RE: Share your classroom ideas here

2017-04-29T08:42:16Z

Dear Maria,
Thank you for sharing your ideas! Very interesting!
Kind regards,
Tsetsa

RE: Share your classroom ideas here

2017-04-29T08:22:53Z

Dear Robert,
Black Holes and Big Bang theory are important theories of modern astronomy. To keep up with their content, I use Space Awareness resources (MODEL OF A BLACK HOLE : http://www.space-awareness.org/bg/activities/1304/model-of-a-black-hole/) and Go Lab project’s BHIMS (http://www.golabz.eu/spaces/bhims) for the Black Holes. Stephen Hawking formulates the surprising and illogical thesis that the black holes can thicken, initially slowly, then faster and faster as they explode - an idea that is initially subject to ridicule but is already widely accepted.
According to the Big Bang theory, 13.8 billion years ago, the Universe is in an infinitely tight state with enormous temperature and pressure. The big bang has come from singularity - a point so small and dense that the very laws of physics can not describe it. For the first 10-33 seconds of the universe there is no satisfactory physical model. The actual start of time begins from the Big Bang.
Kind regards,
Tsetsa

RE: Welcome

2017-04-29T06:23:39Z

Hello,
I am Tsetsa Tsolva Hristova from Bulgaria. I am one of Scientix ambasador for my country. My school is computer school, but I have a students like very much Astronomy.
My favorite subject is Astronomy and I am so happy to have possibilities to learn from other colleagues and to share my classroom ideas with you. I use A Brief History of Time by Stephen Hawking at school and shared my ideas with you at Share your classroom ideas here .
Thank you for all great ideas, shared for this book.
Kind regards,
Tsetsa

RE: Share your classroom ideas here

2017-04-25T22:41:27Z

Hello,
This is my idea for astronomical classes with comments:

Historical development of the imagine for construction of the Universe

1.Ancient Greek philosophers ideas

A - Aristotle (340 BC) - the Greek philosopher In his book "For the Heaven," had two serious arguments in favor of the fact that the Earth is round rather than flat
What would be the shadow of Earth on the moon if it is round and if flat, according to Aristotle?
What is the position of the polar star in moderate latitudes and the equator?
Aristotle's understanding of Earth as the center of the Universe that the Earth is stationary, and that the Sun, the Moon, the planets and the stars move in circular orbits around it.

B - Ptolemy ( 2nd century AD) - The Earth is in the center surrounded by the eight spheres bearing the Moon, the Sun, the stars and the five known planets Mercury, Venus, Mars, Jupiter and Saturn

It was perceived by the Christian church as a picture of the Universe that responds to the Scriptures because it has the great advantage of leaving enough space for the heavens and hell outside the sphere of immovable stars.

2. Middle Ages science
A - Nikolay Copernicus (1514), Polish priest - The Sun is stationary in the center, and the Earth and the planets move in circular orbits around it.
B - Galilee (1609) observing the planets moon or moons circling around - it breaks the theory of Aristotle and Ptolemy for the rotation of the planets around the Earth
C - Johan Kepler (1609) altered the theory of Copernicus and claimed that the planets move not in circles but in ellipses under the action of magnetic forces. Finally, the predictions coincide with the observations.
D - Isaac Newton (1687) published his work "Mathematical Principles of Naturist Philosophy"
Newton postulated a law of universal gravittraction, according to which all the bodies in the universe attract each other, with the force of attraction increasing by increasing their mass and reducing the distance between them. This is the same force that causes the fall of the bodieIt is almost certain that the story of Newton and the apple is a fiction. "All Newton said about the matter was that the idea of gravity had occurred to him, while" devoted to contemplation, "was" favored by the fall of an apple " .) Newton showed that, according to his law, gravitation caused the Moon to run in an elliptical orbit around the Earth, and Earth and planets on elliptical paths around the Sun.
The Copernicus model has freed itself from Ptolemy's heavenly spheres, and with them from the notion that the universe has natural boundaries. Since the "fixed stars" apparently did not change their positions, except for their apparent rotation under the influence of the Earth's motion around its own axis, it was natural to assume that the fixed stars are objects like our Sun but far farther.
Newton knew that, according to his theory of gravity, the stars would have to attract each other, so they would not be immobile. And will not they fall down together at any point?

3. The Universe                                                                                                                                 A - ancient cosmologies and Jewish-Christian-Muslim traditions - the universe has emerged at a certain, not too long ago, moment in the past.
B - Immanuel Kant (1781) - The question of whether the Universe has a beginning in time and whether it is limited in space
C - Edwin Hubble (1929) observation that the universe is expanding. And this means that in earlier times the objects were closer together. In fact, it seems that there was time about 10-20 billion years ago when they were all in exactly the same place and when the density of the universe was therefore infinite. This discovery finally raised the question of the beginning of the universe before science.
D - Hubble's observations suggest that there was a time called the Big Bang when the universe was infinitely small and infinitely dense. Under such conditions, all scientific laws, and hence the whole possibility of foreseeing the future, would fail                          For example, the very accurate observations of the planet Mercury showed little difference between its movement and the predictions of Newton's theory of gravity. Einstein's general theory of relativity provides a slightly different movement than Newton's theory. The fact that Einstein's predictions are consistent with observations, while the Newtonians - no, is one of the decisive confirmations of the new theory. However, we serve Newton's theory in practice because the difference between its predictions and those of the general theory of relativity is very small in the cases we usually work on. (Newton's theory has the great advantage of being much simpler than Einstein's!                       Scientists today describe the Universe in terms of two major private theories - the general theory of relativity and quantum mechanics. These are the great intellectual achievements of the first half of this century. General Theory

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RE: Share your classroom ideas here

RE: Share your classroom ideas here

RE: Welcome

RE: Share your classroom ideas here