Future Prospects: Deep Imaging of Galaxy Outskirts using Telescopes Large and Small

TL;DR

This paper discusses recent technical advances and observations in low surface brightness imaging of galaxy outskirts, highlighting the potential for new discoveries with innovative telescopes like Dragonfly.

Contribution

It introduces the Dragonfly Telephoto Array and its role in advancing low surface brightness imaging of the Universe.

Findings

Dragonfly has achieved unprecedented low surface brightness imaging.

Recent technical solutions have begun to overcome longstanding observational barriers.

New discoveries suggest much more remains to be explored at low surface brightness levels.

Abstract

The Universe is almost totally unexplored at low surface brightness levels. In spite of great progress in the construction of large telescopes and improvements in the sensitivity of detectors, the limiting surface brightness of imaging observations has remained static for about forty years. Recent technical advances have at last begun to erode the barriers preventing progress. In this Chapter we describe the technical challenges to low surface brightness imaging, describe some solutions, and highlight some relevant observations that have been undertaken recently with both large and small telescopes. Our main focus will be on discoveries made with the Dragonfly Telephoto Array (Dragonfly), which is a new telescope concept designed to probe the Universe down to hitherto unprecedented low surface brightness levels. We conclude by arguing that these discoveries are probably only scratching the surface of interesting phenomena that are observable when the Universe is explored at low surface brightness levels.