In focus: Ultima Thule

In focus: Ultima Thule

Introduction

• Ultima Thule is a small rocky and icy trans-Neptunian planetesimal in the Kuiper belt about 30 km in radius.
  • Planetesimal is one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system
• Ultima Thule belongs to a class of Kuiper belt objects called the “cold classicals”.
• Ultima Thule is a contact binary made up of 2 differently shaped lobes.
• One is a large, strangely flat lobe nicknamed “Ultima“
• The other is a smaller, somewhat rounder lobe named “Thule“.

 

Composition

• Data from New Horizons suggests evidence of methanol, water ice, and organic molecules on Ultima Thule.

 

Surface features

Pictures of Ultima Thule highlight

• Bright spots and patches
• Hills and troughs
• Craters and pits
• An impact crater, 8-kilometer-wide, nicknamed Maryland crater.

 

Significance

• Since it is an ancient relic, the discoveries will help in better understanding of solar system formation.

 

 

In brief: Kuiper Belt Objects and New Horizons Mission

• Kuiper belt extends from about 30 to 50 AU (Astronomical Unit, 1 AU= distance between Sun and Earth) from the Sun.
• When the solar system was young, a large number of icy planetesimals formed in the region beyond Jupiter.
• The gravitational forces of the massive Jovian planets pushed most of these planetesimals beyond Neptune’s orbit, concentrating them into a belt centered on the plane of the ecliptic called as Kuiper Belt.
• The objects in the Kuiper Belt are called trans-Neptunian objects or Kuiper Belt Objects.
• The objects within the Kuiper Belt form the most primitive objects from the beginning of the formation of the solar system.
• Besides, most of the comets also have their origin in Kuiper belt.
• Thus, Kuiper Belt is a laboratory for studying well-preserved primitive material from the planet formation era 4.5 billion years ago.

 

 

New Horizon 

• New Horizons is NASA’s space mission to Pluto and Kuiper Belt Objects.
• New Horizons has revolutionized our understanding of most remote members of the solar system.
• Launched in 2006, it went past Pluto and Charon in 2015.
• It is also the first mission to explore the solar system’s “third zone,” the region beyond the giant planets called the Kuiper Belt.