Answer:
1. 100 CE
Menelaus of Alexandria lived. a Greek mathematician and astronomer
2. 190 BCE - 120 BCE
Hipparchus of Nicea, an Hellenic language mathematician, astronomer and geographer, regarded by many historians as a scientist of the most effective quality and one amongst the most effective astronomical genius amongst ancient Greeks.
3. 276 BCE - 195 BCE
Eratosthenes, an Hellenic language Alexandrian scholar, who was a native of Cyrene and one amongst the most effective geographers in antiquity.
4. c. 310 BCE - c. 230 BCE
Aristarchus of Samos. A Greek astronomer and mathematician
5. 384 BCE - 322 BCE
Aristotle Era.
6. c. 571 BCE - c. 497 BCE
Pythagoras of Samos lived during this era.
7. 585 BCE
Media and Lydia went into battle and broke off immediately as a result an entire eclipse of the sun which occurred causing the two armies to create peace. The eclipse was already predicted by Thales of Miletus.
8. 585 BCE
Thales of Miletus lived during now.
Explanation:
Ancient Greeks were some of the first people known to study the sky and understand what astronomy really entails. They discovered the Earth was spherical in shape and went ahead to devise a means to measure its size. They also were the ones who created the idea of a geocentric solar system, which was incorrect, But assisted us in understanding the universe for over hundreds of years.
Mechanical Wave cannot travel in space vaccumes, which would be considered "Empty Space" in your situation.
acceleration is considered to describe an increase or positive change of speed or velocity But deceleation is considered to describe a decrease or negative change of speed or velocity
Answer:
Explained in Depth.
Explanation:
It is all matter of what kind of stars are we talking about, for simplicity let's say we are talking about normal stars such as our sun.
If there is a molecular cloud that has a mass that is slightly larger than our sun then it is possible that the gravity will eventually pull together cloud into a sphere that would have enough mass to start nuclear fusion which is important to become a star.
Mass of such cloud would be 1.98x10^30Kg almost equal to the sun's mass.
All of this implies that stars are formed when there is enough mass to let gravity pull it all together into a sphere that has enough gravitational pull to start nuclear fusion inside the core.
