This "apearance of age" idea was first suggested for geological data by Phillip Gosse a hundred years ago. It is still a popular idea for many such aspects of nature that appear old: that the result of a recent mature creation gives an appearance of age but it is not really so old. In the case of SN1987a, God simply made the star fully formed at a distance of 170,000 light years but with its light already at the earth from the very beginning.

The problem many would have with this is that if God created stars at such a distance, and  intentionally created the starlight already at the earth from the beginning, then in this case (and many others as well), He would have had to encode the starlight with the history of an event (the change from normal star to explosion) that never actually happened - it just "appears" to have happened. If the universe is only a few thousand years old, this supernova has always been a supernova and never an ordinary star. But up until 1987 it was seen in the starlight to have been just an ordinary star. If God altered the history of this part of His creation to appear to be something it wasn't, who's to say what history is real and what history is fake? And why would God tell us to go look at natural history (Romans 1:19-20) to learn about His godly nature and power if natural history doesn't record true history? This would seem to be a problem since that same God tells us He cannot lie -- Hebrews 6:18, Titus 1:2.

I will not accept that God is a liar, even if its just a little "white lie" to astronomers. Therefore, I don't think God faked this event in the starlight. It must have really happened 170,000 years ago.