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We report the current status of the laser guide star upgrade at Subaru Telescope with a new, more powerful TOPTICA/MPBC laser. While we recycle many of our existing components, such as laser launch telescope, we need to design a new mirror-based laser relay system to replace the current fiber-based relay to accommodate the high power beam. The laser unit has been delivered to Subaru office in March 2018 and installed in a testing lab in June 2018. We describe the preliminary design and its requirements and report future plans. This upgrade will not only improve our current adaptive optics system but also be the first step toward the future laser tomography and ground layer adaptive optics system at Subaru Telescope.

A new type of sodium guidestar laser based on semiconductor laser technology is being developed by the astronomy, space, and laser communication communities in Australia and the United States, in partnership with laser manufacturer Arete Associates. Funding has been secured from the Australian Research Council and the Australian National University, with support from academic (UNSW) and industry partners (AAO, GMTO, EOS, Lockheed Martin). The consortium aims to develop a full scale prototype of the Semiconductor Guidestar Laser. The laser, to be delivered in 2019, will be initially installed on the EOS Satellite and Debris Tracking Station 1.8m telescope at Mount Stromlo Observatory where it will be thoroughly tested, on sky and in real operation conditions. This will be the first time that a Laser Guide Star is created in Australian skies. We present the project motivation and objectives, laser development and test plans, and the preliminary test results obtained to date.

We report on the conceptual design study done for the Ground Layer Adaptive Optics system of the ULTIMATE-Subaru project. This is an ambitious instrument project, providing GLAO correction in a square field of view of 14 arcmin on a side, aiming to deliver improved seeing at the near infrared wavelength. Its client instruments are an imager and multi-IFU spectrograph at Cassegrain and a Multi-Object spectrograph at Nasmyth. In this paper, we introduce the ULTIMATE-Subaru project overview and its science case and report the results of the GLAO performance prediction based on the numerical simulation and conceptual design of the wavefront sensor system

As space debris in lower Earth orbits are accumulating, techniques to lower the risk of space debris collisions must be developed. Within the context of the Space Environment Research Centre (SERC), the Australian National University (ANU) is developing an adaptive optics system for tracking and pushing space debris. The strategy is to pre-condition a laser launched from a 1.8 m telescope operated by Electro Optics Systems (EOS) on Mount Stromlo, Canberra and direct it at an object to perturb its orbit. Current progress towards implementing this experiment, which will ensure automated operation between the telescope and the adaptive optics system, will be presented.

We present novel methods for mounting lenses in a pair of instruments that presented challenging optical and mechanical requirements. The first instrument is the replacement Natural Guide Star Sensor (NGS2) for CANOPUS at Gemini South, which incorporates an objective consisting of a stack of six lenses mounted in a common bore. A compliant radial spacer was used to eliminate lens decentre resulting from the additional radial clearance required to accommodate differential thermal strains between the low thermal expansion lenses and a common bore. In the same instrument, tangent contact toroidal spacers were deployed in place of traditional conical spacers to further reduce contact stresses in fragile calcium fluoride lens elements. The toroidal faces were specified with a 10µm profile tolerance to avoid possible edge contact between the spacers and lenses. We investigated milling and turning machining processes for the production of the spacers by comparing their results via Coordinate Measuring Machine (CMM) measurements. In the second instrument, Veloce, built for the Anglo-Australian Telescope, a lens decentre requirement of 40µm led us to develop a simple means of in-situ centring adjustment of the cell mounted lens. Physical testing of the finished instruments verified the performance of each of these methods. NGS2 produced images at the factory acceptance test in which 94% of encircled energy was captured by a single 16um detector pixel, surpassing the specification of 80%. Bench testing of Veloce during assembly showed that the adjustment mechanism allowed centring of the lens over a range of +/- 0.1mm with a precision of 5µm.

Space debris in low Earth orbit (LEO) below 1500 km is becoming an increasing threat to spacecrafts. To manage the threat, we are developing systems to improve the ground-based tracking and imaging of space debris and satellites. We also intend to demonstrate that it is possible to launch a high-power laser that modifies the orbits of the debris. However, atmospheric turbulence makes it necessary to use adaptive optics with such systems. When engaging with objects in LEO, the objects are available only a limited amount of time. During the observation window, the object has to be acquired and performance of all adaptive optics feedback loops optimised. We have implemented a high-level adaptive optics supervision tool to automatise time-consuming tasks related to calibration and performance monitoring. This paper describes in detail the current features of our software.

We report on the design and initial laboratory testing of the Adaptive Optics Imaging (AOI) system. AOI has been developed by the Research School of Astronomy and Astrophysics (RSAA) at the Australian National University (ANU), in partnership with the Space Environment Research Centre (SERC), for imaging satellites and debris in low Earth orbit (LEO) and geostationary orbit (GEO). From AO corrected images we will resolve features greater than 50 cm allowing size, shape and orientation characterisation.

AO systems aim at detecting and correcting for optical distortions induced by atmospheric turbulences. The Gemini South telescope has currently two main AO systems: the Gemini Multi Conjugated AO System GeMS and the Gemini Planet Imager GPI. GeMS is operational and regularly used for science observation delivering close to diffraction limit resolution over a large field of view (85-85 arcsec2). We first review the performance obtained this past year. Then we will go in the details of the strong modifications GeMS is currently having. We are integrating a new laser system in the laser guide star facility module. We are also advancing in the development of the new Natural Guide Star wavefront sensor. We present as well in this paper the preliminary results obtained with our new installed NGS mask that allows us better astrometric precision.

ULTIMATE-Subaru is a next large facility instrument program at Subaru telescope, which will develop 14 x14 arcmin2 wide-field near-infrared imager and multi-object spectrograph with the aid of ground-layer adaptive optics system (GLAO) at the Cassegrain and Nasmyth foci of the telescope in mid 2020s. Our preliminary performance simulation indicates that the GLAO system at Subaru telescope can provide uniform seeing improvement down to FWHM~0.2 arcsec in K band under moderate seeing condition across the field of view up to 20 arcmin in diameter. The main science case of the ULTIMATE-Subaru is a complete census of galaxy evolution from cosmic dawn (z>8) to cosmic noon (z=1-3) with ultradeep, wide-field narrow-band imaging and multi-object spectroscopies of a statistical sample of galaxies especially in K band.

NGS2 is an upgrade for the multi-natural guide star tip-tilt & plate scale wavefront sensor for GeMS (Gemini Multi-Conjugate Adaptive Optics system). It uses a single Nüvü HNü-512 Electron-Multiplied CCD array that spans the entire GeMS wavefront sensor focal plane. Multiple small regions-of-interest are used to enable frame rates up to 800Hz. This set up will improve the optical throughput with respect to the current wavefront sensor, as well as streamline acquisition and allow for distortion compensation.

GeMS, the Gemini South MCAO System, has now been in operation for 3 years with the near infrared imager GSAOI. We first review the performance obtained by the system, the science cases and the current operational model. In the very near future, GeMS will undergo a profound metamorphosis, as we will integrate a new NGS wavefront sensor, replace the current 50W laser with a more robust one and prepare for a new operational model where operations will shift from the mountain to the base facility. Along this major evolution, we are also presenting several improvements on the loop control, calibrations and automatization of this complex system. We discuss here the progress of the different upgrades and what we expect in terms of performance improvements and operational efficiency.

This paper recalls the history of sodium guide star laser systems used in astronomy and space situational awareness adaptive optics, analyzing the impact that sodium laser technology evolution has had on routine telescope operations. While it would not be practical to describe every single sodium guide star laser system developed to date, it is possible to characterize their evolution in broad technology terms. The first generation of sodium lasers used dye laser technology to create the first sodium laser guide stars in Hawaii, California, and Spain in the late 1980s and 1990s. These experimental systems were turned into the first laser guide star facilities to equip mediumto-large diameter adaptive optics telescopes, opening a new era of Laser Guide Star Adaptive Optics (LGS AO)-enabled diffraction-limited imaging from the ground. Although they produced exciting scientific results, these laser guide star facilities were large, power-hungry and messy. In the USA, a second-generation of sodium lasers was developed in the 2000s that used cleaner, yet still large and complex, solid-state laser technology. These are the systems in routine operation at the 8 to 10m-class astronomical telescopes and 4m-class satellite imaging facilities today. Meanwhile in Europe, a third generation of sodium lasers was being developed using inherently compact and efficient fiber laser technology, and resulting in the only commercially available sodium guide star laser system to date. Fiber-based sodium lasers are being or will soon be deployed at three astronomical telescopes and two space surveillance stations. These highly promising systems are still relatively large to install on telescopes and they remain significantly expensive to procure and maintain. We are thus proposing to develop a fourth generation of sodium lasers: based on semiconductor technology, these lasers could provide a definitive solution to the problem of sodium LGS AO laser sources for all astronomy and space situ

The Gemini multiconjugate adaptive optics system (GeMS) at the Gemini South telescope in Cerro Pachón is the first sodium-based multilaser guide star (LGS) adaptive optics system. It uses five LGSs and two deformable mirrors to measure and compensate for

Gender equality in modern societies is a topic that never fails to raise passion and controversy, in spite of the large body of research material and studies currently available to inform the general public and scientists alike. This paper brings the gender equity and equality discussion on the Adaptive Optics community doorstep. Its aim is threefold: (1) Raising awareness about the gender gap in science and astronomy in general, and in Adaptive Optics in particular; (2) Providing a snapshot of real and/or perceived causes for the gender gap existing in science and engineering; and (3) Presenting a range of practical solutions which have been or are being implemented at various institutions in order to bridge this gap and increase female participation at all levels of the scientific enterprise. Actual data will be presented to support aim (1), including existing gender data in science, engineering and astronomy, as well as original data specific to the Adaptive Optics community to be gathered in time for presentation at this conference. (2) will explore the often complex causes converging to explain gender equity issues that are deeply rooted in our male-dominated culture, including: conscious and unconscious gender biases in perceptions and attitudes, worklife balance, n-body problem, fewer numbers of female leaders and role models, etc. Finally, (3) will offer examples of conscious and pro-active gender equity measures which are helping to bring the female to male ratio closer to its desirable 50/50 target in science and astronomy.

Space debris in Low Earth Orbit (LEO) is becoming an increasing threat to satellite and spacecraft. A reliable and cost effective method for detecting possible collisions between orbiting objects is required to prevent an exponential growth in the number

The Australian National University and EOS Space Systems have teamed up to equip the EOS laser space debris tracking station on Mount Stromlo near Canberra, Australia, with sodium Laser Guide Star (LGS) Adaptive Optics (AO). The AO system is used to correct for laser beam degradation caused by the atmospheric turbulence on the upward infrared laser pulse used to illuminate space debris. As a result, the AO-equipped laser tracking station can track smaller and more distant debris. This paper presents the joint ANU/EOS AO Demonstrator LGS facility requirements, architecture, and performance at the time of the conference.