National Aeronautics and Space Administration

Spacecraft & Instruments

The IRIS instrument is a multi-channel imaging spectrograph with a 20 cm UV telescope. IRIS will obtain spectra along a slit (1/3 arcsec wide), and slit-jaw images. The CCD detectors will have 1/6 arcsec pixels. IRIS will have an effective spatial resolution between 0.33 and 0.4 arcsec and a maximum field of view of 120 arcsec.

The far-UV channel covers:

• 1332-1358 Å and 1390-1406 Å with 40 m Å resolution and an effective area of 2.8 cm².

The near-UV channel covers:

• 2785-2835 Å with 80 mÅ resolution and an effective area 0.3 cm².

Slit-jaw imaging will have four passbands:

• 1335 Å and 1400 Å with 40 Å bandpass each
• 2796 Å and 2831 Å with 4 Å bandpass each

IRIS will have a high data rate (0.7 Mbit/s on average) so that the baseline cadence is: 5s for slit-jaw images, 1s for 6 spectral windows, including rapid rastering to map solar regions.

IRIS Observatory Overview

Spectrograph Assembly