Processing Altimetric Data (PAD) (2005/2006)

Cassini - Huygens is the first mission planned to explore Saturn system of moons and rings from a spacecraft in its orbit. It is an international collaboration between three space agencies with the contribute of seventeen nations.
The NASA Jet Propulsion Laboratory has realized and managed Cassini orbiter, the European Space Agency the Huygens probe and the Italian Space Agency has provided the high gain antenna onboard the space platform.
Cassini has entered Saturn orbit on June 30, 2004 after a seven years' journey started on October 15, 1997. The Huygens probe separated from the orbiter on December 25, 2004 and, on January 14, 2005, after a twenty days' descend landed on Saturn's biggest moon, Titan, perpetually wrapped up in a thick and hazy atmosphere, reaching the farthest place a man-made spacecraft has successfully landed away from Earth.

Cassini task is to study Saturn and its moon Titan, while that of the probe has been to gather as more information as possible during its descent to Titan in order to analyze and photograph its clouds, atmosphere and surface and then to send the collected data to the Earth through Cassini communication system.
Both are equipped with a great deal of sophisticated instruments, 12 on Cassini and 6 on Huygens probe. They are optical and microwaves instruments able to work from a great distance: cameras, spectrometers, radar and radio.
One of the instruments onboard Cassini is a radar able to operate in three ways: imaging, altimetry, and radiometry, where each mode allows collecting different types of data.
Cassini completed its initial four-year mission to explore the Saturn System in June 2008 and the first extended mission, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is seeking to make exciting new discoveries in a second extended mission called the Cassini Solstice Mission until September 2017.

This project aim has been the processing of Cassini radar data in altimeter mode.

The scientific objective of CASSINI RADAR is the study of Titan, the largest of Saturn's 34 moons. Bigger then the planets Mercury and Pluto, Titan is of great interest for scientists as it is the only moon in our solar system with its own atmosphere and like Earth's before life developed.
Titan's thick and hazy atmosphere has prevented the knowledge of its surface as no kind of telescope has been able to show something more then undefined shapes.
Now thanks to the radar which is able to penetrate the clouds, it is possible to get accurate information on its geological structure. From the research on its habitat scientists expect to know something more on planets formation and, in particular, on Earth's origins.

CASSINI RADAR Scientific Objectives:

  • to determine whether oceans exist on Titan, and, if so, to determine their distribution;
  • to investigate the geologic features and topography of the solid surface of Titan;
  • to acquire data on non-Titan targets (rings, icy satellites) as conditions permit.

CASSINI RADAR can operate as:

  • Synthetic Aperture Radar Imager [SAR] (13.78 GHz Ku-band; 0.35 to 1.7 km resolution)
  • Altimeter (13.78 GHz Ku-band; 24 to 27 km horizontal, 90 to 150 m vertical resolution)
  • Radiometer (13.78 GHz passive Ku-band; 7 to 310 km resolution)

The project has started in July 2005 and ended in 2006.

CO.RI.S.T.A. papers on the project:

  • G. Alberti, L. Festa, C. Papa, G. Vingione (CO.RI.S.T.A.), C. Catallo, F. Spataro (Alcatel Alenia Space Italia), E. Flamini (Agenzia Spaziale Italiana), R. Orosei (Istituto Nazionale di Astrofisica), G. Picardi, R. Seu (Università di Roma "La Sapienza"), "The Processing of Altimetric Data (PAD) System for Cassini RADAR", VII National Congress of Planetary Sciences, 5-9 September 2006, San Felice al Circeo (LT), Italy.       
  • G. Vingione, G. Alberti, C. Papa, L. Festa (CO.RI.S.T.A), G. Picardi, R. Seu, P.P. Del Marmo (INFO-COM, University of Rome La Sapienza), R. Orosei (IASF Istituto di Astrofisica Spaziale e Fisica Cosmica, CNR), P. Callahan, S. Wall (Jet Propulsion Laboratories, California Institute of Technology), "Processing of Altimetric Data of CASSINI mission", European Geosciences Union General Assembly 2007 Vienna, Austria, 15 20 April 2007.       
  • Alberti, G.; Festa, L.; Papa, C.; Vingione, G. "A Waveform Model for Near-Nadir Radar Altimetry Applied to the Cassini Mission to Titan", Geoscience and Remote Sensing, IEEE Transactions on, Issue Date: July 2009.       

  • Degree thesis developed on this subject:

  • Degree thesis "Performances analysis and preliminary project of Cassini radar processing in altimeter mode" developed by Guido Vingione, academic year 2003-2004, Second University of Naples , Faculty of Engineering, Aerospace Department.      

  • Degree thesis "Processing of CASSINI SAR data" developed by Cesare Tasquier, academic year 2005-2006, Second University of Naples, Faculty of Engineering, Department of Aerospace and Mechanical Engineering.      

  • PhD thesis by Guido Vingione, "Radar Altimeter General Waveform Model and its Application to Cassini Mission", Second University of Naples, Department of Aerospace and Mechanical Engineering, November 2007.      

  • For further information please contact:

    Gianni Alberti
    phone: +39-081-5935101

    Artist's View of Cassini approaching Saturn
    Photo: NASA

    October 2004: Saturn, image taken by Cassini
    Credit: NASA/JPL Space Science Institute

    Saturn image
    Photo: NASA