Aluminum based large telescopes: the ARIEL Mission case

TY - CHAP

T1 - Aluminum based large telescopes

T2 - Space Telescopes and Instrumentation 2024: Optical, Infrared, and Millimeter Wave

AU - Picchi, P.

AU - Tozzi, A.

AU - Brucalassi, A.

AU - Araiza, Antonio J.

AU - Pace, E.

AU - Chioetto, P.

AU - Zuppella, P.

AU - Scippa, A.

AU - Lilli, R.

AU - Gottini, D.

AU - Alvarez, Javier P.

AU - García, A.

AU - Soler, Alejandro F.

AU - D’Anca, F.

AU - Guerriero, E.

AU - Del Vecchio, C.

AU - Falcini, G.

AU - Carbonaro, L.

AU - Eccleston, P.

AU - Caldwell, A.

AU - Ferruzzi, D.

AU - Malaguti, G.

AU - Micela, G.

AU - Pascale, E.

AU - Bocchieri, A.

AU - Preti, G.

AU - Piazzolla, R.

AU - Salatti, M.

AU - Brienza, D.

AU - Tommasi, E.

AU - Tinetti, G.

AU - Vernani, D.

AU - Morgante, G.

N1 - Publisher Copyright: © 2024 SPIE.

PY - 2024

Y1 - 2024

N2 - Ariel (Atmospheric Remote-Sensing Infrared Exoplanet Large Survey) is the adopted M4 mission of ESA “Cosmic Vision” program. Its purpose is to conduct a survey of the atmospheres of known exoplanets through transit spectroscopy. Launch is scheduled for 2029. Ariel scientific payload consists of an off-axis, unobscured Cassegrain telescope feeding a set of photometers and spectrometers in the waveband between 0.5 and 7.8 µm, and operating at cryogenic temperatures. The Ariel Telescope consists of a primary parabolic mirror with an elliptical aperture of 1.1 m of major axis, followed by a hyperbolic secondary, a parabolic recollimating tertiary and a flat folding mirror. The Primary mirror is a very innovative device made of lightened aluminum. Aluminum mirrors for cryogenic instruments and for space application are already in use, but never before now it has been attempted the creation of such a large mirror made entirely of aluminum: this means that the production process must be completely revised and fine-tuned, finding new solutions, studying the thermal processes and paying a great care to the quality check. By the way, the advantages are many: thermal stabilization is simpler than with mirrors made of other materials based on glass or composite materials, the cost of the material is negligeable, the shape may be free and the possibility of making all parts of the telescope, from optical surfaces to the structural parts, of the same material guarantees a perfect alignment at whichever temperature. The results and expectations for the flight model are discussed in this paper.

AB - Ariel (Atmospheric Remote-Sensing Infrared Exoplanet Large Survey) is the adopted M4 mission of ESA “Cosmic Vision” program. Its purpose is to conduct a survey of the atmospheres of known exoplanets through transit spectroscopy. Launch is scheduled for 2029. Ariel scientific payload consists of an off-axis, unobscured Cassegrain telescope feeding a set of photometers and spectrometers in the waveband between 0.5 and 7.8 µm, and operating at cryogenic temperatures. The Ariel Telescope consists of a primary parabolic mirror with an elliptical aperture of 1.1 m of major axis, followed by a hyperbolic secondary, a parabolic recollimating tertiary and a flat folding mirror. The Primary mirror is a very innovative device made of lightened aluminum. Aluminum mirrors for cryogenic instruments and for space application are already in use, but never before now it has been attempted the creation of such a large mirror made entirely of aluminum: this means that the production process must be completely revised and fine-tuned, finding new solutions, studying the thermal processes and paying a great care to the quality check. By the way, the advantages are many: thermal stabilization is simpler than with mirrors made of other materials based on glass or composite materials, the cost of the material is negligeable, the shape may be free and the possibility of making all parts of the telescope, from optical surfaces to the structural parts, of the same material guarantees a perfect alignment at whichever temperature. The results and expectations for the flight model are discussed in this paper.

KW - ARIEL mission

KW - cryogenic optics

KW - IR Space telescopes

KW - metal mirrors

KW - NiP treatment

UR - https://www.scopus.com/pages/publications/85206198125

U2 - 10.1117/12.3018855

DO - 10.1117/12.3018855

M3 - Conference paper

AN - SCOPUS:85206198125

T3 - Proceedings of SPIE - The International Society for Optical Engineering

BT - Space Telescopes and Instrumentation 2024

A2 - Coyle, Laura E.

A2 - Matsuura, Shuji

A2 - Perrin, Marshall D.

PB - SPIE

Y2 - 16 June 2024 through 22 June 2024

ER -