Scott Manley dropped a video on the Russian Noodle test. He briefly mentioned how the Indian ASAT test had just one piece of debris left in orbit after 2 years.
Shooting a missile or whatever weapon to destroy a satellite doesn't equal ASAT capability.
A massive land/sea/sky based supervising network;
Decades accumulated data of monitoring foreign space objects' activities in the space;
A well planned/equipped, fully trained space war force.
For now, US is the only country has the full capability, Russia has a limited one, China is still working in the progress, India just starts.
1.) We have intel sharing agreement with USA that includes space situational awareness.
2.) Most satellite data is made public by USA for civilians around the globe.
3.) India's Space Fence is being built as we speak.
4.) A full fledged Space Force would have co-orbital killer satellites, among other assets. What is being talked about is an ASAT capability which can only target satellites orbiting directly overhead. India is very capable of tracking satellites over its airspace and targeting them with an ASAT. Work on co-orbital killers and military rockets to launch them has also started. There is a Defence Space Agency in India which is basically a nascent Space Force since its under a two-star general. Some time next decade it will be upgraded to a Space Command under a three-star General and then maybe by 2050 we see an Indian Space Force under a four-star general. So its not wrong to say that India has ASAT capability.
5.) Future Indian destroyer classes will have radars like DRDO LRMFR, powerful enough to track satellites flying over them and will also have the required missiles that can shoot them down (at least for LEO sats) AD-2. Meaning India will become able to shoot down satellites avoiding overflying Indian airspace.
6.) We should all remember that MAD is equally applicable to Kinetic Kill of satellites as it is to Nukes.
If you know the mass and velocity of the object at any point, you can accurately calculate its trajectory. Basic Newtonian mathematics.
They don't even need radars or stuff like that.
Not that simple. There is a drag that alters trajectory because LEO isn't exactly vacuum. There is some atmosphere there which is why satellites need to do station keeping burns from time to time. The deviation in the orbit due to the drag is somewhat unpredictable.
And even without the air drag, with simple Newtonian Mechanics, there is the problem that the satellite is in the Earth Moon system, making its orbit a three-body problem. Most three-body problems don't have an analytical solution, meaning you only get a numerical solution i.e. an approximation, which drifts from the real value if you don't keep tracking it at least intermittently.