Except for a few special cases, ESO data are world-wide available and can be requested after the proprietary period by the astronomical community.
Please read the official ESO data access policy.

Contents of the ESO Archive

• All raw observations performed at the La Silla Paranal Observatory on the NTT, MPG-ESO 2.2m, ESO 3.6m, VLT/VLTI and APEX telescopes.
  
• The raw data from the UKIRT Infrared Deep Sky Survey (UKIDSS) taken with the Wide Field Infrared Camera (WFCAM). Per agreement between ESO and the United Kingdom, these data are made available to the astronomers from the ESO member states. Please note that WFCAM data stored in the ESO archive are tile-compressed.
• Various data products:
  • Data from the commissioning and science verification/demonstration phases, see the ESO science activities page or the archive list of data packages.
  • Data from the ESO Imaging Survey and other projects, see the list of data packages.
  • Advanced Data Products, see the data release overview page and the data product submission guidelines.
  • Phase3 Data Products (including reduced images from the VISTA public surveys), see the Phase3 data release overview page

Science data are stored in the archive together with the calibration and auxiliary data.
Find out more about the ESO optical and infrared instrumentation and the APEX submillimeter instrumentation.

ESO Archive Browsers

To search and retrieve ESO data, use one of the following archive browsers:

• Raw data query form, a unified and observatory-oriented access to the ESO collection of raw data for astronomers with no previous experience with ESO instruments.
• Instrument specific query forms (for raw data only), several instrument specific and technically-oriented access points to the ESO archive for astronomers already well familiar with ESO instrument setups and observing strategies.
• Reduced data query form, a unified and science-oriented access to the ESO collection of historical advanced data products.
• Query interfaces for ESO data products collected through the Phase3 process since April 2011:
  • Generic Phase3 Data Products
  • Imaging Phase3 Data Products
  • VISTA-specific Phase3 Data Products

To monitor the progress of your data requests, use the archive request status tool.
A section on Frequently Asked Questions provides additional guidance on the use of the ESO/ST-ECF Science Archive Facility.

Catalogue Facility

The Catalogue Facility offers query access to those scientific data catalogues that were produced by the principal investigators of ESO observing programmes, and that were integrated into the ESO science archive via the Phase3 process.

• Catalogues query interface (registration required)
• Catalogues query interface help page

Additional Query Forms

• Observation schedule query form
• Ambient conditions database, includes nightly measurements of environmental parameters at La Silla and Paranal observatory sites.
• ESO data-based refereed publications are recorded in the so-called ESO Telescope Bibliography database. It is compiled by scanning the major astronomical journals for scientific papers based on data obtained with ESO telescopes. The ESO Telescope Bibliography can also be queried through a filter at the NASA ADS from which active links are provided to the ESO Archive. Just follow the D-links ("On-line Data"). Unlike the ESO interface, however, ADS does not cater for queries limited to specific telescopes or instruments, and therefore the entire database is searched. Lists derived from the ESO Telescope Bibliography are printed as an Annex to the ESO Annual Report.

• Data direct retrieval form (for raw data only)

Registration and Acknowledgments

To request data one has to register to the ESO User Portal.
Please do not forget to acknowledge the use of archive data in your publications.