The current state of speckle imaging

Speckle imaging produces diffraction-limited images from ground-based telescopes. Recent advancements in detectors such as electron-multiplying CCDs (EMCCDs), have spawned a resurgence of this technique, greatly improving sensitivity and observing efficiency. The high angular resolution provided by speckle imaging can discern blended binary system contamination and validate suspected exoplanets discovered by the Kepler and K2 transit surveys. High-resolution follow-up will also be required for upcoming missions including TESS. Multiplicity can be determined along with separation, position angle, photometry, and contrast ratio. In this way, speckle imaging can validate even small, rocky planets like TRAPPIST-1 and constrain exoplanet radii and density. Some of the developments leading to this technique will be discussed in conjunction with recent significant papers, ongoing speckle imaging programs, and prospects for the future.