This is terribly incorrect. Space is not a solution. The amount of energy required to send trash into space is very high and therefore expensive, like ~$5000/kg, and would generate a stupid amount of C02. Watch this video, it gives a great perspective on the scope of the problem: https://www.youtube.com/watch?v=Us2Z-WC9rao

Alternatively, the Earth is HUGE. All the garbage ever generated in the history of humankind would fit into a comparatively tiny space. This is obviously a terrible option too, but WAY better than space.

Burning it is also terrible - no matter how good we get the incinerators, they still produce unacceptable levels of dioxins and other chemicals. You are much more likely to get cancer if you live near an incinerator.

The ONLY solution is to stop producing so much plastic.