Helene

Helene is a fascinating moon in our Solar System that has captured the attention of astronomers and space enthusiasts alike. With a Helene radius of 17.6 km, making it 362.0× 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 377,396 km (0.003 AU) from the Sun, Helene occupies a significant place in the Solar System's architecture. As a moon, Helene demonstrates the incredible diversity of natural satellites that orbit larger celestial bodies throughout our Solar System.

The Helene physical characteristics reveal a world of remarkable dimensions and properties. The Helene radius measures 17.6 km, making it 362.0× smaller than Earth's size.

The Helene orbit reveals fascinating details about its journey around the Sun and its relationship to other Solar System objects. The Helene orbit has a semimajor axis of 377,396 km (0.003 AU), placing it 396.4× smaller than Earth's distance from the Sun. The Helene orbit is nearly circular with an eccentricity of 0.002 (7.6× smaller than Earth's orbital eccentricity), resulting in relatively stable solar heating throughout its year. The Helene orbit takes 0.00 hours to complete (11534411.4× smaller than Earth's orbital period), defining the length of its year. The orbital inclination of 0.199° indicates how much the Helene orbit is tilted relative to the Solar System's ecliptic plane. This low inclination means Helene follows a path very close to the plane where most planets orbit, suggesting a stable formation history.

The Helene rotation and axial orientation provide crucial insights into its daily and seasonal cycles, as well as its orbital dynamics. The Helene axial tilt of 0° determines the intensity and nature of seasonal variations. With minimal axial tilt, Helene experiences virtually no seasonal changes, maintaining relatively constant temperatures throughout its year. The orbital orientation parameters reveal additional details about Helene'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 Helene temperature and atmospheric conditions are fundamental to understanding its habitability and environmental characteristics. The Helene average temperature of 0.0 K (-273.1 °C) (-459.7°F) provides the baseline for understanding its climate. These extremely cold temperatures make Helene 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), Helene presents a dramatically different thermal environment. Being closer to the Sun than Earth, Helene receives more intense solar radiation, contributing to its temperature profile.

The Helene escape velocity and shape characteristics reveal important details about its gravitational field and rotational dynamics. The Helene 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 Helene to retain a substantial atmosphere. The Helene 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.