Pallas

Definition

Pallas is the second-largest asteroid in the main asteroid belt, after Ceres. It is a large, irregularly shaped rocky body that orbits the Sun between the orbits of Mars and Jupiter, and is considered one of the most massive and largest of the main-belt asteroids.

5 Must Know Facts For Your Next Test

1. Pallas was discovered in 1802 by the German astronomer Heinrich Wilhelm Matthias Olbers, making it one of the first three asteroids discovered.
2. Pallas has an estimated diameter of about 512 kilometers, making it the third-largest asteroid after Ceres and Vesta.
3. Pallas has a high inclination of about 34.8 degrees to the ecliptic, which is one of the highest inclinations of any asteroid in the main belt.
4. Pallas is believed to be composed of a mixture of silicate rocks and metals, similar to the composition of the Earth's crust and mantle.
5. The surface of Pallas is thought to be heavily cratered, indicating a long and complex collisional history.

Review Questions

• Describe the physical characteristics of the asteroid Pallas, including its size, shape, and composition.
  • Pallas is the second-largest asteroid in the main asteroid belt, with an estimated diameter of about 512 kilometers. It has an irregular, non-spherical shape, which is typical of many asteroids. Pallas is believed to be composed of a mixture of silicate rocks and metals, similar to the composition of the Earth's crust and mantle. The surface of Pallas is heavily cratered, indicating a long and complex collisional history.
• Explain the significance of Pallas's high inclination to the ecliptic and how it compares to other main-belt asteroids.
  • Pallas has a high inclination of about 34.8 degrees to the ecliptic, which is one of the highest inclinations of any asteroid in the main belt. This means that Pallas's orbit is significantly tilted compared to the plane of the Solar System, the ecliptic. This high inclination is an important characteristic that sets Pallas apart from many other main-belt asteroids, which typically have lower inclinations. The high inclination of Pallas provides insights into the formation and evolution of the Solar System, as well as the complex dynamics of the main asteroid belt.
• Discuss the historical significance of the discovery of Pallas and its role in the early understanding of the main asteroid belt.
  • Pallas was discovered in 1802 by the German astronomer Heinrich Wilhelm Matthias Olbers, making it one of the first three asteroids discovered, along with Ceres and Vesta. The discovery of Pallas, and the subsequent discoveries of other main-belt asteroids, played a crucial role in the early understanding of the structure and composition of the Solar System. The existence of a large number of small bodies orbiting the Sun between Mars and Jupiter challenged the prevailing view of the Solar System and led to the recognition of the main asteroid belt as a distinct region of the Solar System, with important implications for our understanding of planetary formation and evolution.

Related terms

Main Asteroid Belt: The main asteroid belt is the circumstellar disc in the Solar System located between the orbits of Mars and Jupiter, where a large majority of the asteroids in the Solar System are found.

Ceres: Ceres is the largest and most massive object in the main asteroid belt, with a diameter of about 950 kilometers, making it a dwarf planet.

Irregular Shape: Irregular shape refers to the non-spherical, often asymmetrical shape of asteroids, which is a result of their formation and collisional history.