Hi guys, again we are here and in this opportunity I want to share 6 curiosities about the space, I am still writing educational and informative content that I hope will be useful ... Let's start!
1. How far is the sky?
We have the illusion that above us there is a kind of vault that is blue during the day and black during the night and we call it "firmament" or "sky". Well, what we really have is a layer of air that surrounds us and covers us called atmosphere.
If the question is, where does the space begin? This one is surprisingly close: 100 kilometers up. It is the highest that an airplane can fly, because beyond that the air is so thin that it can not sustain the wings. This border is called "Karmán line". Even so, even at a height of 10 thousand kilometers you can still find gas molecules. This layer is called Exosphere.
2. Why do the planets revolve around the sun?
The force of gravity of the Sun pulls the planets towards it, but at the same time, the lateral force that the planets carry from their origin pushes them in another direction. The result is that almost circular or elliptical orbit. This is a result of the way in which the solar system was formed.
4500 million years ago a huge molecular cloud that slowly turned began to collapse by gravity and this collapse amplified the rotation by the conservation of angular momentum. This formed a disk, which is the form of greatest balance between gravity and centrifugal force caused by the disk. In the center of the disk was the amount of mass and gravity, that the atoms made fusion. Thus the sun was born and in other parts of the disk, other spirals formed the
planets and their natural satellites.
3. Why are there eclipses?
Surely you know that the moon revolves around the earth and the earth around the sun. When the earth is between the sun and the moon, it casts its shadow over it and the moon darkens or becomes reddish. It is a lunar eclipse.
When the moon comes between the sun and the earth, it casts its shadow over us and creates a solar eclipse, which can be partial, total or null. Eclipses may look different, or not be seen, depending on where you are in the world.
If you want to be aware of what you can see, get in touch with the astronomical organization in your area.
If you want to know a little more about eclipses visit my previous post. Here
4. How many stars are there in the universe?
Nobody knows exactly. We know approximately the star number in the Milky Way, our galaxy: 100 billion. We multiply that by the number of galaxies that we calculate in the visible universe and it gives us 70 Quintillions of stars (a 7 with 34 zeros). But the universe probably extends much, much further.
5. What happens if two metals touch each other in space?
If two pieces of the same metal come together in space, something very curious happens: they are welded. This phenomenon is called "cold welding" and occurs because, because there is no air or other substances between one piece and another, they do not know that they are two different objects and simply join.
6. What does "Astronaut" mean?
It is a modern word coined from the Greek terms "Astron", which means star, and "Nautes", sailor or traveler. It was translated as "Navigator of the stars". If you want to be a "star traveler", you must combine physical and intellectual fitness: have excellent health and a degree in science.
If you are interested, get more information at:
Nasa.
https://nasajobs.nasa.gov/
European Space Agency
http://www.esa.int/
Although it is not impossible, they are very competitive places: the number of people who have left our planet to date is only 593.
We have reached the end of this little reading, I hope you have been to your liking and that you have learned something new about space.
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Take a look at my blog. See you in the next post ...
References
- http://astronimate.com/article/how-did-the-solar-system-form/
- https://phys.org/news/2017-02-flirtatious-lunar-eclipse-friday-night.html
- https://www.universetoday.com/25410/how-far-is-space/
- https://www.space.com/26078-how-many-stars-are-there.html
- http://www.esa.int/Our_Activities/Space_Science/Herschel/How_many_stars_are_there_in_the_Universe