SsODNet: The Solar system Open Database Network

The sample of Solar system objects has dramatically increased over the last decades. The amount of measured properties (e.g., diameter, taxonomy, rotation period, thermal inertia) has grown even faster. The benefit of all these developments has, however, not come to full fruition. While some catalogs are publicly available in machine-readable formats on, e.g., the Planetary Data System (PDS), or the Centre de Données astronomiques de Strasbourg (CDS), a significant fraction of results are only tabulated within articles. Furthermore, the designation of small bodies often evolves with time, from potentially several provisional designations, to a single number and finally an official name. Hence, the same object can be referred to by different labels in different studies, making its cross-identification over several sources a complex task. Accessing to all the characteristics of a given body, or a population, can thus be tedious, or even impractical. A universal access point for all measured properties of Solar system objects available in the literature and online databases is thus required.

We provide a practical solution to the identification of Solar system objects from any of their multiple names/designations. We also compile and rationalize their properties to provide an easy access to them. We aim to continuously update the database as new measurements become available. We built a Web Service, SsODNet, that offers four interfaces, each corresponding to an identified typical need in the community: name resolution (quaero), compilation of a large corpus of properties (datacloud), determination of the best estimates among compiled values (ssoCard), and statistical description of the population (BFT).

The name resolver quaero translates any of the 5 million designations of objects into their current official designation in a fraction of second. The datacloud compiles about a 100 million measurements of many parameters (osculating and proper element, pair and family membership, diameter, albedo, mass, density, spin, phase function, color taxonomy, thermal inertia, and Yarkovsky drift) from over 2,900 articles. Each parameter is associated with an object, and a complete bibliographic reference is linked with it. For each of the 1.2 million objects in the system, a ssoCard providing a single best-estimate for each parameter is available, and delivered in json format, again in a fraction of a second. Finally, the BFT large table compiles all these best-estimates into a single eCSV file for population-wide studies.

The four interfaces of SsODNet have a Web service with an application programming interface (API). The SsODNet interfaces are fully operational and freely accessible to everyone (https://ssp.imcce.fr/webservices/ssodnet/). We also propose a python package and command-line tool to acces the service: rocks (https://rocks.readthedocs.io/).