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  • What data is incorporated into neoproperties.nasa.gov?  Where does it come from?
  • Neoproperties aggregates data from other websites, PDS data products, web resources and peer reviewed publications.  The current version of the neoproperties database is 2018.5.  A list of all the data sources included in this version is found here.
  • Why are there more NEOs reported at other websites?
  • neoproperties is focused on providing physical properties.  Organizations that are focused on NEO identification and orbit refinement include MPC and JPL's  Horizons.   If you want the most recent count of the number of known NEAs or the latest orbital parameters, check out their sites.   (There are a lot of additional excellent resources available here.)
  • How should I reference information from neoproperties?
  • When using data obtained from neoproperties, the user is strongly encouraged to reference both  neoproperties.nasa.gov  and the original data source for the value(s).  References for the original data source should be available via the summary table and single object view.  If there are any questions as to the original data source, please don’t hesitate to  contact us.
  • When there are multiple measurements, how do you decide what to display in the summary table?
  • For the meteorite data set, all separate measurements are listed as individual entries.  The NEO data set follows a set of rules to determine which measurement to display.  The goal of the rules for diameter measurements is to select the measurement with the highest signal to noise.   All unique taxonomy assignments are available in the summary table, but the most prevalent complex will be chosen to be displayed in the summary table.
  • How do you calculate asteroid diameter?
  • In the case where no thermal measurements exist, diameter is calculated following the rules outlined here.  The diameter measurements currently incorporated into neoproperties are based on thermal infrared measurements and the NEATM model.  Additional details can be found by reading the references for the diameter data sources.
  • What about other methods of measuring an asteroids diameter?
  • In addition to diameters derived from thermal infrared photometry, radar and stellar occultations provide excellent measurements of asteroid diameters.   Currently, the focus of neoproperties is to include thermal diameters.  Diameter measurements from other methods will be included in future builds.
  • How do you identify which meteorites correspond to which asteroids?
  • In order to identify which meteorites correspond to which asteroids, we have relied on a variety of sources in the literature.   The full mapping and the references can be found here.
  • How do I submit data for inclusion in the neoproperties database?
  • Email us at  neoproperties@lists.nasa.gov.  We  love new data!