Huge 'sky explosion' investigated

There is no doubt that HAARP is semi-secret.
Look at what they are capable of!
It is an incredible feat of modern inginuity.
That being said, there is NO DOUBT that the military will utilize its potential.

I'm quite sure that they DO test it from time to time.

The electrical currents involved are incredible! And they send them up into the upper-atmosphere.
Problem is, I'm not sure they understand what will become of their tests.
They would be very wise to study this thing closely until they gain more knowledge.
Gradually building themselves upwards until they know if they can, or most likely cannot, use it in a large-scale manner.

I still see no reason to suspect this was HAARP related.

And all of the above reiterates the point that their research, at least on its face, has no reason to be secret.
Aside from the fact that the complex can be easily seen for miles.

It isn't like Area51 where they are in the middle of a vast lake bed. They are surrounded by mountains with good visibility conditions.
Hell, the compound isn't even sealed off, unless I'm mistaken.

They have no need to make this secretive, until they figure out how to rule the world with it.