Celestrak_Satellites_over_time.ipynb

Kernel: Python 3

Celestrak - Satellites over time

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Tags: #celestrak #opendata #satellites #analytics #plotly

Author: Dumorya

Last update: 2023-04-12 (Created: 2021-06-11)

Description: This notebook provides a visual representation of the changing number of satellites in Earth's orbit over time.

Input

Import librairies

import pandas as pd
import plotly.express as px
import plotly.graph_objects as go
import numpy as np

Variables

URL = "http://www.celestrak.com/pub/satcat.csv"

Model

Recovery and processing of CSV data

df = pd.read_csv(URL)
df = df[["OPS_STATUS_CODE", "LAUNCH_DATE", "DECAY_DATE"]]
df["DECAY_DATE"] = df["DECAY_DATE"].mask(df["DECAY_DATE"].isnull(), "9999")
df["LAUNCH_DATE"] = df["LAUNCH_DATE"].str[:4].astype(int)
df["DECAY_DATE"] = df["DECAY_DATE"].str[:4].astype(int)
years = df["LAUNCH_DATE"].unique()
inactive = list()
active = list()

for year in years:
    active.append(
        len(
            df[
                (
                    (df["OPS_STATUS_CODE"].isin(["+", "P", "B", "S", "X"]))
                    & (df["LAUNCH_DATE"] <= year)
                )
                | (
                    (df["DECAY_DATE"] > year)
                    & (df["OPS_STATUS_CODE"] == "D")
                    & (df["LAUNCH_DATE"] <= year)
                )
            ].index
        )
    )

    inactive.append(
        len(
            df[
                ((df["OPS_STATUS_CODE"] == "D") & (df["DECAY_DATE"] <= year))
                | ((df["OPS_STATUS_CODE"] == "-") & (df["LAUNCH_DATE"] <= year))
            ].index
        )
    )

Output

Display plot of the number of satellites in space over time

fig = go.Figure(
    data=[
        go.Bar(name="Inactive satellites", x=years, y=inactive),
        go.Bar(name="Active satellites", x=years, y=active),
    ]
)
# Change the bar mode
fig.update_layout(
    title="Number of satellites in space over time",
    xaxis_title="Years",
    yaxis_title="Number of satellites",
    barmode="stack",
)
fig.show()

Source: http://www.celestrak.com/pub/satcat.csv

Display the percentage of inactive VS active satellites from 1957 to now

labels = years
widths = [100 / len(years) for year in years]

active_percentage = list()
inactive_percentage = list()

for index, _ in np.ndenumerate(active):
    total = active[index[0]] + inactive[index[0]]
    active_percentage.append(active[index[0]] / total * 100)
    inactive_percentage.append(inactive[index[0]] / total * 100)

data = {"Inactive": inactive_percentage, "Active": active_percentage}

fig = go.Figure()
for key in data:
    fig.add_trace(go.Bar(name=key, y=data[key], x=years, offset=0))

fig.update_xaxes(range=[years[0], years[-1]])
fig.update_yaxes(range=[0, 100])

fig.update_layout(
    title_text="Percentage of inactive VS active satellites from 1957 to now",
    barmode="stack",
    uniformtext=dict(mode="hide", minsize=10),
)