Science news, night sky events and beautiful photos, all in one place. Click here to subscribe to EarthSky\u2019s free daily newsletter.<\/strong><\/p>\n By the late 1980s, astronomers suspected that there are rings around Neptune, our solar system\u2019s outermost major planet. After all, the next planet inward, Uranus, has rings (found in 1977). So does Jupiter (found in 1979) and Saturn (first glimpsed through early telescopes in the 1600s).<\/p>\n Then, watching from Earth in 1984, astronomers recorded extra blinks before and after Neptune passed in front of a distant star. That added to the evidence that Neptune had at least a partial ring system. But it was NASA\u2019s Voyager 2 spacecraft that provided the first photographic proof of the existence of Neptune\u2019s rings on August 22, 1989. <\/p>\n At the time, the spacecraft was a few days out from its closest encounter with the planet on August 25, 1989. As Neptune began looming large in Voyager\u2019s cameras, the spacecraft photographed a faint but continuous ring system encircling the planet. The images of Neptune\u2019s rings confirmed astronomers\u2019 long-held suspicions. <\/p>\n Today, Voyager 2 remains the only earthly spacecraft to have encountered Neptune. But since Voyager\u2019s 1989 flyby, the Hubble Space Telescope, the James Webb Space Telescope, and Earth-based telescopes have imaged the two brightest rings of Neptune. Astronomers named those two Neptunian rings Adams<\/em> and Le Verrier<\/em>. They\u2019re named for John Couch Adams and Urbain Jean Joseph Le Verrier, whose independent calculations helped find Neptune\u2019s position in the sky \u2013 and thus led to its discovery \u2013 in 1846. <\/p>\n There are also three more rings around Neptune: Galle, Lassell, Arago. So moving outward from near the planet, the main rings are Galle, Leverrier, Lassell, Arago, and Adams.<\/p>\n Today, we know that Neptune has at least five main rings. Plus, it has four prominent ring arcs. The arcs are peculiar clumps of dust. Astronomers struggled to understand their existence, because the laws of motion predict these arcs should spread out into a uniform ring over short timescales. Scientists now believe the gravitational effects of Galatea, a moon just inward from the ring, confine the arcs. <\/p>\n Also, four of the prominent arcs have names. Astronomers call them Libert\u00e9 (Liberty), Egalit\u00e9 (Equality), Fraternit\u00e9 (Fraternity), and Courage. They\u2019re located in the outermost ring, Adams. <\/p>\n Bottom line: NASA\u2019s Voyager 2 spacecraft confirmed the discovery of Neptune\u2019s rings on August 22, 1989, when it took images of a faint, continuous ring system around the planet.<\/p>\n Read more: Webb sees Neptune\u2019s rings and moons<\/p>\n <\/div>\nNeptune\u2019s rings confirmed August 22, 1989<\/h3>\n
Names for Neptunian rings<\/h3>\n
Peculiar ring arcs<\/h3>\n
![\"Several](\"https:\/\/earthsky.org\/upl\/2014\/08\/Rings-of-Neptune-NASAJPL-Aug-26-1989.jpg\")