[Physicist]

Anyhow, be more specific if you want me to answer your dating that you so precisely stated as 150,000 years old.

We know how far away the Large Magellanic Cloud is because of how bright the stars are as we see them from here. Specifically, stars called Cepheid variables are used, because we can determine their absolute brightness by measuring their period of variation. But in any case, you can tell immediately that the LMC is very far away, simply because of the dimness and angular proximity of its stars. Even young-earth creationists admit that other galaxies are far away; if they were very close by, there'd be no need to postulate that the speed of light has changed.

Enter SN1987a. After it exploded, a shockwave of light and neutrinos went flying away from it. As it propagated outwards, it illuminated interstellar matter, which allows us to measure its progress as it moves perpendicular to our line of sight. IF we postulate that light moved much faster back then, we would see the shockwave propagate outwards very quickly, many light-years per year. Our measurement of the distance to the LMC with Cepheid variables is accurate to maybe 10%, more than good enough to distinguish between a normal speed of light and a vastly greater speed of light. Notice how I haven't said anything about how long ago the explosion occurred: the measurement of the speed of light back then depends only on how far away it was, and how big the shockwave appears to us after 14 years of expansion.

It is an experimentally measured fact that the speed of light in the Large Magellanic Cloud back when SN1897a occurred--whenever it may have occurred--was not significantly different from what it is now. Having conclusively established the stability of the speed of light, we are now at liberty to use it to calculate how long ago it occurred. At a measured one light year per year, that would mean SN1987a occurred 150,000 years ago.

[bryan1276]

In short, the answer is that there is nothing observable that exists today that is more than about 6,000 years old. I always get a kick out of folks who take the phrase "be more specific" to mean "use bigger words to make it sound credible." You're restating what was said a while ago, and as was already answered in previous posts, you have assumptions built on assumptions. You're still telling me that you assume "x" and the deviant from that is what you further assume to be translated into age. Now, we know nothing exists in this universe that is anymore than 6,000 years old because the Creator of the universe has said so. What you are doing with star dates, and dates are important here because it's how you are measuring the speed of light, is exactly what geologists do with the earth. Date the layer by the rocks and date the rocks by the layers. You know how they do it: "Its a fact that this layer is 10,000 yrs old" Says who? "Because we know its a fact that this fossil we found in it is 10,000 years old." Says who? "Because we know its a fact that the layer it was found in is 10,000 years old." See how the game is played. Just add some terms like paleozoic and strata and suddenly the circuity of the argument seems to be lost in the rhetoric.