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Use an Ephemeris Generator to Find the Right Ascension, Declination, and Magnitude of Ceres

NASA’s Near Earth Object program provides an orbit diagram of Ceres.

The Solar System Dynamics Groups at the Jet Propulsion Laboratory has an online Solar System data and ephemeris computation service. An ephemeris is a table giving the position of celestial objects at different times and from different observing sites. The service provides access to highly accurate ephemerides for Solar System objects. An ephemeris table gives the position of celestial objects at different times and from different observing sites. Use the following procedure to find the right ascension and declination of Ceres on any date.

1. On a computer with Internet access, go to: http://ssd.jpl.nasa.gov/horizons.cgi
2. Click on the button that says “Target Body.”
3. Under “Select Small-Body,” enter “Ceres,” then click “Asteroids Only” and “Search.” Choose “Asteroid 1 Ceres” from the drop-down menu, then click on “Use Selected Asteroid/Comet.”
4. Click on “Observer Location.”
5. Under “Lookup Named Location,” use the “Choose US Cities from a List.” Choose the town or city that is closest to your location. Then click on “Search.”
6. Click on “Time Span.”
7. Enter the start date and time as the local time that you will begin observing.
8. Enter the stop date and time as the end of the same day for a desirable observing time interval (local time).
9. Click on “Use Specified Settings.”
10. Click on “Output Quantities and Format.”
11. Choose Number 1, “Astrometric RA and DEC,” and Number 9, “Visual Magnitude and Surface Brightness,” and Number 29 “Constellation ID.” De-select all other check boxes.
12. Choose “Suppress Output During Daylight.”
13. Click on “Use Specific Settings.”
14. Click on “Generate Ephemeris.”

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