SST – Space Solar TelescopeSST – Space Solar Telescope

SatelliteSatellite

Solar synchronous circular orbit

Orbit height: 735 km

Inclination: 98.3°Period: 99.3 min

Attitude: accuracy ±6", stability ±3"/s

Weight: 2 ton

Duration: 3 years

Launch: LM-4B

PayloadPayload MOT: with a 2-D polarizing spectrograph for

simultaneously working in 8 channels EUT: viewing the solar corona and transition

region at various temperatures HWT: whole sun viewing WBS: investigating high energy flare

process SIR: nonthermal electron populations

MOT 0.1 2.8'×1.5' 8 channels

2×10 -4

EUT 0.5 8.5'×8.5' 4 channels

HWT 1 0.7°×0.7°

WBS -ray, hard x-ray, soft x-ray

SIR 1-60 MHZ

Correlation Tracker Correlation Tracker

Sensitivity 0.01

Time constant <1 ms

Tracking accuracy ± 0.015 Control rang ± 7.5´

Close-loop bandwidth 100 Hz

CT testCT test horizontal 10Hz， vertical 11Hz, amplitude ±6 pixels

Loop closed Loop opened

CT open loop CT close loop

On Board Data ProcessingOn Board Data Processing

PP

MM

DSP DSP

CEU

OBDH

DL

EUT EUT (Phase A requirements)(Phase A requirements)

Based on the EUVSAT proposal. Consists of a bundle of four normal incidence telescopes mounted in a vacuum vessel, which should overlap, be well aligned and synchronized with each other and with the images of the MOT.

Field of view 8.5’×8.5’

Pixel resolution 0.25”

Format 2048 2048

Wave length 12.8 17.1 19.5 30.4 nm

(subject to change)

DetectorDetector

A CCD imager is to be used with format

changing optics (fiber optic taper) in front of it. In order to achieve high sensitivity, an image

intensifier is proposed. A front phosphor screen is needed to

converse EUV photons to visibles.

Camera Configuration

The proposal of CIOM The proposal of CIOM

Wave length 17.1nm

FOV 8.58.5Pixel resolution 0.4(0.25)

Focal length 7.4 m

Distance between Mirrors 1.817 m

From PM to FP >0.1 m

Primary Mirror 120 mm

Secondary mirror 48 mm

Camera system RequirementsCamera system Requirements1. Inputs: EUV image pixel & Format:

9m× 9m (0.25), 2048 ×2048 Wavelengths &

EUV Photon flux per pixel per second:

(TBC)Wavelengths 12.8 17.1 19.5 30.4

Photon flux 7.3810-

4(quiet)

>710 (flare)

125 80 189

Camera system RequirementsCamera system Requirements

2. Radiometric performances: Dynamic range & linearity:

>2500, 0.5% in full range 12-bits digitization SNR: >250

Camera system RequirementsCamera system Requirements

3. Temporal Resolution: < 2 sec.

4. Dimensions and Weights Overall size:

<100mm×150mm Total Weight:

<2.5Kg/each Camera set

Camera system RequirementsCamera system Requirements

5. Power supply: 25~30v input , <10 watt/each camera set6. Operational Environments Radiational: ToT: 20Krad(Si) SEU/L: TBD Thermal: -20ºC~+50ºC, passive cooler for CCDs EMC: TBD Vibration, Shock, etc.

Front illuminated CCD, size 2048×2048 pixels.

Pixel size on CCD 14 m × 14 m, resulting in 28.6mm × 28.6mm image size.

CCD operated in full-frame mode. Readout simultaneously through 2

channels; failure mode with readout through the remaining functional channel.

CCD operated in MPP mode, with low dark charge and noise.

Correlated double sampling (CDS) with digitizing by 12 bit ADCs.

Camera System pecificationsCamera System pecifications

Main Difficulties on EUT Main Difficulties on EUT instrumentationinstrumentation

Resolution: the optics and the detector

Test on observation wavelength.

EUT Financing EUT Financing

Before 2003 0.8M RMB NAOC

2003 2.0M RMB NSFC

2004 2.0M RMB NAOC

NATIONAL ASTRONOMICAL NATIONAL ASTRONOMICAL

OBSERVATORYOBSERVATORY