Recently , Some Nasa's Scientists were in talks about aliens and UFOs . They said:
"Ufo's aren't seen before the nuclear war , but  when the first nuclear war had started then after one year there were people claiming they had seen some mysteries objects on sky, in a saucer shape . And from then only many UFOs cases came around from all over the world . Aliens are there , but they are not smart or clever then us."
As we all know nuclear weapons are the best creation of the cold war era but does it have any affects on space ? Some also says that the planets which are light years far away from earth can also see the radiations in space as it effects space. It is believed that UFOs came here from far distance to help earth from preventing us from future wars.

In 1960's a group was formed known as "Majestic12 " (MJ12) . This the group in which the president of America too was involved . This is the group which was formed to establish contact with ET's.

  Rumor was that they tried to contact with ET's of other planets and all of a sudden a UFO crashed near Roswell in 1940's. This means some of the people know how to contact and maybe they are calling them for a reincarnation of the human race.

Dulce Base is the place which is known to have an underground area where there might be aliens captured. In 1970, at dulcebase during the coldwar... Some people said they fought with Grey's. Some of them died and only 2 persons got out alive. One of them was the famous person " Phil Schneider " who lost his finger during that war and suffered from antique type of radiation.

He was the one who came in media and said what actually happened on that day . and later he died in 1996, his death was a mystery ( was not a suicide ). From that time people named these type of alien species as Grey aliens .