openai

GPT-5.6 Explained: How Luna, Terra, and Sol Differ

OpenAI's new GPT-5.6 family splits into three named tiers — Luna, Terra, and Sol — under a "scales with your ambition" pitch. Here's what changed, how the tiers are organized, and how it reaches Microsoft 365 Copilot.

07/10/2026 · Model Evaluation · 6 min read

GPT-5.6 "Sol" Explained: What's New, How It Compares to GPT-5, and Why the Rollout Is Restricted

OpenAI previewed GPT-5.6 "Sol" — then limited its rollout after a government request. Here's what's actually confirmed, what isn't yet, and what the restriction signals for frontier-model releases.

06/27/2026 · Industry Trends · 6 min read