Young-earth "proof" #8: At the rate many star clusters are expanding, they could not have been traveling for more than a few thousand years.

8. Not having the references, I have no idea as to what this argument is all about! I can't make heads or tails out of it.

I believe that some creationists have argued that many stars in a typical globular star cluster are moving outward, thus limiting the cluster to a certain age before it dissolved. Such an argument betrays a gross ignorance of globular clusters. A given star moves away from the central area of a globular cluster for a time, but it slows down, reverses direction, and falls back through the central region of the cluster and out the other side. Thus, stars move back and forth through the center of the cluster. There is no net expansion there.

Globular clusters do, however, present a stunning proof of great age! To reasonably understand the details of this proof, you should read Dalrymple (1991, pp.365-375). I'll quote from Dr. Alan Hayward to sum up the central idea.
 

[Scientific] techniques have enabled astronomers to work out the life span of each particular kind of star. They have found, for example, that the hottest and brightest blue stars were endowed with only enough energy to keep them going for a few million years, whereas the coolest red stars have a life span of many billions of years.
 

Some clusters contain stars of all life spans, from the shortest to the longest. Some contain all except the very shortest-lived types. Some contain all except very short-lived and fairly short-lived types. And so on, all the way to those clusters where only the long-lived types are present.

But never do we find a cluster without a selection of the long- lived types. The missing ones are always from the shorter end of the range. We can look at the data for each cluster and say, 'This particular cluster contains only those types of stars with life spans greater than x years', where x has a different value for each cluster. (Hayward, 1985, p103)

The explanation is quite simple. Originally, when each globular cluster formed it was populated by a variety of star types as might reasonably be expected. As it aged, the first stars to disappear were the shortest-lived stars, and they were followed by the short-lived stars, until, in the very oldest globular clusters, only the very old red stars remained.

Since this conclusion is based upon a great mass of experimental data it seems inescapable, unless we are prepared to write off the extraordinary distribution of star types in clusters as a mere coincidence. And the odds against that have been calculated to be countless millions to one. (Hayward, 1985, p.104)

Thus, the odd distribution of stars in the globular clusters is a result of great ages at work. Most globular clusters, based on the above and other factors, appear to be more than 10 billion years old! (Chaisson and McMillan, 1993, p.411). Far from being an argument for a young universe, globular clusters are a showcase for an old universe.