Modern humans appeared a little less than 200,000 years ago.
As humanity evolved on the Earth and as the Earth was there for 4600 million years before humanity, the Earth can never have been discovered by humanity.
how long has archaebacteria been on earth? how long has archaebacteria been on earth?
Homosexuality has been a part of humanity since the dawn of humans.
they have been on the earth for along time
It is not possible to determine who the first person to die on Earth was, as death has been a natural part of life since the beginning of humanity.
already has
It has been around since humanity began on Earth (longer if you are talking about animals). There is no record of a first report.
When someone is down to earth
I fear for the future of humanity.
They have been on earth since 190 million years ago.
Well it depends on what you mean. The distance for how long it takes, or the time as in how long since Earth was made. Earth as you know has been here a long long time. Stars light has been shinning towards Earth eversince it was made. To see how long it takes for a stars light to reach Earth depends on how distant and huge the star is.
long time