Updated January 7, 2020
The GSAOI web pages have been updated to reflect the recent changes introduced by the replacement of the guiding unit in Canopus. The new guiding unit called Natural Guide Star Next Generation Sensor (NGSNGS or NGS2) has been installed in July 2019. The on-sky characterization of NGS2 have been taken in place in October and December 2019. Results from commissioning show an improvement in sensitivity of about ~2.5 magnitudes, compared to the previous NGS guiding unit. In addition, there is a large improvement in acquisition and offsetting. The NGS2 Canopus WFS (CWFS) limiting magnitudes were verified during the on-sky commissioning blocks. The new limiting magnitudes for the Canopus WFSs are listed in the Canopus WFS limiting magnitudes page. Special attention should be paid to the off-axis Peripheral Wave Front Sensor 1 (PWFS1) star used to compensate the sodium layer variations (see Guiding Options for details). Detailed information about the NGS2 will be added soon in the GeMS CANOPUS Wave Front Sensors (CWFS) web page.
The pages located in the Observation preparations menu have been updated to reflect the changes introduced in the Observing Tool. In particular, the GSAOI OT Details page has been updated with detailed information about the selection of the NGS2 and off-axis PWFS1 stars.
August 26, 2019
In July 2019, the Natural Guide Star Wave Front Sensor (NGSWFS) unit on Canopus has been replaced by a new guiding unit called Natural Guide Star 2 (NGS2). The new WFS is based on a single Electron-Multipled CCD (EMCCD) focal plane array and uses configurable guiding windows (multi-region of interest) to read at rates up to 800 Hz. It is expected that NGS2 will provide a sensitivity gain of more than 2 magnitudes, and improve/solve operational issues related to acquisition and offsetting. The NGS2 CWFS limiting magnitudes will be verified during the on-sky commissioning planned for October 2019. Proposers of new observations with GeMS and GSAOI must continue to use the current Canopus WFS limiting magnitudes. The limiting magnitudes will be update after the NGS2 commissioning run ends.
September 1, 2016
The selection of the ODGW for flexure compensation is not required anymore. Only the Canopus based WFSs (CWFS) must be defined by the proposers of GeMS/GSAOI observations (see Guiding Options web page for details). The MASCOT algorithm implemented in the Observing Tool searches for the best asterism automatically, including the ODGW. Check the instructions in the GSAOI OT Details web page to know how to disable or remove the ODGW from the GSAOI target component.
August 28, 2016
Gemini has released a new software package for GSAOI image; Disco-Stu (DIStortion COrrection and STacking Utility). DISCO-STU is a new standalone software package, written in python, to align and stack GSAOI images that have been reduced with the Gemini GSAOI IRAF package. Additional information and a download link can be found in the Gemini Data Processing Software web page.
March 20, 2015
Another successful GeMS run. The classical nights with observers coming from ANU (Australia) have been very successful. The Gemini staff also collected a lot of good data for the users. As in the previous run, the AO performance was very good and uniform in the entire GSAOI field of view. GeMS observations will be resumed at the end of May (May 27 - June 4, 2015).
January 18, 2015
Despite weather constrains and limitations in laser power, GeMS completed a successful run, delivering lots of great data for users. The AO performance was good and uniform in the entire GSAOI field of view. The resolution varied between 65 mas and 85 mas. During the run, a Large and Long Program has been completed.
December 15, 2014
With the help of an external consultant, our engineers have been able to bring back the laser to a stable 35W level. Classical nights with observers coming from ANU (Australia) and LAM (France) have been very successful. A good progress has been made on the regular queue as well. Good performance was achieved on GSAOI images, with corrected AO FWHM between 70mas and 80mas and uniform PSF across the field of view.
November 20, 2014
Due to a laser issues, the november laser run has been cancelled. The Gemini engineers with the help of an external consultant are working hard to bring back the laser a a stable power.
September 20, 2014
First laser run after the GeMS/GSAOI winter shutdown. During the shutdown, the AO team worked hard to solve the elongated issues seen in the GSAOI images. A comprehensive campaign of optical tests pointed to field stops misalignments in the LGSWFS. Re-alignment of the LGSWFS has consequently been done. The bad weather (clouds and poor seeing) played against us during the entire run (only 6 hours of good GeMS/GSAOI data were obtained). The good news is that despite the bad weather, the re-alignment has successfully tested during the run. We can confirm that elongation problem detected during the first semester of 2014 has gone.
June 20, 2014
The June 2014 (03 - 12) laser run was largely affected by the bad weather at Gemini South. The bad conditions and snow prevented the Gemini staff to observe with GeMS/GSAOI or any other instrument. The telescope remained closed the whole run. GeMS and GSAOI have been removed from the ISS. The laser observations will be resumed in September 2014.
April 17, 2014
The Gemini South laser is back in use after repair work by Gemini staff and outside contractors. A successfully GeMS/GSAOI run just finished (April 8 - April 16, 2014). Good weather conditions allow to observe several science programs during this run. A new observing block with GeMS/GSAOI is expected to start May 21, 2014
February 21, 2014 - March GeMS run Cancelled
The Gemini South laser suffered a fault towards the end of the last GeMS run in February. The laser power has been lost to a level that prohibits useful science. Unfortunately, despite all the efforts of the laser team, we were not able to recover the laser during the run. The problem has been identified and a plan is under development to recover, which involves replacement of key hardware parts and realignment of the system. Internal and external specialists will collaborate to complete this work and return the laser to the level required to do science. Unfortunately, due to complexity and scheduling constraints, we have determined that this work can not be completed in time for the March run. Therefore, we have no other option than to cancel the upcoming GeMS run in March. Canceling this run will give the laser team a larger window to work together and recover the system to a good state for the April GeMS run.
November 06, 2013
The nights in the September GeMS/GSAOI run were plagued by bad weather, telescope issues and GeMS-related problems. The October run also suffered from poor weather, but the GeMS technical problems were largely addressed. During the October, only one science observation was executed. With most of the GeMS technical issues identified and fixed, GeMS/GSAOI is ready for science use in the December run (Dec 14 - Dec 20).
August 28, 2013
GSAOI is installed back on the ISS (port 1) after three month of a general engineering maintenance. During this period, the motors of Filter Wheel 1 and 2, and the motor of the utility wheel, where replaced and optic was cleaned. After a successfully shutdown and a general GSAOI check, the instrument is ready to continue to deliver science data
July 2, 2013
The Gemini Observatory has been released a set of GeMS/GSAOI commissioning and System Verification science observations. The Gemini Observatory press release includes information about seven ultrasharp, large-field images observed with GeMS/GSAOI. The images are available here
June 25, 2013
Data taken as part of GSAOI System Verification (SV) are now public. The users can retrieve the SV data directly from the Gemini Science Archive following this link
7 - 13 June 2013
A very successfully semester for GeMS/GSAOI has ended. During the period between February 2013 and June 2013, ~90% of the SV programs and eleven 2013A queue programs were completed. GSAOI has been removed from the telescope to the Instrument Laboratory for a general engineering maintenance. The observations with GeMS/GSAOI will be in September 2013.
March 31, 2013
The GeMS/GSAOI SV observations were successfully completed. Of the thirteen approved programs, (eight in Band 1 and five in Band 2), eleven programs were completed, one was 50% completed and one was not observed because the guide stars were too faint. Also, we continue with the observation of 2013A queue programs.
18 - 22 February 2013
First GeMS/GSAOI run in queue. During the run, we completed three more SV programs and started to observe some of the 2013A queue programs.
18 - 22 February 2013
First GeMS/GSAOI run in queue. During the run, we completed three more SV programs and started to observe some of the 2013A queue programs.
25 January 2013 - 2 February 2013
14th GeMS/GSAOI commissioning run. During this run, we have completed six SV programs and made good progress on another three. In optimal seeing, the first diffraction ring has been visible on point sources, and even in poor seeing, the AO correction is excellent. The GSAOI commissioning is almost completed.
26 December 2012 - 1 January 2013
13th GeMS/GSAOI commissioning run. The run was focused on the optimization of GeMS, complete pending GSAOI commissioning tasks and start the observations of the approved SV programs. Very successfully run. See http://www.gemini.edu/node/11925 for details about the Orion bullet image obtained with GeMS/GSAOI. In addition, some of the SV programs were started.
15 December 2012
Engineers have been working hard to fix the problem with the filter wheel 1 on GSAOI. After several days of work and motor replacement, the GSAOI filter wheel 1 come back. The filter wheel 1 was extensively tested with no failures. The instrument is ready for the next GeMS/GSAOI commissioning run.
3 - 9 November 2012
12th GeMS/GSAOI commissioning run. Problems with the filter wheel 1 prevented us to use some of the broad band filters in GSAOI. Unfortunately the poor weather, the problem with the filter wheel 1 and the low laser power prevented us to complete of the commissioning tasks.
14 October 2012
GeMS/GSAOI System Verification proposals produced some 29 applications, from which 13 were selected. We received about three times as many proposals as we required. The final selection can be see at http://www.gemini.edu/sciops/instruments/gsaoi/systemverification/sciops/instruments/gsaoi/system-verification/accepted-programs-and-status.
1 September 2012
GeMS/GSAOI is offering to the community for semester 2013A. The instruments are offering in a shared-risk mode for a total of around 100 hours.
27 August 2012
GeMS/GSAOI System Verification (SV) call for proposal has been released. Approximately 60 hours of SV time is available in the 2012B semester. We expect to observe SV programs between December 1, 2012 and January 31, 2013. See
02 May 2012
GSAOI is removed from the telescope to the Instrument Laboratory for a general engineering maintenance. GSAOI commissioning will be resumed at the end of October 2012.
26 - 30 April 2012
11th GeMS/GSAOI commissioning run. The poor weather was a major issue during the commissioning run. Most of the nights were lost due to poor weather, however useful data were obtained to complete some of the high priority GSAOI commissioning tasks.
9 - 15 April 2012
10th GeMS/GSAOI commissioning run. Most of the nights were lost due to poor weather that prevented to complete the planned GSAOI commissioning tasks for this period.
20 March 2012
Call for community commissioning targets released. See http://www.gemini.edu/node/11800 for details.
8 - 15 March 2012
9th GeMS/GSAOI commissioning run. Unfortunately, a cooling problem with GSAOI prevented the use of the instrument during the commissioning run. The cooling problem in GSAOI didn't stop the GeMS commissioning to continue. The GeMS team used GMOS for commissioning/verification purposes and to demonstrate the capability of GeMS below 1 µm.
4 March 2012
GSAOI is installed back at the telescope after the replacement of the entrance window. The instrument is cold and ready for the next commissioning run.
21 February 2012
GSAOI is removed from the telescope to the Instrument Laboratory. The instrument will be warmed up in order to replace the damaged entrance window, which lost the coating in the central region of the window. The work will take 10 days.
6 - 14 February 2012
8th GeMS/GSAOI commissioning run. During this commissioning run we concentrated in the characterize of the new Natural Guide Star Wave Front Sensor Probe 1 installed in Canopus. The team completed the Canopus and ODGW mapping. The variable seeing was an issue during the run. Images of a blank sky region were obtained to calculate the background contribution in all filters. Continue to monitor the system throughput using different filters. We have discovered a problem with the coating in the GSAOI entrance window. This problem can affect the system throughput. Analysis in on-going to evaluate how muh sensitivity we are loosing. Obtained a good set of engineering images on nice targets.
6 - 12 Jan 2012
7th GeMS/GSAOI commissioning run. The GSAOI science team completed the detector characterization (read noise and gain determination, non-linearity correction, detectors linearity), derived a final values for the Instrument Alignment Angle and WCS solutions, obtained data for throughput measurements for different filters and exercised the acquisition procedures for different type of targets. A very successful run.
12 - 20 Dec 2011
A very successful 7th GeMS commissioning run with GSAOI installed on port 1 of the ISS. The run was focused on the optimization of GeMS and to demonstrate the potential of the system. See http://www.gemini.edu/node/11715 for details about the first light ultra-sharp wide field image obtained with GeMS and GSAOI. At the same time, the GSAOI science team continued to make a good progress in several instrument related commissioning tasks.
27 Nov 2011
GSAOI is installed back at the telescope after a five-month of maintenance. During this period, the detector controller and component controller software were updated, and the GSAOI Environmental Window was cleaned from dust accidentally accumulated after the instrument was installed on port 5 of the ISS in January 2011.
12 - 20 Nov 2011
6th GeMS commissioning run. GSAOI is planned to be installed back on the ISS at the end of November.
3 June 2011
GSAOI is removed from the telescope to the Instrument Laboratory for a general engineering maintenance. GSAOI commissioning will be resumed at the end of 2011.
17 - 22 May 2011
5th GeMS/GSAOI commissioning run. Most of the nights were lost due to poor weather that prevented to complete the planned GSAOI commissioning tasks for this period.
16 - 22 April 2011
4th GeMS/GSAOI commissioning run with the Laser fully operational. The GSAOI science team continues to make a good progress in several commissioning tasks, like on-sky orientation, WCS, etc. On April 19, 2011, the engineering first light image is obtained with GeMS and GSAOI (see the press release).
21 - 27 March 2011
3rd GeMS/GSAOI commissioning run with the Laser fully operational. The visiting ANU team and the GSAOI science team made a good progress in several GSAOI pre-commissioning tasks. The GeMS team were able to close the loop with the laser and the NGS tip tilt.
20 - 27 February 2011
2nd GeMS commissioning run with GSAOI installed on port 5 of the ISS. At this stage, GSAOI is used only to characterize the Laser and the AO bench (Canopus).
13 January 2011
GSAOI was installed on port 5 of the ISS on Gemini South. The visiting ANU team and the GSAOI science team are currently completing checks to ensure the installation was successful.
GSAOI installation on Gemini South Observatory (January 13, 2011)
9 January 2011
An Australia National University (ANU) team consisting of Peter Young and Matthew Doolan arrive at Gemini South in preparation for the installation of GSAOI on the telescope
16 August 2010
An Australia National University (ANU) team consisting of Peter McGregor (PI), Peter Young, Matthew Doolan, and Jan van Harmelen visited Gemini South for a week to provide advance training to the Gemini South GSAOI science and engineering teams. The visit was successful. Plans for installation and commissioning are progressing for early 2011.