Building of LSST ObservatoryA photograph and rendering mix of the exterior of the LSST building on Cerro Pachón in Chile. Image credit: LSST/NSF/AURA

The Large Synoptic Survey Telescope (LSST), currently under construction on Cerro Pachón in Chile, is an 8-meter-class telescope coupled to a 3.2-gigapixel camera – the world’s largest digital camera ever fabricated for optical astronomy.

LSST Operations will be coordinated and managed by NSF’s OIR Lab.

The Large Synoptic Survey Telescope (LSST), currently under construction in Chile, will conduct an unprecedented, decade-long survey of the optical sky. Once LSST begins operations in October 2022, it will revolutionize the field of astronomy and what we know about the Universe.

LSST is not just a telescope, it’s a complex, integrated system consisting of an 8-meter class wide-field ground-based telescope, a 3.2-gigapixel camera, and an automated data processing system. LSST seeks to enable science in four main areas: 

  • The nature of dark matter, and understanding dark energy 
  • Cataloging the Solar System 
  • Exploring the changing sky
  • Milky Way structure and formation


The Telescope

The 8.4-meter LSST features a unique three-mirror design, which creates an exceptionally wide field of view. The telescope will operate on an automated cadence, surveying the entire visible sky every few nights. The telescope is located on the Cerro Pachón ridge in north-central Chile, approximately 100 km (60 miles) by road from the support town of La Serena, where the LSST Base Facility is located.

The Camera

The LSST Camera is the largest digital camera ever constructed for astronomy — it’s roughly the size of a small car and weighs almost 2800 kg (6200 lbs). The focal plane consists of 189 charge-coupled device (CCD) sensors arranged on 21 “rafts” for a combined 3.2 gigapixels. The camera includes an automated filter-changing system with six filters: u,g,r,i,z, and y. 

The Data

Dedicated computer facilities will process LSST data in real time, issuing worldwide, public alerts within 60 seconds of detected changes in the sky. LSST will generate approximately 20 terabytes of data per night, and over its ten-year survey will produce a 15 petabyte catalog database. 

Public Engagement

A subset of data will be widely available through LSST’s Education and Public Outreach (EPO) dynamic website portal, offering tools and activities for formal educators, citizen scientists, informal science centers, and the general public to engage, explore, and discover.

LSST was the top-ranked large ground-based project in the 2010 Astrophysics Decadal Survey. Engineering first light is anticipated in mid 2021, followed by science first light later in 2021 and full operations for a ten-year survey commencing in October 2022. AURA operates LSST for the National Science Foundation under a cooperative agreement.

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. 

logos of LSST funding and managing agencies