This will cause a darkening or brightening of the image. This rapid brightening near opposition is called the opposition effect. The increase in pressure results in further brightening of the lamp. The climatic impacts of marine cloud brightening would be rapidly responsive and reversible. It has since been gradually brightening back to around +2.2. The modeling evidence of the global climatic effects of marine cloud brightening remains limited. Older comets show a more consistent brightening pattern. Yet another brightening in infrared occurred in early April. Later investigations found photographs showing the supernova brightening rapidly early on February 23rd. All of them utilize proprietary brightening agents. Whether marine cloud brightening itself could be such pollution of the marine environment is unclear. The costs of marine cloud brightening remain largely unknown. Pluto's visual apparent magnitude averages 15.1, brightening to 13.65 at perihelion. They discourage intruding males by brightening their red heads and doing "push-ups". The brightening is interpreted as the tidal disruption of an exoasteroid.