Okay, Kolob its a star, that is said to be nearest to the thrown of God.
From watching a TV program, in the Great Pyramid, in the main burial chamber there is a very small vent shaft that extends up through the north side of the pyramid and it points directly an empty patch of sky, this is the celestial north pole. Which its believe that the shaft was to guide Pharaoh's spirit to the throne of God.
A star watcher will notice that all the stars appear to orbit this point of empty sky, as the Earth rotates. The Celestial pole does not change in respect to Earth's axis of roatation, it remains fixed. Even Polaris (AKA the North Star) is not entirely fixed, it orbits the celestial pole, but there is no other visible stars orbiting it more closely right now.
Polaris means "pole star", other stars have occupied that position in the past (including one with the Arabic name Kochab.)
If the Egyptians viewed this spot of empty space as the location of the Throne of God. The closest star to it would be the star the was the pole star at the time.
Egyptians even as "apostates" had still held many beliefs as Abraham, (as the "Egyptian" god Amen-Ra is Jehoveh ("Amen" Rev. 3:19)), so what I think is possible is that "Kolob" was a pole star of Abraham's time, the one "nearest to the Throne of God", the Celestial pole. The Egyptians viewed the celestial pole as the throne of God because everything appeared to rotate around that point, and the closest star would rule every other star, other stars seem subject to it.
The star that was designated by Abraham as Kolob would not be today's Polaris, but one of the other past "pole stars". The current pole star is Alpha Ursae Minoris. and would be closest to the Throne of God today, therefore "today's" Kolob.
The Book of Abraham gives the impression that such the nature of the universe, but it doesn't square with the arrangement of the universe as those who lived after the days of Copernicus, Galileo, and Newton.
However, if we were to think the Pole Star was Kolob, viewed the celestial sphere as flat, and a had beliefs in relation to Egyptian thought, it then makes some sense.
This is not considered to be official church doctrine at all, you recall the popular "rumor" that Lost Tribes had went to the North Star?
We are told by a son of Anson Call, a particular friend of the Prophet, that Joseph told him in company with others on a number of occasions that the ten tribes were on a portion of the earth that had been taken away. There is also a statement attributed to the grandson of a man with whom the Prophet once stayed. In response to his grandfather's question as to where the ten tribes were, Joseph Smith reportedly took him outside and pointed to the north star. I know most members now days think that thoughr=t is a bit outragious and consider it misunderstood or ill-reported, but in light of this theory, its seems interesting to me, as to what reason he thought the north star had signifigance.