posted November 24, 2004 06:53 AM            

A good fore-taste for Huygens.

posted December 14, 2004 05:07 PM            

I think that Titan will turn out to be very much like Io's surface but with an atmospheric attitude! I think the surface will be hardish volcanics covered with a dusty layer - we can just about see volcanoes with ash tales (suggesting a particular wind direction?) and what appears to be a few impact craters. (There are some image defects which have to be taken into account.) The dark areas I think are likely be igneous materials like basalts.

But, whatever surface turns out to be, its all good stuff so far.

posted December 14, 2004 06:09 PM            

quote:

---

Originally posted by spaceuk:
Whose delivering Huygens - Santa?

---

Cassanta?

posted December 24, 2004 11:08 PM               

Huygens away!

The European Space Agency's Huygens probe successfully detached from NASA's Cassini orbiter today to begin a three-week journey to Saturn's moon Titan. NASA's Deep Space Network tracking stations in Madrid, Spain and Goldstone, Calif., received the signal at 7:24 p.m. (PST). All systems performed as expected and there were no problems reported with the Cassini spacecraft.

The Huygens probe, built and managed by the European Space Agency, was bolted to Cassini and has been riding along during the nearly seven-year journey to Saturn largely in a "sleep" mode. Huygens will be the first human-made object to explore on-site the unique environment of Titan, whose chemistry is assumed to be very similar to that of early Earth before life formed. Huygens will tell us whether this assumption is correct.

"We wish to congratulate our European partners as their journey begins and wish them well on their descent to Titan," said Robert T. Mitchell, Cassini program manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We are very excited to see the probe off and to have accomplished this part of our job. Now we're ready to finish our part -- receiving and relaying the Huygens data back to Earth."

"Today's release is another successful milestone in the Cassini-Huygens odyssey," said Dr. David Southwood, director of science program for the European Space Agency. "This was an amicable separation after seven years of living together. Our thanks to our partners at NASA for the lift. Each spacecraft will now continue on its own but we expect they'll keep in touch to complete this amazing mission. Now all our hopes and expectations are focused on getting the first in-situ data from a new world we've been dreaming of exploring for decades."

The Huygens probe will remain dormant until the onboard timer wakes it up just before the probe reaches Titan's upper atmosphere on Jan. 14, 2005. Then it will be begin a dramatic plunge through Titan's murky atmosphere, tasting its chemical makeup and composition as it descends to touch down on its surface. The data gathered during this 2-1/2 hour descent will be transmitted from the probe to the Cassini orbiter. Afterward, Cassini will point its antenna to Earth and relay the data through NASA's Deep Space Network to JPL and on to the European Space Agency's Space Operations Center in Darmstadt, Germany, which serves as the operations center for the Huygens probe mission. From this control center, ESA engineers will be tracking the probe and scientists will be standing by to process the data from the probe's six instruments.

On Monday, Dec. 27, the Cassini orbiter will perform a deflection maneuver to keep it from following Huygens into Titan's atmosphere. This maneuver will also establish the required geometry between the probe and the orbiter for radio communications during the probe descent.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Science Mission Directorate, Washington, D.C. JPL designed, developed and assembled the Cassini orbiter. The European Space Agency built and managed the development of the Huygens probe and is in charge of the probe operations. The Italian Space Agency provided the high-gain antenna, much of the radio system and elements of several of Cassini's science instruments.

posted December 30, 2004 11:00 AM            

The images of Huygen some distance from Cassini seemed to evoke Newton's First Law exquisitely for me :

"A body (Huygen) continues in its state of motion in a straight line unless it is subjected to a force (Titan's atmosphere)."

posted January 09, 2005 06:03 PM            

Huygens Descent and Landing
14th Jan 2005

0907 GMT - Arrival of Huygens probe at entry interface at an altitude 1270 km. Data acquisition starts.

1130 GMT - Huygens probe reaches Titans surface. Data acquisition continues. Huygens data transmitted to Cassini orbiter. Once all the Huygens probe data has been recorded on the orbiter it is transmitted to Earth.

1344 GMT - The orbiter will stop collecting probe data and point back to Earth. Complete data sets transmitted to JPL (via NASA Deep Space Network (Madrid and Canberra ground stations) repeated several times - and forwarded to ESOC. It takes approx. 66 minutes for the radio signal to reach Earth.

1514 GMT First telemetry received at JPL

1521 GMT First data received at ESOC from JPL.

1500 GMT PPARC Media briefing opens Reprise ESA TV transmissions, direct links to UK scientists at ESOC, live relay of ESA/ESOC Media briefing

1600/1700 GMT ESA/ESOC Media briefing: first data information

1900 GMT - PPARC Media briefing closes

2200 GMT, the first image possibility, subject to full data receipt and processing. If available then ESA press release and posted to ESA website.

15th January

1000 GMT ESA/ESOC Press briefing: comprehensive first results and images.

NB: All ESA press briefings will be available on ESA TV and are subject to confirmation on ESA TV web pages.

posted January 10, 2005 02:17 PM               

I ask because I remember watching a live programme on the Giotto encounter with Halley's Comet back in 1986 and it was the most boring programme imaginable. As the images took weeks to process and enhance so any details could be visible, all we saw was a grey screen. No-one knew anything about the state of the probe, and the presenters had no idea what to say or how to manage the viewers expectations.

Hopefully things have moved on since then, but the same limitations are going to apply. Even if signals are recieved back what will we actually see?

Am I being pessimistic?

posted January 10, 2005 02:23 PM               

Live from another world
by Daniel Fischer

Nothing remotely like the Voyager, Pathfinder, or MER experience is about to repeat when Huygens lands on Titan, according at least to the current plans by the European Space Agency. The incoming raw images for the DISR cameras will only be seen by the scientists directly involved in the project: They will work on them and release them only hours later, after much processing of contrast and resolution. A few glimpses of the DISR images may be shown some hours after they arrived, but the majority of them, plus all the other data collected during the descent, are only to be released during a news briefing the next day. Now it is understandable that the European Space Agency wants to release only the best material, but to deprive the public of the chance to experience the mission as it happens (or happened) is a major blunder.

posted January 12, 2005 12:28 PM            

The effects of which refractions are very remarkable; for by them we often see objects which the rotundity of the Earth ought otherwise to hide; such as islands and the tops of mountains when one is at sea.

posted January 13, 2005 11:23 PM               

3-3:30 a.m. - Live Coverage and Commentary "Cassini Turns Towards Titan - Interruption of Radio Contact" - JPL/ESA

5-6:30 a.m. - Live Coverage and Commentary "The Huygens Probe Enters the Atmosphere of Titan" - JPL/ESA

6:30-7 a.m. - JPL Commentary - JPL (Mission Coverage)

7:30-8 a.m. - ESA News Briefing "Mission Status" - JPL/ESA

8:30-9:15 a.m. - ESA Commentary on Huygens Probe Mission - JPL/ESA (Mission Coverage)

9:30-10 a.m. - JPL Commentary - JPL (Mission Coverage)

10-10:30 a.m. - ESA Commentary "Cassini Turns Back to Earth - Data Transmission Begins" - JPL/ESA

10:30-11:15 a.m. - JPL Commentary - JPL (Mission Coverage)

11:15 a.m.-12 p.m. - Huygens Probe News Briefing - JPL/ESA (Mission Coverage)

1 p.m. - NASA Update with Sean O'Keefe - KSC

2:45-3:15 p.m. - ESA Commentary "Presentation of First 18 Images from Titan" - JPL/ESA (Mission Coverage)

5-5:30 p.m. - ESA Commentary and "Additional Images from Tital & B-Roll" - JPL/ESA

posted January 14, 2005 01:56 AM            

But, of course, today - Friday the 14th January 2005 - is an important day for one of Saturn's many moons - the moon of Titan. If I was observing it through my telescope I would be able to see that Saturn was tilted and showing off its beautiful rings and that the moon Titan would be about 0.008 AU and at an angular separation of just under 2 minutes from Saturn. It is just over 8 AU from my observing site here on Earth.

And, today Titan it will receive its first visitor from Earth - the Huygen's probe.

It is also an "important" day for myself and my family as we eagerly await news later this afternoon - when the first signals arrive - that we hope to hear that the Huygen's probe successfully descended through Titan's atmosphere and survived to land onto its surface. For, aboard the probe, myself and family members have our names on the CD disk that is attached to the probe as its descends. It seems aeons ago on the 20th January 1997 - since I applied and successfully had our names accepted by ESA. Originally, Huygens was intended for a late 2004 descent to Titan but flight plan adjustments made today the descent day.

While reviewing the flight plan for the descent of Huygen's through the atmosphere of Titan later this morning (GMT time) I began to wonder what music I would have played to the Titanian's (if they existed!) from a loud speaker had it been attached to Huygen's as it descended? [see note below]

There are the classical offerings from composers like Beethoven, Mozart and even Brahms! But, in the end, I decided I would have played a more modern offering - the orchestral and bagpipe version of Paul McCartney's "Mull of Kintyre". The swirl of the bagpipes to me seems an ideal choice for the swirling murky mists of Titan as well as the mists of the Mull of Kintyre. If you have ever heard bagpipes being played in dusk in the hills and valleys of Scotland the haunting sounds never seem to 'leave' you! The sound seems to carry for miles and miles and seems to be 'magically mixed' with the misty air. The sounds will reverberate off nearby hills and 'swish' amongst the heather's on the slopes. So, for me, it is this music that I would have played on the descent.

Incidentally, just for the hell of it, I will play my CD version of 'Mull of Kintyre' later today here on Earth as a substitute.

Other contenders in my mini list were orchestral versions of Frank Sinatra's "My Way" or Andrew Lloyd Webber's orchestral version of "Phantom of the Opera"!

posted January 14, 2005 06:23 AM            

The normally staid news readers at BBC TV News were excited this morning!

posted January 14, 2005 09:51 AM               

Radio astronomers confirm Huygens entry in the atmosphere of Titan

At 11:25 CET the Robert C. Byrd Green Bank Telescope (GBT) of the National Radio-astronomy Observatory in West Virginia, USA, a part of the global network of radio telescopes involved in tracking the Huygens Titan probe, has detected the probe's 'carrier' (tone) signal.

The detection occurred between 11:20 and 11:25 CET, shortly after the probe began its parachute descent through Titan's atmosphere. The extremely feeble signal was first picked up by the Radio Science Receiver supplied by the NASA Jet Propulsion Laboratory. This signal is an important indication that the Huygens probe is 'alive'. However, it does not contain yet any substance; the latter is expected to come a few hours later via the Cassini spacecraft.

What the Green Bank radio telescope has detected is only a 'carrier' signal. It indicates that the back cover of Huygens must have been ejected, the main parachute must have been deployed and that the probe has begun to transmit, in other words, the probe is 'alive'. This, however, still does not mean that any data have been acquired, nor that they have been received by Cassini. The carrier signal is sent continuously throughout the descent and as such does not contain any scientific data. It is similar to the tone signal heard in a telephone handset once the latter is picked up.

Only after having received the data packets at ESOC will it be possible to say with certainty whether data were properly acquired. The first data set from Cassini will reach ESOC in the afternoon. Additional downlinks will follow throughout the evening and night for redundancy.

Further analysis of the signals will be conducted using other three independent data acquisition systems at the Green Bank Telescope. In addition to the GBT, sixteen other radio telescopes in Australia, China, Japan and the USA are involved in tracking the Huygens probe.

The ultimate goal of the tracking experiment is to reconstruct the probe's descent trajectory with an unprecedented accuracy of the order of one kilometre. The measurements will be conducted using Very Long Baseline Interferometry (VLBI) and Doppler tracking techniques. This would enable studies of the dynamics of Titan's atmosphere, which is considered to be a 'frozen' copy of that of the early Earth.

The VLBI component of the tracking experiment is coordinated by the Joint Institute for VLBI in Europe (JIVE) and ESA; the Doppler measurements are conducted by the Jet Propulsion Laboratory.

posted January 14, 2005 10:21 AM               

Huygens has arrived.

The probe landed on the surface of Saturn's moon Titan this morning around 7:45 ET, reported elated scientists from the European Space Agency, who are eagerly awaiting data about the cloud-shrouded moon.

"We have a signal. We know that Huygens is alive meaning the dream is alive," said Jean-Jacques Dordain director general for ESA which designed Huygens. "This is already an engineering success and we will see, later this afternoon, if this is a scientific success."

"This is clearly an engineering success and we know the probe has been successfully entering the atmosphere, has been descending on the parachute to the surface," said Jean-Pierre Lebreton, ESA's Huygens project scientist.

"But at this moment we cannot say more. I mean, we have not seen the data. What we have seen is a tone, a signal, which was indicating that the probe was transmitting but we have not seen any real data yet. So I would like to wait a bit more to say whether we have a successful mission or not."

The first Huygens data via the Cassini telemetry playback is expected in about an hour.

posted January 14, 2005 12:03 PM               

..and this is NOT the first European success. It comes on top of Mars Express, SMART 1, and hopefully Rosetta and Venus Express. I just wish my country (UK) played a more substantial role.

posted January 14, 2005 12:10 PM               

First Landing, Outer Solar System

Today, after its seven-year journey through the Solar System on board the Cassini spacecraft, ESA's Huygens probe has successfully descended through the atmosphere of Titan, Saturn's largest moon, and safely landed on its surface.

The first scientific data arrived at the European Space Operations Centre (ESOC) in Darmstadt, Germany, this afternoon at 17:19 CET. Huygens is mankind's first successful attempt to land a probe on another a world in the outer Solar System. "This is a great achievement for Europe and its US partners in this ambitious international endeavour to explore the Saturnian system," said Jean-Jacques Dordain, ESA's Director General.

Following its release from the Cassini mothership on 25 December, Huygens reached Titan's outer atmosphere after 20 days and a 4 million km cruise. The probe started its descent through Titan's hazy cloud layers from an altitude of about 1270 km at 11:13 CET. During the following three minutes Huygens had to decelerate from 18 000 to 1400 km per hour.

A sequence of parachutes then slowed it down to less than 300 km per hour. At a height of about 160 km the probe's scientific instruments were exposed to Titan's atmosphere. At about 120 km, the main parachute was replaced by a smaller one to complete the descent, with an expected touchdown at 13:34 CET. Preliminary data indicate that the probe landed safely, likely on a solid surface.

The probe began transmitting data to Cassini four minutes into its descent and continued to transmit data after landing at least as long as Cassini was above Titan's horizon. The certainty that Huygens was alive came already at 11:25 CET today, when the Green Bank radio telescope in West Virginia, USA, picked up a faint but unmistakable radio signal from the probe. Radio telescopes on Earth continued to receive this signal well past the expected lifetime of Huygens.

Huygens data, relayed by Cassini, were picked up by NASA's Deep Space Network and delivered immediately to ESA's European Space Operation Centre in Darmstadt, Germany, where the scientific analysis is currently taking place.

"Titan was always the target in the Saturn system where the need for 'ground truth' from a probe was critical. It is a fascinating world and we are now eagerly awaiting the scientific results," says Professor David Southwood, Director of ESA's scientific programmme.

"The Huygens scientists are all delighted. This was worth the long wait," says Dr Jean-Pierre Lebreton, ESA Huygens Mission Manager. Huygens is expected to provide the first direct and detailed sampling of Titan's atmospheric chemistry and the first photographs of its hidden surface, and will supply a detailed 'weather report'.

One of the main reasons for sending Huygens to Titan is that its nitrogen atmosphere, rich in methane, and its surface may contain many chemicals of the kind that existed on the young Earth. Combined with the Cassini observations, Huygens will afford an unprecedented view of Saturn's mysterious moon.

"Descending through Titan was a once-in-a-lifetime opportunity and today's achievement proves that our partnership with ESA was an excellent one," says Alphonso Diaz, NASA Associate Administrator of Science.

The Cassini-Huygens mission is a cooperation between NASA, the European Space Agency 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's Office of Space Science, Washington. JPL designed, developed and assembled the Cassini orbiter.

"The teamwork in Europe and the USA, between scientists, industry and agencies has been extraordinary and has set the foundation for today's enormous success," concludes Jean-Jacques Dordain.