IMAGE FUV camera system
The Far-Ultra-Violet, FUV, instrument employs 3 detectors:
1. The Wideband Imaging Camera (WIC) to image the aurora, mainly produced by
electrons, in a broad band for maximum spatial resolution day and night.
2. The Spectrographic Imager (SI) to image aurora caused by electrons and
protons separately. SI has two channels: SI12 at 121.8 nm (i.e.,the
Doppler-shifted Lyman alpha and blocks out the bright 121.6 nm emission from
the geocorona) images only the proton aurora. SI13 (Oxygen line at 135.6 nm)
images electron and proton aurora.
WIC and SI image the whole Earth aurora from distances greater than 4 Re from
the center of the Earth.
Click on image to get larger picture.
3. Geocorona photometers (GEO) to observe the geocorona. The geocorona comes
from the cold neutral hydrogen surrounding the Earth, which is lightened up by
Solar Lyman alpha (121.6 nm). These measurements can be used to determine the
magnetospheric hydrogen content surrounding the Earth.
IMAGE is a spin stabilized satellite and rotates once in 120 s. This enables
the GEO photometers to perform a complete 360 degrees measurement during one
rotation but the imagers, WIC and SI, have to compensate the apparent motion
of the imaged Earth with the Time Delayed Imaging (TDI) technique
Characteristics of the FUV instruments:
* blocking out the 121.567 geocorna
|Channel||Spectral range||Field of view||Pixel||Spatial res.||Temporal res.||Sensitivity.
| ||(nm)||(degrees)||(#x#)||(deg. and km from apogee)||(s)||(R)
|WIC|| 140-180||17x17||256x256||0.1 - <100km|| 120||100
|SI12||121.82 *||15x15||128x128||0.15 - 100 km||120||100
|SI13||135.6||15x15 ||128x128 ||0.15 - 100 km||120 ||100
|GEO|| 121.6 ** ||1x1||1x1 ||-||0.33 ||-
** rejecting 130.4 nm
Learn more about the IMAGE FUV:
Mende et al.,Far ultraviolet imaging from the IMAGE spacecraft. 1. System design,
Space Sci. Rev.,91, 243-270, 2000.
Mende et al.,Far ultraviolet imaging from the IMAGE spacecraft. 2. Wideband FUV imaging,
Space Sci. Rev.,91, 271-285, 2000.
Mende et al.,Far ultraviolet imaging from the IMAGE spacecraft. 3. Spectral
imaging of Lyman-alpha and OI 135.6 nm, Space Sci. Rev.,91, 287-318, 2000.