NITRO proposal (first time to study nitrogen dynamics in space) was sent to ESA for possible M4 mission candidate, and by The time of EGU we will have known the pre-selection status. No matter whatever the result, we need to discuss the future study to realise such observation (e.g., NASA involvement). We report the status (both science and mission) and have brainstorming. Everybody interested in nitrogen, origin-of-life, ions, and space are welcome.