juliensimon/galileo-jupiter-atmosphere

Galileo Probe Jupiter Atmospheric Profile

Part of the Space Probe & Mission Datasets collection on Hugging Face.

Jupiter atmospheric structure measured by the Galileo Probe Atmospheric Structure Instrument (ASI) during entry and descent on December 7, 1995. The probe entered Jupiter's atmosphere at 6.5 degrees north planetocentric latitude and measured conditions from the stratosphere (1000 km altitude) down to the ~22 bar pressure level (130 km below the 1-bar reference).

Currently 686 measurements: 386 from the entry phase (upper atmosphere) and 300 from the parachute descent phase.

Dataset description

The Galileo Probe was the first (and so far only) spacecraft to directly sample a giant planet's atmosphere. Released from the Galileo orbiter, it entered Jupiter's atmosphere at ~47 km/s and deployed a parachute at ~23 km above the 1-bar level. The Atmospheric Structure Instrument (ASI) measured temperature, pressure, and density throughout the entry and descent phases.

The entry phase covers the upper atmosphere (stratosphere and upper troposphere, 1000 km down to ~23 km altitude) where measurements are derived from probe deceleration. The descent phase covers the lower troposphere (17 km down to ~-133 km, i.e., from 0.4 bar to ~22 bar) using direct temperature and pressure sensors under parachute.

Schema

Column	Type	Description
phase	string	Measurement phase: "entry" (upper atmosphere) or "descent" (lower atmosphere)
time_s	float64	Time from minor frame 0 (seconds)
altitude_km	float64	Altitude above the 1-bar pressure level (km; negative = below 1-bar)
pressure_bar	float64	Ambient atmospheric pressure (bar)
pressure_mbar	float64	Ambient atmospheric pressure (millibar) — entry phase only
temperature_k	float64	Atmospheric temperature (Kelvin)
density_kg_m3	float64	Atmospheric mass density (kg/m^3)
mean_molecular_weight_amu	float64	Mean molecular weight (AMU) — entry phase only
cp_over_cv	float64	Ratio of specific heats — entry phase only
gas_constant_j_kg_k	float64	Specific gas constant R (J/kg/K) — entry phase only
gravity_m_s2	float64	Local gravitational acceleration (m/s^2) — descent phase only
descent_velocity_m_s	float64	Probe descent velocity (m/s) — descent phase only
temperature_gradient_k_km	float64	Temperature lapse rate dT/dz (K/km) — descent phase only
velocity_km_s	float64	Probe velocity relative to atmosphere (km/s) — entry phase only
flight_path_angle_deg	float64	Flight path angle relative to atmosphere (degrees) — entry phase only
latitude_deg	float64	Planetocentric latitude (degrees) — entry phase only
longitude_deg	float64	System III west longitude (degrees) — entry phase only

Quick stats

• 686 atmospheric measurements (entry + descent)
• Altitude range: 1029 km to -133 km (above 1-bar level)
• Pressure range: 9.66e-10 bar to 22.05 bar
• Temperature range: 107 K to 904 K
• Date: December 7, 1995

Usage

from datasets import load_dataset

ds = load_dataset("juliensimon/galileo-jupiter-atmosphere", split="train")
df = ds.to_pandas()

# Full temperature profile
import matplotlib.pyplot as plt
plt.plot(df["temperature_k"], df["altitude_km"])
plt.xlabel("Temperature (K)")
plt.ylabel("Altitude above 1-bar (km)")
plt.title("Jupiter Temperature Profile — Galileo Probe")
plt.grid(True)
plt.show()

# Descent phase only — pressure vs temperature
descent = df[df["phase"] == "descent"]
plt.semilogy(descent["temperature_k"], descent["pressure_bar"])
plt.xlabel("Temperature (K)")
plt.ylabel("Pressure (bar)")
plt.gca().invert_yaxis()
plt.title("Jupiter T-P Profile (Descent Phase)")
plt.show()

# Entry phase — upper atmosphere density
entry = df[df["phase"] == "entry"]
plt.semilogy(entry["density_kg_m3"], entry["altitude_km"])
plt.xlabel("Density (kg/m^3)")
plt.ylabel("Altitude (km)")
plt.title("Jupiter Upper Atmosphere Density")
plt.show()

Data source

NASA PDS Atmospheres Node — Galileo Probe ASI. Data from the Atmospheric Structure Instrument (ASI) on the Galileo Probe, archived by the Planetary Data System. Reference: Seiff et al. (1998), "Thermal structure of Jupiter's atmosphere near the edge of a 5-micron hot spot in the north equatorial belt", J. Geophys. Res., 103(E10), 22857-22889.

Update schedule

Static dataset (one-time upload). The Galileo Probe entered Jupiter on December 7, 1995.

Related datasets

• deep-space-probes — Voyager 1/2 and Pioneer 10/11 merged hourly data
• jupiter-magnetosphere — Juno magnetometer data at Jupiter

Pipeline

Source code: juliensimon/space-datasets

Support

If you find this dataset useful, please give it a ❤️ on the dataset page and share feedback in the Community tab! Also consider giving a ⭐ to the space-datasets repo.

Citation

@dataset{galileo_jupiter_atmosphere,
  author = {Simon, Julien},
  title = {Galileo Probe Jupiter Atmospheric Profile},
  year = {2026},
  publisher = {Hugging Face},
  url = {https://huggingface.co/datasets/juliensimon/galileo-jupiter-atmosphere},
  note = {Based on NASA/PDS Galileo Probe Atmospheric Structure Instrument (ASI) data. Original PI: A. Seiff (NASA Ames)}
}

License

CC-BY-4.0