# Observations and scientific figures

Telescope imagery comes from official ESA/Hubble, ESA/Webb, ESO and Chandra releases. It is not AI-generated. The Bullet Cluster composite also contains a clearly labeled lensing-inferred mass overlay. Pixel files are unmodified publisher JPEGs. The observation workbench preserves full frames; some images on the expansion homepage may be cropped by display framing.

| Local file | Object / original | Required credit |
| --- | --- | --- |
| cosmic-field.jpg | [CLASS B1608+656, heic1408a](https://esahubble.org/images/heic1408a/) | NASA, ESA |
| cepheid-rs-puppis.jpg | [RS Puppis, heic1323a](https://esahubble.org/images/heic1323a/) | NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration. Acknowledgment: H. Bond (STScI and Penn State University). |
| supernova-1994d.jpg | [SN 1994D, opo9919i](https://esahubble.org/images/opo9919i/) | NASA/ESA, The Hubble Key Project Team and The High-Z Supernova Search Team |

Usage: [ESA/Hubble terms](https://esahubble.org/copyright/), [Creative Commons Attribution 4.0](https://creativecommons.org/licenses/by/4.0/). Full credits appear beside the images on the website. No endorsement is implied.

Direct downloads:

- https://cdn.esahubble.org/archives/images/screen/heic1408a.jpg
- https://cdn.esahubble.org/archives/images/screen/heic1323a.jpg
- https://cdn.esahubble.org/archives/images/screen/opo9919i.jpg

`likelihood-contours.svg`, `redshift-sensitivity.svg`, `model-comparison.svg`, `expansion-history.svg` and `hubble-diagram.png` are original, deterministic scientific plots produced by the analysis scripts. The first three use the pinned Pantheon+ / SH0ES results; expansion history compares explicitly stated analytic models. Telescope images illustrate the astrophysical objects, not fitted pixels.

## Observation workbench (release 3.1)

Third-party image terms apply separately from the software MIT license. Full credits are shown next to the active image. No observatory endorsement is implied.

### Norma Cluster · Abell 3627 / Hubble · galaxy detail

- Local file: `observations/norma-hubble.jpg`
- Source: [potw1302a](https://esahubble.org/images/potw1302a/)
- Credit: ESA/Hubble & NASA
- Usage: [CC BY 4.0](https://esahubble.org/copyright/)
- [Publisher JPEG](https://cdn.esahubble.org/archives/images/screen/potw1302a.jpg); no pixel modifications.

### Norma Cluster · Abell 3627 / ESO · wider environment

- Local file: `observations/norma-eso.jpg`
- Source: [eso9954c](https://www.eso.org/public/images/eso9954c/)
- Credit: ESO
- Usage: [CC BY 4.0](https://www.eso.org/public/outreach/copyright/)
- [Publisher JPEG](https://cdn.eso.org/images/screen/eso9954c.jpg); no pixel modifications.

### Pandora's Cluster · Abell 2744 / JWST · infrared

- Local file: `observations/pandora-webb.jpg`
- Source: [weic2305a](https://esawebb.org/images/weic2305a/)
- Credit: NASA, ESA, CSA, I. Labbe (Swinburne University of Technology), R. Bezanson (University of Pittsburgh), A. Pagan (STScI)
- Usage: [CC BY 4.0](https://esawebb.org/copyright/)
- [Publisher JPEG](https://cdn.esawebb.org/archives/images/screen/weic2305a.jpg); no pixel modifications.

### Pandora's Cluster · Abell 2744 / Hubble · optical + infrared

- Local file: `observations/pandora-hubble.jpg`
- Source: [heic1401a](https://esahubble.org/images/heic1401a/)
- Credit: NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team (STScI).
- Usage: [CC BY 4.0](https://esahubble.org/copyright/)
- [Publisher JPEG](https://cdn.esahubble.org/archives/images/screen/heic1401a.jpg); no pixel modifications.

### Bullet Cluster · 1E 0657−56 / Light + inferred mass

- Local file: `observations/bullet-composite.jpg`
- Source: [chandra-bullet-2025-composite](https://www.chandra.harvard.edu/photo/2025/bullet/index.html)
- Credit: X-ray: NASA/CXC/SAO; Near-infrared: NASA/ESA/CSA/STScI; Image processing: NASA/STScI/J. DePasquale
- Usage: [Publisher image-use policy; see source and credit](https://www.chandra.harvard.edu/photo/image_use.html)
- [Publisher JPEG](https://www.chandra.harvard.edu/photo/2025/bullet/bullet.jpg); no pixel modifications.

### Bullet Cluster · 1E 0657−56 / JWST · starlight

- Local file: `observations/bullet-webb.jpg`
- Source: [chandra-bullet-2025-nircam](https://www.chandra.harvard.edu/photo/2025/bullet/more.html)
- Credit: X-ray: NASA/CXC/SAO; Near-infrared: NASA/ESA/CSA/STScI; Image processing: NASA/STScI/J. DePasquale
- Usage: [Publisher image-use policy; see source and credit](https://www.chandra.harvard.edu/photo/image_use.html)
- [Publisher JPEG](https://www.chandra.harvard.edu/photo/2025/bullet/bullet_nircam.jpg); no pixel modifications.

### Bullet Cluster · 1E 0657−56 / Chandra · hot gas

- Local file: `observations/bullet-xray.jpg`
- Source: [chandra-bullet-2025-xray](https://www.chandra.harvard.edu/photo/2025/bullet/more.html)
- Credit: X-ray: NASA/CXC/SAO; Near-infrared: NASA/ESA/CSA/STScI; Image processing: NASA/STScI/J. DePasquale
- Usage: [Publisher image-use policy; see source and credit](https://www.chandra.harvard.edu/photo/image_use.html)
- [Publisher JPEG](https://www.chandra.harvard.edu/photo/2025/bullet/bullet_xray.jpg); no pixel modifications.

### SN 1994D · NGC 4526 / Hubble · SN 1994D

- Local file: `supernova-1994d.jpg`
- Source: [opo9919i](https://esahubble.org/images/opo9919i/)
- Credit: NASA/ESA, The Hubble Key Project Team and The High-Z Supernova Search Team
- Usage: [CC BY 4.0](https://esahubble.org/copyright/)
- [Publisher JPEG](https://cdn.esahubble.org/archives/images/screen/opo9919i.jpg); no pixel modifications.

The machine-readable [manifest](../data/observations.json) pins every image checksum and dimension. Inferred overlays are labeled as such. Different crops and fields are not treated as registered measurements.

## Published Laniakea reconstruction (release 3.2)

- File: `observations/laniakea-boundaries.jpg`
- Credit: R. Brent Tully (U. Hawaii) et al., SDvision, DP, CEA/Saclay.
- [Distribution and CC BY 4.0 declaration](https://commons.wikimedia.org/wiki/File:LaniakeaBoundaries.jpg), [license](https://creativecommons.org/licenses/by/4.0/), [NASA APOD source](https://apod.nasa.gov/apod/ap140910.html).
- [Original paper](https://doi.org/10.1038/nature13674). This is a rendered published reconstruction, not a telescope photograph or an analysis performed by this repository.
- No pixel modifications. File checksum, dimensions and limitations are in [reconstruction.json](../data/reconstruction.json). No endorsement is implied.