ASTRA-Core v3.2.0 (Autonomous Space Traffic Risk Analyzer) 🛰️

PyPI - Version License

The High-Performance Mathematical Foundation for Space Situational Awareness.

📖 Comprehensive User Guide & API Reference: Available on Read The Docs

ASTRA-Core is a rigorous, C-accelerated Python astrodynamics engine powering the ASTRA ecosystem. Designed for aerospace engineers, researchers, and developers, it solves the complex, heavy-lifting astrodynamics required to track thousands of orbital objects simultaneously, predict collisions, and monitor congestion across all orbital regimes.

🧠 Want to learn how the math works? Check out our educational guide: KNOWMORE.md to understand TLEs, SGP4, Sweep-and-Prune, and Collision Probabilities!

currently working on optimization and irregularities of earth's surface.

🚀 Key Features

High-Fidelity Cowell Method Propagation: Integrate the exact equations of motion (DOP853) with an elite force model evaluating $J_2-J_4$ zonal harmonics, Atmospheric Drag, and Solar/Lunar third-body perturbations.
Maneuver Modeling & 7-DOF Flight Dynamics: Formulate exact finite continuous burns using attitude-steered Dynamic VNB/RTN direction combinations with coupled mass expulsion tracking (Tsiolkovsky equation) directly in the integration loop.
Operations-Grade Physical Truth Pipelines: Ditch analytical physics approximations for real-world automated feeds: JPL DE421 (Sub-arcsecond Moon/Sun Ephemerides) and CelesTrak Space Weather (F10.7/Kp data scaling Jacchia-class empirical atmospheric density models).
Spatial KD-Tree Conjunction Analysis: Implements a highly optimized, persistent 3D $O(n \log n)$ Spatial KD-Tree index to uniquely isolate candidate colliding trajectories across massive time integrations.
Continuous Time of Closest Approach (TCA): Uses interpolations to find the exact millisecond of closest approach, coupled with Dynamic LVLH Attitude Modes to project satellite cross-sections precisely at the impact geometry.
True Probability of Collision ($P_c$): Executes a true 6D minimum-distance Monte Carlo probability distribution across colliding volumes, propagated physically via a full 6x6 State Transition Matrix built natively from numerical force Jacobians.
Official Data Integration: Directly parses active catalogs from CelesTrak and reads official U.S. Space Force CDM (Conjunction Data Message) XMLs.
Pass Predictions: Calculate topocentric geometry to find when a satellite will be visible from a specific ground station.

📦 Installation

Available natively on PyPI for immediate use in your Python projects:

pip install astra-core-engine

For development & contribution: If you want to modify the source code or run the test suite:

git clone https://github.com/ISHANTARE/ASTRA.git
cd ASTRA
pip install -e .[test]

💻 Technical Quickstart

Here is how you can use ASTRA-Core to fetch live satellite data and predict close calls within minutes.

1. Fetching Data and Mass Propagation

import astra
import numpy as np

# 1. Fetch live TLEs from CelesTrak
print("Downloading live active satellite catalog...")
active_catalog = astra.fetch_celestrak_active()

# 2. Filter for Low Earth Orbit (LEO) only
objects = [astra.make_debris_object(tle) for tle in active_catalog]
leo_only = astra.filter_altitude(objects, min_km=200, max_km=2000)

# 3. Propagate 10,000+ objects simultaneously across the next 2 hours
tles = [obj.tle for obj in leo_only]
time_steps = np.arange(0, 120, 5.0) # Minutes
times_jd = leo_only[0].tle.epoch_jd + (time_steps / 1440.0)
trajectories = astra.propagate_many(tles, times_jd)

2. Detecting Conjunctions (Collisions)

# Scan for any satellites coming within 5km of each other
events = astra.find_conjunctions(
    trajectories, 
    times_jd=leo_only[0].tle.epoch_jd + (time_steps / 1440.0), 
    elements_map={obj.tle.norad_id: obj for obj in leo_only}, 
    threshold_km=5.0
)

for event in events:
    print(f"THREAT: SAT {event.primary_id} vs SAT {event.secondary_id}")
    print(f"Distance: {event.min_distance_km:.2f} km at TCA: {event.tca}")

📚 Library API Cheatsheet (Exposed Functions)

ASTRA-Core natively exposes all top-level functions directly from astra.__init__. Here are all the callable functions with a syntax implementation example for each:

Data Acquisition & Parsing

fetch_celestrak_active(): catalog = astra.fetch_celestrak_active()
fetch_celestrak_comprehensive(): catalog = astra.fetch_celestrak_comprehensive()
fetch_celestrak_group(group): gnss = astra.fetch_celestrak_group("gps-ops")
parse_cdm_xml(filepath): cdm = astra.parse_cdm_xml("warning.xml")
load_tle_catalog(filepath): tles = astra.load_tle_catalog("catalog.txt")
parse_tle(name, l1, l2): tle = astra.SatelliteTLE.from_strings("1 255...", "2 255...", name="ISS")
validate_tle(l1, l2): is_valid = astra.validate_tle(line1, line2)

Filtering & Debris Processing

make_debris_object(tle): obj = astra.make_debris_object(tle)
filter_altitude(objs, min, max): leo = astra.filter_altitude(objects, 200, 2000)
filter_region(objs, lat, lon): overhead = astra.filter_region(objects, lat_bounds, lon_bounds)
filter_time_window(objs, t1, t2): visible = astra.filter_time_window(objects, start_jd, end_jd)
apply_filters(objs, config): subset = astra.apply_filters(objects, filter_config)
catalog_statistics(objs): stats_dict = astra.catalog_statistics(objects)

High-Performance Propagation & Orbit Math

propagate_cowell(state, duration_s, ...): trajectory = astra.propagate_cowell(initial_state, duration_s=7200, dt_out=60.0)
propagate_many(tles, times_jd): traj_map = astra.propagate_many([tle1, tle2], times_jd)
propagate_many_generator(tles, times_jd): for jd_chunk, traj_chunk in astra.propagate_many_generator(tles, times_jd): pass
propagate_orbit(tle, epoch, t_min): state = astra.propagate_orbit(tle, tle.epoch_jd, 10.0)
propagate_trajectory(tle, t1, t2, step): times_jd, pos = astra.propagate_trajectory(tle, start_jd, end_jd, step_minutes=5.0)
ground_track(positions, times): lat_lon_alt = astra.ground_track(teme_pos, times_jd)
orbital_elements(pos, vel): elements = astra.orbital_elements(r, v)
orbit_period(semi_major_axis): period_s = astra.orbit_period(a_km)

Conjunctions & Covariance (O(n log n) cKDTree)

find_conjunctions(...): events = astra.find_conjunctions(trajs, times_jd, obj_map, 5.0, 50.0)
closest_approach(...): tca, dist = astra.closest_approach(traj_a, traj_b, times)
distance_3d(pos1, pos2): d = astra.distance_3d(r1, r2)
compute_collision_probability(...): pc = astra.compute_collision_probability(r_rel, v_rel, cov)
compute_collision_probability_mc(...): pc = astra.compute_collision_probability_mc(r_rel, v_rel, cov, 10000)
estimate_covariance(...): cov = astra.estimate_covariance(tle, position, velocity)
propagate_covariance_stm(...): cov_t = astra.propagate_covariance_stm(cov_0, initial_state, t_span)

Visibility & Ground Stations

visible_from_location(...): elevations = astra.visible_from_location(pos, times, observer)
passes_over_location(...): passes = astra.passes_over_location(tle, observer, t_start, t_end)

High-Fidelity Physics & Maneuvers

projected_area_m2(dim, quat, v_rel): area = astra.projected_area_m2((1,2,3), q, v_dir)
thrust_acceleration_inertial(...): acc = astra.thrust_acceleration_inertial(burn, mass, t, state)
rotation_vnb_to_inertial(pos, vel): matrix = astra.rotation_vnb_to_inertial(r, v)
rotation_rtn_to_inertial(pos, vel): matrix = astra.rotation_rtn_to_inertial(r, v)
frame_to_inertial(frame, pos, vel): matrix = astra.frame_to_inertial(ManeuverFrame.VNB, r, v)
validate_burn(burn): is_valid = astra.validate_burn(burn_dataclass)

Space Weather & Data Pipelines

get_space_weather(jd): f107, f107a, ap = astra.get_space_weather(t_jd)
load_space_weather(filepath): astra.load_space_weather("SW-All.csv")
atmospheric_density_empirical(...): rho = astra.atmospheric_density_empirical(alt, f107, f107a, ap)
sun_position_de(jd): r_sun = astra.sun_position_de(t_jd)
moon_position_de(jd): r_moon = astra.moon_position_de(t_jd)

Top-Level Utilities

haversine_distance(l1, ln1, l2, ln2): dist_km = astra.haversine_distance(34.0, -118.0, 40.0, -74.0)
convert_time(time_val, to_format): jd = astra.convert_time("2026-01-01T00:00:00Z", "jd")
plot_trajectories(trajs, events): fig = astra.plot_trajectories(trajectories, conjunction_events)

🚀 Examples

Want to see the math in action? Check out the examples/ directory included in the repository source code:

examples/01_basic_conjunctions.py - Full collision prediction pipeline using cKDTree.
examples/02_visualize_swarm.py - 3D trajectory rendering of LEO satellite constellations.
examples/03_ground_station_visibility.py - Predict when satellites will pass over your coordinates.

📝 How to Cite ASTRA

If you use ASTRA-Core in an academic paper, research project, or commercial product, please use the following BibTeX entry to provide attribution:

@software{Tare_ASTRA_2026,
  author = {Tare, Ishan},
  title = {ASTRA: Autonomous Space Traffic Risk Analyz

ASTRA

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