By Iseman’s own description, the first two balloon launches were very rudimentary. He says they occurred in April somewhere in the Baja peninsula, months before Make Sunsets was incorporated in October. Iseman says he pumped a few grams of sulfur dioxide into weather balloons and added what he estimated would be the right amount of helium to carry them into the stratosphere. 

He expected they would burst under pressure at that altitude and release the particles. But it’s not clear whether that happened, where the balloons ended up, or what impact the particles had, because there was no monitoring equipment on board the balloons. Iseman also acknowledges that they did not seek any approvals from government authorities or scientific agencies, in Mexico or elsewhere, before the first two launches. 

MIT Technology Review