Asteroid Magnitudes, UBV colors, Albedos, and Diameters              
                                                                                
                              Edward F. Tedesco                                 
                          Jet Propulsion Laboratory                             
                                  MS 100-22                                     
                              Pasadena, CA 91109                                
                                                                                
     This file is essentially that provided as IRAS Asteroid and Comet Survey   
final data product No. 4 "IRAS Asteroid and Comet Survey: Preprint Version No.  
1 (1986). (D. Matson, Ed.). JPL internal document No. 3698".  Differences       
between that file and MAG-ETAL.DAT are described below.                         
                                                                                
Field (Column)                 Remarks                                          
                                                                                
Asteroid (1) Asteroid number.  Asteroids numbered through 3318 are included.    
             There is one record for each asteroid.                             
                                                                                
H        (2) The visual absolute magnitude from the IRAS ground-based input     
             data set.  These differ from the blue absolute magnitudes (HB)     
             given in final data product No. 4.  In many cases they also        
             differ from those published in the 1988 Russian ephemeris.         
                                                                                
G        (3) The slope parameter from the IRAS ground-based input data set.     
             In many cases these differ from those published in the 1988        
             Russian ephemeris.                                                 
                                                                                
HQ       (4) The quality code for the absolute magnitude and slope parameter.   
             3 is best and 1 worst.                                             
                                                                                
U-B      (5) The U-B color index from IRAS Asteroid and Comet Survey final      
             data product 13.                                                   
                                                                                
UQ       (6) The quality code for the U-B color index as given in final data    
             product 13. (See below)                                            
                                                                                
B-V      (7) The B-V color index from IRAS Asteroid and Comet Survey final      
             data product 13.                                                   
                                                                                
BQ       (8) The quality code for the B-V color index as given in final data    
             product 13. (See below)                                            
                                                                                
UBV Ref. (9) The reference for the UBV color(s):                                
             1 Bowell et al. (1979) In Asteroids (T. Gehrels, ed.),             
                 pp. 1108-1129. ("TRIAD")                                       
             2 Zellner et al. (1985) Icarus 61, 355-416. ("ECAS")               
             3 Weighted mean of values from references 1 and 2.                 
                                                                                
Albedo  (10) Visual geometric albedo from IRAS Asteroid and Comet Survey final  
             data product No. 4                                                 
                                                                                
Albedo Unc.  One sigma formal uncertainty in the visual geometric albedo from   
        (11) IRAS Asteroid and Comet Survey final data product No. 4            
                                                                                
D       (12) Diameter (in km) from IRAS Asteroid and Comet Survey final data    
             product No. 4                                                      
                                                                                
D Unc.  (13) One sigma formal uncertainty in the diameter from IRAS Asteroid    
             and Comet Survey final data product No. 4                          
                                                                                
No. IRAS     Number of IRAS observations used in computing the albedo and       
        (14) diameter (from IRAS Asteroid and Comet Survey final data product   
             No. 4)                                                             
                                                                                
The quality codes for the UBV colors were obtained as follows:                  
                                                                                
                  Quality        For sigma                                      
                   Code                                                         
                                                                                
                     0        >  0.05 magnitude                                 
                     1        <= 0.05 but > 0.03 magnitude                      
                     2        <= 0.03 but > 0.02 magnitude, and                 
                     3        <= 0.02 magnitude                                 
                     4        <= 0.02 magnitude and good agreement between      
                              results from references 1 and 2.                  
                                                                                
For additional details refer to the appropriate chapters in the IRAS Asteroid   
and Comet Survey: Preprint Version No. 1 (1986).