The Unit Telescope (UT) for the Magdalena Ridge Observatory (MROI) is composed of four major hardware components: The Unit Telescope Mount (UTM), Enclosure, Optics and the Fast Tip Tilt System (FTTS). Integration of the UT started in 2016 when the UTM arrived and its Assembly, Integration and Verification activities began. Critical activities included: installation at the Maintenance Facility, integration and alignment of the Optics and Wave Front Sensor (WFS) and finally the complete optical alignment. End-to-end UTM Site Acceptance Tests (SAT) were performed. Subsequent activities included receiving and integrating the FTTS. With the arrival and assembly of the Enclosure, the last component of the UT was ready for integration on a dedicated concrete pier. Specialized equipment will be used for the final integration of the UT, and for transportation to its final location on the array where SAT for the UT will take place.
The Magdalena Ridge Observatory Interferometer (MROI) has been under development for almost two decades. Initial funding for the facility started before the year 2000 under the Army and then Navy, and continues today through the Air Force Research Laboratory. With a projected total cost of substantially less than $200M, it represents the least expensive way to produce sub-milliarcsecond optical/near-infrared images that the astronomical community could invest in during the modern era, as compared, for instance, to extremely large telescopes or space interferometers. The MROI, when completed, will be comprised of 10 x1.4m diameter telescopes distributed on a Y-shaped array such that it will have access to spatial scales ranging from about 40 milliarcseconds down to less than 0.5 milliarcseconds. While this type of resolution is not unprecedented in the astronomical community, the ability to track fringes on and produce images of complex targets approximately 5 magnitudes fainter than is done today represents a substantial step forward. All this will be accomplished using a variety of approaches detailed in several papers from our team over the years. Together, these two factors, multiple telescopes deployed over very long-baselines coupled with fainter limiting magnitudes, will allow MROI to conduct science on a wide range and statistically meaningful samples of targets. These include pulsating and rapidly rotating stars, mass-loss via accretion and mass-transfer in interacting systems, and the highly-active environments surrounding black holes at the centers of more than 100 external galaxies. This represents a subsample of what is sure to be a tremendous and serendipitous list of science cases as we move ahead into the era of new space telescopes and synoptic surveys. Additional investigations into imaging man-made objects will be undertaken, which are of particular interest to the defense and space-industry communities as more human endeavors are moved into the space environment.
In 2016 the first MROI telescope was delivered and deployed at Magdalena Ridge in the maintenance facility. Having undergone initial check-out and fitting the system with optics and a fast tip-tilt system, we eagerly anticipate installing the telescope enclosure in 2018. The telescope and enclosure will be integrated at the facility and moved to the center of the interferometric array by late summer of 2018 with a demonstration of the performance of an entire beamline from telescope to beam combiner table shortly thereafter. At this point, deploying two more telescopes and demonstrating fringe-tracking, bootstrapping and limiting magnitudes for the facility will prove the full promise of MROI. A complete status update of all subsystems follows in the paper, as well as discussions of potential collaborative initiatives.
The deployment of the Magdalena Ridge Observatory Interferometer has resumed in 2016. AMOS, in charge of the development of the unit telescopes, has completed the installation of the first telescope on the Ridge. The compactness of the system allows for a fast installation, as only the optics and their supports need to be transported in separate crates. The installation has been followed by the alignment procedure combining metrological and optical measurement techniques and aiming at optimizing the pupil stability and image quality. Finally, the performance of the telescope has been evaluated on the sky as part of the site acceptance.
NESSI (New Mexico Exoplanet Spectroscopic Survey Instrument) was originally conceived, designed and built under a NASA NM-EPSCoR funded effort as a near-infrared multi-object spectrograph for characterizing exoplanet transits at the Magdalena Ridge Observatory. With the help of funding from JPL, we are moving NESSI to its new home on the Hale telescope in early 2018. Salient features of the New NESSI include a 6.5 arc minute field-of-view, low (R~250) or moderate (R~1100) spectral resolutions across J, H and/or K bands, the ability to stare at transits with high frame-rates, and finally a suite of on-board filters for imaging applications. We present the new design of NESSI, lessons learned in the refurbishment process, as well as an update for next steps in the process.
The Magdalena Ridge Observatory Interferometer (MROI) was the most ambitious infrared interferometric facility conceived of in 2003 when funding began. Today, despite having suffered some financial short-falls, it is still one of the most ambitious interferometric imaging facilities ever designed. With an innovative approach to attaining the original goal of fringe tracking to H = 14th magnitude via completely redesigned mobile telescopes, and a unique approach to the beam train and delay lines, the MROI will be able to image faint and complex objects with milliarcsecond resolutions for a fraction of the cost of giant telescopes or space-based facilities. The design goals of MROI have been optimized for studying stellar astrophysical processes such as mass loss and mass transfer, the formation and evolution of YSOs and their disks, and the environs of nearby AGN.
The global needs for Space Situational Awareness (SSA) have moved to the forefront in many communities as Space becomes a more integral part of a national security portfolio. These needs drive imaging capabilities ultimately to a few tens of centimeter resolution at geosynchronous orbits. Any array capable of producing images on faint and complex geosynchronous objects in just a few hours will be outstanding not only as an astrophysical tool, but also for these types of SSA missions. With the recent infusion of new funding from the Air Force Research Lab (AFRL) in Albuquerque, NM, MROI will be able to attain first light, first fringes, and demonstrate bootstrapping with three telescopes by 2020.
MROI’s current status along with a sketch of our activities over the coming 5 years will be presented, as well as clear opportunities to collaborate on various aspects of the facility as it comes online. Further funding is actively being sought to accelerate the capability of the array for interferometric imaging on a short time-scale so as to achieve the original goals of this ambitious facility
The fast tip-tilt (FTT) correction system for the Magdalena Ridge Observatory Interferometer (MROI) is being developed by the University of Cambridge. The design incorporates an EMCCD camera protected by a thermal enclosure, optical mounts with passive thermal compensation, and control software running under Xenomai real-time Linux. The complete FTT system is now undergoing laboratory testing prior to being installed on the first MROI unit telescope in the fall of 2014. We are following a twin-track approach to testing the closed-loop performance: tracking tip-tilt perturbations introduced by an actuated flat mirror in the laboratory, and undertaking end-to-end simulations that incorporate realistic higher-order atmospheric perturbations. We report test results that demonstrate (a) the high stability of the entire opto-mechanical system, realized with a completely passive design; and (b) the fast tip-tilt correction performance and limiting sensitivity. Our preliminary results in both areas are close to those needed to realise the ambitious stability and sensitivity goals of the MROI which aims to match the performance of current natural guide star adaptive optics systems.
The Magdalena Ridge Observatory Interferometer has been designed to be a 10 × 1.4 m aperture long-baseline optical/near-infrared interferometer in an equilateral "Y" configuration, and is being deployed west of Socorro, NM on the Magdalena Ridge. Unfortunately, first light for the facility has been delayed due to the current difficult funding regime, but during the past two years we have made substantial progress on many of the key subsystems for the array. The design of all these subsystems is largely complete, and laboratory assembly and testing, and the installation and site acceptance testing of key components on the Ridge are now underway. This paper serves as an overview and update on the facility's present status and changes since 2012, and the plans for future activities and eventual operations of the facilities.
NESSI: the New Mexico Tech Extra(solar)planet Spectroscopic Survey Instrument is a ground-based multi-object
spectrograph that operates in the near-infrared and is being deployed this fall at the Magdalena Ridge Observatory 2.4 m
telescope. When completed later this year, it is expected to be used to characterize the atmospheres of transiting
exoplanets with unprecedented ground-based accuracies down to about K = 9 magnitude. The superior capabilities of
NEESI for this type of work lay, in part, in the design philosophy used for the instrument which is well-focused on the
exoplanet case. We report here on this design philosophy, detail and status of the design and assembly, and preparation
for first light in the fall of 2012.
NESSI: the New Mexico Tech Extrasolar Spectroscopic Survey Instrument is a ground-based multi-object
spectrograph that operates in the near-infrared. It will be installed on one of the Nasmyth ports of the
Magdalena Ridge Observatory (MRO) 2.4-meter Telescope. NESSI operates stationary to the telescope
fork so as not to produce differential flexure between internal opto-mechanical components during or
between observations. In this paper we report on NESSI's detailed mechanical and opto-mechanical design,
and the planning for mechanical construction, assembly, integration and verification.
The Magdalena Ridge Observatory Interferometer has been designed to be a 10 x 1.4 m aperture long-baseline
optical/near-infrared interferometer in an equilateral "Y" configuration, and is being deployed west of Socorro, NM on
the Magdalena Ridge. Unfortunately, first light for the facility has been delayed due to the current difficult funding
regime, but during the past two years we have made substantial progress on many of the key subsystems for the array.
The design of all these subsystems is largely complete, and laboratory assembly and testing, and the installation of many of its components on the Ridge are now underway. This paper serves as an overview and update on the facility's present status, and the plans for future funding and eventual operations of the facilities.
Most subsystems of the Magdalena Ridge Observatory Interferometer (MROI) have progressed towards
final mechanical design, construction and testing since the last SPIE meeting in San Diego - CA. The first
1.4-meter telescope has successfully passed factory acceptance test, and construction of telescopes #2 and
#3 has started. The beam relay system has been prototyped on site, and full construction is awaiting
funding. A complete 100-meter length delay line system, which includes its laser metrology unit, has been
installed and tested on site, and the first delay line trolley has successfully passed factory acceptance
testing. A fully operational fringe tracker is integrated with a prototyped version of the automated
alignment system for a closed looping fringe tracking experiment. In this paper, we present details of the
final mechanical and opto-mechanical design for these MROI subsystems and report their status on
fabrication, assembly, integration and testing.
The fast tip-tilt correction system for the Magdalena Ridge Observatory Interferometer (MROI) is being designed and fabricated by the University of Cambridge. The design of the system is currently at an advanced stage and the performance of its critical subsystems has been verified in the laboratory. The system has been designed to meet a demanding set of specifications including satisfying all performance requirements in ambient temperatures down to -5 °C, maintaining the stability of the tip-tilt fiducial over a 5 °C temperature change without recourse to an optical reference, and a target acquisition mode with a 60” field-of-view. We describe the important technical features of the system, which uses an Andor electron-multiplying CCD camera protected by a thermal enclosure, a transmissive optical system with mounts incorporating passive thermal compensation, and custom control software running under Xenomai real-time Linux. We also report results from laboratory tests that demonstrate (a) the high stability of the custom optic mounts and (b) the low readout and compute latencies that will allow us to achieve a 40 Hz closed-loop bandwidth on bright targets.
The Magdalena Ridge Observatory Interferometer is a 10 x 1.4 meter aperture long baseline optical and near-infrared
interferometer being built at 3,200 meters altitude on Magdalena Ridge, west of Socorro, NM. The interferometer layout
is an equilateral "Y" configuration to complement our key science mission, which is centered on imaging faint and
complex astrophysical targets. This paper serves as an overview and update on the status of the observatory and our
progress towards first light and first fringes in 2012.
The MROI fringe tracking beam combiner will be the first fringe instrument for the interferometer. It was designed to
utilize the array geometry and maximize sensitivity to drive the interferometer for faint source imaging. Two primary
concerns have driven the design philosophy: 1) maintaining high throughput and visibilities in broadband polarized light,
and 2) mechanical stability. The first concern was addressed through tight fabrication tolerances of the combiner substrates, and custom coatings. In order to optimize mechanical stability, a unique modular design approach was taken that minimizes the number of internal adjustments. This paper reports initial laboratory fringe and stability measurements.
The Magdalena Ridge Observatory Interferometer (MROI) has completed its design phase and is currently in the
construction phase. The first telescope will be deployed at the MROI site in 2011. Five different vendors are involved
in the design and fabrication of a unit telescope, and a much larger number for the full observatory.
This paper addresses the steps that the MRO Interferometry project will undertake to integrate subsystems developed by
different parties, through commissioning into an operational optical interferometer.
Finally we present the commissioning plan to bring the interferometer to an operational mode. We have developed
"performance verification milestones" that successively increase the "science readiness" of the interferometer and
transitions to an operational phase.
Here is presented the current outline and progress of MROI's automated alignment system design. Depending on the
location of each of MROI's unit telescopes (UT), light can travel distances ranging from 460 to 660 meters via
several reflections that redirect the beam's path through the beam relay system (BRS), delay line system (DLS),
beam compressing telescope (BCR), switchyards and finally to the beam combiners (BC). All of these sub-systems
comprise three major optical axes of the MROI which must be coaligned on a nightly basis by the AAS. The AAS
consists of four subsystems: the primary fiducial-for beam injection, the UT tilt and shear measurement
components (TASM), the BC TASM components, and the secondary fiducial-for quick alignment checks. All of
these subsystems contribute to the unique design of the AAS which will allow for simultaneous measurements from
the visible to the near-IR wavelengths, full automation, the capability to perform optical path difference (OPD)
alignment and spectral calibration, making it cost effective and saving on realty in the beam combining area (BCA).
The AAS is nearing completion and assembly of the various subsystems is expected to commence soon. The latest
results on all of the following are reviewed here.
We report on the mechanical design currently performed at the Magdalena Ridge Observatory
Interferometer (MROI) and how the construction, assembly, integration and verification are planned
towards commissioning. Novel features were added to the mechanical design, and high level of automation
and reliability are being devised, which allows the number of reflections to be kept down to a minimum
possible. This includes unit telescope and associated enclosure and transporter, fast tip-tilt system, beam
relay system, delay line system, beam compressor, automated alignment system, beam turning mirror,
switchyard, fringe tracker and vacuum system.
We present the verification procedure for the 1.4 meter primary mirrors of the Magdalena Ridge Observatory
Interferometer (MROI). Six mirrors are in mass production at Optical Surface Technologies (OST) in Albuquerque.
The six identical parabolic mirrors will have a radius of curvature of 6300 mm and a final surface wavefront quality of
29 nm rms.
The mirrors will be tested in a tower using a computer generated hologram, and the Intellium™ H2000 interferometer
from Engineering Synthesis Design, Inc. (ESDI). The mirror fabrication activities are currently in the early stage of
polishing and have already delivered some promising results with the interferometer. A complex passive whiffle tree
has been designed and fabricated by Advanced Mechanical and Optical Systems (AMOS, Belgium) that takes into
account the gravity loading for an alt-alt mount. The final testing of the primary mirrors will be completed with the
mirror cells that will be used in the telescopes.
In addition we report on shear tests performed on the mirror cell pads on the back of the primary mirrors. These pads are
glued to the mirror. The shear test has demonstrated that the glue can withstand at least 4.9 kilo Newton. This is within
The Magdalena Ridge Observatory Interferometer is a 10-element 1.4 meter aperture optical and near-infrared
interferometer being built at 3,200 meters altitude on Magdalena Ridge, west of Socorro, NM. The
interferometer layout is an equilateral "Y" configuration to complement our key science mission, which is
centered around imaging faint and complex astrophysical targets. This paper serves as an overview and
update on the status of the observatory and our progress towards first light and first fringes in the next few