, and particularly the oceans, is not perfectly rigid it is stretched out along the line toward the Moon. From our perspective on the Earth's surface we see two small bulges, one in the direction of the Moon and one directly opposite. The effect is much stronger in the ocean water than in the solid crust so the water bulges are higher. And because the Earth rotates much faster than the Moon moves in its orbit, the bulges move around the Earth about once a day giving two high tides per day. (This is a greatly simplified model; actual tides, especially near the coasts, are much more complicated.)
But the Earth is not completely fluid, either. The Earth's rotation carries the Earth's bulges slightly ahead of the point directly beneath the Moon. This means that the force between the Earth and the Moon is not exactly along the line between their centers producing a torque on the Earth and an accelerating force on the Moon. This causes a net transfer of rotational energy from the Earth to the Moon, slowing down the Earth's rotation by about 1.5 milliseconds/century and raising the Moon into a higher orbit by about 3.8 centimeters per year. (The opposite effect happens to satellites with unusual orbits such as Phobos and Triton).
The asymmetric nature of this gravitational interaction is also responsible for the fact that the Moon rotates synchronously, i.e. it is locked in phase with its orbit so that the same side is always facing toward the Earth. Just as the Earth's rotation is now being slowed by the Moon's influence so in the distant past the Moon's rotation was slowed by the action of the Earth, but in that case the effect was much stronger. When the Moon's rotation rate was slowed to match its orbital period (such that the bulge always faced toward the Earth) there was no longer an off-center torque on the Moon and a stable situation was achieved. The same thing has happened to most of the other satellites in the solar system. Eventually, the Earth's rotation will be slowed to match the Moon's period, too, as is the case with Pluto and Charon.
Actually, the Moon appears to wobble a bit (due to its slightly non-circular orbit) so that a few degrees of the far side can be seen from time to time, but the majority of the far side (left) was completely unknown until the Soviet spacecraft Luna 3 photographed it in 1959. (Note: there is no "dark side" of the Moon; all parts of the Moon get sunlight half the time (except for a few deep craters near the poles). Some uses of the term "dark side" in the past may have referred to the far side as "dark" in the sense of "unknown" (eg "darkest Africa") but even that meaning is no longer valid today!)
The Moon has no atmosphere. But evidence from Clementine suggested that there may be water ice in some deep craters near the Moon's south pole which are permanently shaded. This has now been reinforced by data from Lunar Prospector. There is apparently ice at the north pole as well. A final determination will probably come
One of a number of disks used by NASA to promote public understanding of the Moon.Samples of moon rocks and moon soil are embedded in a clear plastic disk for convenient viewing.
The Earth and Moon as seen by the NEAR spacecraft, as it passed beneath their South poles (note Antarctica, at center Earth image) in January of 1998. As dark as the Moon appears in comparison to the Earth, it is actually five times darker yet, as its brightness was enhanced by that much in creating this picture. (NEAR Spacecraft Team, JHUAPL, NASA, apod980129)
The Moon's distance from the Earth changes by 6% from its average distance as it moves toward perigee, or apogee. As a result, the apparent size increases or decreases by 6%, as well. These images show the apparent size of the Moon at apogee (on the left), and at perigee (on the right). (The change in size is not so obvious when the time between the extremes is two weeks, as when images are placed side by side.) When
Modern Definition:
A Blue Moon is commonly the name given to the second full moon in a month. Since a full moon occurs every 29 1/2 days, if there is a full moon on the 1st or 2nd day of a month, there is a good chance there will be a second full or blue moon that month.
In 1999, there were two blue moons very close together. One on January 31st (after the full moon on Jan. 2nd) and the other on March 31st (after the full moon on March 2nd).
There was another in November 2001, but not again until July 2004.
Due to its size and composition, the Moon is sometimes classified as a terrestrial "planet" along with Mercury, Venus, Earth and Mars.
The Moon was first visited by the Soviet spacecraft Luna 2 in 1959. It is the only extraterrestrial body to have been visited by humans. The first landing was on July 20, 1969 (do you remember where you were?); the last was in December 1972. The Moon is also the only body from which samples have been returned to Earth. In the summer of 1994, the Moon was very extensively mapped by the little spacecraft Clementine and again in 1999 by Lunar Prospector.
The gravitational forces between the Earth and the Moon cause some interesting effects. The most obvious is the tides. The Moon's gravitational attraction is stronger on the side of the Earth nearest to the Moon and weaker on the opposite side. Since the Earth, and particularly the oceans, is not perfectly rigid it is stretched out along the line toward the Moon. From our perspective on the Earth's surface we see two small bulges, one in the direction of the Moon and one directly opposite. The effect is much stronger in the ocean water than in the solid crust so the water bulges are higher. And because the Earth rotates much faster than the Moon moves in its orbit, the bulges move around the Earth about once a day giving two high tides per day. (This is a greatly simplified model; actual tides, especially near the coasts, are much more complicated.)
But the Earth is not completely fluid, either. The Earth's rotation carries the Earth's bulges slightly ahead of the point directly beneath the Moon. This means that the force between the Earth and the Moon is not exactly along the line between their centers producing a torque on the Earth and an accelerating force on the Moon. This causes a net transfer of rotational energy from the Earth to the Moon, slowing down the Earth's rotation by about 1.5 milliseconds/century and raising the Moon into a higher orbit by about 3.8 centimeters per year. (The opposite effect happens to satellites with unusual orbits such as Phobos and Triton).
The asymmetric nature of this gravitational interaction is also responsible for the fact that the Moon rotates synchronously, i.e. it is locked in phase with its orbit so that the same side is always facing toward the Earth. Just as the Earth's rotation is now being slowed by the Moon's influence so in the distant past the Moon's rotation was slowed by the action of the Earth, but in that case the effect was much stronger. When the Moon's rotation rate was slowed to match its orbital period (such that the bulge always faced toward the Earth) there was no longer an off-center torque on the Moon and a stable situation was achieved. The same thing has happened to most of the other satellites in the solar system. Eventually, the Earth's rotation will be slowed to match the Moon's period, too, as is the case with Pluto and Charon.
Actually, the Moon appears to wobble a bit (due to its slightly non-circular orbit) so that a few degrees of the far side can be seen from time to time, but the majority of the far side (left) was completely unknown until the Soviet spacecraft Luna 3 photographed it in 1959. (Note: there is no "dark side" of the Moon; all parts of the Moon get sunlight half the time (except for a few deep craters near the poles). Some uses of the term "dark side" in the past may have referred to the far side as "dark" in the sense of "unknown" (eg "darkest Africa") but even that meaning is no longer valid today!)
The Moon has no atmosphere. But evidence from Clementine suggested that there may be water ice in some deep craters near the Moon's south pole which are permanently shaded. This has now been reinforced by data from Lunar Prospector. There is apparently ice at the north pole as well. A final determination will probably come
One of a number of disks used by NASA to promote public understanding of the Moon.Samples of moon rocks and moon soil are embedded in a clear plastic disk for convenient viewing.
The Earth and Moon as seen by the NEAR spacecraft, as it passed beneath their South poles (note Antarctica, at center Earth image) in January of 1998. As dark as the Moon appears in comparison to the Earth, it is actually five times darker yet, as its brightness was enhanced by that much in creating this picture. (NEAR Spacecraft Team, JHUAPL, NASA, apod980129)
The Moon's distance from the Earth changes by 6% from its average distance as it moves toward perigee, or apogee. As a result, the apparent size increases or decreases by 6%, as well. These images show the apparent size of the Moon at apogee (on the left), and at perigee (on the right). (The change in size is not so obvious when the time between the extremes is two weeks, as when images are placed side by side.) When
Modern Definition:
A Blue Moon is commonly the name given to the second full moon in a month. Since a full moon occurs every 29 1/2 days, if there is a full moon on the 1st or 2nd day of a month, there is a good chance there will be a second full or blue moon that month.
In 1999, there were two blue moons very close together. One on January 31st (after the full moon on Jan. 2nd) and the other on March 31st (after the full moon on March 2nd).
There was another in November 2001, but not again until July 2004.
Tuesday, March 4, 2008
welcome
Hellow every boby in my blog . I feel interesting when some body visit my blogger. In my blogger i provied it many information and picture.
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