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The international FLAMINGO project (Full-hydro Large-scale structure simulations with All-sky Mapping for the Interpretation of Next Generation Observations) has just released one of the biggest cosmological simulation datasets in history — more than 2.5 petabytes of data, roughly equivalent to 500,000 HD movies.

Led by researchers from Leiden University and the Virgo Consortium, FLAMINGO simulates the full evolution of the Universe from the Big Bang to the present day (13.8 billion years). Unlike traditional dark-matter-only simulations, it includes full hydrodynamics with:

- Ordinary (baryonic) matter — stars, galaxies, gas, cooling, star formation, supernovae, and AGN feedback.

- Dark matter.

- Massive neutrinos (modeled explicitly with particles).

- Dark energy.

Key specs of the flagship runs:

- Largest box: **2.8 Gpc** (~9 billion light-years) on a side.

- Up to **300 billion particles** (3 × 10¹¹).

- Three resolution levels, with the fiducial models carefully calibrated (using machine learning) to match the observed galaxy stellar mass function and cluster gas fractions at low redshift.

- Multiple variations exploring different feedback models, stellar mass functions, cosmologies, and neutrino masses.

- Full-sky lightcone outputs (HEALPix maps) for up to 8 observers, plus snapshots, halo/galaxy catalogues, and power spectra.

The entire suite includes 22 hydrodynamical + 16 gravity-only simulations. It was run on the COSMA 8 supercomputer (DiRAC, Durham University) using the highly efficient SWIFT code, consuming over 50 million CPU hours.

The FLAMINGO project consumed more than 50 million CPU hours (also called core-hours or processor hours) in total.

This figure is the most commonly cited value across official announcements from Durham University, Leiden University, and the Virgo Consortium for the full suite of simulations (hydrodynamical + dark-matter-only runs).

Key Details:

- The simulations were run on the COSMA 8 supercomputer (part of the DiRAC facility at Durham University, UK).

- The code used, SWIFT, scaled efficiently to 30,000–65,000 CPUs simultaneously.

- One of the largest flagship runs (L2p8_m9, the 2.8 Gpc box) took approximately 31 million core-hours and ran for about 42 days on ~30,000 CPUs.

- Another high-resolution run (L1_m8) required around 17 million core-hours.

- The full project (including all variations, calibrations, and the 2026 data release with >2.5 petabytes of data) pushed the total well above 50 million CPU hours.

For context, this is equivalent to many centuries of computing time on a single high-end CPU — only possible thanks to massive parallelization on a top-tier supercomputer.

Why it matters:

FLAMINGO bridges small-scale galaxy formation physics with enormous cosmic volumes needed for precision cosmology. It helps interpret data from telescopes like JWST, Euclid, DESI, and LSST, test models of structure formation, quantify baryonic effects on the matter power spectrum (up to ~20% suppression), and address tensions in cosmology.

The full dataset is publicly available (with selective download tools because of its massive size). Check the official site and the 2026 data release paper for details.

Links:

- Official website: https://flamingo.strw.leidenuniv.nl/

- Data Release Paper (arXiv 2026): https://arxiv.org/abs/2604.24324

- Main Project Paper (2023): https://arxiv.org/abs/2306.04024

This is a new golden age for computational cosmology. What do you think — will simulations like this finally help solve the Hubble tension or other big questions?!

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