Sunrise (telescope)
# Sunrise (telescope)

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.

## Overview

The strong absorption of UV radiation by the Earth's atmosphere makes it challenging to carry out ground-based observations at these wavelengths. A balloon mission reaching altitudes of above 30 km benefits from a reduction of UV absorption by 99%, making engineering solutions for the telescope easier. The launch site was in the arctic region to make uninterrupted observation of the Sun over several days possible. The telescope has a 1 metre primary mirror that directs the 1 kW of solar radiation to the first focal point where 99% of the radiation is reflected out of the telescope, the remaining light is transferred into several instruments.

The one metre diameter primary mirror is made from a glass ceramic zerodur, it is the central part of the gondola of nearly 2 tons. Solar panels of 1.5 kW output power are used to power the onboard equipment and a hard disk array of 2 x 2.4 Terabyte is used to store the data during flight.

## Instruments

* CWS, Correlating Wavefront Sensor is a CCD camera with 1 kHz read-outs responsible generate the images necessary for image stabilization and proper alignment.
* SUFI, Sunrise Filter Imager observes the sun in five distinct wavelengths 214, 300, 312, 388 and 397 nm, on a 2048 x 2048 pixel CCD, through a filter wheele.
* IMaX, Imaging Magnetograph eXperiment observes the Zeeman splitting of the iron line (FeI) around 525 nm. The observed field of view is 50 x 50 arcseconds.

## Flights

* Sunrise's first flight was launched at 8:05 8 June 2009 local time from Esrange, near Kiruna, Sweden and it landed 1:45 14 June 2009 local time on Somerset Island, Nunavut, northern Canada after a flight duration nearly six days.
* Sunrise's second flight was launched at 7:38 (5:38 UTC) on 12 June 2013 from Esrange, near Kiruna, Sweden, and it landed afternoon 17 June 2013 on Boothia peninsula, Nunavut, northern Canada after a flight duration of over 5 days.
* Sunrise's third flight is scheduled for July 2022 from Esrange, near Kiruna, Sweden,. The third edition of sunrise is a step forward in terms of onboard instrumentation, with three new instruments, SUSI, SCIP, and TuMAG.
