Expansion Parallax for the Compact Planetary Nebula M2-43

TL;DR

This study uses radio observations over 4 years to measure the expansion of planetary nebula M2-43, deriving its distance with high precision, the largest achieved with this method.

Contribution

It presents the first expansion parallax measurement for M2-43, demonstrating the technique's effectiveness for distant planetary nebulae.

Findings

Measured expansion rate of 0.61 mas/year

Derived a distance of 6.9 kpc to M2-43

Established the largest distance for a planetary nebula via this method

Abstract

We present high quality radio continuum observations made with the Very Large Array (VLA) at 3.6 cm at two epochs toward the planetary nebula M2-43. The comparison of the two epochs, obtained with a time separation of 4.07 years, clearly shows the expansion of the planetary nebula with an angular rate of 0.61 +/- 0.09 mas/year.Assuming that the expansion velocity in the plane of the sky (determined from these measurements) and the expansion velocity in the line of sight (determined from optical spectroscopy available in the literature) are equal, we find a distance to the planetary nebula of 6.9 +/- 1.5 kpc. This is the largest distance for a planetary nebula measured up to now with this technique.