Appendix A: Comparative Tables

Table 1. Energy comparisons.*

           Energy, J           Energy, Relative

Two 3,500-lb. cars colliding head-on at 55Jmph
           9.6 x 10^5          1

Explosion of 1 U.S. ton of TNT
           4.2 x 10^9          4,271

Explosion of a 20-megaton fusion bomb
           8.4 x 10^16         87,500,000,000

Total U.S. annual electric power production, 1990
           1 x 10^19           10,400,000,000,000

Energy released in last second of 10^13 kg fragment of Shoemaker-
Levy 9
         ~ 9 x 10^21           9,375,000,000,000,000

Total energy released by 10^13-kg fragment of Shoemaker-Levy 9
           1.8 x 10^22         18,750,000,000,000,000

Total sunlight on Jupiter for one day
           6.6 x 10^22         68,750,000,000,000,000

Table 2. Power comparisons.*

Power Producer    Power, MW        Power, Relative

Hoover Dam        1,345            1

Grand Coulee Dam, final plant
                  9,700            7.2

Annual average, sum of all U.S. power plants
                  320,000          238

Average, impact of 1013-kg fragment of Shoemaker-Levy 9,
final sec       ~ 9 x 10^15        6,700,000,000,000

Sun               3.8 x 10^20       280,000,000,000,000,000

Object                    Radius, km               Volume, km^3 

Jupiter                 71,350 (Equatorial)        1.4 x 10^15
                        67,310 (Polar)

Earth                   6,378 (Equatorial)         1.1 x 10^12
                        6,357 (Polar)

Comet Shoemaker-Levy 9  4.5 (Equivalent sphere)    382

Comet Halley            7.65 x 3.60 x 3.61         365

Table 4. Brightness comparisons.

Object  Magnitude Vo(V Mag. at Opposition)     Relative Brightness
		
Largest fragment of Shoemaker-Levy 9 during last second
        ~ -10                                  1,000

Jupiter   -2.5                                 1

Ganymede   4.6                                 1/692

Io         5.0                                 1/1,000

Largest fragment of Shoemaker-Levy 9 as viewed today
           23.7                                1/30,000,000,000