OpenAI GPT-5.6 Launch: Sol, Terra, Luna Models Released

OpenAI is releasing its latest powerful artificial intelligence model series to the public on Thursday. The new GPT-5.6 offerings include Sol, the flagship model, Terra for everyday work, and Luna, a fast, low-cost option. This comes after the US government reportedly approved a broader launch. These new models, including Anthropic's Mythos series, have raised national security concerns due to their ability to identify code weaknesses. OpenAI had previously shared preview access of GPT-5.6 with limited US-based partners at Washington's request. Terra will be priced at half the cost of its predecessor. This development is important as it could change how AI tools are used and accessed.