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Comment: Published by Scroll Versions from space DraftMASTDATA and version 1.1

Focal point for the initial release of JWST data.


Data from the James Webb Space Telescope were released to the community beginning on 2022 July 12. These pages describe the release timeline, some of the featured products, and the means by which users may obtain data products.

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Table of Contents

Table of Contents

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rootPageJWST Data Release

Release Timeline
Release Timeline
Release Timeline

Data were released in stages, as depicted in the graphic below. Data are hosted on multiple platforms in an effort to serve large amounts of data to a wide audience in a timely way.


JWST data release timeline, beginning with the press conference on 12 July and culminating on 17 July with all data being available in MAST. First Images and Commissioning data will be available sooner in AWS.Image Modified

JWST data were released in stages (green circles) by program type. It takes some time for all of the data to be migrated from storage where exclusive access is enforced to storage where there are no restrictions. During the migration (orange bars) logged-in users were able to retrieve the data, but anonymous users could only retrieve data that had been migrated. Data that were staged on the AWS platform became available to everyone immediately upon release, or as soon thereafter as possible once data have been processed. Note: times are in US EDT (UTC-4). 

Data from CAL, DD, ENG, ERS, and GO/GTO are bundled under "Cycle-1" programs in the timeline above. Exclusive access periods for GO/GTO data will continue to be enforced where applicable.

Program Categories

Data from the following categories of programs will be made available in MAST (and in two cases, Amazon Web Services):

AbbrProgram TypeAccessNotes
CALCalibrationPublicCycle 1 program to collect data for calibrating science instruments. Some include observations of external targets.

Observations obtained in the first 6 months of flight to characterize and adjust telescope and instrument functionality and performance.

Available from AWS.

DDDirector's DiscretionPublicOff-cycle grants of urgent observations.
ENGEngineeringPublicNon-standard observations meant to characterize instrument health and functionality.
EROEarly Release ObservationsPublic

Webb First Science data that illustrate the capabilities of JWST and the science instruments.

Available from AWS.

ERSEarly Release SciencePublicCycle 1 programs that will execute early.
GO/GTOGuest/Guaranteed-Time ObserverEAP+PublicCycle 1 programs, a few of which have immediate public access.
titleUse AWS for Data Retrievals

We strongly recommend that you retrieve data from the AWS S3 bucket if available. This will off-load network traffic from STScI, and will offer higher availability and throughput for data transfers. Datasets on AWS are the ERO science data and the Commissioning (COM) data. The volume of all COM data is approximately 46 approaches 150 TB.

User Support

For MAST user support, contact the HelpDesk: See the Archive Support page for details and other resources.

Please acknowledge the use of data obtained from MAST in publications.

For Further Reading...