Anahata

1. About Anahata

Anahata is an open-source, browser-based application that transforms real stellar oscillation data into sound. Using photometric light curves from space-based telescopes — primarily NASA TESS, NASA Kepler / K2, and ESA Gaia — the app extracts pulsation frequencies and maps them to musical pitches and timbres, enabling users to listen to the natural rhythms of stars.

The name Anahata (Sanskrit: अनाहत) refers to the unstruck, cosmic sound — a fitting metaphor for signals that travel across light-years before being made audible here.

2. Terms of Use

2.1 Acceptance

By accessing or using Anahata (the web application, any hosted instance, or the source code), you agree to comply with these terms. If you do not agree, please discontinue use.

2.2 Permitted Use

• Personal, educational, and non-commercial research use of the application.
• Artistic or musical projects that credit Anahata and the underlying data sources.
• Running your own instance of Anahata on personal or institutional infrastructure.
• Contributing to the project under the terms of the project license (see Section 6).

2.3 Prohibited Use

• Using Anahata to make medical, astrological, or other non-scientific claims about the stars or users.
• Redistributing modified versions without complying with the applicable open-source license.
• Automated mass-querying of third-party data APIs (MAST, Gaia Archive) via the Starproc Python app in violation of their respective terms of service.
• Presenting sonified output as scientifically precise measurements without appropriate caveats.

2.4 Modification of Terms

These terms may be updated at any time. The date at the top of this page reflects the most recent revision. Continued use after an update constitutes acceptance of the revised terms.

3. Data Sources & Attribution

The Anahata and Astral web tools are fully offline-capable and do not initiate any communication with MAST, STScI, or ESA servers. All astronomical data displayed or played back by these tools has been pre-processed and bundled with the application.

External data is fetched only when you explicitly run the Starproc Python app (astral/starproc/app.py). This local server exposes a REST API (POST /api/lightcurve, POST /api/frequencies) that you call to pull TESS or Kepler / K2 light curves for a star of your choice and compute its oscillation frequencies. Those results are saved locally and can then be loaded into Anahata / Astral for sonification.

3.1 NASA / TESS (MAST)

When the Starproc app is running, TESS light curves are retrieved from the Mikulski Archive for Space Telescopes (MAST) via lightkurve. TESS data is publicly available and provided by NASA under an open data policy. Publications or public projects using TESS data should cite the relevant mission and instrument papers. Targets are auto-resolved: any TIC ... identifier is routed to the TESS archive.

3.2 NASA / Kepler & K2 (MAST)

Kepler and K2 light curves are also retrieved from MAST via lightkurve. Both missions' data are publicly available under NASA's open data policy. Any KIC ... identifier is auto-resolved to the Kepler archive; K2 targets use their EPIC identifiers. Publications using Kepler or K2 data should cite the relevant mission papers and the specific data release used.

3.3 ESA Gaia

Star catalog data (positions, proper motions, parallaxes) is sourced from the ESA Gaia Archive. Use of Gaia data is subject to the Gaia data license. Please acknowledge ESA Gaia in any derivative work.

3.4 Suggested Citation

4. Audio & Scientific Content

4.1 Nature of the Sonification

The sounds produced by Anahata are an artistic and scientific mapping of stellar pulsation frequencies into the audible range. The raw oscillation frequencies of stars (typically micro-hertz to milli-hertz) are scaled by factors of millions to reach human hearing range. The resulting audio is a faithful representation of the relative frequency ratios of a star's oscillation spectrum, not a literal sound from space.

4.2 Synthesis Engine

Audio synthesis is performed locally using SuperCollider and/or FoxDot running on the user's machine. No audio is streamed from or recorded by Anahata servers.

4.3 Copyright of Output

The underlying stellar data is in the public domain (NASA/ESA open data). The synthesized audio compositions you create with Anahata are your own; however, if you publish or distribute them, please credit the data sources and Anahata as the synthesis tool.

5. Privacy Policy

5.1 Data We Do Not Collect

Anahata is a client-side Progressive Web App (PWA). In its default configuration it does not:

• Collect or store any personally identifiable information.
• Require account registration or login.
• Use tracking pixels, advertising SDKs, or third-party analytics.
• Transmit user data to Anahata's servers.

5.2 Third-Party API Requests

The Anahata and Astral web tools do not contact MAST, STScI, ESA, or any external server. No star queries are issued by the browser application itself.

External network requests occur only when you run the Starproc Python app locally and call its API to download stellar data. In that case, your machine connects directly to MAST (for TESS, Kepler, or K2 data) on your behalf. Those requests include your IP address as a standard part of the HTTP protocol. Please review the privacy policies of STScI / MAST and ESA for details on how they handle server logs.

5.3 Local Storage

Anahata may use browser localStorage or sessionStorage to cache star lists and user preferences. This data never leaves your device and can be cleared at any time through your browser settings.

5.4 Service Worker & Offline Cache

The PWA service worker (sw.js) caches app assets locally to enable offline use. No personal data is included in this cache. You can unregister the service worker and clear the cache via your browser's developer tools.

6. Open Source & Licensing

6.1 Application License

Anahata is open-source software. Please refer to the LICENSE file in the repository for the exact terms governing use, modification, and distribution of the source code.

6.2 Third-Party Libraries

The following key third-party components are used in Anahata. Each is subject to its own license:

• lightkurve — MIT License — NASA / lightkurve contributors
• Aladin Lite — BSD / CDS License — Centre de Données astronomiques de Strasbourg
• SuperCollider — GPL v2 or later — SuperCollider contributors
• FoxDot — MIT License — Ryan Kirkbride
• astropy — BSD 3-Clause — The Astropy Project
• FastAPI / Uvicorn — MIT License — Sebastián Ramírez & contributors

6.3 Contributing

Contributions are welcome. By submitting a pull request or patch, you agree that your contribution may be distributed under the same license as the project. Please read the project's contribution guidelines in the repository before submitting.

7. Disclaimers & Limitations of Liability

7.1 No Warranty

Anahata is provided "as is", without warranty of any kind, express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, or non-infringement. The authors make no guarantee that the application will be available, error-free, or produce scientifically accurate results at all times.

7.2 Limitation of Liability

To the fullest extent permitted by applicable law, the Anahata authors and contributors shall not be liable for any indirect, incidental, special, consequential, or exemplary damages arising from your use of the application or any data produced by it, even if advised of the possibility of such damages.

7.3 External Links

Links to third-party websites (NASA, ESA, etc.) are provided for convenience. Anahata does not endorse and is not responsible for the content, privacy practices, or availability of external sites.

7.4 Availability

Third-party data APIs (MAST for TESS / Kepler / K2, and the Gaia Archive) may impose rate limits, undergo maintenance, or change their access policies without notice. Anahata cannot guarantee uninterrupted access to external data.

9. Contributing a Star

Anahata's star library grows through community contributions. If you have discovered an interesting pulsating star you'd like to see included in the app, there are two ways to submit it:

9.1 Merge Request (preferred)

Open a merge / pull request on the main repository and include a JSON file named after the star (e.g. TIC_123456789.json) placed in astral/starproc/results/. The file should follow the existing result schema and contain at minimum:

• Star name / TIC identifier
• Coordinates — right ascension & declination (J2000, decimal degrees)
• Distance — in parsecs (from Gaia parallax or literature)
• Frequency list — one entry per detected oscillation mode, each with:
  • frequency — in µHz or mHz
  • amplitude — relative or normalised
  • phase — in radians or degrees (state which)

9.1.1 Example JSON

Below is a minimal example based on TIC 10053527. Only the first three frequency entries are shown for brevity — the full file will contain all detected modes.

{
  "name":         "TIC 10053527",
  "ra":           124.231211,
  "dec":          41.336418,
  "dist_pc":      500.956,
  "scale_factor": 10000.0,
  "info":         "",
  "frequencies": {
    "freq":  [ 5475.003, 4942.476, 4393.085, /* ... */ ],
    "amp":   [ 0.04762,  0.11441,  0.07907,  /* ... */ ],
    "phase": [ 0.82491,  0.97229,  0.46922,  /* ... */ ]
  }
}

9.2 Email Submission

If you are not familiar with Git, you can email the star details directly to sachusanjayan@gmail.com with the subject line "Anahata Star Submission: <Star Name>". Please include:

• Star name and/or TIC / Gaia DR3 identifier
• Coordinates (RA & Dec, J2000)
• Distance in parsecs
• Detected frequencies, amplitudes, and phases (a CSV or JSON attachment is ideal)
• Data source (e.g. TESS sector numbers, Kepler quarter)

Submitted stars will be reviewed for scientific plausibility before being added to the bundled star library. You will be credited in the repository and, where applicable, in the application's star metadata.

8. Contact

For questions about these terms, data usage, or the project in general, please open an issue in the Anahata GitHub repository or reach out via the contact information listed there.