Everything that exists is a part of Space. Space is an endless void which consists all the stars, planets, galaxies and practically everything. Space begins when Earth's atmosphere ends. In the ancient times it was believed that Space was empty however, with time it was proved that it consisted of innumerable galaxies (and everything which existed in galaxies) and vast amounts of gas and dust. Even the emptiest parts of space contain some amount of gas and dust.
The Big Bang theory is the most likely theory which explains the birth of our universe and is widely accepted by most scientists of the world. It states that the Universe began as an extremely hot and dense singularity and rapidly expanded over a period of 13.8 billion years to the state that it is today. This theory was proposed by Russian mathematician Aleksandr Friedmann and Belgian astronomer Georges Lemaitre and was proved when two physicists (Arno Penzias and Robert Wilson) discovered Cosmic Microwave Background Radiation (CMBR) - The Primary Light or 'Afterglow' of the Big Bang.
Valantina Tereshkova :
First women in space -Soviet Citizen -1963
Alan Shepard :
First American and second person in space -1961
First American women in space -1983
Alexei Leonov :
First soviet cosmonaut to conduct extravehicular activity in space(Spacewalk) -1965
Pham Tuan :
First Asian-Vietnamese in space -1980
Neil Armstrong :
First human to walk on moon -1969
Buzz Aldrin :
Second human to walk on moon -1969
First Chinese person in space .
First self funded space tourist-2001
With the humans now capable of entering space and having an access to it certain rules and laws are put in place to protect space as well as themselves, these are known as space laws.
In the current circumstances, if any country finds land which is unexplored, uninhabited , it can legally claim the land as a part of their country. However, when it comes to space, this rule is not applicable. The space right above a particular country cannot be considered as a part of their country, neither can any unexplored space territory can be claimed by that country.
Ban of nuclear testing
When the intention to carry out any nuclear tests in space became evident, a treaty was signed to prohibit it.
The Outer Space Treaty is a treaty that puts certain restrictions on countries carrying space exploration. The directives of this treaty are:
The Sun was formed about 4.57 billion years ago from the collapse of a giant molecular cloud that consisted mostly of Hydrogen and Helium. Many studies show that one or more supernovae must have occurred nearby the area where the sun was formed. A shock-wave from a nearby supernova could have triggered the formation of our sun by compressing the matter within the molecular cloud and causing certain ares to collapse under their own gravity. Most of the matter gathered at the centre, whereas the rest flattened into an orbiting disk. Gravity and pressure within the core generated a lot of heat as it accumulated more matter from the surrounding disk, eventually triggering nuclear fusion. Hence our sun came into existence