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urzu_seven t1_jd6tds4 wrote

Yes and no.

Yes (mostly) - the time, in absolute terms that the earth takes to complete one lap around the sun has been close to the same. Orbital period is determined by an objects distance from the sun. The Earths average distance from the sun has been basically the same since its formation, meaning its orbital period has been the same.

No - We typically measure years in number of days (roughly 365.25 right now) it takes for the Earth to complete one orbit. While the overall length of orbit in say, seconds has not changed, the number of days it takes HAS because the Earths rotation is slowing down. Billions of years ago it probably took less than 20 hours for the Earth to complete one rotation, aka one day. So the number of "days" in the year was greater, as each day was shorter.

So in raw time, yes, its basically the same. In terms of how many "days" it took? No, it used to be longer.

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