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See detailSun Earth Connection Coronal and Heliospheric Investigation (SECCHI)
Howard, R. A.; Moses, J. D.; Vourlidas, A. et al

in Space Science Reviews (2008), 136

The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) is a five telescope package, which has been developed for the Solar Terrestrial Relation Observatory (STEREO) mission by the Naval ... [more ▼]

The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) is a five telescope package, which has been developed for the Solar Terrestrial Relation Observatory (STEREO) mission by the Naval Research Laboratory (USA), the Lockheed Solar and Astrophysics Laboratory (USA), the Goddard Space Flight Center (USA), the University of Birmingham (UK), the Rutherford Appleton Laboratory (UK), the Max Planck Institute for Solar System Research (Germany), the Centre Spatiale de Leige (Belgium), the Institut d'Optique (France) and the Institut d'Astrophysique Spatiale (France). SECCHI comprises five telescopes, which together image the solar corona from the solar disk to beyond 1 AU. These telescopes are: an extreme ultraviolet imager (EUVI: 1 1.7 R[SUB]o[/SUB]), two traditional Lyot coronagraphs (COR1: 1.5 4 R[SUB]o[/SUB] and COR2: 2.5 15 R[SUB]o[/SUB]) and two new designs of heliospheric imagers (HI-1: 15 84 R[SUB]o[/SUB] and HI-2: 66 318 R[SUB]o[/SUB]). All the instruments use 2048×2048 pixel CCD arrays in a backside-in mode. The EUVI backside surface has been specially processed for EUV sensitivity, while the others have an anti-reflection coating applied. A multi-tasking operating system, running on a PowerPC CPU, receives commands from the spacecraft, controls the instrument operations, acquires the images and compresses them for downlink through the main science channel (at compression factors typically up to 20×) and also through a low bandwidth channel to be used for space weather forecasting (at compression factors up to 200×). An image compression factor of about 10× enable the collection of images at the rate of about one every 2 3 minutes. Identical instruments, except for different sizes of occulters, are included on the STEREO-A and STEREO-B spacecraft. [less ▲]

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See detailDiscovery of the atomic iron tail of comet McNaught using the Heliospheric Imager on STEREO
Fulle, M.; Leblanc, F.; Harrison, R. A. et al

in Astrophysical Journal (2007), 661(1, Part 2), 93-96

In 2007 January, at the heliocentric distance r < 0.3 AU, comet McNaught 2006P1 became the brightest comet since C/Ikeya-Seki 1965S1 and was continuously monitored by space-based solar observatories. We ... [more ▼]

In 2007 January, at the heliocentric distance r < 0.3 AU, comet McNaught 2006P1 became the brightest comet since C/Ikeya-Seki 1965S1 and was continuously monitored by space-based solar observatories. We provide strong evidence that an archlike tail observed by the Heliospheric Imager aboard the STEREO spacecraft is the first ever detected tail composed of neutral Fe atoms. We obtain an Fe lifetime tau = (4.1 +/- 0.4) x 10(4) s at r = 0.25 AU, in agreement with theoretical predictions of the photoionization lifetime. The expected dust temperature is inconsistent with iron sublimation, suggesting that Fe atoms are coming from troilite evaporation. [less ▲]

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See detailMAGRITTE / SPECTRE : the Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory
Rochus, Pierre ULg; Defise, Jean-Marc ULg; Halain, Jean-Philippe ULg et al

in AGU Fall Meeting Abstracts (2002), 21

The Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory will characterize the dynamical evolution of the solar plasma from the chromosphere to the corona, and will follow the ... [more ▼]

The Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory will characterize the dynamical evolution of the solar plasma from the chromosphere to the corona, and will follow the connection of plasma dynamics with magnetic activity throughout the solar atmosphere. The AIA consists of 7 high resolution imaging telescopes in the following spectral bandpasses: 1215 \x8F Ly-a, 304 \x8F He II, 629 \x8F OV, 465 \x8F Ne VII, 195 \x8F Fe XII (includes Fe XXIV), 284 \x8F Fe XV, and 335 \x8F Fe XVI. The telescopes are grouped by instrumental approach: the Magritte Filtergraphs (R. Magritte, famous 20th Century Belgian Surrealistic Artist), five multilayer EUV channels with bandpasses ranging from 195 to 1216 \x8F, and the SPECTRE Spectroheliograph with one soft-EUV channel at OV 629 \x8F. They will be simultaneously operated with a 10-second imaging cadence. These two instruments, the electronic boxes and two redundant Guide Telescopes (GT) constitute the AIA suite. They will be mounted and coaligned on a dedicated common optical bench. The GTs will provide pointing jitter information to the whole SHARPP assembly. This poster presents the selected technologies, the different challenges, the trade-offs to be made in phase A, and the model philosophy. From a scientific viewpoint, the unique combination high temporal and spatial resolutions with the simultaneous multi-channel capability will allow Magritte/SPECTRE to explore new domains in the dynamics of the solar atmosphere, in particular the fast small-scale phenomena. We show how the spectral channels of the different instruments were derived to fulfill the AIA scientific objectives, and we outline how this imager array will address key science issues, like the transition region and coronal waves or flare precursors, in coordination with other SDO experiments. We finally describe the real-time solar monitoring products that will be made available for space-weather forecasting applications. [less ▲]

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