If you find any asteroid with a sufficient magnesium hydride (or any other useful substances that could help you terraform Venus), then changing its orbit so it

If you find any asteroid with a sufficient magnesium hydride (or any other useful substances that could help you terraform Venus), then changing its orbit so it goes and collides with Venus could be orders of magnitude simpler than building a space colony. In the asteroid belt there are some so-called Kirkwood gaps [1]. The main one is at 2.5 AU from the Sun; an asteroid orbiting at that distance is in a certain resonance with Jupiter (and with the Earth too) that makes the orbit unstable (on large time scales). The orbit becomes more and more eccentric, until it crosses Mars's orbit, and in time it gets close to Mars and gets sling-shot somewhere. There is a good chance you can nudge an asteroid close to this or another Kirkwood gap, and do it in such a way as to obtain the exact Mars slingshot that the asteroid ends up crashing into Venus. How can you nudge an asteroid? By ablation, e.g. [2]. You can use either a large parabolic mirror that orbits the asteroid, or a powerful laser. What timescales are we talking about? Asteroids in the Alinda group [3] have an orbital period of 4 years; if we manage to perturb one's orbit and execute the Martian slingshot in 10 periods, that's roughly half a century, which is in line with the mission length of Voyager. [1] https://en.wikipedia.org/wiki/Kirkwood_gap https://en.wikipedia.org/wiki/Kirkwood_gap [2] https://en.wikipedia.org/wiki/Asteroid_laser_ablation https://en.wikipedia.org/wiki/Asteroid_laser_ablation [3] https://en.wikipedia.org/wiki/Alinda_asteroid https://en.wikipedia.org/wiki/Alinda_asteroid