If using the Sun as a lens is practical for us, it's likely to be practical for them. They can manage radio transmission, so it's a matter of time before they i

If using the Sun as a lens is practical for us, it's likely to be practical for them. They can manage radio transmission, so it's a matter of time before they image Earth as well : relativity, rocket science and electronics is not far off from radio transmissions in term of knowledge.