We present an overview of solar sounding rocket instruments developed jointly by NASA Marshall Space Flight Center
and the University of Alabama in Huntsville. The High Resolution Coronal Imager (Hi-C) is an EUV (19.3 nm) imaging
telescope which was flown successfully in July 2012. The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) is a
Lyman Alpha (121.6 nm) spectropolarimeter developed jointly with the National Astronomical Observatory of Japan and
scheduled for launch in 2015. The Marshall Grazing Incidence X-ray Spectrograph is a soft X-ray (0.5-1.2 keV) stigmatic
spectrograph designed to achieve 5 arcsecond spatial resolution along the slit.
The NASA Interface Region Imaging Spectrograph (IRIS) mission is a Small Explorer (SMEX) satellite mission
designed to study plasma dynamics in the “interface region” between the Sun’s chromosphere and corona with high
spatial, spectral, and temporal resolution. The primary instrument is a dual Czerny-Turner spectrograph fed by a 20-cm
Cassegrain telescope measuring near- and far-ultraviolet (NUV, FUV) spectral lines in the ranges 133-141 nm and 278-
283 nm. To determine the position of the slit on the solar disk, a slit-jaw imaging system is used. The NUV slit-jaw
imaging system produces high spatial resolution images at two positions in the Mg II 280 nm spectral line complex using
a birefringent Solc filter with two wide-band interference pre-filters for spectral order selection. The Solc filter produces
a 0.36 nm full-width at half-maximum (FWHM) filter profile with low sidelobes and a peak transmission of 15% at
279.6 nm. The filter consists of two “wire grid’’ polarizers surrounding 8 quartz waveplates configured in a modified
Solc “fan” rotational pattern. The elements are optically coupled using DC200 silicon-based grease. The NUV Solc filter
is sealed in a windowed cell to prevent silicon contamination of the FUV channel. The design of the sealed cell and
assembly of the filter into the cell were among the most challenging optomechanical aspects of the IRIS spectrograph
This paper discusses the design of the IRIS Small Explorer (SMEX) Cassegrain telescope, as well as its intended and measured
performance. Lockheed Martin, along with SAO, Montana State University, and Stanford University are developing
the IRIS instrument for a mission to examine the solar spectra in two bands, one centered on 1369 Å, and the other centered
on 2810 Å. SAO led the design and construction of the telescope feed, with assistance from Lockheed and Montana State
The telescope posed a number of implementation challenges, which are discussed here, including the fact that no effective
filters exist to isolate the science spectra to the exclusion of the rest of the solar flux, making it necessary to allow full
sunlight into the telescope.
The Interface Region Imaging Spectrograph (IRIS) is a NASA SMall EXplorer mission scheduled for launch in January
2013. The primary goal of IRIS is to understand how the solar atmosphere is energized. The IRIS investigation
combines advanced numerical modeling with a high resolution UV imaging spectrograph. IRIS will obtain UV spectra
and images with high resolution in space (0.4 arcsec) and time (1s) focused on the chromosphere and transition region of
the Sun, a complex interface region between the photosphere and corona. The IRIS instrument uses a Cassegrain
telescope to feed a dual spectrograph and slit-jaw imager that operate in the 133-141 nm and 278-283 nm ranges. This
paper describes the instrument with emphasis on the imaging spectrograph, and presents an initial performance
assessment from ground test results.
This paper describes the flight control software of the wave-front correction system that flew on the 2009 science
flight of the Sunrise balloon telescope. The software discussed here allowed fully automated operations of the
wave-front sensor, communications with the adaptive optics sub-system, the pointing system, the instrument
control unit and the main telescope controller. The software was developed using modern object oriented
analysis and design techniques, and consists of roughly 13.000 lines of C++ code not counting code written for
the on-board communication layer. The software operated error free during the 5.5 day flight.
The High-resolution Lightweight Telescope for the EUV (HiLiTE) is a Cassegrain telescope that will be made entirely of
Silicon Carbide (SiC), optical substrates and metering structure alike. Using multilayer coatings, this instrument will be
tuned to operate at the 465 Å Ne VII emission line, formed in solar transition region plasma at ~500,000 K. HiLiTE will
have an aperture of 30 cm, angular resolution of ~0.2 arc seconds and operate at a cadence of ~5 seconds or less, having
a mass that is about 1/4 that of one of the 20 cm aperture telescopes on the Atmospheric Imaging Assembly (AIA)
instrument aboard NASA's Solar Dynamics Observatory (SDO). This new instrument technology thus serves as a path
finder to a post-AIA, Explorer-class missions.
SUNRISE is an international project for the development, construction, and operation of a balloon-borne solar telescope with an aperture of 1 m, working in the UV/VIS spectral domain. The main scientific goal of SUNRISE is to understand the structure and dynamics of the magnetic field in the atmosphere of the Sun. SUNRISE will provide near diffraction-limited images of the photosphere and chromosphere with an unpredecented resolution down to 35 km on the solar surface at wavelengths around 220 nm. The focal-plane instrumentation consists of a polarization sensitive spectrograph, a Fabry-Perot filter magnetograph, and a phase-diverse filter imager working in the near UV. The first stratospheric long-duration balloon flight of SUNRISE is planned in Summer 2009 from the swedish ESRANGE station. SUNRISE is a joint project of the german Max-Planck-Institut fur Sonnensystemforschung (MPS), Katlenburg-Lindau, with the Kiepenheuer-Institut fur Sonnenphysik (KIS), Freiburg, Germany, the High-Altitude Observatory (HAO), Boulder, USA, the Lockheed-Martin Solar and Astrophysics Lab. (LMSAL), Palo Alto, USA, and the spanish IMaX consortium. In this paper we will present an actual update on the mission and give a brief description of its scientific and technological aspects.
SUNRISE is a balloon-borne solar telescope with an aperture of 1m, working in the UV/VIS optical domain. The main scientific goal of SUNRISE is to understand the structure and dynamics of the magnetic field in the atmosphere of the Sun. SUNRISE will provide diffraction-limited images of the photosphere and chromosphere with an unpredecented resolution down to 35km at wavelengths around 220nm. Focal-plane instruments are a spectrograph/polarimeter, a Fabry-Perot filter magnetograph, and a filter imager. The first stratospheric long-duration balloon flight of SUNRISE over Antarctica is planned in winter 2006/2007. SUNRISE is a joint project of the Max-Planck-Institut fur Sonnensystemforschung (MPS), Katlenburg-Lindau, with the
Kiepenheuer-Institut für Sonnenphysik (KIS), Freiburg, the High-Altitude Observatory (HAO), Boulder, the Lockheed-Martin Solar
and Astrophysics Lab. (LMSAL), Palo Alto, and the Instituto de Astrofisica de Canarias, La Laguna, Tenerife.
In this paper we will present an overview on the mission and give a
description of the instrumentation, now, at the beginning of the
hardware construction phase.
Sunrise is a light-weight solar telescope with a 1 m aperture for spectro-polarimetric observations of the solar atmosphere. The telescope is planned to be operated during a series of long-duration balloon flights in order to obtain time series of spectra and images at the diffraction-limit and to study the UV spectral region down to ~200 nm, which is not accessible from the ground.
The central aim of Sunrise is to understand the structure and dynamics of the magnetic field in the solar atmosphere. Through its interaction with the convective flow field, the magnetic field in the solar photosphere develops intense field concentrations on scales below 100 km, which are crucial for the dynamics and energetics of the whole solar atmosphere. In addition, Sunrise aims to provide information on the structure and dynamics of the solar chromosphere and on the physics of solar irradiance changes.
Sunrise is a joint project of the Max-Planck-Institut fuer Aeronomie (MPAe), Katlenburg-Lindau, with the Kiepenheuer-Institut fuer Sonnenphysik (KIS), Freiburg, the High-Altitude Observatory (HAO), Boulder, the Lockheed-Martin Solar and Astrophysics Lab. (LMSAL), Palo Alto, and the Instituto de Astrofi sica de Canarias, La Laguna, Tenerife. In addition, there are close contacts with associated scientists from a variety of institutes.
As a Japanese National space mission with international collaboration, Solar-B (2005 launch) will carry a spectro- polarimeter (SP) to be operated in visible light to obtain the first high angular resolution, precision measurements of solar vector magnetic fields from space. The SP is part of the Focal Plane Package (FPP) fed by a diffraction-limited 50-cm optical telescope. The SP will be operated exclusively at the photospheric 630 nm Fe I lines. It features a rotating, low-order crystalline quartz retarder for polarization modulation and a reflecting Littrow spectrograph design that is shortened by using diffraction from the 12micrometers wide slit to fill the grating. Polarization analysis is accomplished by a modified Savart plate beam splitter. A custom CCD detector with two active areas, one for each beam from the beam splitter, allows continuous high duty-cycle sampling of polarization. The spectrograph slit will sample a 0.16 x 164 arcsec2 rectangle of the solar image, which may be scanned across the slit by up to +/- 160 arcsec in order to build up vector magnetic field maps of the solar photosphere. Along with simultaneous, co-spatial imaging and polarimetry with the filter imagers of the FPP, the SP will provide a precise view of active and quiet solar magnetic fields that control the structure, dynamics, and energetics of the upper solar atmosphere.
The Transition Region and Coronal Explorer instrument (TRACE) will use narrow-band interference filters together with other appropriate band limiting elements to make high resolution images of the Sun in the C IV lines at 154.8 and 155.0 nm. Filter observations of solar C IV emission are complicated by the presence of UV Continuum and nearby chromospheric lines because of the relatively wide bandpasses of the narrowest currently available interference filters. TRACE will use a series of filters to estimate the effects of the UV continuum and the long-wavelength `leaks' in the blocking filters which we show are the most important contaminants in the C IV images. Further improvements in filtergraph performance may be realized through the use of tunable Fabry-Perot etalons, which have been under development at Lockheed-Martin. We present test data from a cultured quartz etalon designed for 155 nm, and will discuss the prospects for etalons operation at substantially shorter wavelengths.