Technical description

Odin is equipped with a high precision offset Gregorian telescope of diameter 1.1 m, followed by four tuneable, SSB sub-millimetre wave Schottky mixers and a fixed-tuned HEMT receiver at 119 GHz. Any four, three, or two (depending upon the satellite power available) of these front-end receivers can be combined with any of three spectrometers (a broad band acousto-optical spectrometer, AOS, and two flexible hybrid auto-correlators, AC1 & 2). Some salient features of the Odin satellite observatory are summarised in the table below. Based upon Jupiter observations, the main beam efficiency of the telescope has been determined to be as high as 90% at 557 GHz , the frequency of the water line. The rather complex radio receiver system was integrated, tested and optimised by engineers in the Onsala Space Observatory receiver laboratory. For aeronomy purposes, Odin is equipped with an Optical Spectrograph and InfraRed Imaging System, OSIRIS, developed in Canada.

The satellite:

Platform:   ​ 3-axis stabilized (reaction wheels, star sensors, gyros)​
Mass:​ 250 kg (platform 170 kg, science equipment 80 kg)​
Size:​ Height 2 m, width 3.8 m (including solar panels)​
Orbit: circular sunsynchronous polar orbit, altitude 600 km​

The science equipment (mm and sub-mm waves):

Antenna size:​ 1.1 m    ​
Beam size at 119/550 GHz:​ 9.5'/ 2.1'(126")​
Main beam efficiency:​ 90%​
Pointing uncertainty:​ <10" (rms)​
Submm tuning range:​ 486–504, 541–581 GHz   ​
Submm noise temperature:​ 3300 K (SSB)​
HEMT centre frequency:​ 118.75 GHz​
2.5 mm noise temperature:​ 600 K (SSB)​
AOS bandwidth & resolution:​ 1100 MHz / 1 MHz​
AC1 & 2 bandwidth & resolution:​ 100–800 MHz / 0.25–2 MHz   ​
 

Published: Wed 04 Sep 2013. Modified: Thu 16 Oct 2014