This planet was a planet in the Milky Way galaxy who had a Stargate. The planet had no intelligent life, but both plant and animal life, but no signs of living within 80 km radius around the Stargate. On the planet there was an abandoned Goa'uld naquadah mine for several thousand years. And there were still naquadah in the ground.
In 2000, Stargate Command sent a naquadah-enhanced Nuclear warhead to the planet. The bomb detonated, but reacted with the deposits of Naquadah on the planet. This amplified the explosion and turned the whole world to superheated plasma which powered the Stargate, threatening Earth. Fortunately, the gate shut down before it caused a serious threat to the SGC. (SG1: "Chain Reaction")