Were the Dogons visited by aliens from outer space – or somewhere closer?

People who are keen to believe that aliens from outer space have visited Planet Earth at various times in our history sometimes point to the Dogon people of Mali (West Africa) as evidence of such a visitation.

This is because the Dogons appear to possess certain pieces of astronomical knowledge that they could never have worked out for themselves. In particular, they are very well informed about the star Sirius. This was reported by a French anthropologist named Marcel Griaule who studied the Dogon people during the mid-20th century and wrote about them in 1946.

The Dogon people knew that Sirius was a double star, with one of the pair taking 50 years to orbit the other. This was extraordinary knowledge, given that the companion star is too faint to be seen with the naked eye and the Dogons did not have telescopes to look through.

What explanation could there have been for this knowledge? Surely they must have been visited at some time by aliens who lived on a planet that orbited one of the Sirius stars?

Or might it have had something to do with the team of astronomers who had visited Mali in 1893 to view a solar eclipse?