In this composite image taken by Juno's Stellar Reference Unit, the arrows point to small lightning flashes observed on Jupiter's cloud tops; the magnified insets show how they appeared in the science imager. The small size is evidence that the lighting is shallow, originating at unexpectedly high altitudes where it is too cold for liquid water to exist. Designed to detect dim stars, the Stellar Reference Unit's optics enable identification of tiny points of light. The data for this composite was taken by the Stellar Reference Unit on Feb. 7, 2018.
The solar-powered Jupiter explorer launched on Aug. 5, 2011 and went into orbit around the gas giant on July 4, 2016.
More information about Juno is at http://www.nasa.gov/juno and http://missionjuno.swri.edu.