Kohoutek 1-16 (K 1-16, PK 94 + 27.1, PN G094.0 + 27.4)

Kohoutek 1-16 (K 1-16, PK 94 + 27.1, PN G094.0 + 27.4) is a planetary nebula in the constellation Draco. Distance to K 1-16 is estimated at 7000 light years. The apparent size of the nebula is 130"x100" and the integral magnitude is about 14.6m. The blueish star in the center is the associated white dwarf (WD 1821+643). High-speed photometry of the central star of the planetary nebula Kohoutek 1-16 shows it to be a low-amplitude pulsating variable. The dominant period is 28.3 minutes, with a semiamplitude that is usually about 0.01 mag. Below and slightly to the left of K 1-16 (near the nebula itself), a bluish star-shaped object is visible. This is the quasar KUV 18217+6419, one of the brightest objects of this type in the sky. This stellar object was discovered in 1977 as an X-ray source by the HEAO1 satellite (H). With the same property it was observed again in 1980 by the Einstein satellite (E) with higher precision. In 1981, a stellar object of v=14.1m was found as the optical counterpart. Follow-up spectroscopic investigations revealed a Seyfert 1-spectrum, which led to the quasar classification. Just one year earlier, this quasar was found independently in the optical (v=14.24 m) by the KISO-Survey (KUV), searching for UV-bright stellar sources. The distance to the quasar is about 3.4 billion light years. This image taken in August 2020.