# The distance, supernova rate and supernova progenitors of NGC 6946

## TL;DR

This study refines the distance to NGC 6946 using supernova rates and dust extinction methods, leading to improved understanding of supernova progenitors and recommending a new standard distance for future research.

## Contribution

The paper provides a new distance estimate for NGC 6946 based on supernova rate analysis and dust extinction, impacting progenitor studies and future observations.

## Key findings

- Distance to NGC 6946 is approximately 7.9 Mpc, larger than previously assumed.
- Revised distance improves consistency between observed progenitors and stellar models.
- Authors recommend using the updated distance of 7.72 Mpc for future studies.

## Abstract

The distance to the fireworks galaxy NGC 6946 is highly uncertain. Recent distance estimates using the tip of the red giant branch of 7.7 to 7.8 Mpc are larger than the distance commonly assumed for studying supernovae in this galaxy of 5.9 Mpc. Here we use the high supernova rate of the galaxy to derive the star-formation rate and predict the galaxy's FUV flux. We also account for dust extinction by different methods to derive a distance of 7.9+/-4.0 Mpc for NGC 6946. We then use the new distance to re-evaluate the understanding of the supernova progenitors 2002hh, 2004et, 2017eaw, the possible electron capture event 2008S and the possible black-hole forming event N6946-BH1. For the latter two exotic events the new distance improves the consistency between the observed progenitors and the stellar models that give rise to these events. From our findings we strongly recommend that all future studies of NGC~6946 must use the greater distance to the galaxy of 7.72+/-0.32 Mpc of Anand et al. (2018).