Lookup Star

• The Lookup Star Screen assesses an individual star within the large PPM based stellar database. Since each star contained within the database can be referenced by several different identifications, provision is made to specify one of several stellar IDs and searching for a match. IDs by PPM number are completed very quickly, whereas other IDs require more processing time. In addition, provision is made to specify an equatorial coordinate in which case the lookup identifies the star closest to the given position. Once located by any of the methods above, the bottom half of the screen displays all of the information maintained about the star including, when available, the catalog position, visual and photographic magnitude, the various IDs available for the star, proper motion/century and additional notes copied from the source PPM database. Other IDs include ACRS, SAO, AGK3, DM and its sub-components of BD, CD, CPD, and CPC.

• The catalog coordinate information can be updated to any epoch taking into account the catalog proper motion by selecting Upd PM to Date Control. This provides an indication of the effect of proper motion over various time spans. In any case, Asteroid PRO applies proper motion to the date of occultation for all successful searches to maintain the highest possible accuracy in determination of earth shadow paths.

• The database can be perused sequentially by invoking +RA/-RA controls on the left of the screen to move forward or backward in Right Ascension.

• The database itself consists of a combination of a version of the PPM star catalog supplemented by stars from the ACRS star catalog. For the current version, the database is made up of the original PPM North stars plus the original PPM South. The PPM numbers are 1-181731 and 500001-644787; the PPM number is blank for ACRS stars. A later version of the PPM Catalog has been released which renumbers the PPM South to immediately follow the original PPM North and adds additional southern stars. A future version of Asteroid PRO will substitute the star database accordingly and add provision for accessing the Hubble Guide Star Catalog.