POET is a proposed Canadian Microsatellite mission designed to characterize and discover transiting exoplanets. A 20-cm all-reflective telescope will feed a trio of detectors to obtain simultaneous, high duty-cycle, photometry in the u (300-400 nm), Visible Near-Infrared (VNIR) (400-900 nm) and Short Wave Infrared (SWIR (900- 1700 nm) bands to make precision measurements of exoplanet transits for atmospheric characterization and to detect transiting Earth-sized planets. POET was selected as a high priority for a Microsatellite mission by the Canadian community as part of the CASCA Long Range Plan 2020. Advancement of the payload concept and technology development for the optical telescope assembly (OTA) are currently being carried out through the Space Technology Development Program of the Canadian Space Agency. POET is a collaboration between Bishop’s University, Western University, ABB and SFL-UTIAS.
With a focus on off-the-shelf components, Twinkle is the first in a series of cost competitive small satellites managed and financed by Blue Skies Space Ltd. The satellite is based on a high-heritage Airbus platform that will carry a 0.45 m telescope and a spectrometer which will provide simultaneous wavelength coverage from 0.5–4.5 μm. The spacecraft prime is Airbus Stevenage while the telescope is being developed by Airbus Toulouse and the spectrometer by ABB Canada. Scheduled to begin scientific operations in 2025, Twinkle will sit in a thermally-stable, sun-synchronous, low-Earth orbit. The mission has a designed operation lifetime of at least seven years and, during the first three years of operation, will conduct two large-scale survey programmes: one focused on Solar System objects and the other dedicated to extrasolar targets. Here we present an overview of the architecture of the mission, refinements in the design approach, and some of the key science themes of the extrasolar survey.
The United States Space Surveillance Network catalogs around 23,000 Resident Space Objects (RSOs). The completeness of their coverage of the true RSO population decreases gradually with object size and radar reflectivity. While the population of cm level space debris is poorly represented in the catalogs these space bullets can cause severe damage to satellites and spacecrafts in addition to being likely much more numerous than larger pieces. This research project focuses on the ability to peek into this debris population using space-based high sensitivity, fast frame rate, wide field visible imaging from low Earth orbit. The simulator developed focuses on a LEO to LEO (sensor to RSO) scenario and the capacity to constrain their orbit trajectory. In the Matlab simulator, a simple specular/diffuse sphere model is used for the debris in order to generate the object’s apparent magnitude for any sun-debris-observer arrangement. Satellite and debris relative velocities and orbits are also considered in order to determine the length of the streak left by the debris on any given exposure sequence and the number of photons per pixel. The exact timing, position, length and orientation of the streak contains information constraining the object’s orbit. The generation of representative star backgrounds matched to the sensor high sensitivity is also an important part of the simulator since it affects the effective limiting sensitivity to faint transiting source. This simulator allows us to trade various sensor parameters in order to optimize the camera design. The conclusion from this work contribute to the global effort in Space Situational Awareness (SSA) by assessing the impact of including space based optical imagery in the detection mix.
Current fleet of geostationary Earth orbit (GEO) satellites are used to provide communication in remote areas and to acquire meteorological data that are fed to Numerical Weather Predictions models.
Current fleet of geostationary Earth orbit (GEO) satellites are used to provide communication in remote areas and to acquire meteorological data that are fed to Numerical Weather Predictions models.
The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) is the main instrument on-board the SCISAT-1 satellite, a mission mainly supported by the Canadian Space Agency [1]. It is in Low- Earth Orbit at an altitude of 650 km with an inclination of 74E. Its data has been used to track the vertical profile of more than 30 atmospheric species in the high troposphere and in the stratosphere with the main goal of providing crucial information for the comprehension of chemical and physical processes controlling the ozone life cycle. These atmospheric species are detected using high-resolution (0.02 cm-1) spectra in the 750-4400 cm-1 spectral region. This leads to more than 170 000 spectral channels being acquired in the IR every two seconds. It also measures aerosols and clouds to reduce the uncertainty in their effects on the global energy balance. It is currently the only instrument providing such in-orbit high resolution measurements of the atmospheric chemistry and is often used by international scientists as a unique data set for climate understanding.
The satellite is in operation since 2003, exceeding its initially planned lifetime of 2 years by more than a factor of 5. Given its success, its usefulness and the uniqueness of the data it provides, the Canadian Space Agency has founded the development of technologies enabling the second generation of ACE-FTS instruments through the High Vertical Resolution Measurement (HVRM) project but is still waiting for the funding for a mission.
This project addresses three major improvements over the ACE-FTS. The first one aims at improving the vertical instantaneous field-of-view (iFoV) from 4.0 km to 1.5 km without affecting the SNR and temporal precision. The second aims at providing precise knowledge on the tangent height of the limb observation from an external method instead of that used in SCISAT-1 where the altitude is typically inferred from the monotonic CO2 concentration seen in the spectra. The last item pertains to reaching lower altitude down to 5 km for the retrieved gas species, an altitude at which the spectra are very crowded in terms of absorption. These objectives are attained through a series of modification in the optical train such as the inclusion of a field converter and a series of dedicated real-time and post-acquisition algorithms processing the Sun images as it hides behind the Earth. This paper presents the concepts, the prototypes that were made, their tests and the results obtained in this Technology Readiness Level (TRL) improvement project.
With the upcoming construction of ELTs, several existing technologies are being pushed beyond their performance limit and it became essential to develop and evaluate alternatives. We present a specifically designed focal plane box which will allow to evaluate, directly on-sky, the performance of a number of next generation adaptive optics related technologies The system will able us to compare the performance of several new wavefront sensors in contrast to a Shack-Hartman wavefront sensor. The system has been designed for the "Observatoire du Mont Mégantic" (OMM) which hosts a telescope having a 1.6-meter diameter primary. The OMM telescope, located halfway between Montreal and Quebec City, is known to be an excellent location to develop and test precursor instruments which can then be upscaled to larger telescopes (ex. SPIOMM which led to SITELLE at the CFHT). We present the results of the first run made at the telescope and also identify problems that were encountered. We also propose a series of modifications to the system that will help to solve these issues.
WFIRST-AFTA is the NASA’s highest ranked astrophysics mission for the next decade that was identified in the New
World, New Horizon survey. The mission scientific drivers correspond to some of the deep questions identified in the
Canadian LRP2010, and are also of great interest for the Canadian scientists. Given that there is also a great interest in
having an international collaboration in this mission, the Canadian Space Agency awarded two contracts to study a
Canadian participation in the mission, one related to each instrument. This paper presents a summary of the technical
contributions that were considered for a Canadian contribution to the coronagraph and wide field instruments.
With the upcoming construction of Extremely Large Telescopes, several existing technologies are being pushed beyond their performance limit and it becomes essential to develop and evaluate new alternatives. The "Observatoire du Mont Mégantic" (OMM) hosts a telescope having a 1.6-meter diameter primary. The OMM telescope is known to be an excellent location to develop and test precursor instruments which are then upscaled to larger telescopes (ex. SPIOMM which led to SITELLE at the CFHT). We present a specifically designed focal plane box for the OMM which will allow to evaluate, directly on-sky, the performance of a number of next generation adaptive optics related technologies The system will able us to compare the performance of several new wavefront sensors in contrast with the current standard, the Shack-Hartman wavefront sensor.
The Gemini Planet Imager (GPI) has as its science instrument an infrared integral field spectrograph/polarimeter (IFS). Integral field spectrographs are scientificially powerful but require sophisticated data reduction systems. For GPI to achieve its scientific goals of exoplanet and disk characterization, IFS data must be reconstructed into high quality astrometrically and photometrically accurate datacubes in both spectral and polarization modes, via flexible software that is usable by the broad Gemini community. The data reduction pipeline developed by the GPI instrument team to meet these needs is now publicly available following GPI’s commissioning.
This paper, the first of a series, provides a broad overview of GPI data reduction, summarizes key steps, and presents the overall software framework and implementation. Subsequent papers describe in more detail the algorithms necessary for calibrating GPI data. The GPI data reduction pipeline is open source, available from planetimager.org, and will continue to be enhanced throughout the life of the instrument. It implements an extensive suite of task primitives that can be assembled into reduction recipes to produce calibrated datasets ready for scientific analysis. Angular, spectral, and polarimetric differential imaging are supported. Graphical tools automate the production and editing of recipes, an integrated calibration database manages reference files, and an interactive data viewer customized for high contrast imaging allows for exploration and manipulation of data.
INO has designed, assembled and tested the Raven Multi-Object Adaptive Optics demonstrator calibration unit. This
sub-system consists in a telescope simulator that will allow aligning Raven's components during its integration, testing
its Adaptive Optics performances in the laboratory and at the telescope, and calibrating the Adaptive Optics system by
building the interaction matrix and measuring the non-common path aberrations. The system is presented with the
challenges that needed to be overcome during the design and integration phases. The system test results are also
presented and compared to the model predictions.
The success of the high resolution nightglow studies conducted with the Keck telescopes on Mauna Kea and the Very
Large Telescopes in Chile led to the design of the Compact Echelle Spectrograph for Aeronomical Research (CESAR).
This is an echelle spectrograph with grating post-dispersion that will be dedicated to nightglow studies at high spectral
resolution (R ~ 20000) between 300-1000 nm, and that will be easily deployable at different sites. The development of
CESAR is conducted by SRI International, and INO is involved in the optical design and integration of the spectrograph
camera, whose all-spherical form is based on the camera of the HIRES spectrograph at the Keck I telescope. The
detailed optical design is used to calculate the position of the spectral elements on the detector, predict their image
quality, and estimate the level of stray light. This paper presents the methodology used in these analyses.
The Gemini Planet Imager (GPI) high-contrast adaptive optics system, which is currently under construction
for Gemini South, has an IFS as its science instrument. This paper describes the data reduction pipeline of the
GPI science instrument. Written in IDL, with a modular architecture, this pipeline reduces an ensemble of highcontrast
spectroscopic or polarimetric raw science images and calibration data into a final dataset ready for
scientific analysis. It includes speckle suppression techniques such as angular and spectral differential imaging
that are necessary to achieve extreme contrast performances for which the instrument is designed. This paper
presents also raw GPI IFS simulated data developed to test the pipeline.
The science instrument for GPI (Gemini Planet Imager) is a cryogenic integral field spectrograph
based on a lenslet array. The integral field nature of the instrument allows for a full mapping of the
focal plane at coarse spectral resolution. With such a data cube, artifacts within the PSF such as
residual speckles can be suppressed. Additionally, the initial detection of any candidate planet will
include spectral information that can be used to distinguish it from a background object: candidates
can be followed up with detailed spectroscopic observations. The optics between the lenslet array
and the detector are essentially a standard spectrograph with a collimating set of lenses, a dispersive
prism and a camera set of lenses in a folded assembly. We generally refer to this optical set as the
spectrograph optics. This paper describes the laboratory optical performances over the field of view.
The test procedure includes the imaging performances in both non dispersive and dispersive mode.
The test support equipments include a test cryostat, an illumination module with monochromatic
fiber laser, a wideband light source and a test detector module.
Quasi-static speckles are the main source of noise preventing the direct detection of exoplanets around bright stars. We
are investigating the use of an infrared (1.5-2.4 μm) integral field spectrograph (IFS) specialised for speckle suppression
and the detection of self-luminous giant planets. This paper presents the optical design and laboratory results obtained
with a TIGER-type IFS prototype based on a microlens array. A similar IFS will be used for the Gemini Planet Imager
(GPI). Preliminary speckle-suppression performances of the IFS along with simulations are presented.
Direct detection of extrasolar Jovian planets is a major scientific motivation for the construction of future extremely
large telescopes such as the Thirty Meter Telescope (TMT). Such detection will require dedicated high-contrast AO
systems. Since the properties of Jovian planets and their parent stars vary enormously between different populations, the
instrument must be designed to meet specific scientific needs rather than a simple metric such as maximum Strehl ratio.
We present a design for such an instrument, the Planet Formation Imager (PFI) for TMT. It has four key science
missions. The first is the study of newly-formed planets on 5-10 AU scales in regions such as Taurus and Ophiucus -
this requires very small inner working distances that are only possible with a 30m or larger telescope. The second is a
robust census of extrasolar giant planets orbiting mature nearby stars. The third is detailed spectral characterization of
the brightest extrasolar planets. The final targets are circumstellar dust disks, including Zodiacal light analogs in the
inner parts of other solar systems. To achieve these, PFI combines advanced wavefront sensors, high-order MEMS
deformable mirrors, a coronagraph optimized for a finely- segmented primary mirror, and an integral field spectrograph.
We present details of optical design, opto-mechanical design and testing of a visible-NIR imaging optical system for a Fourier transform spectrometer dedicated to astronomical application at the Mont Megantic Observatory (Observatoire du Mont Megantic, OMM, located south Quebec city, Canada). Design considerations as well as testing and experimental results are presented.
Primary mirrors of the next generation of extremely large telescopes will be highly segmented. Since these telescopes will be equipped with adaptive optics (AO), it is very important to examine in details what are the consequences of different segmentation schemes on the delivered image quality after AO correction. We do so using our analytical AO simulation code PAOLA {Performance of Adaptive Optics for Large (or Little) Apertures}, upgraded to include AO correction of the primary mirror static aberrations. This study allows us to derive requirements on the geometry of the primary mirror, and the maximum acceptable segments positioning and figuring errors knowing that part of their amplitude will be corrected by the AO system offset. The first important issue is the influence of the segments size and gap width. These parameters have indeed a strong impact on
the structure of the wings of the diffraction limited point spread function (PSF), but on the other hand, with the smooth AO residual halo superimposed onto it, the relative importance of the wing structures is decreased. To assess these effects, we consider the case of an AO system working in a near infrared classical mode on a 30-m segmented telescope and examine how the encircled energy radius and image contrast evolve with segment size and gap width. The second important issue is the effect of residual segment positioning & figuring errors after active optics and AO correction. Using appropriate metrics, we characterise the maximum acceptable segment positioning & figuring errors residuals in a classical AO mode, for one of the pupils studied in the first part of our work.
As part of the integrated modeling effort on the Canadian Very Large Optical Telescope described in Roberts et al. an optical modeling toolbox has been developed for the prediction of the telescope's optical performance. The toolbox, which includes a linear optical model, is written in the Matlab environment with the raytracing performed by the commercial optical design program ZEMAX. This article describes the data structures, optical merit functions, and algorithms used within the optical toolbox.
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