Amalthea

Amalthea is a fascinating moon in our Solar System that has captured the attention of astronomers and space enthusiasts alike. With a Amalthea radius of 84 km, making it 75.8× smaller than Earth's size, this celestial body presents unique characteristics that distinguish it from other objects in our cosmic neighborhood. Positioned at an average distance of 181,400 km (0.001 AU) from the Sun, Amalthea occupies a significant place in the Solar System's architecture. As a moon, Amalthea demonstrates the incredible diversity of natural satellites that orbit larger celestial bodies throughout our Solar System.

The Amalthea physical characteristics reveal a world of remarkable dimensions and properties. The Amalthea radius measures 84 km, making it 75.8× smaller than Earth's size. The Amalthea mass of 7.50e+18 kg represents 796266.7× smaller than Earth's mass, giving this world substantial gravitational influence. The Amalthea density of 0.857 g/cm³ (6.4× smaller than Earth's density) provides clues about its internal composition, while the surface gravity of 0.02 m/s² (490.5× smaller than Earth's gravity) determines how objects behave on its surface. The low density indicates a composition dominated by lighter elements, characteristic of gas giants or icy bodies.

The Amalthea orbit reveals fascinating details about its journey around the Sun and its relationship to other Solar System objects. The Amalthea orbit has a semimajor axis of 181,400 km (0.001 AU), placing it 824.7× smaller than Earth's distance from the Sun. At its closest approach (perihelion), Amalthea comes within 181,150 km of the Sun, while at its farthest point (aphelion), it reaches 182,840 km, creating a 0.9% variation in solar distance. The Amalthea orbit is nearly circular with an eccentricity of 0.003 (5.6× smaller than Earth's orbital eccentricity), resulting in relatively stable solar heating throughout its year. The Amalthea orbit takes 0.00 hours to complete (63346881.6× smaller than Earth's orbital period), defining the length of its year. The orbital inclination of 0.38° indicates how much the Amalthea orbit is tilted relative to the Solar System's ecliptic plane. This low inclination means Amalthea follows a path very close to the plane where most planets orbit, suggesting a stable formation history.

The Amalthea rotation and axial orientation provide crucial insights into its daily and seasonal cycles, as well as its orbital dynamics. The Amalthea rotation period of 0.00 hours (7206.6× smaller than Earth's rotation period) determines the length of its day. This extremely fast rotation creates intense centrifugal forces and may contribute to the planet's flattened shape. The Amalthea axial tilt of 0° determines the intensity and nature of seasonal variations. With minimal axial tilt, Amalthea experiences virtually no seasonal changes, maintaining relatively constant temperatures throughout its year. The orbital orientation parameters reveal additional details about Amalthea's position in space. The mean anomaly of 0° indicates the planet's current position in its orbit relative to its perihelion. The argument of periapsis of 0° shows how the orbit's orientation changes over time due to gravitational perturbations. The longitude of ascending node of 0° defines the reference point where the orbit crosses the ecliptic plane.

The Amalthea temperature and atmospheric conditions are fundamental to understanding its habitability and environmental characteristics. The Amalthea average temperature of 0.0 K (-273.1 °C) (-459.7°F) provides the baseline for understanding its climate. These extremely cold temperatures make Amalthea inhospitable to life as we know it, with any atmosphere likely frozen solid on the surface. Compared to Earth's average temperature of 15°C (59°F), Amalthea presents a dramatically different thermal environment. Being closer to the Sun than Earth, Amalthea receives more intense solar radiation, contributing to its temperature profile.

The Amalthea escape velocity and shape characteristics reveal important details about its gravitational field and rotational dynamics. The Amalthea escape velocity of 0 m/s determines how easily objects can break free from its gravitational pull. This relatively low escape velocity means that gases and light molecules can easily escape into space, making it difficult for Amalthea to retain a substantial atmosphere. The Amalthea flattening of 0.0000% indicates how much the planet's rotation affects its shape. This minimal flattening suggests a nearly spherical shape, indicating either slow rotation or a very rigid internal structure.