SH2-216

Title: SH2-216

Date image was taken: February 20, 2026

Location: Trevinca Skies Spain

Data Acquisition Method: Personal Telescope Setup

Description and Details: Sh2-216 is a planetary nebula visible in the constellation of Perseus.

It is located in the easternmost part of the constellation, about 5° west of the bright Capella. It appears as a tenuous gaseous filament difficult to observe because of its low light. Its observation requires powerful and sensitive tools and in long-exposure photos, it barely emerges from the star field in the background. Its declination is moderately northern, so its observation is considerably facilitated for observers placed at the boreal latitudes. To the south of the equator, on the other hand, it can only easily be seen up to the lower temperate regions.

With a distance of only 420 light-years, it is the planetary nebula closest to the solar system. The great dispersion of its gases, which also makes it the greatest observable planetary nebula in the celestial vault, is due to the great age of the cloud, estimated at about 600 000 years. It was initially catalogued as an H II region, although the star responsible for gas ionization was not identified. Later, thanks to spectrometric studies, the hypothesis was advanced that the cloud could be the rest of an ancient planetary nebula with an extremely low rate of expansion[, a hypothesis confirmed later thanks to the discovery of the central star, a white dwarf cataloged like LSV+46°21. The surface temperature of the white dwarf is between 50 000 and 90 000 Kelvin.
Materials :
ASKAR FRA500 Bezel
Camera Altair Hypercam 26M
Filters Antlia 3nm
Gemini G53F Mount @ Onstep

HA : 231 x 300s (19H15)
O3 : 152 x 300s (12H40)
Total integration : 31H55

Remote Trevinca Skies Spain

copyright: frederic lamagat