18 Sagittarii is a single star in zodiac constellation of Sagittarius, located around 570 light years away from the Sun based on parallax. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.58. This object is moving closer to the Earth with a heliocentric radial velocity of −19 km/s.
This is an aging giant star with a stellar classification of K0 III, which indicates it has exhausted the hydrogen at its core and evolved away from the main sequence. It has expanded to about 29 times the Sun's radius and is radiating 309 times the Sun's luminosity from its enlarged photosphere at an effective temperature of . There is a much lower abundance of iron in the spectrum compared to the Sun.
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