Tag Archives: Sun

The Sun is the star at the center of the Solar System. It is by far the largest object in the solar system. It contains more than 99.8% of the total mass of the Solar System (Jupiter contains most of the rest). Its diameter is about 109 times that of Earth (Equatorial radius: 695,700 km/432,288 mi, Equatorial circumference: 4.379×106 km/2,720,984.45 mi), and its mass is about 330,000 times that of Earth.

It is often said that the Sun is an “ordinary” star. That’s true in the sense that there are many others similar to it. But there are many more smaller stars than larger ones; the Sun is in the top 10% by mass. The median size of stars in our galaxy is probably less than half the mass of the Sun.

The Sun

About three quarters of the Sun’s mass consists of hydrogen; the rest is mostly helium, with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.

The Sun is a G-type main-sequence star (G2V) based on spectral class and is informally referred to as a yellow dwarf. It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense, that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.

The Sun is roughly middle-aged and has not changed dramatically for over four billion years, and will remain fairly stable for more than another five billion years. However, after hydrogen fusion in its core has stopped, the Sun will undergo severe changes and become a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury, Venus, and possibly Earth.

Planets and the sun - size comparison

Planets and the sun – size comparison

Sources

How Earth Could Die – 9 Horrible Ways

Now we’re living on a warm, hospitable planet. As Carl Sagan has said “That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.” We, humans, are the unquestionable rulers of our little oasis in a hostile universe. But all things must pass. The life on Earth, even the planet itself, won’t last forever. What’s more, the humans may go extinct before our planet (and probably before the life on it) dies out. Here some possible (and horrible) ways how planet Earth (or, at least, life on Earth) could die.

Continue reading How Earth Could Die – 9 Horrible Ways

8 Things that make Life on Earth Possible

Earth, our blue planet is an oasis in the vast, cold, and dark space. It is the only planet we know of that can support life. The fossil record tells us that life on Earth has lasted at least 3.5 billion years (the Earth is about 4.54 billion years old), with the oldest physical traces of life dating back 3.7 billion years. And, if some kind of disaster doesn’t intervene, our planet should continue to host life for at least another 1.75 billion years. Here are the 8 things that make life on Earth possible.

Continue reading 8 Things that make Life on Earth Possible

Timelapse of the future: an amazing video

Melodysheep published an amazing video titled “Timelapse of the future: a journey to the end of time”. This experience takes us on a journey to the end of time, trillions of trillions of years into the future, to discover what the fate of our planet, our sun, and our universe may ultimately be.

If this video won’t give you goosebumps, I don’t know what will.

Continue reading Timelapse of the future: an amazing video

Top 6 Biggest Stars in the Universe

What is the biggest star in the Universe? In fact, it is really hard to give an exact answer to this question since the universe is big, neighboring and the other galaxies are billions of light years away from us. But, we can give it a try. Here are the top 6 biggest stars in the Universe currently known by radius.

Continue reading Top 6 Biggest Stars in the Universe