The Fast Auroral Imager (FAI) consists of two charge-coupled device (CCD) cameras: one to measure the 630 nm emission of atomic oxygen in aurora and enhanced night airglow; and the other to observe the prompt auroral emissions in the 650 to 1100 nm range. High sensitivity is realized through the combination of fast lens systems (f/0.8) and CCDs of high quantum efficiency (>90 % max). The cameras have a common 26 degree field-of-view to provide nighttime images of about 650 km diameter from apogee at 1500 km. The near infrared camera provides up to two images of 0.1 s exposure per second with a spatial resolution of a few km when the camera is pointing in the nadir direction, making it suitable for studies of dynamic auroral phenomena. The 630-nm camera has been designed to provide one image of 0.5 s exposure every 30 seconds. Launch of the satellite occurred on September 29, 2013. Following a description of the instrument, sample auroral images are presented.

The Cosmological Advanced Survey Telescope for Optical and uv Research (CASTOR) is a proposed CSA-led mission that would carry out panoramic imaging in the ultraviolet and blue-optical region (≈ 150–550 nm). Operating close to the diffraction limit, the 1m CASTOR telescope would have a spatial resolution comparable to the Hubble Space Telescope (HST), but with an instantaneous field of view about two hundred times larger. The scientific impact from such a facility would be immense, covering topics ranging from small bodies in the outer solar system to the equation of state of the universe. CASTOR has the potential to be a significant, unique and highly strategic Canadian contribution to the international portfolio of astronomical facilities in the 2020s, complementing highprofile optical/IR space missions (Euclid, WFIRST) and ground-based telescopes (LSST) currently under development in Europe and the United States. By placing Canada at the forefront of astronomical research in the coming decade, CASTOR would showcase the technological capabilities of Canadian industries to an international audience, and inspire the next generation of young Canadians to pursue careers in science, engineering and technology. To achieve maximum scientific impact, and to enable effective international partnerships (including collaborations with the Euclid, LSST and WFIRST development teams), CASTOR should launch no later than the middle of the next decade. Since the time of the 2010 Long Range Plan for Canadian Astronomy, CSA has taken significant steps to advance CASTOR through the mission concept stage, including ongoing technology development studies. However, it is now imperative that CASTOR moves promptly to a Phase 0 study in order to refine estimates for cost and schedule, optimize the mission design and survey strategies, and lay the groundwork for international partnerships. Subject headings: telescopes – satellites – instrumentation – techniques – surveys – cosmology – dark energy – dark matter – galaxies – stellar astrophysics – planetary systems – solar system – ultraviolet, optical and infrared astronomy – time domain astronomy 1. BACKGROUND AND CONTEXT In the next decade, two landmark space missions will transform astronomy by carrying out deep, high1 NRC Herzberg Astronomy & Astrophysics, 5071W. Saanich Road, Victoria, BC 2 COM DEV Ltd, 303 Terry Fox Drive, Kanata, ON 3 Department of Astronomy, University of Toronto, 50 St. George Street, Toronto, ON 4 Magellan Aerospace, 3160 Derry Road East, Mississauga, ON 5 Department of Physics and Astronomy, University of Waterloo, Waterloo, ON 6 Northeast Space Company Inc., Box 355 – 900 Greenbank Road, Ottawa, ON 7 Department of Mechanical & Aeronautical Engineering, Clarkson University, Potsdam, New York 8 B-Con Engineering Inc., 14 Capella Court, Nepean, ON 9 Canadian Space Agency, 6767 Boulevard de l’Aroport, SaintHubert, QC 10 Département de Physique, de Génie Physique et d’Optique, Université Laval, QC 11 Xiphos Technologies, 3981 St.Laurent Boulevard, Suite 500, Montreal, QC 12 ABB Analytical, 585 Boulevard Charest Est, Suite 300, Québec, QC 13 Department of Astronomy and Physics and Institute for Computational Astrophysics, Saint Mary’s University, 923 Robie Street, Halifax, NS 14 Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC 15 BMV Optical Technologies, 26 Concourse Gate, Ottawa, ON resolution, wide-field imaging in the red-optical and infrared (IR) spectral region (0.55 ≤ λ . 2 μm). The first of these, Euclid, is an ESA-led mission that is scheduled for launch in 2020 (Laureijs et al. 2011). Euclid will image an area of at least 15 000 deg in the IR region (Y JH), as well as in a single broad filter (VIS) at red-optical wavelengths. Around 2023, Euclid will be joined by NASA’s WFIRST mission (Spergel et al. 2013), which will also carry out red-optical/IR imaging (Y JH and F184), but to a depth ∼ 3 mag deeper than Euclid over a smaller (' 2200 deg) field. Both missions are primarily motivated by a desire to understand dark energy — a mysterious component of the universe that causes an acceleration in the cosmic expansion rate — but their legacy value is so immense that a vast amount of ancillary science will be enabled. On the ground, the Large Synoptic Survey Telescope (LSST) is expected to begin its decade-long survey operations in 2022. LSST (Ivezić et al. 2008, Abell et al. 2009) will revolutionize time-domain astronomy by repeatedly imaging an area of ∼ 20 000 deg every few nights. The combination of optical imaging from LSST and IR imaging from Euclid/WFIRST is expected to be a powerful resource that astronomers will exploit for decades to come. Indeed, LSST and WFIRST emerged as the topranked projects in groundand space-based astronomy