Proceedings Article | 1 July 1990
KEYWORDS: Telescopes, Extreme ultraviolet, Multilayers, Iron, Space telescopes, Solar processes, Image resolution, Mirrors, Astronomy, Aerospace engineering
We describe a space borne solar observatory, the Ultra High Resolution XUV Spectroheliograph (UHRXS),
which has been selected by NASA for flight among the initial scientific instruments to be placed on the space
station "Freedom". The principal URRXS instruments are nine XUV multilayer Ritchey-Chretien Telescopes
covering the spectral range from -70 to -350 A; each telescope is able to isolate line multiplets within a narrow
wavelength interval which are excited over a narrow temperature range, providing full disk images of diagnostic
quality covering structures in the solar atmosphere ranging in temperature from T .5O,OOO K (He II ). 304 A) to
20,000,000 K (Fe XXIV X 192 A). The XUV images will be recorded on high resolution 70 mm format film,
allowing resolutions as high as 0. 1 arc second to be achieved for a 1.O field. The XUV images will be supplemented
by; (i) full disk high resolution (O.1") far ultraviolet images in H I Ly a ( 1216 A) and C IV (X 1548/1550 A),
(ii) full disk soft x-ray images in 4 bands in the interval ?X 6 -70 A and (iii) electronically recorded high resolution
(;v&% >10,000) spectroheliograms in 2 XUV, 1 EUV (.'45O A to 1 100 A) and 2 FUV (-4 100 A to 1600 A) bands.
The electronically recorded images will use the Multi-Anode Multi-Channel Array (MAMA) detector. We propose to
utilize the resulting data sets to address fundamental problems related to the following solar phenomena: (i) the fine
structure of the solar chromosphere/corona interface, (ii) the structure, energetics and evolution of high temperature
coronal loops, (iii) the large scale structure and dynamics of the corona, including the solar wind interface, the
magnetic filed, and coronal mass ejections, and (iv) solar flares, especially the pre-flare state, the impulsive release of
energy, and the evolution of post-flare loops.
Subject Terms: solar atmosphere, corona, soft x-ray (XUV), extreme ultraviolet (EUV), far ultraviolet (FUV),
multilayer optics
