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UYGENS' INSTRUMENTS

infrared Titan
HUYGENS' INSTRUMENTS
  • 1. HASI - Huygens Atmosphere Structure Instrument, measures physical and electrical properties of Titan's atmosphere. An on-board microphone will send back sounds from Titan.
    2. GCMS - Gas Chromatograph and Mass Spectrometer, identifies and measures chemical species abundant in moon's 'air'. It is equipped with gas samplers which will be filled at high altitude for analysis later in the descent.
    3. ACP - Aerosol Collector and Pyrolyser, draws in and analyses atmospheric aerosol particles. Each sampling device can collect about 30 micrograms of material.
    4. DISR - Descent Imager/Spectral Radiometer, images descent and investigates light levels
    5. DWE - Doppler Wind Experiment, studies direction and strength of Titan's winds
  • 6. SSP - Surface Science Package, determines physical properties of moon's surface. The package includes an accelerometer to measure the impact deceleration, and other sensors to measure the index of refraction,thermal conductivity, heat capacity, temperature, speed of sound, and dielectric constant of the material at the landing site.

One week after the successful completion of Huygens' mission to the atmosphere and surface of Titan, the European Space Agency is bringing together some of the probe's scientists to present and discuss the first results obtained from the data collected by the instruments.

New results were outlined at a press conference in Paris, France on Friday, 21 st Jan.

Liquid methane rain feeds river channels, lakes, streams, and springs on the surface of Saturn's moon Titan.
PAGE TWO-New Results arrowleft.gif

First Data from accelerometer
First Data from Penetrometer as it extended 15 cm into the surface.
Initial results show that Titan has a troposphere, At a height of 50 km up The probe measured a freezing 203C as it passed through it, compared with a -179C ground temperature.
One radio channel was lost so only 350 photos were taken, instead of the expected 700+.
The probe landed at a slight 20 degree tilt (Revised: 8 tilt) on to a `rock (of ice)` strewn surface that has a brittle surface crust, below which is a thicker layer with the consistency of wet sand or clay. Its composition,is mainly a mix of dirty water ice and hydrocarbon ice, resulting in a darker
soil than expected.
The atmospheric pressure is similar to earth

The probes descent was bumpier than expected in the upper atmosphere. During its descent through high-altitude haze, it rocked about 10 - 20 degrees. But below the haze layer, the probe was more stable, tilting less than 3 degrees. The reason for this seems to be that the wind changed direction at about 25 kilometres altitude.
The winds on Titan are found to be flowing in the direction of Titan's rotation (from west to east) at nearly all altitudes. The maximum speed of roughly 120 metres per second (430 km/h) was measured about ten minutes after the start of the descent, at an altitude of about 120 km. The winds are weak near the surface and increase slowly with altitude up to about 60 km. This pattern does not continue at altitudes above 60 km, where large variations in the Doppler measurements are observed. Scientists believe that these variations may arise from significant vertical wind shear. That Huygens had a rough ride in this region was already known from the science and engineering data recorded on board Huygens.

No data from any of the nine sensors was lost. More than 474 megabits of data were received.
When Huygens touched down it experienced deceleration of about 15g in 40 milliseconds.

"It is clear that the surface was soft. The best image I can give is of a crme brle, with a crust on the surface and softer material underneath. We also know that on impact, a little methane evaporated in contact with a hot tube of one of the instruments."- Jean-Pierre Lebreton, the director of the Huygens mission at ESA.

Data from the Gas Chromatograph and Mass Spectrometer (GCMS) indicate methane is evaporating from the surface (probably due to Huygens impacting at 4.5 meters per second).The data also shows that the probe passed through a dense methane cloud or haze at a height of 18 - 20 kilometres. These matches well with DISR's observations: at 25 km up the surface was still fuzzy, but below 18 km the clarity was near-perfect.

When the mission was designed, it was decided that the DISR's 20-Watt landing lamp should turn on 700 metres above the surface and illuminate the landing site for as long as 15 minutes after touchdown.

"In fact, not only did the landing lamp turn on at exactly 700 metres, but also it was still shining more than an hour later"

The non detection of the non-radiogenic form of argon, by Cassini spacecrafts Ion Neutral Mass Spectrometer and Huygen probes Gas Chromatograph Mass Spectrometer (GCMS), in Titans atmosphere suggests that the building blocks, or "planetesimals," that formed Titan contained nitrogen mostly in the form of ammonia.
"I think what's clear from the data is that Titan has accreted or acquired significant amounts of ammonia, as well as water."
"The features seen in the radar data suggests ammonia is at work on Titan in cryovolcanism."

UPDATE: The communications failure occurred on Cassini, not Huygens, and was caused by an error "as simple as throwing a switch to, On. The science projects team at ESA did not switch on Cassini`s software; Doh!.

"In Space no one hears you scream"

The probe was to transmit data on two channels, A and B. A Doppler wind experiment was to use Channel A, a very stable frequency.

But the order to activate the receiver, or oscillator, for Channel A a signal was never sent, so the entire mission operated through Channel B, which is less stable. However, there is hope that some of the data survived. The doppler wind data from Huygens will need to be pieced together from the many ground telescopes that were tuning into the probes descent, due to the communications glitch.

"We do have Channel B data and although driven by a very poor and unstable oscillator, we may be able to get a little bit of data.

Some of the Channel A signal reached Earth and was picked up by radio telescopes. "We now have some of this data and lots of work to do to try to catch up."

The National Radio Astronomy Observatory's Very Long Baseline Array radio telescope, which is operated from Socorro, New Mexico, used eight of its 10 dishes to listen to the 10-watt transmissions from Huygens during the probe's descent.

The VLBA collected about 7 1/2 hours of data on magnetic discs beginning at about 2 a.m. Friday from the probe.

The craft had sent back three hours, 37 minutes and 26 seconds of data. Seventy minutes of this was transmitted from the surface.

Click to enlarge!Raw Data

triplet.0a0.jpg triplet.2a0.jpg triplet.3a0.jpg triplet.6a0.jpg triplet.7a0.jpg triplet.8a0.jpg triplet.9a0.jpg triplet.11a0.jpg triplet.12a0.jpg triplet.13a0.jpg

Raw images from the Huygens probe descent ESA page 2 (Of 37)

Second Titan Targeted Flyby #3
Second Titan Targeted Flyby

This view from Cassini's second close flyby of Titan on Dec. 13, shows bright material within the large dark region west of Xanadu. The area in this image is a region that has not previously been seen at this high resolution. The image was taken with the narrow angle camera at a distance of approximately 125,900 kilometres from Titan, using a filter centred at 938 nanometres that emphasizes the moon's surface and clouds. The image scale is 735 meters per pixel.

Goldstone Apple Valley Radio Telescope
Goldstone Apple Valley Radio Telescope
Direct radio signals from Huygens reached Earth after 67 minutes (travelling at the speed of light). An experiment had been set up by radio scientists to use an array of radio telescopes around the Pacific to detect a faint tone from Huygens. This was successful, early detection a faint carrier signal was received at 1038 GMT, by the Green Bank radio telescope in West Virginia, US, soon after it entered Titan's atmosphere.

Yes, click this! for computer-rendered views from the Cassini

Viewing the first Data
Viewing the first Data
Events Time Line

Saturday 25 December

Spacecraft operations will be run at NASAs Jet Propulsion Laboratory (JPL) in Pasadena, California.

05:08 CET - 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

17:00-17:30 CET - Press briefing at ESA/ESOC Control Centre in Darmstadt, Germany. Televised on ESA TV

Friday 14 January

Control room clock
Control room clock

Media briefings originated at ESA/ESOC will also be retransmitted to several ESA establishments and across Europe.

ESA TV Broadcast schedule for 14 January 2005

Announcement
Announcement of success

09:00-09:30 CET - ESA TV broadcast - Cassini turns to Huygens - Feeds from ESA/ESOC main Control Room.
11:00-12:15 CET - ESA TV Broadcast - Probe activation to parachute deployment and status of tracking by radio-telescope.
13:30-14:00 CET - Press briefing at ESA/ESOC: Huygens descent update (with results from ground radio telescope observations televised on ESA TV
14:30-15:00 CET - ESA TV broadcast: mission update.
16:00-16:30 CET - ESA TV broadcast: mission update.
As of 17:15 CET - Press briefing: arrival of first data televised on ESA TV.
23:00-24:00 CET - Press briefing: presentation of first image if available) - Televised on ESA TV

Time (GMT) `Earth Received`Events All times are 67 minutes after the actual events have taken place .
5.51 Timer triggers power-up of onboard electronics
Triggered by a pre-set timer, Huygens's onboard electronics power up and the transmitter is set into low-power mode, awaiting the start of transmission.
10.13 Huygens reaches 'interface altitude'
The 'interface altitude' is defined as 1270 kilometres above the surface of the moon where entry into Titan's atmosphere takes place. Over the next three to four minutes, the probe is expected to endure peak heating of nearly 3,500 degrees and a braking force of some 16 Gs, slowing the craft to 895 mph.
10.17 Pilot parachute deploys
The parachute deploys when Huygens detects that it has slowed to 400 metres per second, at about 180 kilometres above Titan's surface. The small 2.6 metres pilot parachute is the probe's smallest, its sole purpose is to pull off the probe's rear cover, which protected Huygens from the frictional heat of entry.

2.5 seconds after the pilot parachute is deployed, the rear cover is released and the pilot parachute is pulled away. The main parachute, which is 8.3 metres in diameter, unfurls.
10.18 Huygens begins transmitting to Cassini and front shield released
At about 160 kilometres above the surface, the front shield is released.

42 seconds after the pilot parachute is deployed, inlet ports are opened up for the Gas Chromatograph Mass Spectrometer and Aerosol Collector Pyrolyser instruments, and booms are extended to expose the Huygens Atmospheric Structure Instruments.

The Descent Imager/Spectral Radiometer will capture its first panorama, and it will continue capturing images and spectral data throughout the descent. The Surface Science Package will also be switched on, measuring atmospheric properties.
10.32 Main parachute separates and drogue parachute deploys
The drogue parachute is 3 metres in diameter. At this level in the atmosphere, about 125 kilometres in altitude, the large main parachute would slow Huygens down so much that the batteries would not last for the entire descent to the surface. The drogue parachute will allow it to descend at the right pace to gather the maximum amount of data.
10.49 Surface proximity sensor activated
Until this point, all of Huygens's actions have been based on clock timers. At a height of 60 kilometres, it will be able to detect its own altitude using a pair of radar altimeters, which will be able to measure the exact distance to the surface. The probe will constantly monitor its spin rate and altitude and feed this information to the science instruments. All times after this are approximate.
11.57 Gas Chromatograph Mass Spectrometer begins sampling atmosphere
This is the last of Huygens's instruments to be activated fully. The descent is expected to take 137 minutes in total, plus or minus 15 minutes. Throughout its descent, the spacecraft will continue to spin at a rate of between 1 and 20 rotations per minute, allowing the camera and other instruments to see the entire panorama around the descending spacecraft.
12.30 Descent Imager/Spectral Radiometer lamp turned on
Close to the surface, Huygens's camera instrument will turn on a light. The light is particularly important for the 'Spectral Radiometer' part of the instrument to determine the composition of Titan's surface accurately.
12.34 Surface touchdown
This time may vary by plus or minus 15 minutes depending on how Titan's atmosphere and winds affect Huygens's parachuting descent. Huygens will hit the surface at a speed of 5-6 metres per second. Huygens could land on a hard surface of rock or ice or possibly land on an ethane sea. In either case, Huygens's Surface Science Package is designed to capture every piece of information about the surface that can be determined in the three remaining minutes that Huygens is designed to survive after landing.
Scientists may get a
near-real time confirmation the probe survived the initial phases of its descent from large radio telescopes that will be monitoring the descent from Earth. No data will be received, but a carrier signal may be barely detectable.
14.44 Cassini stops collecting data
Huygens's landing site drops below Titan's horizon as seen by Cassini and the orbiter stops collecting data. Cassini will listen for Huygens's signal as long as there is the slightest possibility that it can be detected. Once Huygens's landing site disappears below the horizon, there's no more chance of signal, and Huygens's work is finished.
15.14 First data sent to Earth
Cassini first turns its high-gain antenna to point towards Earth and then sends the first packet of data.

Getting data from Cassini to Earth is now routine, but for the Huygens mission, additional safeguards are put in place to make sure that none of Huygens's data are lost. Giant radio antennas around the world will listen for Cassini as the orbiter relays repeated copies of Huygens data.
15.17 Probe data replay begins
Canberra radio dish receives at 66,360 bps.
17:57 End playback of first partition
18:04 Ascending ring-plane crossing
Cassini now at 18.4 Saturn radii.
19:00 Madrid radio dish starts tracking
142,200 bps data stream
22:07 End of first full playback of all Probe data


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and cover an area extending out to 30 kilometres.

8 kilometres above the surface  titan

8 kilometres above the surface
( Full Size Image)

Image Credit: ESA
The image is assembled from a number of Descent Imager Spectral Radiometer images. The vantage point was about 8 kilometres above the surface.

"There's no evidence yet of liquid in these rivers, they look more like Arizona's dried-up river beds. But those canyons didn't carve themselves."


Titan's surface is remarkably fresh. Counting the number of craters and comparing it with the number of meteoroids that cross the orbit gives astronomers a way to calculate the age of the surface. The younger the crust, the fewer craters are visible.
And there seems to be no craters; so it's probably less than 10 million years old .
Landing  panorama
Huygens panorama of titan
(
Full Size Image)
Image Credit: ESA

A panorama of the surface. Scientists speculate that the white streaks are a ground 'fog' of methane or ethane vapour

wimdows player from NPR.org

Yes, click this! click here for interactive panorama

Landing
Huygens on the Ground
Image Credit: NASA/JPL
An artist's impression of the Huygens probe on the surface of Titan.

Huygens is going to descend during `daylight hours`. Sunlight filtering through the casts an orange glow across the landscape "like 1000 full moons, and bright enough to read a newspaper, but still about 1000 times dimmer than a sunlit day on Earth.
Just before Huygens lands it will turn on an intense flashlight to shine onto the terrain below. This is done to improve pictures of the landing site and help the probe's spectrometers get better readings of elements and minerals in the soil.
"The gods smiled on us." - ESA's space science director David Southwood,

spacer.gifHuygens landing site

Landing Site
(Full Size Image)

This map illustrates the planned imaging coverage for the Descent Imager/Spectral Radiometer, onboard the European Space Agency's Huygens probe during the probe's descent toward Titan's surface on Jan. 14, 2005.
The coloured lines delineate regions that will be imaged at different resolutions as the probe descends. On each map, the site where Huygens is predicted to land is marked with a yellow dot. This area is in a boundary between dark and bright regions.
Yes, click this! to read more
huygensentry.jpg
Huygens entry
The `descent octagons` indicate fields of view of the panoramic mosaics of images taken by Huygens' descent imager and spectral radiometer instrument as the probe reaches certain altitudes during its descent. This map shows the footprints for mosaics to be assembled from 36 individual images at each altitude, with the field of view cut off at 75 degrees from straight down although the actual images will extend all the way to the hazy horizon. Each mosaic made this way will be about 1,300 by 1,300 pixels.

The largest octagon is about 1,120 kilometres across and represents the field of view for the mosaic of images taken at an altitude of 150 kilometres. From that height, individual pixels in the centre of the image will be about 150 meters across, though haze between the ground and the camera at that height will likely degrade the resolution in those images.

Clck to download
Taken altitude of 8 kilometres with a resolution of 20 metres per pixel.

The progressively smaller octagons are the anticipated fields of view from altitudes of 90 kilometres, 50 kilometres and 30 kilometres. In all, the camera is expected to acquire panoramic mosaics at a total of 20 different altitudes from 150 kilometres down to about 3 kilometres. The pixel size in the mosaic from 3 kilometres high will be about 3 meters across. In addition, the camera is expected to obtain individual images down to an altitude of about 200 meters with pixel size as small as 20 centimetres. The location of the anticipated landing site is based on modelling of Titan's winds, and the actual landing site will be different if the actual winds experienced by Huygens during descent differ from this model.

Landing Site:
Titan close-up
The first flyby of Titan took place on 3 July 2004. It provided data on Titan's atmosphere which was confirmed by another close flyby on 26 October 2004 at an altitude of 1174 km of this moon at a speed of 13.8 kilometres per second. At this distance the narrow-angle camera was able to resolve features down to about 1.4 kilometres in size. These data were used to validate the entry conditions of the Huygens probe. Another close flyby of Titan at an altitude of 1200 km occurred on 13 December and provided additional data to further validate the entry conditions of the Huygens probe.

On 17 December the orbiter was placed on a controlled collision course with Titan in order to release Huygens on the proper trajectory, and on 21 December all systems were set up for separation and the Huygens timers set to wake the probe a few hours before its arrival at Titan.

TheProbeHasLanded!
Huygens discarding heat shield
Huygens discarding heat shield

The Huygens probe separated on the morning of 25 December at about 02:00 UTC (03:00 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. This signal then took 1 hour and 8 minutes to cross the 1.2 billion kilometres separating the Cassini spacecraft and Earth. Separation was achieved by the firing of pyrotechnic devices. Under the action of push-off springs, ramps and rollers, the probe was released at a relative velocity of about 35 cm per second, and, to keep on track, will spin on its axis, making about 7 revolutions a minute.

Huygens drifted through space until it hits Titan's atmosphere on January 14 at about 1013 GMT moving at 10 miles a second. The dense air encountered by the probe rapidly slowed it down, allowing Huygens to drift downward under a deployed parachute for almost three hours.
During the descent onto Titan, the Huygens probe scanned the surrounding atmosphere to analyse its composition and take more than 1,000 images as it heads toward the surface.

Huygens entered Titans atmosphere at a relatively steep angle of 65 and a velocity of about 6 km/s. The target was over the southern hemisphere, on the day side. Protected by an ablative thermal shield, the probe decelerated to 400 m/s within 3 minutes before it deploys a 2.6 m pilot chute at about 160 km. After 2.5 seconds this chute pulled away the probes aft cover and the main parachute, 8.3 m in diameter, was deploy to stabilise the probe. The front shield was then released and the probe, whose main objective is to study Titans atmosphere, opened inlet ports and deploy booms to collect the scientific data. All instruments will have direct access to the atmosphere to conduct detailed in-situ measurements of its structure, dynamics and chemistry. Imagery of the surface along the track was also acquired. The Descent Imager/Spectral Radiometer took pictures as the probe slowly spins. These data was transmitted directly to the Cassini orbiter, which, at the same time, will be flying over Titan at 60 000 km at closest approach. Earth-based radio telescopes have detect the signals tone directly.

15 minutes into the descent, at about 120 km, Huygens released its main parachute and a smaller 3 m drogue chute which took over to allow a deeper plunge through the atmosphere within the lifetime of the probes batteries.

The descent lasted about 140 minutes before Huygens impacted the surface at about 6 m/s. The probe has survives all this, and its extended mission will start, consisting in direct characterisation of Titans surface for as long as the batteries can power the instruments and the Cassini orbiter is visible over the horizon at the landing site, i.e. not more than 130 minutes.

Titan Raindrops
Titan Raindrops

At that time, the Cassini orbiter reoriented its main antenna dish toward Earth in order to play back the data collected by Huygens, which will be received by NASAs 70-m diameter antenna in Canberra, Australia, 67 minutes later. Three playbacks are planned, to ensure that all recorded data are safely transmitted to Earth. Then Cassini will continue its mission exploring Saturn and its moons, which includes multiple additional flybys of Titan in the coming months and years.

Quicktime MOVIEof descent.( 1.9Mb .Mov)

The Huygens probe separating from the Cassini spacecraft
Huygens separates from Cassini

After release, Huygens did not communicate with Cassini for the whole period until after deployment of the main parachute following entry into Titans atmosphere. Titan's atmosphere, which is about 95% nitrogen and 5% methane, has a pressure near the surface that is one and a half times the Earth's sea level pressure.

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, to later relay back to Earth.

infrared Titan
Titan close-up

These images show the surface of Titan at two different infrared wavelengths. They were captured by the visual and infrared mapping spectrometer onboard Cassini as the spacecraft flew by at an altitude of 1200 kilometres - Cassini's closest approach yet to the hazy moon. The image on the left, taken at a wavelength of 2 microns, is the most detailed picture to date of the Titan's surface. It reveals complex landforms with sharp boundaries, which scientists are eager to further study. The image on the right was taken at a wavelength of 1 micron and shows approximately what a digital camera might see. It seems from the pictures received that this area is geologically alive, possibly with liquids moving on its surface.

Titan ice flows
No evidence of oceans?

However, synthetic aperture radar images of the surface, captured on Oct. 26, when the Cassini spacecraft flew approximately 2,500 kilometres above the surface, show that the dark regions may represent areas that are smooth, made of radar-absorbing materials, or are sloped away from the direction of illumination. A striking bright feature stretches from upper left to lower right across this image, with connected 'arms' to the East. The fact that the lower (southern) edges of the features are brighter is consistent with the structure being raised above the relatively featureless darker background. Comparisons with other features and data from other instruments has determined that this is a cryovolcanic flow, where water-rich liquid has welled up from Titan's warm interior.
Previous Photometric profiles showed considerable variations across dark areas that were identified as possible lakes or seas. A liquid surface would have been more uniform.
"There is no evidence of oceans,"
But it turns out that there is hydrocarbon flows and lakes.
Most of the features seem to be volcanic in nature, produced by flowing ice rather than molten rock.

"It looks like something has flowed at some time to make those channels. But is it something that has solidified?"

View from ten miles up:Seen are streams, valleys and to the right a coastline.

Huygens remained dormant until a few hours before its arrival at Titan on 14 January. The entry into the atmosphere is set for 11:13 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, a solid surface, it could, in theory, deliver up to 2 hours of bonus data before the link with Cassini is lost. If Huygens lands in a liquid, ultra-low temperatures will sap the craft's batteries faster. "If it's not a sea, it could be a lake of tar. And did one see waves?" As a bonus the craft had been active for up to seven hours; due to the probe`s design keeping Huygens' instruments warmer than expected. The total data received would fit onto 3 floppy disks.
drainage channels
Titan drainage channels
Tidal Basin ? ( Titans orbit period of 15.95 days, and the moons position relative to Saturn would mean that the `tide` was rising.)

Titans orbit period of 15.95 days, and the moons position relative to Saturn would mean that the `tide` was rising.

"It looks like something has flowed at some time to make those channels. But is it something that has solidified?"

The drainage channels were either caused by falling rain or seepage of liquid hydrocarbons similar to lighter fuel or natural gas (CH4) which had soaked into the ground.



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On Christmas day Huygens began its final journey to Titan

PAGE TWO- arrowleft.gif


At 1.25 billion kilometres from Earth, and after a 7-year journey, ESAs Huygens probe separated from the Cassini orbiter to fall towards Titan, the largest moon of Saturn, to enter its atmosphere on 14 January 2005, 1013 GMT, and
landing on the surface at 1234 GMT.

This was the first man-made object to land on a this strange world, whose chemistry was assumed to be very similar to that of the early Earth just before life began, 3.8 billion years ago.

WATCH!Lord of the Rings: January 2005
Patrick Moore discusses the spacecraft Cassini, which has been at Saturn for six months, and Cassini's probe Huygens, which was sent to Titan.
Titan 'TB' Flyby Animation
Saturn orbit insertion manoeuvre
The Cassini-Huygens spacecraft, a joint mission conducted by NASA, ESA and the Italian space agency (ASI), was launched into space on 15 October 1997, and took almost 7 years for the to reach Saturn, with the help of several gravity assist manoeuvres during flybys of Venus, Earth and Jupiter.

The Cassini orbiter, carrying the Huygens strapped to its belly, entered orbit around Saturn on 1 July 2004, and began a four year mission to explore strange new worlds.
The Cassini space probe carries two cameras, one with a narrow angle (0.35 degrees field of view) and the other with a wide angle (3.5 degrees).

PAGE TWO-New Results arrowleft.gif
Cassini's View of Titan Landing Site
Cassini's View of Titan Landing Site
Mosaic of River Channel and Ridge Area on Titan
Mosaic of River Channel and Ridge Area on Titan
Water Ice and Methane Springs on Titan
Water Ice and Methane Springs on Titan
Possible 'Islands' on a Dark Plain
Possible 'Islands' on a Dark Plain
Yes, click this! click here for interactive panorama
spacer.giftitanmosaicfalsecolorb.jpg

Landing Site false colour
(Full Size Image)

Both cameras use charge coupled devices (CCDs), which are silicon chips that change photons of light into electronic signals to create images or to analyse the light received from such objects. Both cameras are equipped with dozens of filters operating between ultraviolet and near-infrared wavelengths. They are ideal for examining the atmosphere of Titanand showing close-up details of the moon's surface.

This image shows a full 360-degree view around Huygens. The left-hand side, behind Huygens, shows a boundary between light and dark areas. The white streaks seen near this boundary could be ground 'fog' of methane or ethane vapour, as they were not immediately visible from higher altitudes. As the probe descended, it drifted over a plateau (centre of image) and was heading towards its landing site in a dark area (right). This dark area is possibly a drainage channel which might still contain liquid material. From the drift of the probe, the wind speed has been estimated at around 6-7 metres per second.

spacer.gifprobelandingsite.jpg

Landing Site Location

A view of Huygens probable landing site based on initial, best-guess estimates. Scientists on the Huygens Descent Imager/ Spectral Radiometer (DISR) science team are still working to refine the exact location of the probe's landing site, but they estimate that it lies within the white circle shown in this image.
In some areas, the surface is very bright. This suggests that liquids wash dark tars from the icy surface quite regularly. This might be a sign of methane rain.

Geothermal activity from underground heat sources on titan may generate methane through the oxidation of iron contained in hot basaltic rocks. The process releases hydrogen which combines with carbon to form methane.

spacer.gifpolar panorama

Landing polar panorama
(Full Size Image)

spacer.gifHuygens landing site

The `Airstrip` Detail

Landing Site:
Titan Total surface (2)

Click to Expand the Images!

This is an improved (Better than the ESA offering below) image of the surface.

8 kilometres above the surface  titan

8 kilometres above the surface
( Full Size Image) 216 kb

Image Credit: ESA
This is a ESA website picture is a composite of 30 images from ESA's Huygens probe, released on Jan 17th. They were taken from an altitude varying from 13 kilometres down to 8 kilometres when the probe was descending towards its landing site.
At that stage of its descent, Huygens was dropping almost vertically with a speed of about 5 metres per second. It was drifting horizontally with a speed of about 1 metre per second.

These images were taken with a resolution of about 20 metres per pixel and cover an area extending



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Huygens probe
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A billion miles from Earth, a small saucer-shaped spacecraft emerged from the fiery turmoil of an atmospheric entry.
Seconds later, a set of explosive bolts fired, and its charred heat-shield fell away. A parachute then opened and the craft slowly began its descent, gently buffeted by winds.
With temperatures hovering at a chilly -180C, it finally touched down on the freezing surface of this distant world.
Not the opening chapter of a science fiction novel, but an accurate description of the extraordinary moment on 14 January 2005 when the European Space Agency's Huygens probe landed on the surface of Saturn's largest moon, Titan.

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The Huygens probe, supplied by the European Space Agency (ESA) and named after the Dutch 17th century astronomer Christiaan Huygens, was an atmospheric entry probe carried to Saturn's moon Titan as part of the Cassini-Huygens mission. The combined Cassini-Huygens spacecraft was launched from Earth on October 15, 1997. Huygens separated from the Cassini orbiter on December 25, 2004, and landed on Titan on January 14, 2005 near the Xanadu region.

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Animated artist's interpretation of the area surrounding the Huygens landing site based on images & data returned Jan 14 2005 (Titan's chemistry may be similar to that of earths 400 million years ago).



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