OpenAI has officially launched its GPT-5.6 series models, expanding access to the public following an earlier limited preview. The new models, named Sol, Terra, and Luna, are now available on platforms including ChatGPT, Codex, and API. Pricing for the models is structured per million tokens, with the Sol model priced at $5 for input and $30 for output, the Terra model at $2.50 for input and $15 for output, and the Luna model at $1 for input and $6 for output.