Stars are perhaps the most captivating objects in the sky. No child could have sung “Twinkle, twinkle, little star” and not wonder what they are. While much has already been written about stars, man continues to explore to better understand these astronomical objects scattered around our vast, mysterious universe. Here are the ten most interesting facts about stars you may have never heard before.
1. There could be over a Septillion stars in the universe
Some people say that there are more stars than there are grains of sand on the face of the earth. But no one would try to count them individually for the universe is so vast. For instance, the Milky Way galaxy, where our solar system belongs, is said to have 100 billion stars.
This is just one galaxy. Scientists estimate that there are likely to be over 100 billion to 1 trillion galaxies in the universe. If you multiply that, you would have 10 sextillion to 1 septillion stars!
2. No, the stars do not twinkle.To your inner child’s dismay, stars do not twinkle. They may look like they are twinkling because of the turbulent state of our atmosphere. It is quite hazy in our horizon that makes stars look like they are blinking. As the light from a star shines through the Earth’s atmosphere, it passes through layers that have different densities. Hence, a star appears as though it changes in color and brightness or, in other words, twinkles.
3. The sun, the closest star to Earth, is moving.
You may have heard from your grade school teacher that the sun is a stationary object which the Earth and other planets in the solar system revolve around. Well, that may be true in relation to earth and a fair approximation of the relationships between the sun and the planets.
But the truth is, the sun including the entire solar system is moving. It revolves around the Milky Way but at a very slow rate of 828,000 kilometers per hour. In fact, it would take around 230 million years for it to complete its orbit around the galaxy!
4. It would take you roughly 35,000 years to reach the nearest star next to the Sun.
The star known as Proxima Centauri is the nearest star next to the Sun and it is about 4.2 light years or 40,000,000,000,000 kilometers away from Earth. In other words, if that star casts a light upon Earth, the light will travel for 4.2 years before it reaches us.
To have a greater sense of how far this is, imagine the Earth an inch away from the Sun and Proxima Centauri would be at a far distance of 4.2 miles! If you ride a spacecraft with the speed of Voyager 2, it should take you 35,000 years before you get there!
5. The Sun produces the energy equivalent to 100 billion typical hydrogen bombs every second!It converts 4 million metric tons of hydrogen every second into energy. If only this energy can be harnessed, it would sustain the needs of mankind for 500,000 years, and that is just for one second. If you take the largest known star VY Canis Majoris which is roughly 2,000 times the size of the Sun, its energy output would be unimaginable.
6. One day, the sun will die.All things must come to an end, that includes the Sun. The Sun is said to be a middle-aged star that was formed out of a solar nebula about 5 billion years ago and it will die in about 6 billion years. Scientists have studied the life of stars including that of the Sun. They believe that 3.5 billion years from today, the Sun will shine 40 percent brighter than it does at present. The heat will be so high, it will make oceans boil and the resulting water vapor will be lost forever to space.
In this phase, Earth will become like that of Venus – hot and dry, and life will no longer be possible on the surface of the Earth. The core of the Sun will run out of hydrogen and will become unstable until it expands and blasts. But the Sun’s death is estimated to be complete in a trillion years’ period.
7. All you need are clouds of dust with great turbulence within to create a star.Stars are born out of dust clouds that are scattered throughout space. The turbulence or instability deep within these dust clouds give rise to knots which eventually develop mass allowing gas and dust to collapse. While the cloud collapses, the object at the center starts to heat up. This hot core amidst the clouds will eventually become a star one day.
8. You would need 1,100 years to circle the largest known star in the universe.
The largest star in the universe is the VY Canis Majoris. It is 2,800,000,000 kilometers in diameter. It would take you 1,100 years to complete an orbit around it if you are aboard a passenger airplane that flies at 900 kilometers per hour. Scientists estimate that this star is around 1,800 to 2,000 times the size of the Sun.
9. The larger the star, the shorter the life span.If you think larger stars are more invincible than smaller ones, you’re mistaken. More massive stars may have larger amounts of hydrogen to fuel its nuclear reactions than smaller ones, but they have shorter lives because they use up their energy at a much faster rate than the smaller stars.
10. If you look at the stars, you are actually looking back in time.This is because light from stars and galaxies in far away distances take a long time, about thousands or even millions of years, before it can reach the Earth. The largest star is said to be 4,900 light years away from the earth. If you are looking at it now, you are actually seeing how it was 4,900 years ago! Cool!