An experiment to test in-field pointing for Elisa
conference paper
The evolved Laser Interferometer Space Antenna (eLISA) Mission is being developed to detect and characterise gravitational waves by measuring pathlength changes between free flying inertial test masses over a baseline of order 1 Gm [1]. Here the observed astrophysical events and objects lie in a frequency range between 30 μHz and 1 Hz (the LISA measurement band, LMB). Within the eLISA Mission, orbital dynamics cause the shape of the constellation to change over a period of one year. As a result, the angle between the interferometer arms varies by a few degrees on an annual timescale and must be actively compensated for. Most studies looking at eLISA type missions typically feature the Telescope Pointing concept - articulating the two telescopes with a mechanism and adjusting the entire payload to compensate. One possible alternative concept which has been studied in the LISA Mission Formulation study carried out by Astrium Satellites Germany (now Airbus DS) is to utilise In-Field Pointing (IFP) [2]. With IFP, a small mechanism would tilt a mirror positioned at an intermediate pupil of a wide field telescope, thus providing the required pointing corrections. IFP possesses inherent advantages over Telescope Pointing in that it removes the need to articulate large parts of the payload, does not require a backlink fibre to connect adjacent arms, can result in smaller payload sizes and enables payload architectures with only one test mass per spacecraft. Demanding requirements are, however, placed on the optical properties of the telescope and the stability of the mechanism.
Topics
TNO Identifier
954820
ISSN
0277786X
ISBN
9781510616
Publisher
SPIE
Article nr.
2304152
Source title
International Conference on Space Optics, ICSO 2014, La Caletta, Tenerife, Spain, 7-10 October 2014
Editor(s)
Sodnik, Z.
Karafolas, N.
Cugny, B.
Karafolas, N.
Cugny, B.
Collation
8 p.
Files
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