The Cosmological Advanced Survey Telescope for Optical and UV Research (CASTOR) is a proposed space telescope mission led by the Canadian Space Agency. With its 1-meter diameter primary mirror, CASTOR would provide imaging capabilities in the ultraviolet (UV) and blue-optical regions at a spatial resolution similar to that of the Hubble Space Telescope (FWHM of 0.15 arcseconds), but over an instantaneous field of view about 100 times larger.[3] CASTOR was selected as Canada's highest priority for space astronomy in the 2020s in the 2020 Long Range Plan for Canadian Astronomy.[4]

CASTOR
Mission typeAstronomy
OperatorCanadian Space Agency
Mission duration5 years minimum[1]
Spacecraft properties
Launch mass1063 kg[2]
Payload mass618 kg
Start of mission
Launch datelate 2020s
Orbital parameters
Reference systemGeocentric
RegimeSun-synchronous orbit
Altitude800 km
Main telescope
TypeThree-mirror anastigmat
Diameter1.0 m
WavelengthsFrom 150 nm (ultraviolet) to 550 nm (visible light)[2]
Instruments
wide-field imaging, slitless spectroscopy, DMD spectroscopy, precision photometry

Description

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CASTOR will complement the upcoming Nancy Grace Roman Space Telescope, Euclid space telescope, and Vera C. Rubin Observatory. These three major wide-field imaging facilities will not have access to the UV portion of the electromagnetic spectrum. CASTOR has been specifically designed to provide this missing capability, with high sensitivity and observing efficiency at UV and blue-optical wavelengths.[3]

Using dichroics, CASTOR would enable simultaneous imaging of three bandpasses (UV from 150 to 300 nm, u from 300 to 400 nm, and g from 400 to 550 nm) over an instantaneous field of view of 0.25 square degrees. In addition to its imaging capabilities, CASTOR will also be equipped with additional instruments enabling high-precision photometry for the monitoring of bright targets, as well as two spectroscopic modes: low-spectral-resolution slitless spectroscopy over the entire imaging field and configurable DMD spectroscopy to provide intermediate resolution spectra in the UV in a parallel field.[2]

Objectives

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Specific science drivers of CASTOR include:[5]

References

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  1. ^ Côte, Patrick; Scott, Alan; Balogh, Michael; Buckingham, Ron; Aldridge, David; Carlberg, Ray; Chen, Weiguo; Dupuis, Jean; Evans, Clinton; Drissen, Laurent; Fraser, Wes; Grandmont, Frederic; Harrison, Paul; Hutchings, John; Kavelaars, JJ; Landry, John-Thomas; Lange, Christian; Laurin, Denis; Patel, Tarun; Pillay, Venka; Piche, Louis; Rader, Andres; Robert, Carmelle; Sawicki, Marchin; Sorba, Robert; Theriault, Guillaume; Van Waerbeke, Ludovic (2012). "CASTOR: the Cosmological Advanced Survey Telescope for Optical and Ultraviolet Research". In Clampin, Mark C.; Fazio, Giovanni G.; MacEwen, Howard A.; Oschmann, Jacobus M. (eds.). Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave. Vol. 8442. SPIE. p. 844215. doi:10.1117/12.926198. S2CID 119902782. Retrieved 2022-07-04.
  2. ^ a b c "CASTOR Mission Specifications". Retrieved 2022-07-04.
  3. ^ a b "CASTOR: A Flagship Canadian Space Telescope". Retrieved 2022-07-04.
  4. ^ "Canadian Astronomy Long Range Plan" (PDF). Retrieved 2022-07-04.
  5. ^ "CASTOR Science". Retrieved 2022-07-04.
  6. ^ Graham, Melissa L.; Connolly, Andrew J.; Wang, Winnie; Schmidt, Samuel J.; Morrison, Christopher B.; Ivezić, Željko; Fabbro, Sébastien; Côté, Patrick; Daniel, Scott F.; Jones, R. Lynne; Jurić, Mario; Yoachim, Peter; Kalmbach, J. Bryce (2020-05-13). "Photometric Redshifts with the LSST. II. The Impact of Near-infrared and Near-ultraviolet Photometry". The Astronomical Journal. 159 (6). American Astronomical Society: 258. arXiv:2004.07885. Bibcode:2020AJ....159..258G. doi:10.3847/1538-3881/ab8a43. ISSN 1538-3881. S2CID 215814361.
  7. ^ Fantin, Nicholas J.; Côté, Patrick; McConnachie, Alan W. (2020-09-09). "White Dwarfs in the Era of the LSST and Its Synergies with Space-based Missions". The Astrophysical Journal. 900 (2). American Astronomical Society: 139. arXiv:2007.01312. Bibcode:2020ApJ...900..139F. doi:10.3847/1538-4357/aba270. ISSN 1538-4357.
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