Results tagged “science” from PlanetGreen.org

Stars Once More: The Story Of Neutron Stars

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Magnetar Mysteries

Recently, a relatively close (16,000 light-years away) magnetar called CXO-JI64710.2-455216 with 40 solar masses, has been discovered. Normally, such a star would be a black hole, according to the commonly accepted black hole model.

But not according to my new temporary-stage model. Over millions of years, a black hole will collect hundreds of tons of matter in its singularity. Finally, just as in a normal, main-sequence star, it will begin to collapse upon itself. It cannot contract anymore, however, having already an infinite density, so the pressure will cause it to implode. Then, it will become a neutron star. This decodes the life cycle of neutron stars: stars that were once black holes. However, some black holes will maintain their stability, and they are called permanent-stage black holes. 


BANG!

Black-Hole-Planetgreen.jpg

The story of the universe starts with black holes and burned-out white dwarfs. Not a star exists that is still shining, and no new stars are created. Slowly these dark galaxies are spiraling inward towards their central black holes, over a process of millions of years. 


Finally, all of the extinguished white and brown dwarfs are concentrated into the singularities. Then, the black holes start merging. This last stage of this old universe is causing it to contract. Then, after billions of years, the black holes are concentrated into one singularity: a cosmic calamity. But the black hole's center is a temporary-stage singularity.


So then it explodes in a "meganova": the Big Bang has begun. Within microseconds of the explosion, the matter and antimatter levels are determined, the critical mass value has been deter-mined, and the beginning (and the end) of the entire macrocosm has been decided. The universe as we know it has been created.


Why Are Clouds White?

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clouds2.jpgWhen you look at the sky on most days, you'll see a few clouds slowly drifting past, pushed by the wind. You might see the shape of a camel in one and a flower in another. You probably already know why clouds exist: water evaporates in the sunlight and rises into the sky, where it again forms tiny water droplets. When the droplets are too large to stay in the air, they fall to the ground as rain and the cycle begins again. But did you ever wonder why clouds are white, and why they become gray during a storm?

Katrianna wrote about why the sky is blue in a previous article, which explained how light is made up of many different colors. White light is a combination of all of the colors. Clouds are white because the water droplets or ice crystals (at a certain altitude, the water freezes to become ice) reflect all of the colors of light in a process called Mie scattering. (All of the colors are reflected in the same way, so they combine to become white light.)

Clouds are dark when they are so thick that the sunlight is blocked by the moisture. When you look down on dark clouds through an airplane window, the clouds will always look bright white. This is because the water or ice on the surface of the cloud is still reflecting the light. Thus, every cloud will have a silver lining -- if you view it from an airplane!

Club-Winged Manakins Sing By Vibrating Feathers

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It’s not a new idea that crickets chirp by rubbing together their toothed wings, but new studies suggest that birds also vibrate their wings to attract mates. Although an animal singing by rubbing together parts of its body is a practice common among arachnids and insects, only one vertebrate is known to “sing,” or even to make noise, in that manner.



Male club-winged manakins, found in the rainforests of Ecuador, make a series of high-pitched notes, so fast that the individual tones are indistinguishable, every time they flap their wings. Other birds’ flapping may sound like clapping or wind, but this songbird’s sound is unique. To the manakins, which are territorial, the noise is used to attract female birds and to tell other male birds to leave their region.

Manakins flap their wings over 100 times a second, or twice the speed of a hummingbird. On one wing, one feather had seven bumps and on the other wing one feather was stiff and curved, serving as a bow for the bird’s ridged feather. Every time the bird flaps its wings, the stiff feather vibrates against the ridges, producing the unusual sound. The surrounding feathers, which also quiver when the feathers are struck, strengthen the noise.

To find out more about this unusual animal behavior:
Tuning-fork feathers give bird its ‘singing’ wings
Bird “Sings” Through Feathers

Why Leaves Change Color in Fall

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Trees and bushes colored bright shades of orange, yellow, red, and brown are a familiar sight in fall. They light up the hillsides for a few months, until the leaves fall from the trees. But why does this happen?

When maple trees' leaves are green, they are absorbing sunlight and carbon dioxide. The chlorophyll in the leaves enables them to turn those two ingredients into glucose, a kind of sugar which gives them energy and helps them grow, using a process called photosynthesis. When the photosynthesis stops, the glucose is trapped in the leaf. Sunlight and cold weather turn the glucose red. Oaks turn brown because of the wastes left in their leaves, but the brown leaves don't actually drop from the tree. Instead, they stay on the branches until late winter or early spring, when the new leaves replace the old ones. Other pigments found in leaves called carotenoids are yellow-colored, which is why aspen and larches turn golden. You can't see the colored pigments in summer because the chlorophyll's green coloring is stronger than the others. It is only when the chlorophyll fades out of the leaf that the others are visible.

Later on, in late fall or winter, the deciduous trees lose their leaves because, although their trunk and branches will not freeze, the leaves cannot endure such frigid temperatures. Also, because winter has less sunlight than the other seasons, the leaves cannot make very much energy. It is more efficient for the tree to live off of the energy it stored, just as many hibernating animals live off of the food they ate in the warmer seasons.

Evergreen trees have their own system of coping with winter so that their needles don't freeze. They have a waxy coating on the needles and their cells have fluids that prevent freezing inside them. So while the deciduous trees aren't producing any oxygen, the evergreens take over. This is yet another reason why it's important to conserve these valuable resources.

This is how trees produce the colors commonly termed "fall color" before shedding the leaves, a beautiful annual phenomenon.

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