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Ephemerides

Images for the paper U.S. Naval Observatory Ephemerides of the Largest Asteroids
Image GIF image Mass determinations of Ceres
Figure 1. The history of mass determinations of 1 Ceres.
Image GIF image Mass determinations of Pallas
Figure 2. The history of mass determinations of 2 Pallas.
Image GIF image Mass determinations of Vesta
Figure 3. The history of mass determinations of 4 Vesta.
Image GIF image Residuals for 1 Ceres
Figure 5. Residuals for 1 Ceres. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 2 Pallas
Figure 6. Residuals for 2 Pallas. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 3 Juno
Figure 7. Residuals for 3 Juno. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 4 Vesta
Figure 8. Residuals for 4 Vesta. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 6 Hebe
Figure 9. Residuals for 6 Hebe. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 7 Iris
Figure 10. Residuals for 7 Iris. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 8 Flora
Figure 11. Residuals for 8 Flora. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 9 Metis
Figure 12. Residuals for 9 Metis. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 10 Hygiea
Figure 13. Residuals for 10 Hygiea. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 15 Eunomia
Figure 14. Residuals for 15 Eunomia. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 16 Psyche
Figure 15. Residuals for 16 Psyche. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 52 Europa
Figure 16. Residuals for 52 Europa. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 65 Cybele
Figure 17. Residuals for 65 Cybele. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 511 Davida
Figure 18. Residuals for 511 Davida. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Residuals for 704 Interamnia
Figure 19. Residuals for 704 Interamnia. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period.
Image GIF image Complete Residuals for 3 Juno
Figure 20. The complete residuals for 3 Juno. The red bars indicate the 3 sigma deviation for the residuals in each twenty year period, and the green numbers are the number of observations in that period. Before 1839 there is systematic slope to the residuals in right ascension before 1839. By 1807 the deviation from 0 is 2."1 or 2/3 sigma.
Image GIF image Diff. in App. Pos. between Duncombe and USNO/AE97 for Ceres
Figure 21. The difference in apparent position between the Duncombe ephemeris and USNO/AE97 for 1 Ceres.
Image GIF image Diff. in App. Pos. between Duncombe and USNO/AE97 for Juno
Figure 23. The difference in apparent position between the Duncombe ephemeris and USNO/AE97 for 3 Juno.
Image GIF image Diff. in App. Pos. between Duncombe and USNO/AE97 for Pallas
Figure 22. The difference in apparent position between the Duncombe ephemeris and USNO/AE97 for 2 Pallas.
Image GIF image Diff. in App. Pos. between Duncombe and USNO/AE97 for Vesta
Figure 24. The difference in apparent position between the Duncombe ephemeris and USNO/AE97 for 4 Vesta.