oplanet 1.2.0

Lightweight Python wrapper around the NASA Exoplanet Archive.

oplanet

Lightweight Python wrapper around the NASA Exoplanet Archive with practical helpers for stellar aliases, photometry, and system/planet properties.

This package is built to make exoplanet metadata easier to use in notebooks and scripts by exposing a simple object API and automatically selecting the most reliable published values.

NSystem is exported at package level, so you can import it directly with from oplanet import NSystem.

What it is

oplanet wraps data from:

• NASA Exoplanet Archive
• Simbad / Vizier utilities for star aliases, coordinates, and photometry

For parameters with multiple entries in the archive, it chooses the best measurement by preferring rows with the smallest uncertainty bars (when available), with fallback to limits when no direct value exists.

Measurement-return convention used by NSystem/NStar/NPlanet properties:

• Standard measurement: [value, err_pos, err_neg]
• No direct measurement but limits exist: [nan, limit_upper, limit_lower]

Installation

From pip (recommended)

pip install oplanet

From GitHub

pip install "git+https://github.com/ProfesseurShadoko/oplanet.git"

From source

git clone https://github.com/ProfesseurShadoko/oplanet.git
cd oplanet
python -m venv .venv
source .venv/bin/activate
pip install .

Requirements

Dependencies are listed in requirements.txt:

• oakley
• numpy
• pandas
• astroquery
• astropy
• scipy
• matplotlib

Quick examples

For a guided walkthrough with explanations and runnable cells, see examples.ipynb.

1. Resolve star names and aliases

from oplanet import parse_star_name, get_star_aliases

print(parse_star_name("TOI 1478"))
print(get_star_aliases("TOI 1478"))

2. Explore a system, its star, and its planets

from oplanet import NSystem

system = NSystem("LHS 1140")

print(system.star_name)
print(system.n_planets)

# Returns [value, err1, err2] when available,
# or [nan, upper_limit, lower_limit] when only limits exist
print(system.distance_pc)
print(system.star.age_myr)

print(system.b.mass_mjup)
print(system.b.orbital_period_yrs)

3. One-line import for common API

from oplanet import NSystem, parse_star_name, get_star_aliases, get_photometry_jy

4. Get stellar photometry at a wavelength

from oplanet import get_photometry_jy

flux_jy = get_photometry_jy("LHS 1140", 11.56)
print(flux_jy)

5. Pretty-print helpers (display and print_column)

from oplanet import NSystem

system = NSystem("LHS 1140")

# Human-readable summary of system properties
system.display()

# Human-readable summary for star and a planet
system.star.display()
system.b.display()

# Print raw dataframe values for a specific archive column
system.print_column("st_age")

Returned values

Most numeric property getters in the object API return a NumPy array with 3 entries:

• value: best selected value
• err_pos: positive uncertainty
• err_neg: negative uncertainty

When no direct value is available and only limits are present, the returned array is:

• nan, limit_upper, limit_lower

Examples:

system = NSystem("LHS 1140")

age = system.star.age_myr
distance = system.distance_pc

print(age)       # e.g. [value, err_pos, err_neg] or [nan, upper, lower]
print(distance)  # same convention

Data behavior

On import, the loader keeps a local CSV cache in oplanet/data, removes older archive snapshots, and refreshes stale files automatically.

Notes

• Internet access is needed for Simbad/Vizier queries and first-time archive download.
• This repository is currently source-first (requirements-driven), not a published PyPI package.
• The support for exoplanet.eu will be added once the database becomes more reliable and code friendly.

License

MIT