Solwind

In the two years following the launch of Sputnik, the US was already testing anti-satellite missiles launched from a B-47 bomber.

However, the first successful ASAT missile was in 1985, when a US F-15 fighter launched a specialized missile that destroyed Solwind, a retired solar observatory satellite.

The USSR pursued some very different ASAT paths.

Their Istrebitl Sputnik, literally satellite fighter, was a missile designed to actually enter orbit and maneuver up close to its target satellite before exploding.