Check on JPL DE405 using modern optical observations
Royal Greenwich Observatory, Madingley Road, Cambridge CB3 0EZ, UK
Send offprint request to: L.V. Morrison
Accepted: 12 May 1998
JPL DE405 is compared with optical positions of the outer planets Jupiter to Pluto. Systematic errors in some of the optical observations complicate the interpretation of the residuals between observation and DE405. A common offset in the right ascension of the outer planets suggests a frame–tie problem between DE405 and the ICRF. It is concluded that the overall accuracy of DE405 is better than 50 mas for these planets in the period 1984–1997.
Key words: astrometry / major planets / ephemerides
© European Southern Observatory (ESO), 1998