dustmaps3d 2.2.5

An all-sky 3D dust map based on Gaia and LAMOST.

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dustmaps3d

🌌 An all-sky 3D dust extinction map based on Gaia and LAMOST

📄 Wang et al. (2025), An all-sky 3D dust map based on Gaia and LAMOST
📌 DOI: 10.12149/101620

📦 A Python package for easy access to the 3D dust map
📌 DOI: 10.12149/101619

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📦 Installation

Install via pip:

pip install dustmaps3d

📦 Data File Instructions

⚠️ The package does not include the data file. A ~400MB model file will be automatically downloaded on first use from GitHub or NADC.

🚀 Auto Download Mechanism

• When dustmaps3d() is called, it will try to download data_v3.fits.gz;

• After download, it will automatically extract the file to data_v3.fits and cache it locally;

• On future runs, the file will be read from the local cache without re-downloading.

• ✅ For international users, the primary source is: GitHub Releases

• 🌀 If GitHub download fails, it will automatically fallback to: NADC Data Center

On Chinese systems, the order is reversed — NADC is used as the primary source.

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🌐 What if download fails?

If download fails (e.g. connect timeout), you can manually download and place the file in the cache directory:

1. Visit one of the following links:
   🇨🇳 NADC Data Center (for China)
   🌍 GitHub Releases (global)

2. Download: data_v3.fits.gz

3. Extract to: data_v3.fits

4. Place the extracted file in the local cache directory (the location is printed on first use)

Example path (Windows):
C:\Users\<username>\AppData\Local\dustmaps3d\data_v3.fits

Example path (Linux/macOS):
/home/<username>/.local/share/dustmaps3d/data_v3.fits

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🚀 Usage

from dustmaps3d import dustmaps3d

l = [120.0]
b = [30.0]
d = [1.5]

EBV, dust, sigma, max_d = dustmaps3d(l, b, d)
print(f"EBV: {EBV.values[0]:.4f} [mag]")
print(f"Dust: {dust.values[0]:.4f} [mag/kpc]")
print(f"Sigma: {sigma.values[0]:.4f} [mag]")
print(f"Max distance: {max_d.values[0]:.4f} kpc")

Batch example with FITS:

import numpy as np
from astropy.table import Table
from dustmaps3d import dustmaps3d

data = Table.read('input.fits')   
l = data['l'].astype(float)
b = data['b'].astype(float)
d = data['d'].astype(float)

EBV, dust, sigma, max_d = dustmaps3d(l, b, d)

data['EBV_3d'] = EBV
data['dust'] = dust
data['sigma'] = sigma
data['max_distance'] = max_d
data.write('output.fits', overwrite=True)

⚙️ Tips for Advanced Users

To ensure broad compatibility and ease of use, the official dustmaps3d package makes certain design trade-offs that may come at the cost of peak performance.

If you have higher performance needs — such as support for multi-processing, command-line usage, or faster data loading and I/O — consider using the alternative implementation by SunnyHina:

👉 High-performance version: SunnyHina/dustmaps3d

This version adopts a more modern data loading architecture and is better suited for advanced users working with large-scale or batch processing workflows.

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🧠 Function Description

dustmaps3d(l, b, d, n_process=None)

Estimates 3D dust extinction and related quantities for given galactic coordinates and distances.

Input	Type	Description	Unit
l	np.ndarray	Galactic longitude	degrees
b	np.ndarray	Galactic latitude	degrees
d	np.ndarray	Distance	kpc

Returns:

Output	Type	Description	Unit
EBV	np.ndarray	E(B–V) extinction	mag
dust	np.ndarray	Dust density (d(EBV)/dx)	mag/kpc
sigma	np.ndarray	Estimated uncertainty in E(B–V)	mag
max_d	np.ndarray	Maximum reliable distance	kpc

If d contains NaN, it will be automatically replaced by the maximum reliable distance along that line of sight (max_d).

If the input d exceeds max_d, it indicates the point lies beyond the model's reliable range. The returned values in this case are extrapolated and not guaranteed to be accurate.

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⚡ Performance

• Fully vectorized and optimized with NumPy
• On a modern personal computer, evaluating 100 million stars takes only ~100 seconds

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📜 Citation

If you use this model or the Python package, please cite both:

• Wang, T. (2025), An all-sky 3D dust map based on Gaia and LAMOST. DOI: 10.12149/101620
• dustmaps3d: A Python package for easy access to the 3D dust map. DOI: 10.12149/101619

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🛠️ License

This project is open-source and distributed under the MIT License.

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📫 Contact

If you have any questions, suggestions, or encounter issues using this package,
please feel free to contact the authors via GitHub issues or email.

• Prof. Yuan Haibo: [e-mail]
• Wang Tao: [e-mail]

🔗 GitHub Repository