saltishaker 1.0.0

A python package for planning astronomical observations with the South African Large Telescope.

saltshaker

saltshaker is a specialized Python package designed for planning and optimizing astronomical observations with the Southern African Large Telescope (SALT).

[!IMPORTANT] Essential Usage Information:

1. Independent Tool: saltshaker is a community-developed tool.
2. Pre-Planning Only: This package is designed for target screening, survey strategy optimization, and preliminary feasibility checks.
3. Mandatory PIPT Validation: All final visibility windows and observing proposals must be validated and submitted using the official SALT Phase I Proposal Tool.

Because SALT operates with a unique fixed-altitude design (pointing permanently at 37 degrees from the zenith), planning observations requires calculating complex visibility tracks based on Earth's rotation and a physical payload tracker. saltshaker handles these calculations for you, providing high-performance visibility windows, track lengths, and integration with the broader astroplan ecosystem.

Key Features

• Visibility Windows: Calculate exactly when (UTC) a specific star or galaxy will drift into SALT's field of view.
• Track Lengths: Determine how long SALT can track a target before it hits the edge of its operational limits.
• Astroplan Integration: Use SALT-specific tracking and lunar constraints directly within astroplan scheduling.
• Semester Planning: Automatically calculate visibility statistics and nights for entire 6-month SALT observing semesters.
• Singleton Tracking Model: Efficient data loading and high-performance interpolation.

Installation

pip install saltshaker

For development installation:

git clone https://github.com/enzoperesafonso/saltshaker.git
cd saltshaker
pip install .

Quick Start

from saltshaker import get_salt_observer
from astropy.coordinates import SkyCoord
from astropy.time import Time

# Initialize the observer
observer = get_salt_observer()

# Define a target
target = SkyCoord.from_name("Sirius")
time = Time("2026-01-15 12:00:00")

# Get visibility tracks
tracks = observer.get_tracks(target, time)

for track in tracks:
    print(f"Visible from {track.start_time_utc} to {track.end_time_utc}")

Documentation

Full documentation, including a theoretical background on SALT visibility and a "Proposer's Cookbook" of examples, is available at:

https://saltshaker.readthedocs.io/

License

This project is licensed under the MIT License - see the LICENSE file for details.