GeMS, the Gemini Laser Guide Star Multi-Conjugate Adaptive Optics facility system, has seen first light in December 2011, and has already produced images with H band Strehl ratio in excess of 35% over fields of view of 85x85 arcsec, fulfilling the MCAO promise. In this paper, we report on these early results, analyze trends in performance, and concentrate on key or novel aspects of the system, like centroid gain estimation, on-sky non common path aberration estimation. We also present the first astrometric analysis, showing very encouraging results.
The telescope development projects of the 1990's produced a set of capable 8-10m telescopes that are now in operations
across the northern and southern hemispheres. This was the first generation of telescopes to benefit from carefully
engineered software systems, yet several years of 8m operations have revealed weaknesses in a common architecture
employed by many of them. Today engineers are working on the next generation of telescopes, the extremely large
telescopes (ELTs), along with their software systems. It is our view that many of the fundamental assumptions about
how software systems for 8-m class large telescopes should be constructed are not optimal for the next generation of
extremely large telescopes. In fact, these ideas may constrain the solution space and result in overly complex software
and increased development costs. This paper points out issues with current architecture solutions and how they impact
the software needed for extremely large telescopes. It then provides the outline of a new approach for the design of the
software running at the telescope that is targeted towards the development issues of ELTs and large telescope operations.
Gemini Observatory is using a new approach with instrument software that takes advantage of the strengths of our
instrument builders and at the same time better supports our own operational needs. A lightweight software library in
conjunction with modern agile software development methodologies is being used to ameliorate the problems
encountered with the development of the first and second-generation Gemini instruments.
Over the last two years, Gemini and the team constructing the software for the Gemini Planet Imager (GPI) have been
using an agile development process to implement the Gemini Instrument Application Interface (GIAPI) and the highlevel
control software for the GPI instrument. The GPI is being tested and exercised with the GIAPI, and this has
allowed us to perform early end-to-end testing of the instrument software. Early in 2009 for the first time in our
development history, we were able to move instrument mechanisms with Gemini software during early instrument
construction. As a result of this approach, we discovered and fixed software interface issues between Gemini and GPI.
Resolving these problems at this stage is simpler and less expensive than when the full instrument is completed.
GPI is currently approaching its integration and testing phase, which will occur in 2010. We expect that utilizing this
new approach will yield a more robust software implementation resulting in smoother instrument integration, testing,
and commissioning phases. In this paper we describe the key points of our approach and results of applying the new
instrument API approach together with agile development methodologies. The paper concludes with lessons learned and
suggestions for adapting agile approaches in other astronomy development projects.
The key to a successful observing experience at Gemini is a well-prepared science program. The astronomer uses a
software application called the Gemini Observing Tool (OT) to fill in the specifics of instrument and telescope
configuration during the Phase 2 process. This task involves knowing several details about the Gemini instruments as
well as particularities of the telescope and the best way to observe with them. Unfortunately, reviewing these programs
can be tedious and error prone. Failure to catch a simple misconfiguration could lead to suboptimal science results or
even lost time at the telescope.
As part of an effort to make it easier for investigators to define the details of their programs and for the National Gemini
Offices and Gemini contact scientists to check and validate them, we have included an automatic program-checking
engine in the OT. The "Phase 2 Checker" continually examines the science program configuration as edits are made,
finds significant problems, and reports them to the user along with suggested corrections.
Since its introduction in the 2007B semester release of the Observing Tool, this feature has been very well received by
the community. This paper describes the software (infrastructure and user interface) that supports the Phase 2 Checker,
results of validating new and existing science programs, and future improvements we are currently considering.
The Gemini Observatories primarily operate a multi-instrument queue, with observers selecting observations that are best suited to weather and seeing conditions. Queue operations give higher ranked programs a greater chance for completion than lower ranked programs requesting the same conditions and instrument configuration. Queue observing naturally lends itself to Target of Opportunity (ToO) support since the time required to switch between programs and instruments is very short, and the staff observer is trained to operate all the available instruments and modes. Gemini Observatory has supported pre-approved ToO programs since beginning queue operations, and has implemented a rapid (less than 15 minutes response time) ToO mode since 2005. We discuss the ToO procedures, the statistics of 2+ years of rapid ToOs at Gemini North Observatory, the science that this important mode has enabled, and some recent software modifications which have improved both standard and rapid ToO support in the Gemini Observing Tool.
Gamma-ray bursts and other targets of opportunity require a quick response by observers to maximize the significance of observations. Because of this need for quickness, these types of observations are often observed at smaller facilities where observers and institutions have more freedom to respond to serendipitous events. The two Gemini 8-m telescopes have a well-developed workflow for queue observing that allows investigators to be involved in their science program throughout its lifecycle. To coincide with the startup of the Swift Gamma Ray Burst Explorer orbiting observatory in late 2004, the Gemini observing policies, workflow, and observing tools were enhanced to allow investigators to participate in target of opportunity programs. This paper describes how target of opportunity has been integrated into Gemini operations to allow investigators to trigger observations at the Gemini telescopes within minutes of an event.
At Gemini, support for observers during Phase 2 is a collaborative effort among individuals spread across four continents at many institutions. Short Phase 2 preparation periods necessitate close communication between observers and support personnel. Email alone has not been an adequate solution. For the 2003B semester, the Gemini Observing Tool has been extended to allow off-site investigators and national project office support personnel to directly access the science program database. The observer is able to keep up to date with changes by accessing his program at any time. Email notifications are generated automatically when activities occur in the science program lifecycle. This paper will give an overview of how this system, based upon Java and freely available open source software, provides these new capabilities.
Processing astronomical images is an inherently resource intensive procedure that is typically time consuming as well. At the same time, first order reductions are particularly important during the observing process since they can provide key quality assessment information. To resolve this conflict, the Online Data Processing (OLDP) system being commissioned at the Gemini Observatory automatically maps reduction sequences onto a cluster of servers during observing, taking advantage of available concurrency where possible. The user constructs a visual representation of the sequence for an observation using the Gemini Observing Tool. No constraints are placed upon the series of steps that comprise the sequence. At runtime, the OLDP reads the reduction sequence from the Observing Database and splits it into smaller pieces for simultaneous execution on the cluster. Recipe steps can be implemented in IRAF, shell scripts, or Java, and other types can be plugged into the architecture without modifying the core of the code base. This paper will introduce the Gemini OLDP and demonstrate how it utilizes modern infrastructure technology like Jini and JavaSpaces to achieve its goals.
Today's astronomers may use the telescopes and instruments of many observatories to execute their science observations. Discovering the distributed resources that are available is time consuming and error prone because astronomers must manually take facility information and match it to the needs of their science observations. While Phase 1 and Phase 2 of the
proposal process are well supported by a wide variety of software tools, the initial phase of discovering what resources are available, Phase 0, suffers from a lack of software support. This paper describes and proposes the creation of a Phase 0 Network to fill this void. The network is built upon peer-to-peer (P2P) technology, showing that this new approach to distributed computing has viable uses in astronomy.
Construction of the first Gemini 8-m telescope is well underway. The software that provides the user interface and high-level control of the observatory, the observatory control system (OCS), is also proceeding on track. The OCS provides tools that assist the astronomer from the proposal submission phase through planning, observation execution, and data review. A capable and flexible software infrastructure is required to support this comprehensive approach. New software technologies and industry standards have played a large part in the implementation of this infrastructure. For instance, the use of CORBA has provided many benefits in the software including object distribution, an interface definition language, and implementation language independence. In this paper, we describe the infrastructure of the OCS that supports observation planning and execution. Important software decisions and interfaces that allow Internet access and the ability to substitute alternate implementations easily are discussed as a model for other similar projects.
The new 8-meter class telescopes represent large investments by the development communities. This means that these telescopes must be operated efficiently to provide the best possible return on these investments and a great deal of effort has been made to provide control software that supports effective use of the telescopes. However, efficient use must be more than just keeping the telescopes operating; it is important that observers be provided tools that enable them work effectively. The Gemini 8 m Telescopes have developed a strategy for helping astronomers plan observations through the design of science programs. While there are a number of unique aspects to this strategy, this paper focuses on the methods used as the foundation for connecting astronomers to the facilities of the observatories during the design of science programs. The methods under development take advantage of emerging Internet technologies to help reduce the maintenance issues normally associated with supporting remote sites, while freeing users from many of the performance problems associated with web-based solutions.