Sunrise: instrument, mission, data and first results

TL;DR

The Sunrise observatory's first science flight provided high-resolution solar data revealing detailed convection, oscillations, and magnetic fields, including new insights into granulation and magnetic flux dynamics at around 100 km resolution.

Contribution

This paper presents the first results from Sunrise, a balloon-borne solar observatory, demonstrating its capability to observe solar features at unprecedented resolution and revealing new details of solar magnetic fields.

Findings

Clear observation of granulation at 214 nm.

Detection of highly dynamic, small-scale internetwork magnetic fields.

Increase in magnetic flux detection after polarization map reconstruction.

Abstract

The Sunrise balloon-borne solar observatory consists of a 1m aperture Gregory telescope, a UV filter imager, an imaging vector polarimeter, an image stabilization system and further infrastructure. The first science flight of Sunrise yielded high-quality data that reveal the structure, dynamics and evolution of solar convection, oscillations and magnetic fields at a resolution of around 100 km in the quiet Sun. After a brief description of instruments and data, first qualitative results are presented. In contrast to earlier observations, we clearly see granulation at 214 nm. Images in Ca II H display narrow, short-lived dark intergranular lanes between the bright edges of granules. The very small-scale, mixed-polarity internetwork fields are found to be highly dynamic. A significant increase in detectable magnetic flux is found after phase-diversity-related reconstruction of polarization maps, indicating that the polarities are mixed right down to the spatial resolution limit, and probably beyond.