The CASTOR mission

instrumentation; space vehicles; surveys; telescopes; ultraviolet; Canadian Space Agency; High resolution; Instrumentation; National Research Council of Canada; Optical wavelength; Space vehicles; Spectral region; Three channel; Ultraviolet; Wide-field; Electronic, Optical and Magnetic Materials; Control and Systems Engineering; Astronomy and Astrophysics; Mechanical Engineering; Space and Planetary Science

Abstract :

[en] CASTOR is a proposed wide-field (300 × 300 ¼ 0.25 deg2), high-resolution (FWHM ∼ 0.1500), 1-m-diameter space telescope that is under development by the Canadian Space Agency and the National Research Council of Canada. Optimized for UV/blue-optical wavelengths, the telescope uses dichroics to enable imaging in three channels (and up to five bands) that cover the 0.15 to 0.55 μm spectral region, simultaneously. CASTOR will also feature low- and low-medium-resolution spectroscopic capabilities through the use of a deployable grism for low-resolution (R ≲ 420) slit-less spectroscopy in its UV and u channels, and low-medium-resolution R ∼ 1400 multi-object spectroscopy in a parallel field using a digital micro-mirror device. High-speed, precision photometry will be possible using dedicated CMOS detectors in each of its three channels. We present an overview of the mission, including the optical design, instruments and detectors, payload layout, satellite bus, orbit, and ground segment. We describe the mission’s scientific capabilities and expected place within the astronomical landscape in the 2030s. The 5-year lifetime is baselined on a combination of legacy surveys, guest observer programs, and target-of-opportunity science. We summarize scientific plans for the mission in each of eight fields: cosmology, time domain and multi-messenger science, active galactic nuclei, galaxies, near-field cosmology, stellar astrophysics, exoplanets, and solar system studies. We conclude by describing ongoing development efforts, highlighting areas of particular relevance for NASA’s Habitable Worlds Observatory.

Research Center/Unit :

STAR - Space sciences, Technologies and Astrophysics Research - ULiège

Disciplines :

Space science, astronomy & astrophysics

Author, co-author :

Côté, Patrick ; National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre, Victoria, Canada

Woods, Tyrone E. ; University of Manitoba, Department of Physics and Astronomy, Winnipeg, Canada

Hutchings, John B.; National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre, Victoria, Canada

Rhodes, Jason D. ; California Institute of Technology, Jet Propulsion Laboratory, Pasadena, United States

Sánchez-Janssen, Rubén; UK Astronomy Technology Centre, Royal Observatory, Edinburgh, United Kingdom

Scott, Alan D. ; Honeywell Aerospace, Cambridge, Canada

Pazder, John; National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre, Victoria, Canada

Amenouche, Melissa ; Université de Liège - ULiège > Unités de recherche interfacultaires > Space sciences, Technologies and Astrophysics Research (STAR) ; National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre, Victoria, Canada

Balogh, Michael ; University of Waterloo, Department of Physics and Astronomy, Waterloo, Canada ; University of Waterloo, Waterloo Centre for Astrophysics, Waterloo, Canada

Blouin, Simon ; University of Victoria, Department of Physics and Astronomy, Victoria, Canada

More authors (170 more)

Language :

English

Title :

The CASTOR mission

Publication date :

October 2025

Journal title :

Journal of Astronomical Telescopes, Instruments, and Systems

ISSN :

2329-4124

eISSN :

2329-4221

Publisher :

SPIE

Volume :

Issue :

Pages :

id042202 (37p)

Peer reviewed :

Peer Reviewed verified by ORBi

Additional URL :

https://www.spiedigitallibrary.org/journals/Journal-of-Astronomical-Telescopes-Instruments-and-Systems/volume-11/issue-04/042202/The-CASTOR-mission/10.1117/1.JATIS.11.4.042202.full

Funders :

Canadian Space Agency
National Research Council of Canada
Jet Propulsion Laboratory
California Institute of Technology
UK Space Agency
Science and Technology Facilities Council’s UK Astronomy Technology Centre
National Aeronautics and Space Administration

Funding text :

Support for this work was provided by the National Research Council of Canada and the Canadian Space Agency. Early UK participation in CASTOR was funded by the UK Space Agency as part of the newly established Science and Exploration Bilateral Programme. The CASTOR: UK consortium is led and managed by STFC\u2019s UK Astronomy Technology Centre (UKATC). Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (Grant No. 80NM0018D0004). Early UK participation in CASTOR was funded by the UK Space Agency as part of the newly established Science and Exploration Bilateral Programme. The CASTOR:UK consortium is led and managed by the Science and Technology Facilities Council\u2019s UK Astronomy Technology Centre (UKATC). AIM is supported by Schmidt Sciences. We dedicate this paper to the memory of John Hutchings, a tireless champion of space astronomy and a driving force behind the development of the CASTOR mission.Early UK participation in CASTOR was funded by the UK Space Agency as part of the newly established Science and Exploration Bilateral Programme. The CASTOR:UK consortium is led and managed by the Science and Technology Facilities Council\u2019s UK Astronomy Technology Centre (UKATC).Early UK participation in CASTOR was funded by the UK Space Agency as part of the newly established Science and Exploration Bilateral Programme. The CASTOR: UK consortium is led and managed by STFC\u2019s UK Astronomy Technology Centre (UKATC). Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (Grant No. 80NM0018D0004).

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