Vision of microarcsecond optical imaging: expected resolution for an assumed transit of a hypothetical exoplanet across the disk of Sirius. Stellar diameter =1.7 solar; distance =2.6 pc; angular diameter =6 mas; assumed planet of Jupiter size and oblateness; equatorial diameter =350 μas; Saturn-type rings; four Earth-size moons. With a Cherenkov telescope array spanning 2 km, already a 50 μas resolution provides more than 100 pixels across the stellar diameter.