Satellite captures double solar eclipse in action

Satellite captures double solar eclipse in action

 

A solar eclipse is pretty cool; a double solar eclipse is even better. On September 13, NASA’s Solar Dynamics Observatory (SDO) satellite caught an exceptionally rare sight: the Earth and the moon simultaneously passing across the face of the sun. (Watch an animation showing the momentary alignment of SDO, Earth, the moon and the sun.) Back on Earth, meanwhile, the hardy residents of Antarctica were treated to a partial solar eclipse.
Launched in 2010, SDO studies the sun’s churning atmosphere. Its tilted geosynchronous orbit gives the spacecraft a nearly uninterrupted view, but on rare occasions like this, the Earth or moon can get in the way.

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how many calories in a banana ..?

The banana is an edible fruit, botanically a berry, produced by several kinds of large herbaceous flowering plants in the genus Musa.

Nutrition Facts

Bananas

Amount Per 100 grams

Calories 89

% Daily Value*
Total Fat 0.3 g	0%
Saturated fat 0.1 g	0%
Polyunsaturated fat 0.1 g
Monounsaturated fat 0 g
Cholesterol 0 mg	0%
Sodium 1 mg	0%
Potassium 358 mg	10%
Total Carbohydrate 23 g	7%
Dietary fiber 2.6 g	10%
Sugar 12 g
Protein 1.1 g	2%

Vitamin A	1%	Vitamin C	14%
Calcium	0%	Iron	1%
Vitamin D	0%	Vitamin B-6	20%
Vitamin B-12	0%	Magnesium	6%

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We know the Earth is rotating, but why?

Why is everything in the Solar System spinning? And why is it mostly all spinning in the same direction?

 

Why is everything in the Solar System spinning? And why is it mostly all spinning in the same direction?

It can’t be a coincidence. Look down on the Earth from above, and you’d see that it’s turning in a counter-clockwise direction. Same with the Sun, Mars and most of the planets.  

4.54 billion years ago, our Solar System formed within a cloud of hydrogen not unlike the Orion Nebula, or the Eagle Nebula, with its awesome pillars of creation. Then, it took some kick, like from the shock wave from a nearby supernova, and this set a region of the cold gas falling inward through its mutual gravity. As it collapsed, the cloud began to spin.

But why?

It’s the conservation of angular momentum.

Think about the individual atoms in the cloud of hydrogen. Each particle has its own momentum as it drifts through the void. As these atoms glom onto one another with gravity, they need to average out their momentum. It might be possible to average out perfectly to zero, but it’s really really unlikely.

Which means, there will be some left over. Like a figure skater pulling in her arms to spin more rapidly, the collapsing proto-Solar System with its averaged out particle momentum began to spin faster and faster.

This is the conservation of angular momentum at work.

As the Solar System spun more rapidly, it flattened out into a disk with a bulge in the middle. We see this same structure throughout the Universe: the shape of galaxies, around rapidly spinning black holes, and we even see it in pizza restaurants.

The Sun formed from the bulge at the center of this disk, and the planets formed further out. They inherited their rotation from the overall movement of the Solar System itself. Over the course of a few hundred million years, all of the material in the Solar System gathered together into planets, asteroids, moons and comets. Then the powerful radiation and solar winds from the young Sun cleared out everything that was left over.

Without any unbalanced forces acting on them, the inertia of the Sun and the planets have kept them spinning for billions of years.

And they’ll continue to do so until they collide with some object, billions or even trillions of years in the future.

So are you still wondering, why does the Earth spin?

The Earth spins because it formed in the accretion disk of a cloud of hydrogen that collapsed down from mutual gravity and needed to conserve its angular momentum. It continues to spin because of inertia.

The reason it’s all the same direction is because they all formed together in the same Solar Nebula, billions of years ago.

 

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What's the difference between fission & fusion ?

What's the difference between fission & fusion ?

 

A nuclear reaction is a process in which atoms collide with other atoms and lose some of their original mass. Because of the principle of energy conservation the lost mass must reappear as generated energy, according to Einstein's equation E = mc². The two types of nuclear reactions used to produce energy are fission and fusion.

In a fission reaction, a heavy atomic nucleus is split into smaller nuclei, other particles and radiation. In a typical reaction, an atom of uranium 235 absorbs a neutron and splits into two lighter atoms, barium and krypton, emitting radiation and neutrons. Under special circumstances (the attainment of a "critical mass") the emitted neutrons can split further atoms, which in turn bring about more splitting, producing a very fast chain reaction. Nuclear power plants exploit the process of fission to create energy.  

In a fusion reaction, two or more light atomic nuclei fuse to form a single heavier nucleus. The mass change in the process is the source of nuclear energy. Fusion within the cores of the sun and other stars generates their radiating energy by fusing two hydrogen atoms to produce a helium atom. Current researchers are using magnetic vacuum chambers and laser beams in an attempt to generate the extreme high-temperatures necessary for the fusion process. If successful, the net energy gain would create a viable alternative energy option.

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Can you find the mistake

Answer:Actually the mistake is not in the numbers.The mistake is in the 1st line.

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Can You Answer This..??

Options:

A.18

B.24

C.16

D:None

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Test your knowledge | IQ level

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How Can We See Black Holes ?

How Can We See Black Holes?  

Can we see a Black holes..? if you have this question in your mind than here is answer for you.

 

Though we cannot "see" a black hole itself (since not even light can escape the hole's gravitational field), we may see the hole's effects on nearby matter. For example, if gas from a nearby star were sucked towards the black hole, the intense gravitation al energy would heat the gas to millions of degrees. The resulting X-ray emissions could point to the presence of the black hole.

Or, if a massive black hole were surrounded by large amounts of orbiting material -- gas, dust, even stars -- their rapid motion close to the hole could be observable via shifts in the energy of the radiation they emit. Evidence along these lines is mount ing, suggesting that black holes may not be that rare in the universe.

However, such evidence remains indirect and therefore inconclusive. To confirm that black holes actually exist, we'll need to be able to observe the gravitational waves they produce as they form or interact.

If scientists could build gravitational wave detectors of sufficient sensitivity, they should be able to measure the vibrations in spacetime generated by black holes as they form from a collapsing star, when they ingest large amoun ts of matter, or if they interact, even collide with a second black hole or another massive object, such as a neutron star. Certain patterns of gravitational waves emitted would reveal the "smoking gun."

So far, the wavelike disturbances in spacetime have eluded detection. In a relativistic universe, there should be no shortage of places in which to hunt for black holes. Much larger and more sensitive detectors are now under construction. With luck, soon gravitation scientists may be shouting "Eureka!"

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10 Mind-Blowing Facts About Black Holes

10 Mind-Blowing Facts About Black Holes

 

Here are 10 interesting facts about black holes

1. It was John Mitchell who actually first proposed the idea of ‘dark stars’ or object. Later, in 20th century the term ‘black hole’ was coined.

2. Black holes are actually leftovers of former stars and are so dense that nothing can flee from their dominant gravitational energy. 

3. If the formation of a black hole has taken place, it can continue to grow by absorbing additional matter.

4. Generally the life cycle of most of the stars end up being a white dwarf or a neutron star, but, black holes are considered to be the last evolutionary stage in the lifetime of a star.

5. There are mainly three types of black holes namely stellar, super massive and miniature black holes, depending on their mass.

6. Since black holes possess strong gravitational force which pulls all of the light into its center, they cannot be seen.

7. Black holes follow the laws of gravity and hence in order to affect the earth, the orbit of a black hole would have to be very close to the solar system, which is not likely.

8. Astronomers are confident that our own Milky Way galaxy has a super massive black hole at its center.

9.Black holes have to hold a massive amount of mass in an incredibly small space to have the required gravity to pull light in. For example, to make a black hole with the mass of Earth, the entire planet would need to be squeezed down to a space 9 millimeters across.

10.When anything (be it planets, suns, galaxies or particles of light) passes close to a black hole, they will be pulled in by its gravity. If something else acting on the object, like say a rocket, is stronger than the black hole's gravity, it can escape the pull.

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Why does water freeze from the top to the bottom..?

Why does water freeze from the top to the bottom..??

The answer lies in a very peculiar property of water.  As you guessed, the density of water of water increases as the temperature is lowered, but below 4^oC this trend is reversed.   Here is a graph from The Physics Factbook. It shows the density of liquid water vs. temperature. The reason it can show liquid water below 0°C is that water can be supercooled, not actually turning to ice for a long time.




So what happens is the water that is just slightly above the freezing point rises to the top so the freezing process starts there.   This is the same reason why ice is at the top of a lake in the winter and not at the bottom.  This is beneficial to ice skaters as well as fish and other aquatic fauna.

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