TNO
TNO is an acronym with multiple uses in different domains. In astronomy, Trans-Neptunian Object refers to any minor planet or other small body that orbits the Sun at a distance beyond Neptune, roughly beyond 30 astronomical units. Most TNOs reside in the Kuiper belt or in more distant populations, and they exhibit a variety of orbital classes, including resonant, classical, scattered-disc, and detached objects. They are typically icy and dark, reflecting only a small portion of sunlight. The study of TNOs informs models of the early solar system and planetary migration. Notable members include Pluto, Eris, Haumea, Makemake, Orcus, Gonggong, and Sedna; several are classified as dwarf planets. Ongoing surveys and occultation measurements continue to refine estimates of their sizes, compositions, and atmospheres.
The Netherlands Organization for Applied Scientific Research, known by its Dutch acronym TNO (Nederlandse Organisatie voor