Rubin Data Preview 1 (2026): The First Rubin Observatory Data

Rubin Observatory’s Data Preview 1, released to scientists on 30 June 2025 and described in a 2026 paper, is the first data from the NSF-DOE Vera C. Rubin Observatory. Built from 1,792 exposures taken in late 2024, it covers about 15 square degrees and holds some 2.3 million astronomical objects.

What was Data Preview 1 for?

Rubin was built to run the Legacy Survey of Space and Time, a 10-year survey of the southern sky laid out in the LSST design paper. A survey that size depends on software as much as on telescopes: every image must be calibrated, stacked, compared and cataloged automatically. Before the main survey began, the community needed a first real data set to test those pipelines and start early science. Data Preview 1, or DP1, is that first look, small but built with the same kinds of products the full survey will deliver at far larger scale.

What the paper describes

• The data. 1,792 exposures taken over 48 nights in late 2024 with the Commissioning Camera, LSSTComCam, on the Simonyi Survey Telescope at Cerro Pachón, Chile.
• The footprint. About 15 square degrees spread over seven separate fields, each observed in six bands, ugrizy, from the optical into the near-infrared.
• Sharpness. The median image sharpness, measured as the width of a star’s blurred image (PSF FWHM), is about 1.14 arcseconds; the best images reach about 0.58 arcseconds. An arcsecond is 1/3,600 of a degree.
• Depth. In the deepest field, the Extended Chandra Deep Field South, stacked images reach magnitude 25.96 in the r band and 26.18 in the g band for point sources detected at 5 sigma.
• Contents. About 2.3 million distinct objects, 1.6 million of them extended rather than point-like, plus 431 Solar System objects, 93 of them new discoveries. The release is about 3.5 terabytes.

How they did it

The products range from raw and calibrated single images to coadds, which stack many exposures to reach fainter objects, and difference images, which subtract a reference image so that anything that changed or moved stands out. Detection catalogs list what the software found. Scientists with Rubin data rights work with DP1 through the Rubin Science Platform, a cloud-based environment built for analyzing very large astronomical data sets.

Why it mattered

DP1 is the first test of the data products that LSST will deliver over a decade. It lets researchers rehearse the analyses the survey was built for: supernova cosmology, the method behind results such as the Dark Energy Survey’s five-year supernova sample; weak lensing; and Solar System discoveries. The 93 new Solar System objects from 48 nights of commissioning data hint at what is coming. Rubin is expected to find many more interstellar visitors like the first one, ‘Oumuamua.

What we know now

The Vera C. Rubin Observatory began its 10-year Legacy Survey of Space and Time in mid-2026 (announced 30 June 2026). Early Data Preview 2 followed on 27 July 2026, and as of October 2026 the full Data Preview 2, with visit-level images and template coadds, is expected between October and December 2026. The date of Data Release 1, based on the survey’s first year, has not been fixed.

Who wrote it

The paper is credited to the Vera C. Rubin Observatory Team, with Tatiana Acero-Cuellar, Emily Acosta and many colleagues. It was posted to arXiv in March 2026 and published in The Astronomical Journal in 2026 (volume 171, article 360).

Read the original

Vera C. Rubin Observatory Team, Acero-Cuellar, T., Acosta, E., et al. (2026). “The Vera C. Rubin Observatory Data Preview 1.” The Astronomical Journal 171, 360. doi:10.3847/1538-3881/ae521f

Free to read: arXiv preprint.