# Scientists test radiometer aboard hot-air balloon

Researchers took a radiometer, an instrument that measures radiation, for a test flight in a hot-air balloon. The experiment could help validate the instrument for atmospheric or Earth-observation measurements.

**Importance:** 2/5

## Sources

### Science
- [Nature](https://www.nature.com/articles/d41586-026-02973-9) — 2026-10-06