Cassini Spacecraft’s 20-Year Voyage

The Cassini-Huygens spacecraft, commonly called Cassini, is an unmanned interplanetary probe jointly developed by NASA, the European Space Agency (ESA) and the Italian Space Agency (ASI). Launched in 1997, it reached the Saturn system in 2004 and studied the ringed planet and its moons until 2017 when it was deliberately crashed into Saturn.

Key Facts

• Joint NASA/ESA/ASI robotic spacecraft sent to study Saturn and its system
• Launched in 1997; entered Saturn orbit in 2004 for a close-up study
• Mission ended in 2017 with planned impact into Saturn after 20 years
• Delivered Huygens probe successfully to Titan moon in 2005
• Collected extensive data and images, reshaping understanding of Saturn.

• Cassini’s orbit insertion maneuver around Saturn was 96 minutes long – the most complicated robotic spacecraft maneuver ever attempted
• The Huygens probe landed on Saturn’s moon Titan in 2005, making it the most distant landing from Earth a spacecraft has ever achieved
• Cassini completed 294 orbits around Saturn over 20 years, collecting 635 GB of scientific data and images
• The spacecraft came within 1600 miles of Enceladus’ surface in 2015, close enough to sample particles from its subsurface ocean plumes
• Cassini examined Saturn’s atmosphere using instruments capable of perceiving particles ten times smaller than the diameter of a human hair
• The mission exposed new moons orbiting Saturn, like tiny, half-mile-wide Daphnis found within the planet’s rings

Mission Objectives

The key objectives behind the Cassini-Huygens mission to Saturn were:

• Study Saturn’s rings in detail – composition, dynamics, origin
• Study Saturn’s magnetosphere and its interaction with solar wind
• Observe Saturn’s moons – surfaces, compositions, atmospheres
• Study Titan’s dense atmosphere and conditions for life
• Map surface features and topography of Titan and Saturn’s icy moons
• Analyze Saturn’s atmosphere and weather phenomena

Vital Statistics

Cassini Orbiter Vital Statistics

Instruments and Experiments

Cassini carried a complement of 12 scientific instruments and conducted numerous experiments during its 20-year mission, including:

• Imaging cameras: Took ~450,000 images of Saturn, rings, and moons
• Magnetometers : Mapped Saturn’s magnetosphere
• Mass spectrometers: Analyzed atmospheric composition
• Radar mapper: Detected subsurface features on Titan
• Radio science subsystem: Studied gravity fields and atmospheres
• Cosmic dust analyzer: Studied ice grains and comet dust
• Ion/neutral mass spectrometer: Analyzed Titan’s atmosphere

Key Discoveries

Some groundbreaking discoveries and first-ever observations by Cassini include:

• First spacecraft to orbit Saturn for an extended period
• Evidence of subsurface ocean on Enceladus with conditions to support life
• Liquid methane/ethane lakes and seas on Titan’s surface
• Hurricane-like storms at both Saturn’s poles
• Study of ripples and changes in Saturn’s rings
• New information on evolution and origin of Saturn’s moons
• Observation of seven new moons and improved understanding of known ones

Huygens Probe & Findings on Titan

• Delivered ESA’s Huygens probe to Saturn’s largest moon Titan in 2005, first landing on a moon in the outer solar system
• Huygens analyzed the dense atmosphere during 2-hour descent to Titan’s surface
• Found evidence of flowing liquid, eroded solid formations indicating rain and river channels
• Confirmed methane clouds, wind patterns and dynamic climate
• Studied rocks and ice blocks on Titan’s frozen surface

End of Mission

After 20 prolific years revealing Saturn’s secrets, Cassini’s mission ended with a planned ‘Grand Finale’:

• Cassini entered final phase orbiting between Saturn and the innermost ring
• Collected close observations before deliberately plunging into Saturn in 2017
• Ensured destruction to prevent possible impact with and contamination of moons that may harbor life

The revelations and data from the mission will fuel new insights into Saturn, its rings, magnetosphere, moons like Titan and icy worlds for decades. With astounding images and evidence of potentially inhabitable environments, Cassini has shaped our understanding of the Saturn system and Enceladus and Titan as prime targets for future exploration.