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Rubin Observatory Response to Recent Events

**Versión en Español mas abajo**

Dear Colleagues,

In the past couple of weeks, we have witnessed a number of disturbing events in the U.S., on top of the COVID-19 pandemic that we have all been coping with for months now. The murders of George Floyd and Ahmaud Arbery have made it unbearably apparent that racial injustice is very much a reality in this country, and that it continues to plague the lives of people of color.

The unrest in the streets is not unexpected, given the systemic and long term inequities many of you have had to endure. This is an unconscionable situation. We stand by you, and we want to convey our empathy if you are fearful for your own safety in light of the current events.

Vera C. Rubin Observatory – Impact of Satellite Constellations

Revised May 19, 2020

Executive Summary

  • Simulations of the Rubin Observatory Legacy Survey of Space and Time (LSST) observing cadence and the full 42,000 SpaceX satellite constellation show that as many as 30% of all LSST images would contain at least one satellite trail.
  • Nearly every LSST image taken during twilight would be affected by at least one satellite trail.
  • Measurements of the brightness of the current LEO satellites indicate that trails would cause residual artifacts in the reduced data, if no mitigations are made.
  • SpaceX is on track to darken their Starlink satellites to 7th mag, which would enable removal of artifacts in LSST images.

ComCam Progress in La Serena

May 5, 2020 - The Rubin Observatory Commissioning Camera (ComCam) shipped from Tucson, AZ, on March 16th and arrived safely in Chile in early April. Because of the summit construction shutdown (due to safety concerns about the COVID-19 pandemic), the ComCam team set up an instrument lab at the AURA Base Facility in La Serena in order to confirm that ComCam had arrived undamaged. There was some extra space in the Base Facility Data Center server room for the temporary lab—this solution ensured plenty of isolated space for working, but also made network connectivity to the ComCam and other observatory servers relatively straightforward.

Data Facility Opportunity Update

April 30, 2020 -  On April 22nd, the US Department of Energy (DOE) announced to the Rubin Operations team that DOE, in coordination with the National Science Foundation (NSF), will put out a Financial Opportunity Announcement (FOA) for the US Data Facility (USDF) for Rubin Operations. During operations, the USDF will operate and maintain the systems which are being developed during construction to produce and provide Rubin Observatory scientific data products to its community.

The FOA process would:

Summit Inspections

April 24, 2020 - It's been just over a month since construction on Rubin Observatory stopped because of concerns over the COVID-19 pandemic, and although we don't have a definite date when activities can resume, the Project team is busy making plans for how that can safely happen when it's time. In the meantime, since the shutdown began we've been sending small teams (using all the appropriate precautions and safety measures) to Cerro Pachón about every two weeks to inspect the facilities and equipment on the summit and perform necessary maintenance tasks. The workers travel to the summit in individual vehicles, and only those whose expertise is essential to completing that day's list of pre-arranged tasks make the trip.

COVID-19 Construction Shutdown

The COVID-19 pandemic is having a significant impact on Rubin Observatory construction activities. As a preventative measure, construction activities on Cerro Pachón were shut down on Friday, March 20th, and the site was secured as safely as possible given the incomplete condition of the facility. SLAC National Accelerator Laboratory also closed, and work on the Camera has ceased.

All Rubin Observatory staff are now teleworking, and progress is being made in software development and a number of other areas. When safety permits, staff will be able to return to the summit and construction will ramp up as quickly as is feasible. Project leadership will work with our funding agencies, the National Science Foundation (NSF) and the US Department of Energy (DOE), to evaluate the impact on the construction timeline.

Answers to frequently asked questions about the impact of the COVID-19 pandemic on Rubin Observatory, as well as the latest updates to this evolving situation, are available here.


Rubin meets Euclid: towards a joint Derived Data Products Working Group

Informal joint public statement.

We are pleased to share with you some news on the interaction between Vera C. Rubin Observatory and the Euclid Consortium. We believe, and hope you will agree, that both the Rubin Observatory and Euclid science communities would benefit from the Rubin Observatory Legacy Survey of Space and Time (LSST) and Euclid datasets being jointly processed to produce shared “derived data products” (DDPs). To make progress towards this goal we are establishing a joint DDP working group, the DDP-WG, that will recommend a science-driven initial set of DDPs which would be shared promptly and simultaneously with both the Euclid Consortium and all Rubin Observatory LSST data rights holders for scientific use, in a way that protects the unique science of each collaboration and respects the data policies of each collaboration. We expect the DDP-WG will take broad input from both science communities in establishing the recommended DDPs.

While the DDP-WG will not be the group that will decide who makes the DDPs, where they are made, how they are made, or what funding mechanism will pay for that effort, the idea is that this initial set of DDPs, if approved, would form the basis of a Letter of Intent signed by both Rubin Observatory and Euclid leadership to actually create those DDPs. The DDP-WG would then remain a science-focused, standing committee that would recommend further DDPs as both the Euclid and LSST surveys progress.

Given the data and publication policies of both Rubin Observatory and the Euclid Consortium, a collaborative agreement between the two groups is the only way that such joint derived data products can be made and then shared back to either of the two groups for publication during the respective proprietary periods. There is still much work to be done to find a set of DDPs that are mutually and equally beneficial to both communities - but we are confident we can set up a DDP-WG to succeed at this task.

Our next steps are to appoint and charge this working group; we have in mind asking it to hold a virtual workshop within the next 6 months in order to help collect the input it will need from both science communities. This workshop would be open to the larger Euclid and Rubin Observatory communities, not just the DDP-WG. Stay tuned for more information on, and from, the DDP-WG as it gets started, and please don’t hesitate to get in touch with comments, questions, and suggestions, either in the public comments on community or privately, at

Yours in wide-field survey astronomy,

Bob, Yannick, Phil & Jason


First Images with AuxTel Spectrograph

February 24, 2020 - At the end of January, the Rubin Observatory Auxiliary Telescope spectrograph made its first observations of astronomical objects on Cerro Pachón! These "first light" images represent real, usable data for Rubin Observatory, and are the results of years of hard work by many people from the Camera, Data Management, and Telescope & Site subsystems, as well as IT and Systems Engineering. The images also represent a milestone for system integration and commissioning for the whole Rubin Observatory construction project–because the Rubin Observatory Simonyi Survey Telescope will use essentially the same software system, the work on the Auxiliary Telescope and all the knowledge gained during the integration process will be critical when it's time to combine the software and hardware for Rubin Observatory.

The Auxiliary Telescope, or AuxTel, is a part of Rubin Observatory and sits on a hilltop close to the main facility. It uses a spectrograph, which was installed in January, to study the effect of the atmosphere on the light coming from distant stars and galaxies. By using these measurements we will be able to improve the quality of the data from the main telescope. This has the effect of eliminating one source of error in our measurements, enabling more and better science.

What's in the atmosphere that will affect Rubin Observatory images? Lots of things are possible, including water, ozone, and aerosols like dust and sea salt. Even ash from far-away forest fires, like those burning in Australia this winter, can be found in the atmosphere over Chile. The Rubin Observatory team will do a detailed study of what's present above Cerro Pachón, and how often conditions change. AuxTel isn't capable of moving as quickly as the Rubin Observatory Simonyi Survey Telescope, but how hard AuxTel will have to work to coordinate its movements with past and future positions of the main telescope will depend on whether conditions in the atmosphere tend to be stable or constantly changing.

On the first night of on-sky observations with the spectrograph, the team started by pointing at the Orion Nebula to make sure that there would be stars and structure in the resulting images. Below on the left is the raw image, without any processing, as it first appeared on the screen, and below right is a roughly focused, longer exposure. These images proved that the telescope and instrument were working well, so the team moved to more isolated stars for more detailed diagnoses, taking dispersed images throughout the night (resulting in the images at the top of the page).

Even though conditions on this first night weren't ideal, the team is excited about this successful test of the AuxTel system, they are now focusing on the fine-tuning that will improve the quality and usefulness of the data. Congratulations to the AuxTel team!

Image credits: Rubin Obs./NSF/AURA






Coming Soon - First ComCam Image

February 6, 2020 - The Commissioning Camera for the Vera C. Rubin Observatory is still in the lab at the Rubin Observatory Project Office in Tucson, AZ, where it arrived in June 2019. But it won't be there much longer; it’s undergoing a near-final phase of testing before being packed for shipping to Chile (currently scheduled for late February). The Commissioning Camera, or ComCam, is a much smaller version of the Rubin Observatory LSST Camera (LSSTCam) with about 1/20 of the collecting area that will be used to test the different systems that will interact with the full science camera during Rubin Observatory Operations. 

Electro-optical testing of ComCam was conducted in the fall of 2019, and now software testing is underway. In mid-January, 2020, the ComCam optical system was successfully integrated with the “quad box,” which contains the utilities necessary to operate the camera. An additional set of utilities, currently at SLAC National Accelerator Laboratory, will be added once the instrument is in Chile. This will constitute the “Refrigeration Pathfinder, which will allow ComCam to condition and demonstrate the custom-made refrigeration system on the telescope before LSSTCam is installed. Next, the structure will be integrated with a mass simulator, which is currently being fabricated in the instrumentation shop at the Rubin Observatory Project Office in Tucson. The mass simulator will allow ComCam to be mechanically integrated with the telescope and used for testing on Cerro Pachón.

The final milestone that must be achieved before the camera is readied for shipping is a full execution of the hardware and software interface system—basically a rehearsal of every step involved in producing an image with ComCam on sky. From the control software that allows for coordinated operation of the camera, to the pipelines that read out the camera data and send it to the National Center for Supercomputing Applications (NCSA) in Illinois for processing; the whole procedure must be tested and verified in Tucson before the camera is packed for shipping. The mass simulator will go to Chile by ship, but the more delicate pieces will travel by air. They will be accompanied by sensors that monitor environmental factors like temperature, humidity, and motion, and the data collected will be used to plan the shipment of LSSTCam from SLAC to Chile in 2021.

Watch this space—we plan to share one of the first images produced by ComCam before the camera ships. It won’t be an image of the sky, but it will show that the camera is ready for action!


First national US observatory to be named after a woman!

It was announced today that the upcoming Large Synoptic Survey Telescope (LSST), which will conduct a vast astronomical survey for unprecedented discovery of the deep and dynamic Universe, will now be named the NSF (National Science Foundation) Vera C. Rubin Observatory (Rubin Observatory). The announcement was made today by Ralph Gaume, Director of the NSF Division of Astronomical Sciences; Kathy Turner, DOE (Department of Energy) Office of High Energy Physics program manager; and Steve Kahn, LSST Director during the LSST Open House at the 235th American Astronomical Society meeting in Honolulu, Hawai’i, USA. The construction and operations of the Rubin Observatory and the DOE LSST Camera is a U.S.


Financial support for LSST comes from the National Science Foundation (NSF) through Cooperative Agreement No. 1258333, the Department of Energy (DOE) Office of Science under Contract No. DE-AC02-76SF00515, and private funding raised by the LSST Corporation. The NSF-funded LSST Project Office for construction was established as an operating center under management of the Association of Universities for Research in Astronomy (AURA).  The DOE-funded effort to build the LSST camera is managed by the SLAC National Accelerator Laboratory (SLAC).
The National Science Foundation (NSF) is an independent federal agency created by Congress in 1950 to promote the progress of science. NSF supports basic research and people to create knowledge that transforms the future.
NSF and DOE will continue to support LSST in its Operations phase. They will also provide support for scientific research with LSST data.

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