News on the Huygens probe's landing on Titan

[Whitters]

N° 63-2004 – Paris, 7 December 2004

Second space Christmas for ESA: Huygens to begin its final journey to Titan/ Media activities.

One year after Mars Express’ arrival at Mars, the mighty rules of celestial mechanics have again set Christmas as the date for a major ESA event in deep space.

At 1.25 billion km from Earth, after a 7-year journey through the Solar system, ESA’s Huygens probe is about to separate from the Cassini orbiter to enter a ballistic trajectory toward Titan, the largest and most mysterious moon of Saturn, in order to dive into its atmosphere on 14 January. This will be the first man-made object to explore in-situ this unique environment, whose chemistry is assumed to be very similar to that of the early Earth just before life began, 3.8 billion years ago.

The Cassini-Huygens pair, a joint mission conducted by NASA, ESA and the Italian space agency (ASI), was launched into space on 15 October 1997. With the help of several gravity assist manoeuvres during flybys of Venus, Earth and Jupiter, it took almost 7 years for the spacecraft to reach Saturn. The Cassini orbiter, carrying Huygens on its flank, entered an orbit around Saturn on 1 July 2004, and began to investigate the ringed planet and its moons for a mission that will last at least four years. The first distant flyby of Titan took place on 2-3 July 2004. It provided data on Titan's atmosphere which were confirmed by the data obtained during the first close flyby on 26 October 2004 at an altitude of 1174 km. These data were used to validate the entry conditions of the Huygens probe. A second close flyby of Titan by Cassini-Huygens at an altitude of 1200 km is scheduled on 13 December and will provide additional data to further validate the entry conditions of the Huygens probe.

On 17 December the orbiter will be placed on a controlled collision course with Titan in order to release Huygens on the proper trajectory, and on 21 December (some dates and times are subject to minor adjustment for operational reasons, except the entry time on 14 January which is know to within an accuracy of under 2 minutes) all systems will be set up for separation and the Huygens timers will be set to wake the probe a few hours before its arrival at Titan.

The Huygens probe is due to separate on the morning of 25 December at about 05:08 CET. Since the Cassini orbiter will have to achieve precise pointing for the release, there will be no real-time telemetry available until it turns back its main antenna toward Earth and beams the recorded data of the release. It will take over an hour (67 min) for the signals to reach us on Earth. The final data confirming the separation will be available later on Christmas Day.

After release, Huygens will move away from Cassini at a speed of about 35 cm per second and, to keep on track, will spin on its axis, making about 7 revolutions a minute. Huygens will not communicate with Cassini for the whole period until after deployment of the main parachute following entry into Titan’s atmosphere. On 28 December Cassini will then manoeuvre off collision course to resume its mission and prepare itself to receive Huygens data, which it will record for later playback to Earth.

Huygens will remain dormant until a few hours before its arrival at Titan on 14 January. The entry into the atmosphere is set for 11:15 CET. Huygens is planned to complete its descent in about two hours and 15 minutes, beaming back its science data to the Cassini orbiter for replay to Earth later in the afternoon. If Huygens, which is designed as an atmospheric probe rather than a lander, survives touchdown on the surface, it could deliver up to 2 hours of bonus data before the link with Cassini is lost.

Direct radio signals from Huygens will reach Earth after 67 minutes of interplanetary travel at the speed of light. An experiment has been set up by radio scientists that will use an array of radio telescopes around the Pacific to attempt to detect a faint tone from Huygens. If successful, early detection is not expected before around 11:30 CET.

The European Space Agency owns and manages the Huygens probe and is in charge of operations of the probe from its control centre in Darmstadt, Germany.  NASA's Jet Propulsion Laboratory in Pasadena, California, designed, developed and assembled the Cassini orbiter.  NASA's Deep Space Network, also managed by JPL, will be providing communications support via the Cassini orbiter and relaying it to ESA’s control centre in Darmstadt for processing.  The Italian Space Agency provided the high-gain antenna on the Cassini orbiter, much of the radio system and elements of several of Cassini's science instruments. The Huygens payload has been provided by teams including from CNES, DLR, ASI and PPARC, and outside Europe, from NASA.

Practical arrangements for the Media wishing to cover the event

These dramatic events marking the first attempt ever to unveil the mysteries of Titan in-situ, a distant world bigger than Mercury and Pluto which may hold clues to the early days of our own planet, will be marked by several media activities not to be missed. Pencil them into your diary.

Saturday 25 December
Spacecraft operations will be run at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.


05:08 CET   Expected separation of the Huygens probe from the Cassini orbiter
~07:00 CET    Status report upon successful separation from NASA/JPL

10:00 CET
at the latest : ESA press release assessing the separation of the Huygens probe  

~10:00 CET    ESA TV Video News Release produced at JPL during separation


Transmission details will be on http://television.esa.int

12:00 CET   Replay of ESA TV Video News Release on separation


Thursday 13 January
ESA’s ESOC establishment in Darmstadt, Germany, will act as the main European press centre. The Huygens Principal Investigators, the ESA Huygens Mission Manager and Project Scientist will be at ESA/ESOC and available for interviews.  
   




Satellite details for ESA TV broadcast reception:

The ESA TV Service provides live broadcasts of ESA’s most important events on the Astra 2-C satellite, using a digital transponder that enables everyone in the satellite’s footprint, with a digital receiver and a parabolic pointing at 19.2 degrees East, to follow these events.

For more information and updates, please check the ESA TV Website: http://television.esa.int .

And on the Web

You can follow all main Cassini/Huygens mission events on the ESA web at: http://saturn.esa.int Here you will find information on Cassini-Huygens and its status, a rich selection of multimedia material, news on the separation of Huygens from the Cassini orbiter and the latest updates on January 13. There will be continuous coverage during the last exciting hours of the descent on 14 January, with the first image expected late on 14 January or on 15 January.
Bookmark now http://saturn.esa.int ! And if you have not already done so, subscribe to the ESA portal news  at http://www.esa.int/esaCP/subscribers.html , you will get the latest news on this fascinating mission directly into your mail box!

Messages from earthlings and pop music heading to Titan Before the mission was launched, ESA offered Europeans a unique opportunity to send a message to the unknown. Over 80 000 people wanted to share the excitement of this mission and wrote or drew a message that was engraved on a CD-ROM put on board the Huygens probe. The messages can be seen on http://television.esa.int/Huygens/index.cfm

The same CD ROM carries four pop songs, composed by French musicians Julien Civange and Louis Haéri. More about this project at http://www.music2titan.com




[ This Message was edited by: Whitters on 2004-12-15 23:41 ]

[Whitters]

What does Titan hide under its thick orange haze? After a seven-year journey aboard the Cassini orbiter, the Huygens probe will make a daring dive down through the atmosphere of Saturn's mysterious moon Titan. Will it land with a splash or a thud? Find out more in VideoTalk.

Read more:
http://www.esa.int/SPECIALS/Cassini-Huygens/index.html

[Rick]

The Huygens probe appears to be on the right course after being unleashed on its journey to Saturn's largest moon Titan, says the US space agency (Nasa).

The Cassini orbiter snapped images of the 2.7m-wide robotic lab as it moved away from its mothership.

Information from the images is helping engineers understand its trajectory, and so far, say Nasa officials, it appears to be right on the mark.

Full story.

[Whitters]

NASA Science News for December 30, 2004

Soon, the European Space Agency's Huygens probe will parachute to the surface of Saturn's huge moon Titan.  Huygens will sample Titan's air, examine the moon's surface, and listen for alien sounds.  It could be the strangest adventure in the history of space exploration.

FULL STORY at

http://science.nasa.gov/headlines/y2004/30dec_titan.htm?list907772

[Whitters]

ESA PR 67-2004. The European Space Agency’s Huygens probe was successfully released by NASA’s Cassini orbiter early this morning and is now on a controlled collision course toward Saturn’s largest and most mysterious moon, Titan, where on 14 January it will make a descent through one of the most intriguing atmospheres in the solar system to an unknown surface.

The separation occurred at 02:00 UTC (03:00 CET): A few minutes after separation, Cassini turned back to Earth and relayed back information about the separation. This signal then took 1 hour and 8 minutes to cross the 1.2 billion kilometres separating the Cassini spacecraft and Earth.

Full story: http://www.esa.int/SPECIALS/Cassini-Huygens/SEMVR53AR2E_0.html

[Rick]

From: Natalia Clarke <natalia.clarke@screenhouse.co.uk>

Happy New Year!

I would like to draw your attention to the next programme in the Stardate series - "Mission to Titan". This will be broadcast LIVE on BBC2 at 23.30 on Friday 14th January and will feature the latest images from the Huygens probe, which will have landed on Saturn's moon, Titan, earlier that day.

As part of the show, we will have a live Question & Answer session with 3 scientists who have been closely involved in the mission:

Prof John Zarnecki - the Principle Investigator who has dedicated 17 years of his life to work on the instrument that will try to figure out the characteristics of Titan's surface

Prof Marty Tomasko - The Principle Investigator on the Huygens imaging team. He's hoping to create fantastic panoramas of Titan's surface, which has never before been seen, because of the thick orange haze blanketing the satellite.

Dr. Athena Coustenis - A Titan expert, who also works on the Huygens atmospheric structure instrument.

To put a question forward, go to http://www.open2.net and click on "Ask an Astronomer" at the bottom of the page.

Please feel free to forward this to any other members of your astronomy society who may be interested.

We hope you enjoy the show!

Kind regards,

Natalia
________________________________
Natalia Clarke
Screenhouse Productions Limited
Chapel Allerton House
114 Harrogate Road
Leeds LS7 4NY

[Whitters]

N° 04-2005 &#8211; Paris, 18 January 2005

More of Titan&#8217;s secrets to be unveiled on January 21

One week after the successful completion of Huygens&#8217; mission to the atmosphere and surface of Titan, the largest and most mysterious moon of Saturn, the European Space Agency is bringing together some of the probe&#8217;s scientists to present and discuss the first results obtained from the data collected by the instruments.

After a 4 billion kilometre journey through the Solar System that lasted almost 7 years, the Huygens probe plunged into the hazy atmosphere of Titan at 11h13 CET on January 14 and landed safely on its frozen ground at 13h45 CET. It continued transmitting from the surface for several hours, even after the Cassini orbiter dropped below the horizon and stopped recording the data to relay them towards Earth. Cassini received excellent data from the surface of Titan for 1 hour 12 minutes.

More than 474 megabits of data were received in 3 hours 44 minutes from Huygens, including some 350 pictures collected during the descent and on the ground, which revealed a landscape apparently modelled by erosion with drain channels, shoreline-like features and even pebble-shaped objects on the surface.

The atmosphere was probed and sampled for analysis at altitudes from 160 km to the ground, revealing a uniform mix of methane with nitrogen in the stratosphere. Methane concentration

increased steadily in the troposphere down to the surface. Clouds of methane at about 20 km altitude and methane or ethane fog near the surface were detected.

The probe&#8217;s signal, monitored by a global network of radio telescopes on Earth, will help reconstruct its actual trajectory with an accuracy of 1 km and will provide data on Titan&#8217;s winds. Early analysis of the received signal indicate that Huygens was still transmitting after 3 hours on the surface. Later recordings are being analysed to see how long Huygens kept transmitting from the surface.

Samples of aerosols were also collected at altitudes between 125 and 20 km and analysed onboard. During the descent, sounds were recorded in order to detect possible distant thunder from lightning, providing an exciting acoustic backdrop to Huygens&#8217;s descent.

As the probe touched down at about 4.5 m/s, a whole series of instruments provided a large amount of data on the texture of the surface, which resembles wet sand or clay with a thin solid crust, and its composition, mainly a mix of dirty water ice and hydrocarbon ice, resulting in a darker soil than expected. The temperature measured at ground level was about -180 degrees Celsius.

Some stunning preliminary results were presented shortly after the science teams obtained access to their data, on 15 January. After several days of processing and analysis of these results, the scientists will be able to deliver a better view of this strange distant world during a press conference on Friday 21 January at 11h00 CET at ESA&#8217;s Headquarters in Paris (rebroadcast at several other ESA establishments). See the attached form.

Participating in this event:

David Southwood
ESA&#8217;s Director of Science Programmes,

Jean-Pierre Lebreton
ESA&#8217;s Huygens Project Scientist and Mission Manager,

Marcello Fulchignoni (TBC)
Principal Investigator for the Huygens Atmospheric Structure Instrument (HASI), from the University of Paris/Observatoire de Paris-Meudon, France,

Martin G. Tomasko
Principal Investigator for the Descent Imager and Spectral Radiometer (DISR), from the University of Arizona in Tucson, United States,

John C. Zarnecki
Principal Investigator for the Surface Science Package (SSP), from the Open University at Milton Keynes, United Kingdom,

Guy Israel
Principal Investigator for Aerosol Collector and Pyroliser (ACP), from CNRS, Service d&#8217;Aéronomie, Verrières-le-Buisson, France

Toby Owen
Cassini Interdisciplinary Scientist for the atmospheres of Titan and Saturn, from the Institute for Astronomy, Honolulu, United States.

The ESA TV service will televise the press conference live via satellite (Eutelsat W1). For transmission details, check http://television.esa.int

NASA-TV will broadcast the press conference across the US and as partner in the Cassini-Huygens mission ensure live streaming. For details, see:

http://www.nasa.gov/multimedia/nasatv/

The Cassini-Huygens mission is a cooperation between NASA, ESA and ASI, the Italian space agency. The Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, is managing the mission for NASA&#8217;s Office of Space Science, Washington DC. JPL designed, developed and assembled the Cassini orbiter.

[Whitters]

2005 March 30
Special General Meeting

The Geological Society, Burlington House, Piccadilly, London 17:30 - 20:00 (Doors open at 17:00) Tea available. Admission free and open to all Programme

"Titan revealed - first results from Huygens"   Dr. Simon F. Green,
Space Science Research Group, Planetary and Space Sciences Research Institute, The Open University, "Sky notes" - Martin Mobberley "BAA Instrument Number One" -Bob Marriott, Director, I&I Section and Curator of Instruments

Nick Hewitt
Meetings Secretary

[Whitters]

ESA's Huygens probe successfully descended through the atmosphere of Titan, Saturn's largest moon, and safely landed on its surface on 14 January 2005. An extraordinary new world has been unveiled. The unique data obtained by the six Huygens experiments are now being archived in the ESA Planetary Science Archive (PSA). A copy of the archived data set is also available in the NASA Planetary Data System (PDS).

More: http://www.esa.int/SPECIALS/Cassini-Huygens/SEM8TYIZBQE_0.html

[Rick]

Huygens: 'Ground Truth' From an Alien Moon

After a two-and-a-half-hour descent, the metallic, saucer-shaped spacecraft came to rest with a thud on a dark floodplain covered in cobbles of water ice, in temperatures hundreds of degrees below freezing. The alien probe worked frantically to collect and transmit images and data about its environs -- in mere minutes its mothership would drop below the local horizon, cutting off its link to the home world and silencing its voice forever.

Although it may seem the stuff of science fiction, this scene played out 12 years ago on the surface of Saturn's largest moon, Titan. The "aliens" who built the probe were us. This was the triumphant landing of ESA's Huygens probe.

Huygens, a project of the European Space Agency, traveled to Titan as the companion to NASA's Cassini spacecraft, and then separated from its mothership on Dec. 24, 2004, for a 20-day coast toward its destiny at Titan.

The probe sampled Titan's dense, hazy atmosphere as it slowly rotated beneath its parachutes, analyzing the complex organic chemistry and measuring winds. It also took hundreds of images during the descent, revealing bright, rugged highlands that were crosscut by dark drainage channels and steep ravines. The area where the probe touched down was a dark, granular surface, which resembled a dry lakebed.

More: http://www.jpl.nasa.gov/news/news.php?feature=6718