IAUprovisional

IAUprovisional is a term sometimes used to describe the provisional designation process employed by the International Astronomical Union (IAU) for newly discovered astronomical objects before their orbits are confirmed or a permanent name is assigned. It is not an official product name, but it references the interim identifiers that allow researchers to refer to objects during early observations and data collection.

Scope and authority

Provisional designations are issued by the IAU’s Minor Planet Center (MPC), which coordinates the collection and validation of astrometric observations for minor planets and comets. The designation system provides a unique label that persists as additional data are gathered, even if formal naming is pending. The IAU oversees the framework to ensure consistent identification across observatories and catalogs.

Format and purpose

Provisional designations follow a year-based code that encodes the time and order of discovery. The label begins with the year, followed by letters that indicate the half-month of discovery and the sequence of discoveries within that interval, with additional numbers used when needed. The exact form can vary by object type and discovery context. The primary purpose is to unambiguously reference objects while their orbits are refined and their dynamical status is established.

Lifecycle

A newly reported object may receive a provisional designation as observations accumulate. If the orbit becomes well determined, the object may be assigned a permanent number and, in many cases, a name. If the object remains unconfirmed or loses a reliable trajectory, its provisional designation may be retired or replaced as records are updated. For comets, similar provisional labeling exists within the IAU framework, with subsequent naming following organizational guidelines.

See also

Provisional designation, Minor Planet Center, International Astronomical Union.