That figure of 10 to 15 kJ can be very misleading about what it takes to propel something to such speeds. Put into 'TNT equivalent', it would take the entire en

That figure of 10 to 15 kJ can be very misleading about what it takes to propel something to such speeds. Put into 'TNT equivalent', it would take the entire energy of 50g of TNT to boost a 100g bolt by just 2 km/s. It's difficult to concentrate that much energy per mass in an explosion (which is leaky). To add further, most ASATs (including the Indian test) doesn't use explosives, but make a direct hit (hit to kill) from a suborbital trajectory (one that has much less energy than an orbital interceptor). The boosting comes mostly from fragmentation mechanics. The satellite will still fragment with some fragments getting boosted up to a higher velocity. In addition, the propellants on the satellite and the kill vehicle might add velocity to the fragments too - though arguably less energy than if it was TNT. So, previous studies on US and Chinese ASAT debris cloud can be considered for a fair assessment. The Chinese test was at a higher altitude of 865km and US test was at a similar altitude. 'Gabbard plot' of these debris show the maximum altitude to be only around 3900 km for both tests. There could be untracked particles at higher orbits, but remember that the velocities of the debris is a random distribution (not sure which one) that tapers at extreme values. Odds of any debris crossing geostationary orbit is very low. There is one additional significant point to consider. Boosted orbits mostly retain the altitude at interception (it's the diametrically opposite part of the orbit that gets affected). This is evident from the Gabbard diagram, where apogee and perigee plots intersect in cross shape with a horizontal line at the altitude corresponding to intercept altitude. This means that most debris come down to atleast 300km. Since the drag at this point is significant, the apogee (maximum altitude) of the debris would decay rapidly - thus mitigating risk to higher satellites. With that odds, a debris crossing geostationary orbit could more likely be from some previous in-orbit explosions than from any ASAT test. Ref: https://sattrackcam.blogspot.com/2019/03/debris-from-indias-asat-test-how-long.html https://sattrackcam.blogspot.com/2019/03/debris-from-indias-... https://sattrackcam.blogspot.com/2019/04/why-even-low-altitude-asat-intercepts.html https://sattrackcam.blogspot.com/2019/04/why-even-low-altitu... https://celestrak.com/publications/AMOS/2007/AMOS-2007.pdf https://celestrak.com/publications/AMOS/2007/AMOS-2007.pdf