Vera C. Rubin Observatory

Vera C. Rubin Observatory

Rendering of completed LSST
Alternative names	LSST
Named after	Vera Rubin
Location(s)	Elqui Province, Coquimbo Region, Chile
Coordinates	30°14′40.7″S70°44′57.9″W / 30.244639°S 70.749417°W / -30.244639; -70.749417 [1] [3] [4]
Organization	Large Synoptic Survey Telescope Corporation
Observatory code	X05
Altitude	2,663 m (8,737 ft), top of pier [1] [5]
Wavelength	320–1060 nm [6]
First light	Expected in January 2025 [7]
Telescope style	Three-mirror anastigmat, Paul-Baker / Mersenne-Schmidt wide-angle [8]
Diameter	8.417 m (27.6 ft) physical 8.360 m (27.4 ft) optical 5.116 m (16.8 ft) inner [9] [10]
Secondary diameter	3.420 m (1.800 m inner) [9]
Tertiary diameter	5.016 m (1.100 m inner) [9] [10]
Angular resolution	0.7″ median seeing limit 0.2″ pixel size [6]
Collecting area	35 square meters (376.7 sq ft) [6]
Focal length	10.31 m (f/1.23) overall 9.9175 m (f/1.186) primary
Mounting	altazimuth mount
Website	http://rubinobservatory.org/
Location of Vera C. Rubin Observatory
Related media on Commons

The Vera C. Rubin Observatory, formerly known as the Large Synoptic Survey Telescope (LSST), is an astronomical observatory under construction in Chile. Its main task will be carrying out a synoptic astronomical survey, the Legacy Survey of Space and Time. ^{[11] [12]} The word "synoptic" is derived from the Greek words σύν (syn 'together') and ὄψις (opsis 'view'), and describes observations that give a broad view of a subject at a particular time. The observatory is located on the El Peñón peak of Cerro Pachón, a 2,682-meter-high (8,799 ft) mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes. ^[13] The LSST Base Facility is located about 100 kilometres (62 miles) away from the observatory by road, in the city of La Serena. The observatory is named for Vera Rubin, an American astronomer who pioneered discoveries about galaxy rotation rates.

The Rubin Observatory will house the Simonyi Survey Telescope, ^[14] a wide-field reflecting telescope with an 8.4-meter primary mirror ^{[9] [10]} that will photograph the entire available sky every few nights. ^[15] The telescope uses a novel three-mirror design, a variant of three-mirror anastigmat, which allows a compact telescope to deliver sharp images over a very wide 3.5-degree-diameter field of view. Images will be recorded by a 3.2-gigapixel charge-coupled device imaging (CCD) camera, the largest digital camera ever constructed. ^[16]

The LSST was proposed in 2001, and construction of the mirror began (with private funds) in 2007. LSST then became the top-ranked large ground-based project in the 2010 Astrophysics Decadal Survey, and the project officially began construction on 1 August 2014, when the United States National Science Foundation (NSF) authorized the FY2014 portion ($27.5 million) of its construction budget. ^[17] Funding comes from the NSF, the United States Department of Energy, and private funding raised by the dedicated international non-profit organization, the LSST Discovery Alliance. Operations are under the management of the Association of Universities for Research in Astronomy (AURA). ^[18] The total construction cost is expected to be about $680 million. ^[19]

Site construction began on 14 April 2015 with the ceremonial laying of the first stone. ^{[20] [21]} The first on-sky observations with the engineering camera occurred on 24 October 2024 ^[22] , while system first light is expected in January 2025 and full survey operations are aimed to begin in August 2025, due to COVID-related schedule delays. ^[23] LSST data is scheduled to become fully public after two years. ^[24]

Name

Vera C. Rubin Observatory and the Milky Way

In June 2019, the renaming of the observatory from the Large Synoptic Survey Telescope (LSST) to the Vera C. Rubin Observatory was initiated by United States Representative Eddie Bernice Johnson and Jenniffer González-Colón. ^[25] The renaming was enacted into United States law on 20 December 2019, ^[26] and announced at the 2020 American Astronomical Society winter meeting. ^[12] The observatory is named after Vera C. Rubin. The name honors Rubin and her colleagues' legacy to probe the nature of dark matter by mapping and cataloging billions of galaxies through space and time. ^[25]

The telescope itself is named the Simonyi Survey Telescope, after private donors Charles and Lisa Simonyi. ^[27]

History

The L1 lens for the LSST, 2018

The LSST is the successor to a tradition of sky surveys. ^[28] These started as visually compiled catalogs in the 18th century, such as the Messier catalog. This was replaced by photographic surveys, starting with the 1885 Harvard Plate Collection, the National Geographic Society – Palomar Observatory Sky Survey, and others. By about 2000, the first digital surveys, such as the Sloan Digital Sky Survey (SDSS), began to replace the photographic plates of the earlier surveys.

The LSST evolved from the earlier concept of the Dark Matter Telescope, ^[29] mentioned as early as 1996. ^[30] The fifth decadal report, Astronomy and Astrophysics in the New Millennium, was released in 2001, ^[31] and recommended the "Large-Aperture Synoptic Survey Telescope" as a major initiative. Even at this early stage the basic design and objectives were set:

The Large-aperture Synoptic Survey Telescope (LSST) is a 6.5-m-class optical telescope designed to survey the visible sky every week down to a much fainter level than that reached by existing surveys. It will catalog 90 percent of the near-Earth objects larger than 300 m and assess the threat they pose to life on Earth. It will find some 10,000 primitive objects in the Kuiper Belt, which contains a fossil record of the formation of the solar system. It will also contribute to the study of the structure of the universe by observing thousands of supernovae, both nearby and at large redshift, and by measuring the distribution of dark matter through gravitational lensing. All the data will be available through the National Virtual Observatory... providing access for astronomers and the public to very deep images of the changing night sky.

Early development was funded by a number of small grants, with major contributions in January 2008 by software billionaires Charles and Lisa Simonyi and Bill Gates of $20 million and $10 million, respectively. ^{[32] [27]} $7.5 million was included in the U.S. President's FY2013 NSF budget request. ^[33] The United States Department of Energy is funding construction of the digital camera component by the SLAC National Accelerator Laboratory, as part of its mission to understand dark energy. ^[34]

In the 2010 decadal survey, LSST was ranked as the highest-priority ground-based instrument. ^[35]

NSF funding for the rest of construction was authorized as of 1 August 2014. ^[17] The lead organizations are: ^[34]

• The SLAC National Accelerator Laboratory to design and construct the LSST camera
• The National Optical Astronomy Observatory to provide the telescope and site team
• The National Center for Supercomputing Applications to construct and test the archive and data access center
• The Association of Universities for Research in Astronomy is responsible for overseeing the LSST construction.

In May 2018, the United States Congress surprisingly appropriated much more funding than the telescope had asked for, in hopes of speeding construction and operation. Telescope management was thankful but unsure this would help, since at the late stage of construction they were not cash-limited. ^[19]

As of May 2022 ^[update] , the project critical path was the camera installation, integration and testing. ^[36]

Overview

The Simonyi Survey Telescope design is unique among large telescopes (8-meter-class primary mirrors) in having a very wide field of view: 3.5 degrees in diameter, or 9.6 square degrees. For comparison, both the Sun and the Moon, as seen from Earth, are 0.5 degrees across, or 0.2 square degrees. Combined with its large aperture (and thus light-collecting ability), this will give it a spectacularly large etendue of 319 m²⋅degree². ^[6] This is more than three times the etendue of the largest-view existing telescopes, the Subaru Telescope with its Hyper Suprime Camera ^[37] and Pan-STARRS, and more than an order of magnitude better than most large telescopes. ^[38]

Optics

The LSST primary/tertiary mirror successfully cast, August 2008

Optics of the LSST Telescope

The earliest reflecting telescopes used spherical mirrors which, although easy to fabricate and test, suffer from spherical aberration; a long focal length was needed to reduce spherical aberration to a tolerable level. Making the primary mirror parabolic removes spherical aberration on-axis, but the field of view is then limited by off-axis coma. Such a parabolic primary, with either a prime or Cassegrain focus, was the most common optical design up through the Hale Telescope in 1949. After that, telescopes used mostly the Ritchey–Chrétien design, using two hyperbolic mirrors to remove both spherical aberration and coma, giving a wider useful field of view limited only by astigmatism and higher-order aberrations. Most large telescopes since the Hale use this design—the Hubble and Keck telescopes are Ritchey–Chrétien, for example. LSST will use a three-mirror anastigmat to cancel astigmatism by employing three non-spherical mirrors. The result is sharp images over a wide field of view, but at the expense of some light-gathering power due to the large tertiary mirror obscuring part of the optical path. ^[9]

The telescope's primary mirror (M1) is 8.4 meters (28 ft) in diameter, the secondary mirror (M2) is 3.4 meters (11.2 ft) in diameter, and the tertiary mirror (M3), inside the ring-like primary, is 5.0 meters (16 ft) in diameter. The secondary mirror is expected to be the largest convex mirror in any operating telescope, until surpassed by the Extremely Large Telescope's 4.2-meter secondary in about 2028. The second and third mirrors reduce the primary mirror's light-collecting area to 35 square meters (376.7 sq ft), equivalent to a 6.68-meter-diameter (21.9 ft) telescope. ^[6] Multiplying this by the field of view produces an étendue of 336 m²⋅degree²; the actual figure is reduced by vignetting. ^[39]

The primary and tertiary mirrors (M1 and M3) are designed as a single piece of glass, the "M1M3 monolith". Placing the two mirrors in the same location minimizes the overall length of the telescope, making it easier to reorient quickly. Making them out of the same piece of glass results in a stiffer structure than two separate mirrors, contributing to rapid settling after motion. ^[9]

The optics includes three corrector lenses to reduce aberrations. These lenses, and the telescope's filters, are built into the camera assembly. The first lens, at 1.55 m in diameter, is the largest lens ever built, ^[40] and the third lens forms the vacuum window in front of the focal plane. ^[39]

Unlike many telescopes, ^[41] the Rubin Observatory makes no attempt to compensate for dispersion in the atmosphere. Such correction, which requires re-adjusting an additional element in the optical train, would be very difficult in the 5 seconds allowed between pointings, plus is a technical challenge due to the extremely short focal length. As a result, shorter wavelength bands away from the zenith will have somewhat reduced image quality. ^[42]

Wavefront sensing

The Simonyi telescope uses an active optics system, with wavefront sensors at the corners of the camera, to keep the mirrors accurately figured and in focus. The field of view is too large to use adaptive optics to correct for atmospheric seeing. The process occurs in three stages: ^[43]

1. Laser tracker measurements are used to make sure the components are centered and are close to the intended positions.
2. Open-loop corrections are applied to correct for intrinsic mirror aberrations, component sag as a function of elevation and temperature, and filter selection.
3. Focus and figure measurements are made during normal operation by sensors at the corners of the field of view, and are used to correct the optics.

Diagram of the Active Optics sensors for the Vera Rubin telescope

The precise shape and focus of the mirror assembly is estimated, and then corrected, by comparing the images on four sets of deliberately defocused CCDs (one in front of the focal plane and one behind, see figure at right). Two methods for finding these corrections have been developed. One proceeds analytically, estimating a Zernike polynomial description of the current shape of the mirror, and from this computing a set of corrections to restore figure and focus. The other method uses machine learning to directly compute the corrections from the out of focus images. Both methods appear capable of meeting the design goals.

Camera

The LSST camera sensor

Life-size model of the LSST focal plane array. The array's diameter is 64 cm, and will provide 3.2 gigapixels per image. The image of the Moon (30 arcminutes) is present to show the scale of the field of view. The model is held by Suzanne Jacoby, the Rubin Observatory communications director.

A 3.2-gigapixel prime focus ^{[note 1]} digital camera will take a 15-second exposure every 20 seconds. ^[6] Repointing such a large telescope (including settling time) within 5 seconds requires an exceptionally short and stiff structure. This in turn implies a small f-number, which requires precise focusing of the camera. ^[44]

The 15-second exposures are a compromise to allow spotting both faint and moving sources. Longer exposures would reduce the overhead of camera readout and telescope re-positioning, allowing deeper imaging, but then fast moving objects such as near-Earth objects would move significantly during an exposure. ^[45] Each spot on the sky is imaged with two consecutive 15 second exposures, to efficiently reject cosmic ray hits on the CCDs. ^[46]

The camera focal plane is flat and 64 cm in diameter. The main imaging is performed by a mosaic of 189 CCD detectors, each with 16 megapixels. ^[47] They are grouped into a 5×5 grid of "rafts", where the central 21 rafts contain 3×3 imaging sensors, while the four corner rafts contain only three CCDs each, for guiding and focus control. The CCDs provide better than 0.2-arcsecond sampling, and will be cooled to approximately −100 °C (173 K) to help reduce noise. ^[48]

The camera includes a filter located between the second and third lenses, and an automatic filter-changing mechanism. Although the camera has six filters (ugrizy) covering 330–1080 nm wavelengths, ^[49] the camera's position between the secondary and tertiary mirrors limits the size of its filter changer. It can hold five filters at a time, so each day one of the six must be chosen to be omitted for the following night. ^[50]

Image data processing

Scan of Flammarion engraving taken with LSST in September 2020

Allowing for maintenance, bad weather and other contingencies, the camera is expected to take over 200,000 pictures (1.28  petabytes uncompressed) per year, far more than can be reviewed by humans. Managing and effectively analyzing the enormous output of the telescope is expected to be the most technically difficult part of the project. ^{[52] [53]} In 2010, the initial computer requirements were estimated at 100 teraflops of computing power and 15 petabytes of storage, rising as the project collects data. ^[54] By 2018, estimates had risen to 250 teraflops and 100 petabytes of storage. ^[55]

Once images are taken, they are processed according to three different timescales, prompt (within 60 seconds), daily, and annually. ^[56]

The prompt products are alerts, issued within 60 seconds of observation, about objects that have changed brightness or position relative to archived images of that sky position. Transferring, processing, and differencing such large images within 60 seconds (previous methods took hours, on smaller images) is a significant software engineering problem by itself. ^[57] Approximately 10 million alerts will be generated per night. ^[58] Each alert will include the following: ^{[59] : 22}

• Alert and database ID: IDs uniquely identifying this alert
• The photometric, astrometric, and shape characterization of the detected source
• 30×30 pixel (on average) cut-outs of the template and difference images (in FITS format)
• The time series (up to a year) of all previous detections of this source
• Various summary statistics ("features") computed of the time series

There is no proprietary period associated with alerts—they are available to the public immediately, since the goal is to quickly transmit nearly everything LSST knows about any given event, enabling downstream classification and decision making. LSST will generate an unprecedented rate of alerts, hundreds per second when the telescope is operating. ^{[note 2]} Most observers will be interested in only a tiny fraction of these events, so the alerts will be fed to "event brokers" which forward subsets to interested parties. LSST will provide a simple broker, ^{[59] : 48} and provide the full alert stream to external event brokers. ^[60] The Zwicky Transient Facility will serve as a prototype of LSST system, generating 1 million alerts per night. ^[61]

Daily products, released within 24 hours of observation, comprise the images from that night, and the source catalogs derived from difference images. This includes orbital parameters for Solar System objects. Images will be available in two forms: Raw Snaps, or data straight from the camera, and Single Visit Images, which have been processed and include instrumental signature removal (ISR), background estimation, source detection, deblending and measurements, point spread function estimation, and astrometric and photometric calibration. ^[62]

Annual release data products will be made available once a year, by re-processing the entire science data set to date. These include:

• Calibrated images
• Measurements of positions, fluxes, and shapes
• Variability information
• A compact description of light curves
• A uniform reprocessing of the difference-imaging-based prompt data products
• A catalog of roughly 6 million Solar System objects, with their orbits
• A catalog of approximately 37 billion sky objects (20 billion galaxies and 17 billion stars), each with more than 200 attributes. ^[55]

The annual release will be computed partially by the National Center for Supercomputing Applications, and partially by IN2P3 in France. ^[63]

LSST is reserving 10% of its computing power and disk space for user-generated data products. These will be produced by running custom algorithms over the LSST data set for specialized purposes, using application programming interfaces (APIs) to access the data and store the results. This avoids the need to download, then upload, huge quantities of data by allowing users to use the LSST storage and computation capacity directly. It also allows academic groups to have different release policies than LSST as a whole.

An early version of the LSST image data processing software is being used by the Subaru Telescope's Hyper Suprime-Cam instrument, ^[64] a wide-field survey instrument with a sensitivity similar to LSST but one fifth the field of view: 1.8 square degrees versus the 9.6 square degrees of LSST. New software called HelioLinc3D was developed specifically for the Rubin Observatory, to detect moving objects. ^[65]

Scientific goals

Comparison of primary mirrors of several optical telescopes – the LSST, with its very large central hole, is near the center of the diagram.

LSST will cover about 18,000 deg² of the southern sky with six filters in its main survey, with about 825 visits to each spot. The 5σ (SNR greater than 5) magnitude limits are expected to be r < 24.5 in single images, and r < 27.8 in the full stacked data. ^[66]

The main survey will use about 90% of the observing time. The remaining 10% will be used to obtain improved coverage for specific goals and regions. This includes very deep (r ~ 26) observations, very short revisit times (roughly one minute), observations of "special" regions such as the ecliptic, galactic plane, and the Large and Small Magellanic Clouds, and areas covered in detail by multi-wavelength surveys such as COSMOS and the Chandra Deep Field South. ^[46] Combined, these special programs will increase the total area to about 25,000 deg². ^[6]

Particular scientific goals of the LSST include: ^[67]

• Studying dark energy and dark matter by measuring weak gravitational lensing, baryon acoustic oscillations, and photometry of type Ia supernovae, all as a function of redshift. ^[46]
• Mapping small objects in the Solar System, particularly near-Earth asteroids and Kuiper belt objects. LSST is expected to increase the number of cataloged objects by a factor of 10–100. ^[68] It will also help with the search for the hypothesized Planet Nine. ^{[69] [70]}
• Detecting transient astronomical events including novae, supernovae, gamma-ray bursts, quasar variability, and gravitational lensing, and providing prompt event notifications to facilitate follow-up.
• Mapping the Milky Way.

Because of its wide field of view and sensitivity, LSST is expected to be among the best prospects for detecting optical counterparts to gravitational wave events detected by LIGO and other observatories. ^[71]

It is also hoped that the vast volume of data produced will lead to additional serendipitous discoveries.

NASA has been tasked by the U.S. Congress with detecting and cataloging 90% of the near Earth orbit population of size 140 meters or greater. ^[72] LSST, by itself, is estimated to be capable of detecting 62% of such objects, ^[73] and according to the United States National Academy of Sciences, extending its survey from ten years to twelve would be the most cost-effective way of finishing the task. ^[74]

Rubin Observatory has a program of Education and Public Outreach (EPO). Rubin Observatory EPO will serve four main categories of users: the general public, formal educators, citizen science principal investigators, and content developers at informal science education facilities. ^{[75] [76]} Rubin Observatory will partner with Zooniverse for a number of their citizen science projects. ^[77]

Comparison with other sky surveys

Top-end assembly lowered by 500-ton crane

There have been many other optical sky surveys, some still on-going. For comparison, here are some of the main currently used optical surveys, with differences noted:

• Photographic sky surveys, such as the National Geographic Society – Palomar Observatory Sky Survey and its digitized version, the Digitized Sky Survey. This technology is obsolete, with much less depth, and in general taken from locations with less-than-excellent views. These archives are still used since they span a rather large time interval—more than 100 years in some cases—and cover the entire sky. The plate scans reached a limit of R~18 and B~19.5 over 90% of the sky, and about one magnitude fainter over 50% of the sky. ^[78]
• The Sloan Digital Sky Survey (SDSS) (2000–2009) surveyed 14,555 square degrees of the northern-hemisphere sky with a 2.5-meter telescope. It continues to the present day as a spectrographic survey. Its limiting photometric magnitude ranged from 20.5 to 22.2, depending on the filter. ^[79]
• Pan-STARRS (2010–present) is an ongoing sky survey using two wide-field 1.8-meter Ritchey–Chrétien telescopes located at Haleakala in Hawaii. Until LSST begins operation, it will remain the best detector of near-Earth objects. Its coverage, 30,000 square degrees, is comparable to what LSST will cover. The single-image depth in the PS1 survey was between magnitude 20.9–22.0, depending on filter. ^[80]
• The DESI Legacy Imaging Surveys (2013–present) looks at 14,000 square degrees of the northern and southern sky with the Bok 2.3-meter telescope, the 4-meter Mayall telescope, and the 4-meter Víctor M. Blanco Telescope. The Legacy Surveys make use of the Mayall z-band Legacy Survey, the Beijing–Arizona Sky Survey, and the Dark Energy Survey. The Legacy Surveys avoided the Milky Way since it was primarily concerned with distant galaxies. ^[81] The area of DES (5,000 square degrees) is entirely contained within the anticipated survey area of LSST in the southern sky. ^[82] Its exposures typically reach magnitude 23–24.
• Gaia is an ongoing space-based survey of the entire sky since 2014, whose primary goal is extremely precise astrometry of roughly two billion stars, quasars, galaxies, and solar-system objects. Its collecting area of 0.7 m² does not allow observation of objects as faint as can be included in other surveys, but the location of each object observed is known with far greater precision. While not taking exposures in the traditional sense, it detects objects up to a magnitude of 21.
• The Zwicky Transient Facility (2018–present) is a similar, rapid, wide-field survey to detect transient events. The telescope has an even larger field of view (47 square degrees; 5× the field), but a significantly smaller aperture (1.22 m; 1/30 the area). It is being used to develop and test the LSST automated alert software. Its exposures typically reach magnitude 20–21.
• The Space Surveillance Telescope (2011–present) is a similar rapid wide-field survey telescope used primarily for military applications, with secondary civil applications including space debris and NEO detection and cataloging.

Construction progress

Construction progress of the LSST observatory building at Cerro Pachón as of September 2019

Construction progress of the LSST observatory building at Cerro Pachón as of 2022

The Cerro Pachón site was selected in 2006. The main factors were the number of clear nights per year, seasonal weather patterns, and the quality of images as seen through the local atmosphere (seeing). The site also needed to have an existing observatory infrastructure, to minimize costs of construction, and access to fiber optic links, to accommodate the 30 terabytes of data that LSST will produce each night. ^[83]

As of February 2018, construction was well underway. The shell of the summit building was complete, and 2018 saw the installation of major equipment, including HVAC, the dome, mirror coating chamber, and the telescope mount assembly. It also saw the expansion of the AURA base facility in La Serena and the summit dormitory shared with other telescopes on the mountain. ^[58]

By February 2018, the camera and telescope shared the critical path. The main risk was deemed to be whether sufficient time was allotted for system integration. ^[84]

As of 2017 ^[update] , the project remained within budget, although the budget contingency was tight. ^[58]

In March 2020, work on the summit facility, and the main camera at SLAC, was suspended due to the COVID-19 pandemic, though work on software continued. ^[85] During this time, the commissioning camera arrived at the base facility and was tested there. It was moved to the summit and installed on the mount in August 2022. ^[86]

Mirrors

Artist's conception of the LSST inside its dome.

The primary mirror, the most critical and time-consuming part of a large telescope's construction, was made over a 7-year period by the University of Arizona's Steward Observatory Mirror Lab. ^[87] Construction of the mold began in November 2007, ^[88] mirror casting was begun in March 2008, ^[89] and the mirror blank was declared "perfect" at the beginning of September 2008. ^[90] In January 2011, both M1 and M3 figures had completed generation and fine grinding, and polishing had begun on M3.

The mirror was formally accepted on 13 February 2015, ^{[91] [92]} then placed in the mirror transport box and stored in an airplane hangar. ^[93] In October 2018, it was moved back to the mirror lab and integrated with the mirror support cell. ^[94] It went through additional testing in January/February 2019, then was returned to its shipping crate. In March 2019, it was sent by truck to Houston, Texas, ^[95] was placed on a ship for delivery to Chile, ^[96] and arrived on the summit in May. ^[97] There it will be re-united with the mirror support cell and coated.

The coating chamber, which was used to coat the mirrors once they arrived, itself arrived at the summit in November 2018. ^[94]

The secondary mirror was manufactured by Corning of ultra low expansion glass and coarse-ground to within 40 μm of the desired shape. ^[4] In November 2009, the blank was shipped to Harvard University for storage ^[98] until funding to complete it was available. On 21 October 2014, the secondary mirror blank was delivered from Harvard to Exelis (now a subsidiary of Harris Corporation) for fine grinding. ^[99] The completed mirror was delivered to Chile on 7 December 2018, ^[94] and was coated in July 2019. ^[100]

Building

Cutaway rendering of the telescope, dome, and support building

Site excavation began in earnest on 8 March 2011, ^[101] and the site had been leveled by the end of 2011. ^[102] Also during that time, the design progressed, with significant improvements to the mirror support system, stray-light baffles, wind screen, and calibration screen.

In 2015, a large amount of broken rock and clay was found under the site of the support building adjacent to the telescope. This caused a 6-week construction delay while it was dug out and the space filled with concrete. This did not affect the telescope proper or its dome, whose much more important foundations were examined more thoroughly during site planning. ^{[103] [104]}

The building was declared substantially complete in March 2018. ^[105] The dome was expected to be complete in August 2018, ^[58] but a picture from May 2019 showed it still incomplete. ^[97] The (still incomplete) Rubin Observatory dome first rotated under its own power in November 2019. ^[106]

Telescope mount assembly

Telescope Mount Assembly of the 8.4-meter Simonyi Survey Telescope at Vera C. Rubin Observatory, under construction atop Cerro Pachón in Chile

The telescope mount, and the pier on which it sits, are substantial engineering projects in their own right. The main technical problem is that the telescope must slew 3.5 degrees to the adjacent field and settle within four seconds. ^{[note 3] [107] : 10} This requires a very stiff pier and telescope mount, with very high speed slew and acceleration (10°/sec and 10°/sec², respectively ^[108] ). The basic design is conventional: an altitude over azimuth mount made of steel, with hydrostatic bearings on both axes, mounted on a pier which is isolated from the dome foundations. The LSST pier is unusually large (16 m diameter), robust (1.25-meter-thick walls) and mounted directly to virgin bedrock, ^[107] where care was taken during site excavation to avoid using explosives that would crack it. ^{[104] : 11–12} Other unusual design features are linear motors on the main axes and a recessed floor on the mount. This allows the telescope to extend slightly below the azimuth bearings, giving it a very low center of gravity.

The contract for the Telescope Mount Assembly was signed in August 2014. ^[109] It passed its acceptance tests in 2018 ^[94] and arrived at the construction site in September 2019. ^[110] By April 2023, the mount was declared "essentially complete" and turned over to the Rubin Observatory. ^[111]

Camera construction

In August 2015, the LSST Camera project, which is separately funded by the U.S. Department of Energy (DoE), passed its "critical decision 3" design review, with the review committee recommending DoE formally approve start of construction. ^[112] On August 31, the approval was given, and construction began at SLAC in California. ^[113] As of September 2017, construction of the camera was 72% complete, with sufficient funding in place (including contingencies) to finish the project. ^[58] By September 2018, the cryostat was complete, the lenses ground, and 12 of the 21 needed rafts of CCD sensors had been delivered. ^[114] As of September 2020, the entire focal plane was complete and undergoing testing. ^[115] By October 2021, the last of the six filters needed by the camera had been finished and delivered. ^[116] By November 2021, the entire camera had been cooled to its required operating temperature, so final testing could begin. ^[117]

• 
  Rendering of the LSST camera
• 
  Color-coded cutaway drawing of the LSST camera
• 
  Exploded view of the optical components of the LSST camera
• 
  Vera C. Rubin Observatory Commissioning Camera install

Before the final camera is installed, a smaller and simpler version (the Commissioning Camera, or ComCam) will be used "to perform early telescope alignment and commissioning tasks, complete engineering first light, and possibly produce early usable science data". ^[118]

The camera was reported as completed in early 2024. ^[119] The camera arrived at the observatory in May 2024. ^[120]

Data transport and redaction

The data must be transported from the camera, to facilities at the summit, to the base facilities, and then to the Rubin Observatory United States Data Facility (USDF) at SLAC. ^{[121] [122]} Data is first sent via a $5 million dedicated encrypted network to a secret United States intelligence community facility in California. An automated system detects new events, removes events containing American spy satellites, and releases imagery covering the remaining events to the scientific community one minute later. Complete unredacted images are released 80 hours later, after the satellites' orbits change, avoiding the permanent redaction done to images from the Pan-STARRS survey. ^{[123] [124]}

This transfer must be very fast (100 Gbit/s or better) and reliable, since USDF is where the data will be processed into scientific data products, including real-time alerts of transient events. This transfer uses multiple fiber optic cables from the base facility in La Serena to Santiago, Chile, then via two redundant routes to Miami, Florida, where it connects to existing high speed infrastructure. These two redundant links were activated in March 2018 by the AmLight consortium. ^[125]

Since the data transfer crosses international borders, many different groups are involved. These include the Association of Universities for Research in Astronomy (AURA, Chile, and the USA), REUNA ^[126] (Chile), Florida International University (USA), AmLightExP ^[125] (USA), RNP ^[127] (Brazil), and SLAC USDF (USA), all of which participate in the LSST Network Engineering Team (NET). This collaboration designs and delivers end-to-end network performance across multiple network domains and providers.

Possible impact of satellite constellations

A study in 2020 by the European Southern Observatory estimated that up to 30% to 50% of the exposures around twilight with the Rubin Observatory would be severely affected by satellite constellations. Survey telescopes have a large field of view and they study short-lived phenomena like supernovae or asteroids, ^[128] and mitigation methods that work on other telescopes may be less effective. The images would be affected especially during twilight (50%) and at the beginning and end of the night (30%). For bright trails, the complete exposure could be ruined by a combination of saturation, crosstalk (far away pixels gaining signal due to the nature of CCD electronics), and ghosting (internal reflections within the telescope and camera) caused by the satellite trail, affecting an area of the sky significantly larger than the satellite path itself during imaging. For fainter trails, only a quarter of the image would be lost. ^[129] A previous study by the Rubin Observatory found an impact of 40% at twilight and only nights in the middle of the winter would be unaffected. ^[130]

Possible approaches to this problem would be a reduction of the number or brightness of satellites, upgrades to the telescope's CCD camera system, or both. Observations of Starlink satellites showed a decrease of the satellite trail brightness for darkened satellites. This decrease is not enough to mitigate the effect on wide-field surveys like the one conducted by the Rubin Observatory. ^[131] Therefore SpaceX is introducing a sunshade on newer satellites, to keep the portions of the satellite visible from the ground out of direct sunlight. The objective is to keep the satellites above 7th magnitude, to avoid saturating the detectors. ^[132] This limits the problem to only the trail of the satellite and not the whole image. ^[133] As of 2023, Starlink generation 2 "mini" satellites have achieved mean apparent magnitudes greater than 7. ^[134]

Gallery

• 
  Clear skies at Cerro Pachón ^[135]
• 
  Vera C. Rubin Observatory under construction ^[136]
• 
  Telescope mount assembly, taken from the dome during bridge crane installation ^[137]
• 
  Focal plane of the LSST Cam. It is 60 cm (2 feet) wide, has 189 sensors to produce 3200-megapixel images. ^[138]
• 
  Optical engineers Justin Wolfe (left) and Simon Cohen with the r filter for the LSST Cam ^[139]
• 
  The LSST Cam chilled to subzero temperatures using both cooling systems ^[140]
• 
  Comet Leonard, the Rubin Observatory, the planet Venus, and various stars
• 
  Night Light over Vera C. Rubin Observatory with the brightening of the sky due to the artificial light that can be seen as clusters of bright lights on the horizon

Notes

1. The camera is actually at the tertiary focus, not the prime focus, but being located at a "trapped focus" in front of the primary mirror, the associated technical problems are similar to those of a conventional prime-focus survey camera.
2. 10 million events per 10 hour night is 278 events per second.
3. Five seconds are allowed between exposures, but one second is reserved for the mirrors and instrument to be aligned, leaving four seconds for the structure.

See also

• Astronomy portal

• List of largest optical reflecting telescopes
• Pan-STARRS
• Dark Energy Survey
• VISTA (Visible and Infrared Survey Telescope for Astronomy)
• VLT Survey Telescope

References

1. Eric E. Mamajek (2012-10-10). "Accurate Geodetic Coordinates for Observatories on Cerro Tololo and Cerro Pachon". p. 13. arXiv: 1210.1616 [astro-ph.IM]. Measured GPS position for future site of LSST pier is WGS-84 30°14′40.68″S70°44′57.90″W / 30.2446333°S 70.7494167°W / -30.2446333; -70.7494167 , with ±0.10″ uncertainty in each coordinate.
2. Mugnier, C.P., C.M.S., Clifford J. (January 2007). "Grids & Datums: Republic of Chile" (PDF). Photogrammetric Engineering & Remote Sensing. 73 (1): 11. Retrieved 2015-08-08.
3. Charles F. Claver; et al. (2007-03-19). "LSST Reference Design" (PDF). LSST Corporation. pp. 64–65. Archived from the original (PDF) on 2015-04-08. Retrieved 2008-12-10. The map on p. 64 shows the Universal Transverse Mercator location of the centre of the telescope pier at approximately 6653188.9 N, 331859.5 E, in zone 19J. Assuming the PSAD56 (La Canoa) datum, widely used in South America, ^[2] this translates to WGS84 30°14′39.6″S70°44′57.8″W / 30.244333°S 70.749389°W / -30.244333; -70.749389 . Other datums do not lead to a peak.
4. Victor Krabbendam; et al. (2011-01-11). "LSST Telescope and Optics Status" (PDF). American Astronomical Society 217th Meeting (poster). Seattle, Washington. Retrieved 2015-08-05. This updated plan shows the revised telescope centre at 6653188.0 N, 331859.1 E (PSAD56 datum). This is the same WGS84 location to the resolution shown.
5. "LSST Summit Facilities". 2009-08-14. Retrieved 2015-08-05.
6. "LSST System & Survey Key Numbers". LSST Corporation. 3 April 2013. Retrieved 2015-08-05.
7. "Monthly updates". LSST Corporation. 6 December 2016. Archived from the original on 2 July 2023. Retrieved 18 October 2023.
8. Willstrop, Roderick V. (October 1, 1984). "The Mersenne-Schmidt: A three-mirror survey telescope". Monthly Notices of the Royal Astronomical Society . 210 (3): 597–609. Bibcode:1984MNRAS.210..597W. doi: 10.1093/mnras/210.3.597 . ISSN   0035-8711 . Retrieved 2015-08-05.
9. Gressler, William (June 2, 2009). "LSST Optical Design Summary" (PDF). LSE-11. Archived from the original (PDF) on 2012-03-20. Retrieved 2011-03-01.
10. Tuell, Michael T.; Martina, Hubert M.; Burge, James H.; Gressler, William J.; Zhao, Chunyu (July 22, 2010). "Optical testing of the LSST combined primary/tertiary mirror" (PDF). Proc. SPIE 7739, Modern Technologies in Space- and Ground-based Telescopes and Instrumentation. Modern Technologies in Space- and Ground-based Telescopes and Instrumentation. 7739 (77392V): 77392V. Bibcode:2010SPIE.7739E..2VT. doi:10.1117/12.857358. S2CID   49567158.
11. Overbye, Dennis (11 January 2020). "Vera Rubin Gets a Telescope of Her Own – The astronomer missed her Nobel Prize. But she now has a whole new observatory to her name". The New York Times . Retrieved 11 January 2020.
12. "NSF-supported observatory renamed for astronomer Vera C. Rubin". www.nsf.gov. Retrieved 2020-01-07.
13. "Press Release LSSTC-04: Site in Northern Chile Selected for Large Synoptic Survey Telescope" (PDF). LSST. 17 May 2006. Retrieved 1 August 2015.
14. "About Rubin Observatory". 2 April 2013. Retrieved 26 January 2022.
15. "LSST General Public FAQs" . Retrieved 11 September 2020.
16. "Camera". LSST. 26 March 2013. Retrieved 1 August 2015.
17. Kahn, Steven; Krabbendam, Victor (August 2014). "LSST Construction Authorization" (Press release). Lsst Corp.
18. Boilerplate text, Rubin Observatory, accessed May 28, 2020
19. Mervis, Jeffrey (21 May 2018). "Surprise! House spending panel gives NSF far more money for telescope than it requested". AAAS.
20. "LSST First Stone" (Press release). LSST Corporation. 14 April 2015.
21. "The Large Synoptic Survey Telescope: Unlocking the secrets of dark matter and dark energy". Phys.org. May 29, 2015. Retrieved 3 June 2015.
22. "Locations of Target Fields Observed during On-sky Commissioning Campaign with ComCam". LSST Corporation. 3 November 2024.
23. "Monthly updates". LSST Corporation. 6 December 2016. Archived from the original on 2 July 2023. Retrieved 16 October 2023.
24. "Search | Legacy Survey of Space and Time". www.lsst.org. Retrieved 2020-02-12.
25. "H.R. 3196, the Vera C. Rubin Observatory Designation Act | House Committee on Science, Space and Technology". science.house.gov. Retrieved 2020-01-07.
26. Johnson, Eddie Bernice (2019-12-20). "H.R.3196 – 116th Congress (2019-2020): Vera C. Rubin Observatory Designation Act". www.congress.gov. Retrieved 2020-01-07.
27. "FAQ | Vera Rubin Observatory". www.vro.org. Retrieved 2020-02-04.
28. Djorgovski, S. George; Mahabal, Ashish; Drake, Andrew; Graham, Matthew; Donalek, Ciro (2013). "Sky Surveys". In Oswalt, Terry (ed.). Planets, Stars and Stellar Systems. Springer Netherlands. pp. 223–281. arXiv: 1203.5111 . doi:10.1007/978-94-007-5618-2_5. ISBN   978-94-007-5617-5. S2CID   119217296.
29. Tyson, A.; Angel, R. Clowes, Roger; Adamson, Andrew; Bromage, Gordon (eds.). The Large-aperture Synoptic Survey Telescope. The New Era of Wide Field Astronomy, ASP Conference Series. Vol. 232. San Francisco, California: Astronomical Society of the Pacific. p. 347. ISBN   1-58381-065-X.
30. Press, W. H. (9–14 July 1995). Kochanek, C. S.; Hewitt, Jacqueline N. (eds.). Prognosticating The Future Of Gravitational Lenses. Astrophysical applications of gravitational lensing: proceedings of the 173rd Symposium of the International Astronomical Union. Vol. 173. International Astronomical Union. Melbourne, Australia: Kluwer Academic Publishers; Dordrecht. p. 407.
31. Astronomy and astrophysics in the new millennium. Washington, D.C.: National Academy Press. 2001. ISBN   978-0-309-07312-7.
32. Overbye, Dennis (January 3, 2008). "Donors Bring Big Telescope a Step Closer". The New York Times . Retrieved 2008-01-03.
33. "LSST Project Office Update". March 2012. Retrieved 2012-04-07.
34. "World's largest digital camera gets green light". 2011-11-08. Retrieved 2012-04-07./
35. "Large Synoptic Survey Telescope gets Top Ranking, "a Treasure Trove of Discovery"" (PDF) (Press release). LSST Corporation. 2010-08-16. Retrieved 2015-08-05.
36. "Monthly Updates". 6 December 2016.
37. Aihara, Hiroaki; et al. (2018). "The Hyper Suprime-Cam SSP Survey: Overview and survey design". Publications of the Astronomical Society of Japan. 70 (SP1): S4. arXiv: 1704.05858 . Bibcode:2018PASJ...70S...4A. doi:10.1093/pasj/psx066. S2CID   119266217.
38. "Community Science Input and Participation". LSST. 18 June 2013.
39. "Rubin Observatory Optical Design". Rubin Observatory. 3 April 2013.
40. Overton, Gail (2019-09-13). "LLNL ships world's largest optical lens to SLAC for the LSST telescope". Laser Focus World.
41. Miyazaki, S.; Komiyama, Y.; Kawanomoto, S.; Doi, Y.; Furusawa, H.; Hamana, T.; Hayashi, Y.; Ikeda, H.; Kamata, Y.; Karoji, H.; and Koike, M. (2018). "Hyper Suprime-Cam: System design and verification of image quality". Publications of the Astronomical Society of Japan. 70 (SP1): S1. doi:10.1093/pasj/psx063.
42. Seppala, Lynn (24 December 2002). "Improved optical design for the Large Synoptic Survey Telescope (LSST)". Proc. SPIE 4836, Survey and Other Telescope Technologies and Discoveries. Astronomical Telescopes and Instrumentation, 2002. doi:10.1117/12.461389. No correction for atmospheric dispersion or ADC has been incorporated. The extremely fast focal ratio and the expected rapid pointing changes during the course of observations preclude any compensation technique. Reduced image quality will have to be accepted at the lower wavelength bands at angles away from the zenith.
43. "Rubin Observatory Simonyi Survey Telescope Active Optics".
44. Kahn, Steven M. (2014). "The Large Synoptic Survey Telescope" (PDF).
45. "LSST Tour". LSST.
46. Ivezić, Ž.; et al. (2014-08-29). "LSST: From Science Drivers to Reference Design and Anticipated Data Products (v1.0)". The Astrophysical Journal. 873 (2): 111. arXiv: 0805.2366 . Bibcode:2019ApJ...873..111I. doi: 10.3847/1538-4357/ab042c . S2CID   16790489., this is a comprehensive overview of the LSST.
47. "Technical Details". Large Synoptic Survey Telescope. 11 June 2013. Retrieved 2016-03-03.
48. "LSST Camera Focal Plane | Rubin Observatory". www.lsst.org. 11 June 2013.
49. "LSST filters vs. SDSS". community.lsst.org. 27 November 2017.
50. "LSST Camera filter changer". gallery.lsst.org.
51. "Sensors of world's largest digital camera snap first 3,200-megapixel images at SLAC". SLAC National Accelerator Laboratory.
52. Stephens, Matt (2008-10-03). "Mapping the universe at 30 Terabytes a night: Jeff Kantor, on building and managing a 150 Petabyte database". The Register . Retrieved 2008-10-03.
53. Stephens, Matt (2010-11-26). "Petabyte-chomping big sky telescope sucks down baby code". The Register . Retrieved 2011-01-16.
54. Boon, Miriam (2010-10-18). "Astronomical Computing". Symmetry Breaking. Retrieved 2010-10-26.
55. "Data Management Technology Innovation". LSST. 19 June 2013.
56. "Data Products". LSST. 11 June 2013.
57. Morganson, Eric (22 May 2017). From DES to LSST: Transient Processing Goes from Hours to Seconds (PDF). Building the Infrastructure for Time-Domain Alert Science in the LSST Era. Tucson, Arizona.
58. Krabbendam, Victor (28 November 2017). LSST status update. LSST Project/NSF/AURA. Figures shown at 33:00.
59. Bellm, Eric (26 Feb 2018). Alert Streams in the LSST Era: Challenges and Opportunities. Real-Time Decision Making: Applications in the Natural Sciences and Physical Systems. Berkeley, California.
60. Telescope, Large Synoptic Survey (2019-11-19). "Alert Brokers". Rubin Observatory. Retrieved 2022-04-22.
61. Bellm, Eric (22 May 2017). Time Domain Alerts from LSST & ZTF (PDF). Building the Infrastructure for Time-Domain Alert Science in the LSST Era. Tucson, Arizona.
62. Jurić, M.; Axelrod, T.; Becker, A. C.; Becla, J.; Bellm, Eric; Bosch, J. F.; et al. (9 Feb 2018). "Data Products Definition Document" (PDF). LSST Corporation. p. 53.
63. "LSST-French Connection". April 2015.
64. Bosch, J.; Armstrong, R.; Bickerton, S.; Furusawa, H.; Ikeda, H.; Koike, M.; Lupton, R.; Mineo, S.; Price, P.; Takata, T.; Tanaka, M. (8 May 2017). "The Hyper Suprime-Cam software pipeline". Publications of the Astronomical Society of Japan. 70. arXiv: 1705.06766 . doi:10.1093/pasj/psx080. S2CID   119350891.
65. Andrews, Robin George (August 5, 2023). "Killer Asteroid-Spotting Software Could Help Save the World". The New York Times .
66. Kahn, Steven M.; Bankert, Justin R.; Chandrasekharan, Srinivasan; Claver, Charles F.; Connolly, A. J.; et al. "Chapter 3: LSST System Performance" (PDF). LSST.
67. "LSST Science Goals". www.lsst.org. The Large Synoptic Survey Telescope. 9 September 2014. Retrieved 3 April 2018.
68. Jones, R. Lynne; Juric, Mario; Ivezic, Zeljko (10 November 2015). Asteroid Discovery and Characterization with the Large Synoptic Survey Telescope (LSST). IAU-318 – Asteroids: New Observations, New Models. arXiv: 1511.03199 .
69. "The search for Pluto's successor continues with Rubin Observatory, could Planet X be the answer?". FirstPost. June 29, 2020. Retrieved 2021-02-17.
70. Siraj, Amir; Loeb, Abraham (July 2020). "Searching for Black Holes in the Outer Solar System with LSST". The Astrophysical Journal Letters. 898 (1): L4. arXiv: 2005.12280 . Bibcode:2020ApJ...898L...4S. doi: 10.3847/2041-8213/aba119 . S2CID   218889510. L4.
71. "LSST Detection of Optical Counterparts of Gravitational Waves 2019". markalab.github.io.
72. "Planetary Defense Frequently Asked Questions". NASA. 29 Aug 2017.
73. Grav, Tommy; Mainzer, A. K.; Spahr, Tim (June 2016). "Modeling the performance of the LSST in surveying the near-Earth object population". The Astronomical Journal. 151 (6): 172. arXiv: 1604.03444 . Bibcode:2016AJ....151..172G. doi: 10.3847/0004-6256/151/6/172 .
74. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. National Academies Press. 2010. doi:10.17226/12842. ISBN   978-0-309-14968-6., page 49.
75. "Education & Public Outreach". LSST. 11 May 2015.
76. "Large Synoptic Survey Telescope (LSST) EPO Design". LSST Corporation. 29 Nov 2017.
77. "PROJECT & SCIENCE NEWS for Tuesday, May 8, 2018". LSST. 8 May 2018.
78. Lasker, Barry M.; Lattanzi, Mario G.; McLean, Brian J.; Bucciarelli, Beatrice; Drimmel, Ronald; Garcia, Jorge; Greene, Gretchen; Guglielmetti, Fabrizia; Hanley, Christopher; Hawkins, George; Laidler, Victoria G.; Loomis, Charles; Meakes, Michael; Mignani, Roberto; Morbidelli, Roberto; Morrison, Jane; Pannunzio, Renato; Rosenberg, Amy; Sarasso, Maria; Smart, Richard L.; Spagna, Alessandro; Sturch, Conrad R.; Volpicelli, Antonio; White, Richard L.; Wolfe, David; Zacchei, Andrea (2008-07-11). "The Second-Generation Guide Star Catalog: Description and Properties". The Astronomical Journal. 136 (2). American Astronomical Society: 735–766. arXiv: 0807.2522 . Bibcode:2008AJ....136..735L. doi:10.1088/0004-6256/136/2/735. ISSN   0004-6256. S2CID   17641056.
79. "SDSS DR12 Scope" . Retrieved 2021-07-07.
80. "The Pan-STARRS data archive home page" . Retrieved 2021-07-07.
81. Survey, Legacy (2012-11-08). "Index". Legacy Survey. Retrieved 2020-02-04.
82. Ivezić, Željko (24 Mar 2014). Similarities and differences between DES and LSST (PDF). Joint DES-LSST workshop. Fermilab.
83. "Site in Northern Chile Selected for Large Synoptic Survey Telescope" (PDF) (Press release). LSST. 17 May 2006.
84. Kahn, Steven M. (21 February 2018). Project Status (PDF). LSST Science Advisory Committee Meeting. Princeton.
85. "COVID-19 Construction Shutdown". LSST. Apr 14, 2020.
86. "Rubin Commissioning Camera Installed on the Telescope Mount". LSST. 30 August 2022.
87. "Steward Observatory Mirror Lab Awarded Contract for Large Synoptic Survey Telescope Mirror". University of Arizona News. October 29, 2004.
88. "Mirror Fabrication | Rubin Observatory". www.lsst.org.
89. "LSST High Fire Event".
90. "Giant Furnace Opens to Reveal 'Perfect' LSST Mirror Blank" (PDF). LSST Corporation. 2009-09-02. Retrieved 2011-01-16.
91. LSST.org (April 2015). "M1M3 Milestone Achieved". LSST E-News. 8 (1). Retrieved 2015-05-04.
92. Sebag, Jacques; Gressler, William; Liang, Ming; Neill, Douglas; Araujo-Hauck, C.; Andrew, John; Angeli, G.; et al. (2016). LSST primary/tertiary monolithic mirror. Ground-based and Airborne Telescopes VI. Vol. 9906. International Society for Optics and Photonics. pp. 99063E.
93. Beal, Tom (28 February 2015). "Big mirror about to move from UA lab". Arizona Daily Star. Retrieved 2015-05-04.
94. "News | Vera C. Rubin Observatory Project". project.lsst.org.
95. "Bon Voyage (Buen Viaje) M1M3!". LSST. 13 March 2019.
96. "M1M3 Sails for Chile". LSST. 11 April 2019.
97. "On this spectacular sunny day, the @LSST M1M3 reached the summit!".
98. "LSST M2 Substrate Complete and Shipped". LSST E-News. 2 (4). January 2010.
99. "LSST M2 Substrate Received by Exelis". LSST E-News. 7 (4). December 2014.
100. "M2 Coating Completed". LSST. Jul 30, 2019.
101. "Kaboom! Life's a Blast on Cerro Pachón". LSST Corporation. April 2011. Retrieved 2015-08-05.
102. Krabbendam, Victor; et al. (2012-01-09). "Developments in Telescope and Site" (PDF). American Astronomical Society 219th Meeting (poster). Austin, Texas. Retrieved 2012-01-16.
103. "Excavation Activities on Cerro Pachón". LSST E-News. 8 (2). August 2015.
104. Barr, Jeffrey D.; Gressler, William; Sebag, Jacques; Seriche, Jaime; Serrano, Eduardo (27 July 2016). "LSST summit facility construction progress report: Reacting to design refinements and field conditions". In Hall, Helen J.; Gilmozzi, Roberto; Marshall, Heather K. (eds.). Ground-based and Airborne Telescopes VI. Vol. 9906. p. 99060P. Bibcode:2016SPIE.9906E..0PB. doi:10.1117/12.2233383. ISBN   978-1-5106-0191-8. S2CID   125565259., p. 12
105. "A Key Event". 23 March 2018.
106. LSST Astronomy, @LSST, 1 November 2019.
107. Neill, Douglas R.; Krabbendam, Victor L. (2010). LSST Telescope mount and pier design overview. Ground-based and Airborne Telescopes III. Vol. 7733. International Society for Optics and Photonics. pp. 77330F. Bibcode:2010SPIE.7733E..0FN. doi:10.1117/12.857414.
108. Krabbendam, Victor L. (June 12, 2018). "The Large Synoptic Survey Telescope (LSST) Construction Status – 2018". LSST.
109. "LSST: TMA Contract Officially Signed". LSST E-News. 7 (4). December 2014.
110. "The TMA Arrives at the Summit". Vera Rubin Observatory. September 24, 2019.
111. "TMA Achieves Substantial Completion". 18 April 2023.
112. "LSST Camera Team Passes DOE CD-3 Review". 10 August 2015. Retrieved 2015-08-11.
113. "World's Most Powerful Digital Camera Sees Construction Green Light" (Press release). SLAC. 31 August 2015.
114. Krabbendam, Victor L. (20 September 2018). "The Large Synoptic Survey Telescope (LSST) Construction Status" (PDF). LSST.
115. Gnida, Manuel (September 8, 2020). "Sensors of world's largest digital camera snap first 3,200-megapixel images at SLAC". Stanford University.
116. "LLNL engineers deliver final optical components for world's newest telescope: the Vera C. Rubin Observatory". 19 October 2021.
117. "Camera Cooldown". Rubin Observatory. 12 Nov 2021.
118. Haupt, J.; Kuczewski, J.; O'Connor, P. "The Large Synoptic Survey Telescope Commissioning Camera" (PDF). Brookhaven National Laboratory.
119. Lea, Robert (2024-04-03). "The world's largest digital camera is ready to investigate the dark universe". Space.com. Retrieved 2024-04-04.
120. "LSST Camera arrives at Rubin Observatory in Chile | symmetry magazine". www.symmetrymagazine.org. 2024-05-22. Retrieved 2024-05-23.
121. "Rubin Observatory US Data Facility" (PDF). April 2021.
122. "Lighting up the LSST Fiber Optic Network: From Summit to Base to Archive". LSST Project Office. 10 April 2018.
123. Andersen, Ross (2024-12-02). "When a Telescope Is a National-Security Risk". The Atlantic. Retrieved 2024-12-02– via MSN.
124. O’Mullane, William; Allbery, Russ; Lim, K. T. (2024-07-09). "Rubin Data and Information Security Plan" (PDF). Vera C. Rubin Observatory Rubin Observatory Operations.
125. "Amlight-Exp Activates two new 100 Gbps Points-of-Presence Enhancing Infrastructure for Research and Education" (Press release). Florida International University. 29 March 2018.
126. "Chile inaugura primer tramo de Red Óptica de alta velocidad" [Chile inaugurates first stretch of High Speed Optical Network] (Press release) (in Spanish). Red Universitaria Nacional. 16 April 2018.
127. "Brazilian scientists to partake in International Astronomy project" (Press release). Rede Nacional de Ensino e Pesquisa.
128. "New ESO Study Evaluates Impact of Satellite Constellations on Astronomical Observations". www.eso.org. Retrieved 2020-03-20.
129. Hainaut, Olivier R.; Williams, Andrew P. (2020-03-05). "On the Impact of Satellite Constellations on Astronomical Observations with ESO telescopes in the Visible and Infrared Domains". Astronomy & Astrophysics. A121: 636. arXiv: 2003.01992 . Bibcode:2020A&A...636A.121H. doi:10.1051/0004-6361/202037501. ISSN   0004-6361. S2CID   211987992.
130. Rubin Observatory Project Science Team (PST) (March 3, 2020). "Impact on Optical Astronomy of LEO Satellite Constellations" (PDF). docushare.lsst.org.
131. Tregloan-Reed, J.; Otarola, A.; Ortiz, E.; Molina, V.; Anais, J.; González, R.; Colque, J. P.; Unda-Sanzana, E. (2020-03-16). "First observations and magnitude measurement of SpaceX's Darksat". Astronomy & Astrophysics. L1: 637. arXiv: 2003.07251 . doi:10.1051/0004-6361/202037958. S2CID   212725531.
132. Clark, Stephen (May 5, 2020). "SpaceX to debut satellite-dimming sunshade on next Starlink launch". Astronomy Now.
133. "Vera C. Rubin Observatory – Impact of Satellite Constellations". Rubin Observatory. May 19, 2020.
134. Mallama, Anthony; Cole, Richard E.; Harrington, Scott; Hornig, Andreas; Respler, Jay; Worley, Aaron; Lee, Ron (2023-06-11), Starlink Generation 2 Mini Satellites: Photometric Characterization, arXiv: 2306.06657
135. "Clear Skies at Cerro Pachón" . Retrieved 17 June 2021.
136. "New Initiative to Help Unravel Cosmic Mysteries with Big Data" . Retrieved 20 September 2021.
137. "The Rubin Observatory Telescope Mount Awakens" . Retrieved 26 October 2021.
138. "Rubin Observatory Receives Two Guinness World Records for Its Camera and Lenses" . Retrieved 26 October 2021.
139. "Final Filters Delivered for Rubin Observatory Camera" . Retrieved 26 October 2021.
140. "Rubin Camera Chills Out" . Retrieved 2 December 2021.

External links

• Official website
• Legacy Survey of Space and Time official website
• LSST construction site webcams
• LSST reports and documentation
• New Scientist SPACE Article
• LSST Tutorials for Experimental Particle Physicists is a detailed explanation of LSST's design (as of February 2006) and weak lensing science goals that does not assume much astronomy background.
• The New Digital Sky is a video of a July 25, 2006 presentation at Google about the LSST, particularly the data management issues.
• HULIQ Google participation announcement
• LSST Science Collaborations; Abell, Paul A.; Allison, Julius; Anderson, Scott F.; Andrew, John R.; Angel, J. Roger P.; Armus, Lee; Arnett, David; Asztalos, S. J. (2009-10-16). LSST Science Book, Version 2.0. Vol. 0912. p. 201. arXiv: 0912.0201 . Bibcode:2009arXiv0912.0201L . Retrieved 2011-01-16., an updated and expanded overview.