Filters and filter codes used for the APC lightcurve observations:            
                                                                              
   IUE-UV1 Artificial bandpass constructed from the 2627-2747 A portion       
           of the IUE LWP spectrum.                                           
                                                                              
   IUE-UV2 Artificial bandpass constructed from the 2881-3020 A portion       
           of the IUE LWP spectrum.                                           
                                                                              
   GLL-GRN Green filter of the Galileo Solid State Imager (bandcenter=5600 A, 
           width=700 A).                                                      
                                                                              
   GLL-RED Red filter of the Galileo Solid State Imager (bandcenter=6600 A,   
           width=600 A).                                                      
                                                                              
   GLL-VLT Violet filter of the Galileo Solid State Imager (bandcenter=4000 A,
           width=800 A).                                                      
                                                                              
   GLL-MT2 Methane 2 filter of the Galileo Solid State Imager                 
           (bandcenter=8890 A, width=200 A).                                  
                                                                              
   UNK     Unknown filter.                                                    
                                                                              
   OPEN    No filter or clear filter.                                         
                                                                              
   U       Standard Johnson 'ultraviolet' filter (effective wavelength 0.36   
           micron). See Johnson 1965.                                         
                                                                              
   B       Standard Johnson 'blue' filter (effective wavelength 0.44 micron)  
           See Johnson 1965.                                                  
                                                                              
   V       Standard Johnson 'visible' filter (effective wavelength 0.55       
           micron). See Johnson 1965.                                         
                                                                              
   R       Standard Johnson 'red' filter (effective wavelength 0.70 micron)   
           See Johnson 1965.                                                  
                                                                              
   I       Standard Johnson filter (effective wavelength 0.90 micron)         
           See Johnson 1965.                                                  
                                                                              
   J       Standard Johnson filter (effective wavelength 1.25 micron)         
           See Johnson 1965.                                                  
                                                                              
   N       Standard Johnson filter (effective wavelength 10.2 micron)         
           See Johnson 1965.                                                  
                                                                              
   P       Standard Johnson filter (effective wavelength 13.1 micron)         
           See Johnson 1965.                                                  
                                                                              
   U_STROM Stromgren filter (center wavelength 3500 A, FWHM 380 A).           
           See Crawford and Barnes 1970.                                      
                                                                              
   V_STROM Stromgren filter (center wavelength 4100 A, FWHM 200 A).           
           See Crawford and Barnes 1970.                                      
                                                                              
   B_STROM Stromgren filter (center wavelength 4700 A, FWHM 200 A).           
           See Crawford and Barnes 1970.                                      
                                                                              
   Y_STROM Stromgren filter (center wavelength 5500 A, FWHM 200 A).           
           See Crawford and Barnes 1970.                                      
                                                                              
   V_STR2  Modified Stromgren filter (center wavelength 4110 A, FWHM 170 A).  
           See Nielsen 1983.                                                  
                                                                              
   B_STR2  Modified Stromgren filter (center wavelength 4685 A, FWHM 183 A).  
           See Nielsen 1983.                                                  
                                                                              
   X_ECAS  Eight-color asteroid survey filter (effective wavelength 0.853     
           micron, FWHM 0.081 micron) See Zellner et al. 1985.                
                                                                              
   References:                                                                
                                                                              
     Crawford, D. L. and J. V. Barnes. 1970. Standard stars for uvby          
     photometry.  Astron. J. 75, 978-998.                                     
                                                                              
     Johnson, H. L. 1965. The absolute calibration of the Arizona             
     photometry.  Commun. Lunar Planet. Lab. 3, 73-77.                        
                                                                              
     Nielsen, R. F. 1983. A new generation of uvby, H-beta photometer.        
     Inst. Theoretical Astrophys. Oslo, Report No. 59, p141-146.