Spacetime.

Spacetime, or space-time continuum, is a physical model. Space and time exist together.

Length, width, and height-these are what measure space. Millimeters, centimeters, meters, and etc. are units of measurement of space.

Past, present, and future are dimensions of time. Second, minute, hour, day, week, and etc. are units of time measurement.

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The stars.

In the sky there are many different stars.

Stars are celestial bodies that consist of gas and plasma. The sun is a star, too.

There are very different stars in space.

Constellations are made up of stars.

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Constellations.

Constellations are situated in the sky. These are group of stars. Constellations have different sizes. Also, the stars are arranged differently.

Some constellations were named after the characters of ancient myths and legends.

You can see many stars and constellations in the sky.

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https://www.shutterstock.com/image-vector/stars-moons-constellations-linear-design-astrology-2038932266

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Philosophy.

Philosophy (φιλοσοφία) is a study about knowledge and the mind. The word means "a love of wisdom" from Greek language.

Many different scientists of periods were interested in philosophy. Countries had unique views about world. Plato, Socrates, and Confucius were philosophers.

Also, philosophy created many other sciences, such as: sociology, ethics, aesthetics, psychology, and etc. People studied something with philosophical views.

This science can help make logical conclusions. Many religions have philosophical aspects.

Since ancient times people wanted to ask questions about life and the universe. Philosophical views have changed throughout history.

This science has influenced art and architecture in the countries. Philosophers wrote books, created paintings.

Students study philosophy during school lessons or in university.

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https://www.shutterstock.com/es/image-photo/universe-within-silhouette-man-space-brain-1211264470



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Astronomy.

Astronomy is a science about space. It studies different objects in the universe. Our Solar System, planets, stars, comets, satellites, and galazxies are studied by astronomy. Other sciences, such as: chemistry, physics, and mathematics are important for it.

Since ancient times people were interested in the sky and stars. Astronomy was studied in Ancient Greece, Egypt, and Babylon. Epoch changed and science changed, too.

Nicolasus Copernicus, Giordano Bruno, and Galileo Galilei did a lot of important things for astronomy. This difficult science started developing.

Now, scientists use telescopes for space study. New galaxies and planets are being studied nowadays. The universe is very large in it there are many different stars and planets.

Our planet is Earth. It's the third planet from the Sun. The planet situated in the Solar System. The Sun is a star. The Moon is a satellite of the Earth. Also, in the Solar System there are other planets and asteroid belt. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune are planets. They are different but revolve around the Sun.

The Milky Way is a galaxy where the Solar System locate. It can be notice during a bright night.

Source of image:

https://www.shutterstock.com/es/image-photo/solar-system-planet-comet-sun-star-1029243295



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Universe.

When we see starry night sky, we see a little part of large universe with a plurality of different stars including our sun. The Solar System is also a little part of space. Our planet, Earth, the third from Sun. Neighboring planets such as Mars and Venus have similar similar structure with Earth. For example many, many years ago on the planet Mars, there was life! But now just Earth has living conditions.

Scientists studying universe have found stars which are more bigger than our Sun; main star of the Solar System! Some of them twirl around another planets. But human was not on any other planets apart from Motherland-Earth. But may be in the future people can fly on other planets and even systems.

Universe has dark area and stars with planets. Also planets have one or more satellite of Earth is the Moon.

Sometimes we hear news or stories about UFO or Unidentified flying object. May be it has our "brothers" from another systems or universe. But somebody thinks that all of it simple fiction.

Universe is ome of the greatest mysteries in our history.