How phase of moon changes?

Dear Readers,
This article includes the basic facts about moon, our natural satellite.
It will fulfill your basic question.,
how phases of moon changes?
Hope you'll enjoy reading.

The Moon is the only natural satellite of the Earth, and the fifth largest satellite in the Solar System. It is the largest natural satellite of a planet in the Solar System relative to the size of its primary, having a quarter the diameter of Earth and ¹⁄₈₁ its mass.

The Moon completes its orbit around the Earth in approximately 27.3 days (a sidereal month). The Earth and Moon orbit about their barycentre (common centre of mass), which lies about 4700 km from Earth's centre (about three quarters of the Earth's radius). On average, the Moon is at a distance of about 385000 km from the centre of the Earth, which corresponds to about 60 Earth radii. With a mean orbital velocity of 1,023 m/s, the Moon moves relative to the stars each hour by an amount roughly equal to its angular diameter, or by about 0.5°. The Moon differs from most satellites of other planets in that its orbit is close to the plane of the ecliptic, and not to the Earth's equatorial plane. The lunar orbit plane is inclined to the ecliptic by about 5.1°, whereas the Moon's spin axis is inclined by only 1.5°.

Lunar Phases

The Moon appears to go through a complete set of phases as viewed from the Earth because of its motion around the Earth, as illustrated in the following figure.

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In this figure, the various positions of the Moon on its orbit are shown (the motion of the Moon on its orbit is assumed to be counter-clockwise). The outer set of figures shows the corresponding phase as viewed from Earth, and the common names for the phases.

Take a look at these video clips below, that might be help you to visualize what happen actually while phase change at the outer space. The first clip shows what the Sun, Earth, and Moon might be doing, as viewed from outer space. The  2nd clip shows you what you would see if you were looking up from your place.

I hope this information might helpful to you to understand how phase change actual occurs.

Now keep in mind this information while you see the moon in the deep dark night sky.

What Is a Lunar Eclipse and HOW it works?

So what is a lunar eclipse? 
These eclipses are actually remarkably simple considering how interesting and dynamic they can be. Basically, the Earth's shadow blocks most of the sunlight from directly illuminating all -- or a portion -- of the moon's surface.

Digital composites like this one are becoming popular
ways to capture the progression of phenomena like lunar eclipses

The moon has been Earth's trusty sidekick for billions of years. And as it endlessly cruises around our planet, once in a while this scrappy satellite precisely aligns within Earth's shadow, taking on an eerie, reddish glow. And what's this phenomenon known as? A lunar eclipse, of course.   

Earth generates two cone-shaped shadows: The umbra is the dark, center shadow, and the outer, more diffused one is known as thepenumbra. The penumbra encases the umbra. Both these cones are cast out from behind the sunlit side of the planet. Consequently, lunar eclipses only occur during the full moon phase(when the moon and the sun are on opposite sides of the Earth). Solar eclipses are possible only during the new moon phase (when the moon plays "monkey in the middle" between the sun and Earth).

Inside this Article

1. Introduction to How Lunar Eclipses Work
2. What Is a Lunar Eclipse?
3. Classifying Lunar Eclipse
4. To know more ..click here

3 Common Reasons which reveals that EARTH is SPHERE...

If you didn't know that the Earth is a sphere, there are three common observations you could use to convince yourself that it is.

• The first common observation is the shape of the moon. First, the face of the full moon is circular, and that would lead you to believe that it is a sphere rather than a disc. When the moon eclipses the sun, the shape of the shadow is always circular, which clinches a spherical shape for the moon. By extrapolation, you could assume that the Earth is a sphere also.

• Also notice that when the moon is being eclipsed by the Earth (a lunar eclipse), the part of the moon that is eclipsed is actually the shadow of the Earth. This shadow tells you that the Earth is a sphere just like the moon.
• A third way to see that the Earth is a sphere is to look at how objects in the distance "disappear" as you get farther away. For example, a 100-foot-tall ship that is 15 miles away is not visible. That's because it is blocked by the curvature of the Earth. As it approaches, it "rises." First the tip of the mast is visible, then more and more of the ship comes into view as the ship gets closer.

How Gear Ratios Work..?

You see gears in just about everything that has spinning parts. For example, car engines and transmissions contain lots of gears. If you ever open up a VCR and look inside, you will see it is full of gears. Wind-up, grandfather and pendulum clocks contain plenty of gears, especially if they have bells or chimes. You probably have a power meter on the side of your house, and if it has a see-through cover, you can see that it contains 10 or 15 gears. Gears are everywhere where there are engines and motors producing rotational motion. 
From this article you will learn about gears, gear ratios and gear trains so that you can understand what all the different gears you see are doing.

Gears are generally used for one of four different reasons:

1. To reverse the direction of rotation
2. To increase or decrease the speed of rotation
3. To move rotational motion to a different axis
4. To keep the rotation of two axis synchronized

Inside this Article

1. Introduction to How Gears Work
2. Understanding the concept of the gear ratio
3. Gear Trains
4. Other Uses for Gears 
5. To know more...click here

How X-rays Work?

X-rays are basically the same thing as visible light rays. Both are wavelike forms of electromagnetic energy carried by particles called photons. The difference between X-rays and visible light rays is the energy level of the individual photons. This is also expressed as the wavelength of the rays.

X-ray technology has allowed us to see
 inside the human body since 1895. 

Our eyes are sensitive to the particular wavelength of visible light, but not to the shorter wavelength of higher energy X-ray waves or the longer wavelength of the lower energy radio waves.

Discovery of X-RAY: 

As with many of mankind's monumental discoveries, X-ray technology was invented completely by accident. In 1895, a German physicist named Wilhelm Roentgen made the discovery while experimenting with electron beams in a gas discharge tube. Roentgen noticed that a fluorescent screen in his lab started to glow when the electron beam was turned on. This response in itself wasn't so surprising -- fluorescent material normally glows in reaction to electromagnetic radiation -- but Roentgen's tube was surrounded by heavy black cardboard. Roentgen assumed this would have blocked most of the radiation.

Roentgen placed various objects between the tube and the screen, and the screen still glowed. Finally, he put his hand in front of the tube, and saw the silhouette of his bones projected onto the fluorescent screen. Immediately after discovering X-rays themselves, he had discovered their most beneficial application. 

Inside this Article

1. Introduction to How X-Rays Work
2. What's an X-Ray?
3. The X-Ray Machine
4. Are X-Rays Bad For You? 

How Reverse Osmosis (RO system) Works?

Now-a days we all are using/planting  RO- system to prevent our health from drinking water related deceases/infection.

Don't feel stupid if you've ever seen a news story about a terrible drought/save water its limited resource., then turned to your computer to see your pretty ocean beach screensaver and thought, "Why don't they just use that?"

Of course, within a moment, you probably made a few points to yourself. One, the sea is salty. Two, salty water isn't so great for drinking or growing plants. Three, you can't just take the salt out of water, just like you couldn't dissolve the sugar out of your tea. Or can you?

Can't quite visualize osmosis in action?
 Here's a handy illustration to help. 

Desalination plants use reverse
osmosis to turn salty water into fresh. 

Basically Reverse osmosis is one of the processes that makes desalination (or removing salt from seawater) possible. Beyond that, reverse osmosis is used for recycling, waste-water treatment, and can even produce energy.

Inside this Article

1. Introduction to How Reverse Osmosis Works
2. What's Osmosis, Anyway?
3. Osmosis Down, Flip it and Reverse it

4. Where is Reverse Osmosis Used?
5. Smaller-scale Applications of Reverse Osmosis
6. Disadvantages of Reverse Osmosis
7. To know more..click here..

How Hangovers Work...??

It is always been question in our mind that "why people behave like mad or doing activities like a small child while they drunk..?"
This article will give you answer of your questions about HANGOVER along with causes which may increase the chances of HANGOVER.

More than 75 percent of alcohol consumers have
experienced a hangover at least once.  

Inside this Article

1. Introduction to How Hangovers Work
2. What is a Hangover?
3. Biology of a Hangover: Vasopressin Inhibition 

Difference Between CD, DVD and Blu-ray discs...

Blu-ray has finally won the high definition format war, but that is just the beginning. There is a lot of confusion out there among the general public about the difference between DVD and Blu-ray discs. Although Blu-ray discs look exactly the same as DVDs in size and shape there are many differences between the media, including storage capacity, laser technology, disc construction, image resolution and player compatibility.

Storage Capacity

Storage capacity is measured in gigabytes (GB), like computers and iPods. The more GB the disc has more information it can hold.

·         DVD- Single layer DVDs can store about 4.7 GB of data, which is about two hours worth of movie. These are commonly referred to as DVD-5s. Double layer DVDs, or DVD-9s, can store twice the amount of data at 8.7 GB. This equals about four hours of movie, or one “Lord of the Rings” movie.

• Blu-ray- Single layer Blu-ray discs store approximately 25 GB of data, this equals about two hours of high definition information or 13 hours of standard definition information. Double layer Blu-ray discs can hold about 50 GB equaling about four and a half hours of high definition information or 26 hours in standard definition. Potentially you could put all three “Lord of the Rings” movies on one double layer Blu-ray disc.

Laser Technology
Lasers are used in both media to read the information stored on the disc. As the disc spins the laser reads the information and transfers both picture and sound to the television.

• DVD- DVD players use a red laser at 650nm wave length to read DVD discs. As the disc spins the laser reads the information encoded on the media and produces an image and sound on your television.
• Blu-ray- Like the name suggests Blu-ray players use a blue laser to read the stored information. Blue laser wavelengths are shorter than the red at 405nm and are about two and a half times smaller in diameter than red lasers. This allows for closer and more precise reading of information stored on the disc.

Disc Construction
Physically, Blu-ray and DVD discs are identical. Both media have grooves or pits on their bottom layer than enables the laser to penetrate through and read the stored information.

• DVD- Since DVDs are read with a red laser the grooves on its underside need to be wide enough to accommodate the larger wavelength. Because the grooves are so far apart only 4.7 GB of information can be stored on each layer of the disc. DVDs also include a protective layer designed to resist scratching.
• Blu-ray- The grooves on a Blu-ray disc are much thinner and closer together because the blue laser used to read the disc has a shorter wave length and is two and a half times thinner than the red laser. This allows the Blu-ray disc to squeeze almost five times as many grooves on to a disc exactly the same size as a DVD. Blu-ray also includes a protective layer to prevent scratches. This protective layer is physically thinner than the one on a DVD, but it has a hard coating that makes it more scratch resistant.

Image Resolution
Image resolution is measured by the number of vertical lines times the number of horizontal lines of light in a picture. It is represented by the number of horizontal lines going across the screen like 480, 720 or 1080. The higher the number the higher the resolution and more detailed the picture.

• DVD- Almost all DVDs have a standard definition resolution of 480 or enhanced definition resolution of 520. These resolutions look great on a standard “tube” TV utilizing all available pixels on the screen. However, if blown up to accommodate a widescreen HDTV the picture may look grainy. Although a DVD can store high definition data it would only fit about 30 minutes maximum.
• Blu-ray- Blu-ray was designed for high definition 1080 display. Since they can store 25 GB of data you can fit an entire HD movie on a single layer disc. Blu-ray currently has the best image resolution on the market and looks great on HDTVs. Blu-ray discs are one of the few signal sources that displays in 1080, not even HD cable or satellite companies can claim that yet.

Player Compatibility
Some of us are still recovering from the VHS to DVD format switch of almost 10 years ago, slowly upgrading our VHS collections to DVD. Now, there is a new, better format on the horizon and many are still skeptical. However, you’ll be happy to hear that all Blu-ray players support DVDs.

• DVD Players- Blu-ray discs cannot and will not play in a standard DVD player, because the red laser used in DVD players is too large to read the tiny grooves in a Blu-ray disc.
• Blu-ray Players- All Blu-ray players currently on the market (including the Playstation 3) are backwards compatible and will still play standard DVDs. However, the DVD image displayed, while still decent, will not be high definition quality like a Blu-ray disc.

Fear not technophobes, the transition from DVD to Blu-ray will be relatively painless once the price of Blu-ray players starts to come down. With the exception of storage capacity perhaps the best thing Blu-ray has going for it is its higher image resolution and compatibility with standard DVDs. To find the Blu-ray player that fits your budget see our Blu-ray DVD players review.

How Hubble Space Telescope Works...!!!

This article has been posted for the all curious science( Astrology) lovers.
we all know the use of telescope..In simple words, It helps us to see enlarge version of the object which appeared tiny by naked eye.
Hubble space telescope does the same job but in interstellar space.
Its working is too different than what we are thinking a typical telescope does.
It will be good for you to understand it by following the links bellow..

Preflight inspection of the Hubble Space
Telescope's primary mirror.

The Hubble Space Telescope
is deployed from the cargo bay of the space shuttle.

If Hubble couldn't focus,
it wouldn't have been able to take this image
of a dying star named NGC 6369 on Nov. 7, 2002.

The Hubble Space Telescope in orbit

Inside this Article...

1. Introduction to How Hubble Space Telescope Works
2. COSTAR Saves the Day.
3. Anatomy of the HST

4. Hubble's Scientific Instruments: WFPC2, NICMOS and STIS
5. Hubble's Scientific Instruments: ACS and FGS
6. Hubble's Spacecraft Systems: Generating Power and Talking to Ground Control
To know more..click here...

How fast should my Internet connection be to watch streaming HD movies?

Here I am posting first article..about.."How fast should my Internet connection be to watch streaming HD movies?"
We all faces the problem of internet speed when we are trying to watch online videos.
This article will lead to the answers of all your questions like..
" why your browser takes too much for streaming?
" what kind of internet connection do you need?
etc..etc.
Inside this article..

1. How fast should my Internet connection be to watch streaming HD movies?
2. Internet Speed and Bandwidth for HD Video Quality

To know more...click here