We report on a joint European Science Foundation-ESA “Forward Look” project called TECHBREAK aimed at identifying technological breakthroughs for space originating in the non-space sector. We show how some of the technologies highlighted may impact future space programmes, in particular novel ideas to enable future long-life large telescopes to be deployed. The study’s final report was presented to ESA’s High level Science Policy Advisory Committee (HISPAC) in late 2014. The goals of the study were to forecast the development of breakthrough technologies to enable novel space missions in the 2030-2050 timeframe, and to identify related partnerships through synergies with non-space specialists. It was not prepared to serve as a definitive guide for very specific technologies to be developed for future space missions, but to inform on and flag up the main developments in various technological and scientific areas outside space that may hold promise for use in the space domain. The report does this by identifying the current status of research for each domain, asserting the development horizon for each technology and providing some entry points, in the form of key European experts and institutions with knowledge of the domain. The identification of problems and solutions specific to the space area led us to focus the discussion around the concept of “Overwhelming Drivers” for space research and exploration, i.e. long-term goals that can be transposed into technological development goals. Two of these overwhelming drivers are directly relevant to ambitious future telescope projects, and we will show how some of the technologies we identified such as biomimetic structures, nanophotonics, novel materials and additive manufacturing could be combined to enable revolutionary new concepts for space telescopes.
Two teams of scientists and engineers at Max Planck Institut fuer Extraterrestrische Physik and at the European Southern Observatory have joined forces to design, build and install the Laser Guide Star Facility for the VLT.
The Laser Guide Star Facility has now been completed and installed on the VLT Yepun telescope at Cerro Paranal. In this paper we report on the first light and first results from the Commissioning of the LGSF.
We report on the ongoing VLT Laser Guide Star Facility project, which will allow the ESO UT4 telescope to produce an artificial reference star for the Adaptive Optics systems NAOS-CONICA and SINFONI. A custom developed dye laser producing >10W CW at 589nm is installed on-board of the UT4 telescope, then relayed by means of a single mode optical fiber behind the secondary mirror, where a 500mm diameter lightweight, f/1 launch telescope is projecting the laser beam at 90 km altitude.
We described the design tradeoffs and provide some details of the chosen subsystems. This paper is an update including subsystems results, to be read together with our previous paper on LGSF design description.
We report in this paper on the design and progress of the ESO Laser Guide Star Facility. The project will create a user facility embedded in UT4, to produce in the Earth's Mesosphere Laser Guide Stars, which extend the sky coverage of Adaptive Optics systems on the VLT UT4 telescope. Embedded into the project are provisions for multiple LGS to cope with second generation MCAO instruments.
During the design phase of the ESO Very Large Telescope considerably emphasis was placed on providing the means of controlling and monitoring thermal and wind disturbances. Today, about one year after the start of operation of the first Unit Telescope, much has been learned about the behavior of the telescope, and also about the optimum control strategies to reduce such disturbances. This paper outlines the current strategy for the control of environmental disturbances and discuses some of the lessons that have been learned.
Each of the 12 Nasmyth and Cassegrain foci of the ESO very large telescope (VLT) will be equipped with an 'adapter/rotator' which provides the mechanical interface for the science instruments and several key functions for the control of the telescope, namely a CCD sensor for acquisition and guiding, and a separate CCD sensor as wavefront sensor for the active optics control system. This paper describes the origins and concept for the VLT adapter/rotators, and the principal design drivers and constraints.
An important contributory factor to the overall quality of the images obtained with the VLT are random tilt errors caused by wind buffeting and the atmosphere. The techniques and strategy adopted to overcome these errors are described. Image position errors caused by wind buffeting are minimized, as far as possible, by optimizing the configuration of the telescope enclosure for the prevailing wind and observing conditions. Residual tilt errors are reduced to acceptable limits by the use of a secondary mirror tilt-tip mechanism in conjunction with the telescope axis control system. In situations where the ratio of D/r0 is small, atmospheric tilt can contribute the dominant source of tilt error. In these cases the same correction procedure using the secondary mirror can even improve the image quality beyond the long integration atmospheric limit. Possible control schemes and results of simulations are presented to demonstrate the effectiveness of these solutions. The limitations of the techniques are discussed as well as their value compared to a full wavefront correction of the VLT adaptive optics system.