Vy 1-2 is a planetary nebula discovered by Russian-American astronomer Alexander N. Vyssotsky in 1942.
General information Vy 1-2 contains a faint outer shell and two much fainter knots at a position angle (PA) of 305°. The south knot is located 14.5 arcsec from the central star while the north knot is located 11.5 arcsec form the central star. The knots deprojected radial expansion velocity is 90–100 km s⁻¹, and their kinematic age is 5200 ± 750 yr for a distance = 9.7 kpc. Vy 1-2 also has a bright-elliptical ring like structure with a minor axis of 2.4 arcsec and a major axis of 3.2 arcsec. The distance of Vy 2-1 remains uncertain, with estimates ranging from 7.0 to 14.5 kpc,<ref name = "dist" this was calculated using a mean radius of ~1.4 arcsec. The systemic heliocentric radial velocity of the nebula is Vsys = -85 ± 4 km s⁻¹. Vy 1-2 has been a candidate for a halo PN because of its high systemic velocity (~500 pc) from the galactic plane.
The zanstra temperature of the He I line is 75.4 ± 10.2kK while the He II line is 99.8 ±4.3kK. The logarithmic Hβ flux is estimated to be -11.52 ± 0.01.
Central star The central star is unknown, possibly a WR or a strong and fast WEL nucleus, with the detection of C II, C IV, and O III stellar lines supports the scenario. Anonther scenario used to prove a anomaly in BD +30° 3639" suggests the central star is a binary system.
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