https://www.channelnewsasia.com/business/scientists-unveil-n...
> «The EHT is a very sparse array of telescopes. This is something we cannot do anything about because we need to put our telescopes on the tops of mountains and these mountains are few and far apart from each other [...] As a result, our telescope array has a lot of "holes" and we need to rely on algorithms that allow us to fill in the missing data»