Rosetta Mission

ESA’s comet-chasing mission around 67P/Churyumov–Gerasimenko.

Overview

Rosetta was a landmark ESA mission designed to rendezvous with, orbit, and study Comet 67P/Churyumov–Gerasimenko. After a decade-long journey, it became the first spacecraft to orbit a comet and escort it as it moved around the Sun.

Its onboard instruments and deployed lander, Philae, helped reveal how comets are structured and what they are made of — offering clues to the early Solar System and the origins of water and organics on Earth.

📌 Mission Facts

Agency: ESA (with NASA instruments)

Launch: 2 March 2004

Comet Arrival: August 2014

Lander: Philae

Status: Completed (2016)

Target: Comet 67P/Churyumov–Gerasimenko

Mission Objectives

  • Escort a comet along its orbit and monitor activity in detail.
  • Map the comet nucleus in 3D and study its geology.
  • Measure gases, dust, plasma, and organic compounds in the coma.
  • Deploy Philae to perform on-surface experiments.
  • Improve our understanding of the role of comets in delivering volatiles to Earth.

Why Rosetta Matters

Rosetta showed that comets are complex, geologically active worlds rather than simple dirty snowballs. Its discoveries challenged assumptions about where Earth’s water comes from and confirmed that organic molecules exist in primitive bodies from the Solar System’s infancy.

Key Discoveries

  • Identified a rich variety of organic molecules in the comet’s atmosphere.
  • Found that the comet’s water has a different deuterium ratio than Earth’s oceans.
  • Revealed a double-lobed “rubber duck” shape with cliffs, pits, and smooth plains.
  • Observed jets and seasonal changes as the comet approached the Sun.

Mission Timeline

  • 🚀 2004 — Launch aboard Ariane 5.
  • 🌀 2004–2009 — Multiple Earth and Mars gravity assists; asteroid fly-bys.
  • 💤 2011 — Spacecraft placed into deep-space hibernation.
  • ⏰ 2014 — Wake-up and rendezvous with Comet 67P.
  • 🪂 Nov 2014 — Philae released and landed on the surface.
  • 🌙 2016 — Controlled descent onto the comet and end of mission.

Watch

🔗 ESA — Rosetta mission overview video.
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