Author Archives: dempsy

Gravitational Singularity

Posted on April 30, 2018 by dempsy

Gravitational Singularity, or spacetime singularity, is a point with infinitely small size and infinitely big density, gravitational force and time curvature. At that point, no physicals laws we know right now can be applied. According to the big bang theory, our universe is expanded from a universe singularity. According to current theory, when an object … Continue reading Gravitational Singularity → Continue reading →

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The Dark Forest Theory

Posted on April 30, 2018 by dempsy

If you are interested in aliens and Fermi paradox, there is a must-read novel “The three-body problem”. The novel was written by a Chinese writer Liu Cixin, and in the novel Liu introduced a theory called “The Dark Forest Theory”. The theory has two axioms. The first one is that “survival” is the first need … Continue reading The Dark Forest Theory → Continue reading →

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What will black hole be eventually?

Posted on April 9, 2018 by dempsy

Among all the astro bodies, black hole is unique. We all know that black holes have strong gravitation effect that nothing, even including light, is able to escape from black hole. Then, a question arises and attracts me a lot – What will black hole be eventually after it absorbs a lot of matters? Will … Continue reading What will black hole be eventually? → Continue reading →

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Halley’s Comet

Posted on April 9, 2018 by dempsy

Halley’s Comet is well-known to people and it might be the most famous comet in the world. However, people know it but most of people do not know what makes Comet Halley famous. In fact, Comet Halley is famous because it is the only short-period comet which regularly comes close to Earth and be visible … Continue reading Halley’s Comet → Continue reading →

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Fusion vs. Fission

Posted on March 17, 2018 by dempsy

The nuclear energy can be generated in two ways – fusion and fission. Both fusion and fission energy are generated by altering atoms. What is the difference between fusion and fission? And which way will generate more energy? As the word “fission” means separate a thing into different parts, nuclear fission means releases energy by … Continue reading Fusion vs. Fission → Continue reading →

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Moon and Tides – The Magic of Gravity

Posted on February 12, 2018 by dempsy

Our sea has a periodic rising and falling phenomena. At a time, the sea will go up and reach to the peak, and at another time, the sea will go down and leaves us an island or a beach. This phenomena is called tides. The tides are mainly caused by gravitational force from Moon. When … Continue reading Moon and Tides – The Magic of Gravity → Continue reading →

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Archeoastronomy – Armillary Sphere and Horolgoe in China

Posted on February 10, 2018 by dempsy

Through out the history of China, people are curious about how Sun, Moon and stars move according to Earth, and astronomers have created different tools to assist observing stars. Armillary Sphere The earliest well-known tool is Armillary Sphere (Chinese: 浑天仪), which is designed by Zhang Heng in 117 AD and completed in 125 AD. An … Continue reading Archeoastronomy – Armillary Sphere and Horolgoe in China → Continue reading →

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Historical Astronomers in Context – Nicholas Copernicus

Posted on February 4, 2018 by dempsy

Nicholas Copernicus Nicholas Copernicus was important to astronomy because his heliocentric theory. At that time, people believed that Earth is the center of the universe and all the other astro bodies were revolving around Earth. The appearance of the heliocentric theory from Nicholas Copernicus helped people correct their false assumption, which hugely helped scientists at … Continue reading Historical Astronomers in Context – Nicholas Copernicus → Continue reading →

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How Fast Light Travels

Posted on January 21, 2018 by dempsy

We all know light travels fast, but do you know how fast it can be? The answer 299,792 kilometers in a second. The fact is, if you can travel as fast as light, you could go around the Earth seven and a half times in just one second. Theoretically, there is nothing runs faster than … Continue reading How Fast Light Travels → Continue reading →

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First Post

Posted on January 14, 2018 by dempsy

This is the very first post. Below is a picture of my hometown. Continue reading →

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