how did the ancients know that the little lights in the sky were stars? how could they know that?

Answer 1

obvious intel.

Answer 2

It was Democritus, a philosopher born in Thrace in 460 BC, who came up with this theory. He also suggested that all matter was made up of different elements, which consisted of basic building blocks called atoms. Pretty on-the-ball of him for someone who lived nearly two and a half millennia before Mendeleev and Rutherford!

Democritus was also the first philosopher we know who realized that the celestial body we perceive as the Milky Way is formed from the light of distant stars. Other philosophers, including later Aristotle, argued against this. Democritus was among the first to propose that the universe contains many worlds, some of them inhabited:

"In some worlds there is no Sun and Moon, in others they are larger than in our world, and in others more numerous. In some parts there are more worlds, in others fewer (...); in some parts they are arising, in others failing. There are some worlds devoid of living creatures or plants or any moisture."

So whilst Democritus had a pretty astute mind, the ancients as a whole did not support his ideas. They only caught on later as modern science developed and made sense of his propositions, He was simply "a man ahead of his time".

Answer 3

Anyone who could see could see those lights at night, anyone who could talk or write could make up stories about them. We still use those stories, either to memorize what lights are where or to tell morality tales, pass down cultural lore, or just entertain.
Careful observation and thinking made those lights useful for calendars, clocks, and navigation. This same sort of thinking and observation came to change our visualization of the universe and we started calling it science. Galileo and Newton, amongst others, changed our understanding by seeing that the same laws that govern things on earth govern the stars. We are still learning important science from looking at the stars and thinking about the rules that govern them. It is almost pure mathematics subjected to the severe constraint that the theory has to correspond to what we can see in the universe.

Answer 4

They didn't. All they knew was there were lights in the sky, some of which moved around and were called planets. In parts of Africa people thought they might be the campfires of other beings, and they saw us as another star in their skies. That notion I kind of like because not only is it romantic, but actually close to the truth since stars are like campfires to their planets.

Answer 5

Simple. We time traveled back there from the future and told them. Or it was extrataresterials. Or they were smarter than you give them credit for being. Take your pick.

Answer 6

Because the beings whom came from other planets told them shem so.

Answer 7

Depends on what you mean by ancients.
God had writers that he spoke to who wrote down the words He gave them. This is how we received the Bible. It was written by Jehovah God through men such as Moses, Isaiah, Jeremiah, Matthew, Peter, and others. See what Genesis, the first book in the Bible says;

14 And God went on to say: “Let luminaries come to be in the expanse of the heavens to make a division between the day and the night; and they must serve as signs and for seasons and for days and years. 15 And they must serve as luminaries in the expanse of the heavens to shine upon the earth.” And it came to be so. 16 And God proceeded to make the two great luminaries, the greater luminary for dominating the day and the lesser luminary for dominating the night, and also the stars.

So when these writings became available to earthling man, approximately 3500 years ago, all people who had access to the scriptures knew they were called stars, according to the Creator of them.

Also, and maybe more interesting, man knew they were called stars from very early on because before the written scriptures were availab;e, God himself spoke directly with certain men. Men like the faithful Abram. Look at this account in Genesis 15:5.

15 After these things the word of Jehovah came to A′bram in a vision, saying: “Do not fear, A′bram. I am a shield for you. Your reward will be very great.” 2 At this A′bram said: “Sovereign Lord Jehovah, what will you give me, seeing that I am going childless and the one who will possess my house is a man of Damascus, E·li·e′zer?” 3 And A′bram added: “Look! You have given me no seed, and, look! a son of my household is succeeding me as heir.” 4 But, look! the word of Jehovah to him was in these words: “This man will not succeed you as heir, but one who will come out of your own inward parts will succeed you as heir.”

5 He now brought him outside and said: “Look up, please, to the heavens and count the stars, if you are possibly able to count them.” And he went on to say to him: “So your seed will become.”

So Jehovah himself told Abram to count the "stars" in the language of that day. From that language, what we now call early Hebrew, mankind was able to translate their word into "stars" from God's original name for them.

I hope that helps somewhat.

God Bless and thanks for reading.