∞ generated and posted on 2016.08.18 ∞

Radiating microtubular array that surrounds centrosomes in animal cells during mitosis or meiosis and that is visible through a light microscope.

An Aster is seen during eukaryotic cell division, mitosis or meiosis, as a pair of star-shaped structures where the center of the star is a centrosome and microtubules are the points radiating from that center.

The significance of asters mostly stems from this structure being prominent when studied using a light microscope. Otherwise they mark the position of the centrosomes and also provide a hint as to the density of microtubles, that is, number of microtubules projecting from those centrosomes, thus forming the mitotic spindle.

In the following video the asters can be seen in the upper-left of the cell starting at 0:18 seconds: