THE MOON:the only natural satellite of earth

THE MOON:the only natural satellite of earth  

 The moon has been known since ancient times, but many people still have no idea that this celestial body is not just a heavenly body. A lot of people often ask- “What’s the difference between Earth and Moon?” Well, there are some differences between them. On one hand, we can say that the moon is smaller than the Earth. Also, the moon consists of less elements compared to the Earth. Besides these facts, the major difference between these two bodies is their distance from each other. As per NASA, our moon is about 239,000 miles away from us. In comparison,  Earth is around 93 million miles away from the moon. This huge distance makes the moon appear like a tiny dot in the night sky. So, if you want to know what’s the difference, then here are some interesting facts-

 • Both Earth and Moon were formed at the same time!

 • The average distance of Earth to the Sun is 149 million miles. This value is different for the moon. Its distance is 239,000 miles away.

 • There are seven other moons orbiting Earth, including Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune.

 • If the Earth was a solid ball, then the Moon would cover its surface only 1/48th of its size.

 • When it comes to mass, the Moon is much lighter than the Earth. As per Science Daily, the moon weighs only 1/327th of the entire planet.

Moon has no atmosphere

 The moon has been a subject of many theories and studies since the ancient times. One of them is that the moon is the only natural satellite of Earth. The moon does not have any atmosphere; hence, its surface gravity is less than earth's surface gravity. That means, if we take the weight of the earth along with the moon, then that would add up to 2.1 * 10^24 kg. Therefore, we can conclude from this theory that the moon is indeed a natural satellite of earth. Moreover, this theory explains the reason for the tides on the earth. If the moon were not a natural satellite of earth, then the water would not get affected by lunar gravitational pull. But due to the fact that the moon affects the earth, a high tide occurs on the surface level of oceans.

 Moon orbits close to the earth

 Another theory about the moon revolves around the fact that it goes close to the earth and is orbiting around it. This theory suggests that the moon appears smaller to us because it is closer to our planet. In other words, it is a bigger object but appears small because it is so close to the earth. Another point to consider about this theory is that the moon is moving away from the axis of rotation of the earth. So, what this theory means is that the moon is in motion and rotating around the earth at a speed of 1.5° per hour.

 Moon is the closest celestial body to Earth

 This theory is based on the observation of astronomers who say that the moon is the closest celestial body (next to the sun) to the earth. We know that the moon is roughly 238 thousand kilometres away from the earth. Because the distance between them is so long, it is difficult for us to observe anything on the moon. However, when we look at the moon through telescopes, we are able to view some details like craters, mountains, and so on.

The moon has been a constant companion to Earth since its formation 4.5 billion years ago, but did humans ever wonder what life was like outside our own solar system? Well, now we can explore that question thanks to NASA’s Lunar Reconnaissance Orbiter (LRO) mission. This spacecraft, which launched in 2009, has been orbiting the moon for over five years. During this time, LRO has taken millions of images of the lunar surface, giving scientists an entirely new perspective of the planet and a chance to study the environment around the moon.

 While the moon may seem barren at first glance, there are plenty of resources on its surface that might surprise us. Scientists have discovered water ice just below the surface, where they were able to collect samples using a robotic arm attached to the orbiter. They also believe there is enough hydrogen fuel underground to power space stations for thousands of years.

 LRO has also helped scientists learn about the moon’s geology, and how it compares to Earth's geological layers. In fact, some scientists argue LRO should be renamed the “Earth-observing orbiter.” Using data from the craft, studies show that the moon formed out of material left over from the collision between Earth and a Mars-sized object called Theia. The research suggests the moon could hold clues as to why Earth's core heats up at certain times, even though it rotates much faster than the rest of the planet.

 This mission isn't stopping anytime soon -- NASA plans to continue to use LRO until 2020. But don't worry, if astronauts want to visit the moon again, they'll have the help of LRO. The craft can still operate independently, although it won't be collecting any new information. Instead, it will provide commands to other vehicles traveling to the moon.

 NASA says it hopes to make LRO's discoveries public knowledge, as well as share them with students through educational programs. If you're interested in learning more about the moon, you can watch these videos of LRO here.

 lunar moon space planet nature sky orbiting earth planets nasa moonshots mars astronaut spacecraft education videos science.

This is how moon eclipse looks like- 

The moon is the only natural satellite of Earth, orbiting around it at an average distance of 238,000 miles (384,000 kilometers) away from our planet. Its mass is about ⅓ that of Earth’s. The Moon is similar to other terrestrial planets, having rocky surface and inner core, mantle, and outer core. It has no atmosphere but instead its gravity is due to electromagnetic forces generated by its iron-rich core. As compared to other worlds, Earth is unique due to the size of its core, which contains the majority of its metals, including nickel, iron, and magnesium. These materials are the reason behind Earth's magnetic field and they also determine the rotation rate of Earth. Because Earth has no significant atmosphere, the Moon receives only solar radiation; however, it still retains enough heat from radioactive decay of its interior to keep molten rock hot enough to sustain plate tectonic activity.

Why moon have dark spots ?

The Moon has dark spots because the sun is not always out. This is due to the fact that the Earth's shadow moves across the Moon. In addition, the Earth rotates around its own axis, giving us seasons. These two factors cause the Sun to move below the horizon at different times during the day. The Moon does not rotate around the Earth like we do - this causes the Moon to stay above the horizon at night.

The craters on moon - 

●Aristarchus crater

         Credits - NASA GALLERY

●Moore F crater

         Credits - NASA GALLERY

The Moon has no atmosphere and its surface temperature never exceeds -180 degrees Celsius. Therefore, it's not surprising that we can observe shadows of mountains and craters and other features due to sunlight reflection from the Moon's surface.

 In order to understand how these shadows are formed, let's take a look at the lunar lander that landed on the Moon back in 1969. When the Lunar Rover was deployed onto the surface of the Moon, it created a shadow behind itself that looked something like this:

 As you can see, the shadow looks like a cone with the apex pointing down (because of light being refracted downwards). This happens because the Sun shines through the Earth and reflects off the surface of the Moon. As the rays of sunlight hit the ground, they are bent slightly towards the horizon and then refract upwards through the air. Because the Moon has no atmosphere, this bending effect is exaggerated. In fact, if you were standing on the surface and looked straight up into space, your eyes would see only a ring of light around the sky. If you were looking directly north, you would see a bright disk of light on the horizon. That bright disk of light is actually the sun shining through our atmosphere and illuminating the surface of the Moon before reflecting right back at us.

 This phenomenon is called Rayleigh scattering and explains why the shadows of mountains and crags cast on the surface of the Moon appear darker than their surroundings. The same thing happens here on Earth, but it is much less noticeable since we have a lot more atmosphere between us and the Sun.

Water on moon - read the article

         Credits - NASA GALLERY