Glimpses of Titan’s Weather

The European Space Agency's Paris conference on the 21st gave us a further look at Titan's exotic weather systems. In particular, the Gas Chromatograph Mass Spectrometer carried by Huygens produced data showing the malleable nature of methane on the surface of the frigid world. According to John Zarnecki, principal investigator for the Huygens Surface Science Package: "The Gas Chromatograph Mass Spectrometer has detected a 'whiff' of methane evaporating off the surface and the SSP data has also shown indications of gas flowing into its sensing area. These gaseous outbursts were released as heat generated by Huygens warmed the soil beneath the probe. This is a tantalising glimpse of the processes at work on Titan and shows how the weather systems operate with methane forming clouds and raining down on to the surface - producing the drainage channels, river beds and other features that we see in the images." And back to that 'creme brulee' comparison -- Huygens' penetrometer evidently...

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Remembering Olaf Stapledon

"Sooner or later for good or ill, a united mankind, equipped with science and power, will probably turn its attention to the other planets, not only for economic exploitation, but also as possible homes for man... The goal for the solar system would seem to be that it should become an interplanetary community of very diverse worlds ... each contributing to the common experience its characteristic view of the universe. Through the pooling of this wealth of experience, through this "commonwealth of worlds," new levels of mental and spiritual development should become possible, levels at present quite inconceivable to man." -- Olaf Stapledon, in a 1948 address to the British Interplanetary Society. Centauri Dreams note: Both C. S. Lewis and Arthur C. Clarke have acknowledged their debt to Stapledon, the British philosopher and science fiction writer whose Last and First Men (1930) and Starmaker (1937) project the human story forward into the remotest of futures. For myth-making,...

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Findings Challenge Definition of Brown Dwarfs

New photos from the Very Large Telescope at Paranal in the Chilean Andes have made it possible to measure the mass of a young object orbiting the star AB Doradus A. The low-mass companion to the star has been under study since the early 1990s, when the characteristic wobble of the parent star suggested a faint companion, either a planet or a brown dwarf. Using a high-contrast camera equipped with adaptive optics, the University of Arizona's Laird Close has now brought home photographs and measurements of the companion known as AB Dor C (click on the image to enlarge). Image: ESO PR Photo 03/05 is an enhanced, false-colour near-infrared image of AB Dor A and C. The faint companion "AB Dor C" - seen as the pink dot at 8 o'clock - is 120 times fainter than its primary star. The tiny separation between A and C, only 0.156 arcsec, is smaller than a one Euro coin seen at 20 km distance. Nevertheless, the new NACO SDI camera was able to distinguish it as a "redder" dot surrounded by the...

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New Data Show Titan’s Complex Weather, Geology

ESA's Paris press conference produced new images and an analysis of data from the six instruments that Huygens took to the surface of Titan. "We now have the key to understanding what shapes Titan's landscape," said Dr Martin Tomasko, Principal Investigator for the Descent Imager-Spectral Radiometer (DISR), adding: "Geological evidence for precipitation, erosion, mechanical abrasion and other fluvial activity says that the physical processes shaping Titan are much the same as those shaping Earth." That statement appears in this ESA news release, which goes on to discuss the remarkable surface features Titan has yielded up to scrutiny. And while calling Titan an 'extraordinarily Earth-like world,' as ESA does here, seems to be stretching the point (especially at surface temperatures cold enough to produce liquid methane), the new images,like the one below, do show a complex meteorology. Available in both a gaseous and liquid state, methane forms clouds and precipitates onto the...

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Expect New Huygens Data Tomorrow

Huygens mission scientists will gather tomorrow in Paris to discuss the results of the experiments aboard the probe. Huygens delivered plenty of data: the probe transmitted for several hours from the surface of Titan, even after the Cassini orbiter moved below the horizon. Cassini received one hour and twelve minutes worth of solid information; all told, we have some 474 megabits that include 350 pictures of the descent and landing area. Early results show that the upper atmosphere is what the European Space Agency calls 'a uniform mix of methane with nitrogen in the stratosphere.' As the probe descended, the concentration of methane increased. One unexpected issue was the haze, which the Huygens team assumed the probe would clear at between 75 and 50 kilometers. In fact, Huygens only emerged from the haze at 30 kilometers above the surface. Methane or ethane fog was detected near the ground. On the table tomorrow in Paris will be data about the texture of Titan's surface (the famous...

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Matter Found Moving Close to Light Speed

In Blazing Speed: The Fastest Stuff in the Universe, Robert Roy Britt looks at recent studies of a form of matter that moves remarkably close to the speed of light. The material comes in the form of huge jets of hot gas that are ejected from a kind of galaxy called a blazar. Some of these jets attain speeds of 99.9 percent of the speed of light, according to a study presented at the recent AAS meeting by Glenn Piner of Whittier College in Whittier, California. Britt's article gives an overview of Piner's work, but dig deeper at Piner's Web site Quasar Research at Whittier College, where he explains the study's methodology, which used Very Long Baseline Interferometry. The technique combines data from widely separated telescopes to achieve the same angular resolution as a single telescope with a size equal to the maximum separation between the individual dishes. From a news release from Whittier: Blazars are active galactic nuclei -- energetic regions surrounding massive black holes...

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Planet Formation Around Nearby Red Dwarfs

M-class red dwarf stars are unusually interesting. For one thing, they make up 70 percent of all stars in our galaxy, meaning the great bulk of stars are much less massive than our Sun and far less bright, not to mention being considerably longer-lived. For another thing, the closest known star, Proxima Centauri, is a red dwarf, so anything we could learn about planetary formation there or around other nearby red dwarfs would be all to the good. But that's just it -- we know very little about what's happening around red dwarfs. Attempts to find planets around Proxima Centauri have thus far come up short. Best known is a 1994 study that was suggestive (but not conclusive), of a near Jupiter-sized planet orbiting closer than the distance of Mercury to our Sun. Later Hubble data was also no more than suggestive, while observations at the European Southern Observatory found no evidence for planets as large as Jupiter, though remaining moot on the question of smaller worlds. Image:...

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A Planetary Collision Near Beta Pictoris?

The dust disk around the star Beta Pictoris has been under study since 1983, when it was detected in IRAS (Infrared Astronomy Satellite) data. Last October, astronomers in Japan found three rings of planetismals circling the star, with a possible planet at 12 AU. Now the Gemini South 8-meter telescope in Chile has found telling new details in the disk. The upshot: a collision between large planetary bodies may have occurred there within the last few decades. This is intriguing news for those scientists who believe such collisions are a necessary part of planetary formation. From a Gemini Observatory news release: "It is as if we were looking back about 5 billion years and watching our own solar system as it was forming into what we see today," said Dr. Charles Telesco of the University of Florida who led the team. "Our research is a bit like a detective dusting for fingerprints to figure out a crime scene, only in this case we use the dust as a tracer to show what has happened within...

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New Images and Audio from Titan

Of all the Titan images released so far, this one may be the most provocative. Surely these are drainage channels, and is it possible we're looking at a coastline in the lower part of the picture? Is there still liquid out there? If so, it's not water but liquid methane or ethane, and it may have drained long ago into the surface. Months of analysis will be needed before we start getting answers to such questions. The image was taken at approximately 8 kilometers altitude. Note what may be fog near the 'shoreline.' Image: A boundary between high, lighter-coloured terrain and and darker lowland area on Titan. Credit: European Space Agency. More images from ESA are here. The Huygens Atmospheric Structure Instrument (HASI) recorded the sounds of Huygens' descent, now available online. A member of the HASI science team describes the descent audio as including a 'lot of acoustic noise,' which I assume refers to the sound you would have heard within the probe during the descent; the audio...

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Titan Images Reveal Complex Surface

The first images coming back from Titan are raw (i.e., unprocessed), and we'll have more (up to 350, apparently) available soon. The first picture shows what appear to be drainage channels, as you can see below. This is one of the first raw, or unprocessed, images from the European Space Agency's Huygens probe as it descended to Saturn's moon Titan. It was taken with the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe. Credit: ESA/NASA/University of Arizona The second image (via Emily Lakdawalla in Darmstadt) seems to be from the surface. Notice the rounded rocks, perhaps evidence of erosion from some kind of liquid (though I notice JPL is calling these ice blocks rather than 'rocks'). Now comes the fun part: we'll be getting details and more images all night long and unravelling the data will take months. What a story, and what a triumph for ESA, NASA and the Italian Space Agency!

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Huygens Data Flowing

Incoming data shows that Huygens' instruments were functioning nominally throughout the descent. From this morning's (EST) press conference, this statement by Jean-Jacques Dordain, ESA's Director General: "The morning was good; the afternoon is better. We were an engineering success this morning, but we can say this afternoon that we are also a scientific success. We are the first visitors to Titan, and scientific data that we are collecting now shall unveil the secrets of the new world. In fact we have got on the ground station data from Huygens long after the touchdown, more than two hours. I must say that we are short of ground stations! The batteries are much more solid than the number of ground stations which can receive the signal. Cassini has just started to deliver the data collected by Huygens, and we might be able to see the results during the night." And this fascinating detail from Emily Lakdawalla's weblog for the Planetary Society: One thing that may have helped the...

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Huygens on Titan

Huygens, now on the surface of Titan, has been transmitting data for five hours now, twice the expected time. Signals received by the Parkes Observatory in Australia first confirmed that the probe had survived the landing. It has also been confirmed that at least one experiment -- the Doppler Wind Experiment -- has been successful. Update: Cassini has turned toward Earth and is now transmitting Huygens data, with about forty minutes of preliminaries before the crucial science data are sent. ESA scientists should start looking at the first datasets around 1130 EST. The key question remains: how sound are the data? From John Noble Wilford's story on the New York Times Web site (free registration required): The possibility remains that a design flaw in Cassini's radio receiver system will hopelessly scramble the data. Engineers anticipated that signals from the wind-tossed Huygens would vary widely in frequency and strength, and thus compensated for it in the receiver's design. But they...

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Huygens Descending on Main Chute

The Green Bank radio telescope in West Virginia has picked up the Huygens carrier signal, which should have been activated after the opening of the main chute and the dropping of the heat shield. The signal carries no data other than this: Huygens made it through the entry into Titan's atmosphere. We should have data available by 1310 EST, routed from Huygens through Cassini. From an ESA press release: 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. Says...

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Weblog from Darmstadt Covers Huygens

The Planetary Society's Emily Lakdawalla is covering Huygens events from Darmstadt here. From her latest post: Another item that was news to me came from Marty Tomasko, the University of Arizona researcher who heads the Descent Imager Spectral Radiometer team (that's the main camera on Huygens). His last images are expected to come from about 150 meters off the ground. But, if Huygens survives the landing, DISR could still take pictures. What's cool about that is if Huygens lands in a liquid, it would be taking pictures through that liquid, seeing what's suspended in it. But I've been taking an informal poll of the science team to find out what they think they will land on, and no one has predicted liquid. The predictions range from "icy" to "squelchy" (the latter is how Surface Science Package investigator John Zarnecki described it ). After a few of these questions during the press briefing, Tomasko finally said, "This is probably not the best day to speculate. Probably you should...

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NASA TV Coverage Schedule for Huygens

Via the NASA TV site. Note the 2:45 PM slot, offering the first images from Titan (all times are EST). January 14, Friday 3 a.m. - 3:30 a.m. - Live Coverage and Commentary "Cassini Turns Towards Titan - Interruption of Radio Contact" - JPL/ESA 5 a.m. - 6:30 a.m. - Live Coverage and Commentary "The Huygens Probe Enters the Atmosphere of Titan" - JPL/ESA 6:30 a.m. - 7 a.m. - JPL Commentary - JPL (Mission Coverage) 7:30 a.m. - 8 a.m. - ESA News Briefing "Mission Status" - JPL/ESA 8:30 a.m. - 9:15 a.m. - ESA Commentary on Huygens Probe Mission - JPL/ESA (Mission Coverage) 9:30 a.m. - 10 a.m. - JPL Commentary - JPL (Mission Coverage) 10 a.m. - 10:30 a.m. - ESA Commentary "Cassini Turns Back to Earth - Data Transmission Begins" - JPL/ESA 10:30 a.m. - 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...

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JPL Huygens Schedule and Animations

The Jet Propulsion Laboratory has posted a Huygens arrival schedule showing 4:51 AM EST as the time when Huygens powers up its transmitters. Pilot chute deployment now estimated at 5:16 AM EST, and surface touchdown at 7:34 AM EST. Also available at this page are multimedia files of Huygens arriving and a tracking animation. Image: An artist's conception of hydrocarbon pools, icy and rocky terrain on the surface of Saturn's largest moon Titan. Image by Steven Hobbs (Brisbane, Queensland, Australia).

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Preparing for Huygens’ Descent

The European Space Agency offers an outstanding animation showing the stages of Huygens' descent to Titan's surface tomorrow. Also available is an animation of the view from Cassini during the Huygens' descent. Some interesting facts about the event: Huygens' atmospheric entry angle is a whopping 65° at a velocity of six kilometers per second, with touchdown planned for the daylight side in the southern hemisphere. The probe will pull 14g during deceleration. The thermal shield will slow the probe to 400 meters per second within three minutes. Next comes deployment of a 2.6-meter pilot chute at 160 kilometers altitude. Within seconds, the pilot chute will pull off the probe's aft cover; the main parachute (8.3 meters) will then deploy before the front shield is released. At 110 kilometers, the main chute will be jettisoned; a smaller, 3-meter chute will then be deployed. The DISR instrument (Descent Imager/Spectral Radiometer) will switch on its lamp for surface illumination and...

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Magnetic Field Helps Controllers Study Huygens Separation

ESA provides an interesting explanation of a question that had puzzled more than one reader: given that the Huygens probe provided no telemetry at the time, how did controllers know that its Christmas Eve separation from the Cassini orbiter had been nominal? It's true that Cassini was able to send data showing its own change in attitude due to the Huygens release, but how did we learn that Huygens was spinning at just the right rate (vital for a correct entry into Titan's atmosphere)? The answer: Huygens houses a weak magnetic field, despite attempts to render it 'magnetically clean' when it was constructed. The field is weak enough not to interfere with Cassini's sensitive instruments, but turns out to be measurable by its magnetometers. Cassini's Dual Technique Magnetometer (MAG) team used this data to establish the rate of Huygens' spin. From a news release from ESA: Professor Michele Dougherty, Principal Investigator for MAG, said, "What was observed by MAG just after the probe...

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JPL Releases Huygens Coverage Map

The Jet Propulsion Laboratory is offering this map of planned imaging coverage for the Huygens probe as it descends toward Titan's surface on Friday. 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 Descent Imager/Spectral Radiometer is one of two NASA instruments on the probe. The colored 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. Credit: NASA/JPL/Space Science Institute. Click here for further information on the map and background about the descent. We are less than two days away from Huygens' entry into Titan's atmosphere, and Centauri Dreams seconds the JPL intro to this image: Go Huygens!

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Probable Planet Circling a Brown Dwarf

The American Astronomical Society's 205th national meeting, in San Diego, California, ends tomorrow. And this meeting is special: the last attendance projection Centauri Dreams saw was 2500, with 1640 papers submitted, 180 scientific sessions, and 70 new Ph.D dissertations presented. All in all, we'll have material for months ahead coming out of AAS, and as always, we'll pay special attention to extrasolar planetary studies, with the occasional foray into the mind-boggling world of cosmology. Let's start with Hubble data that support the idea there is a planet orbiting a brown dwarf 225 light years away in the constellation Hydra. Last spring, the European Southern Observatory's Very Large Telescope reported on a possible planetary companion to the star, which has the mind-boggling designation 2MASSWJ 1207334-393254 (we prefer its nickname: 2M1207). The object in question is one-hundredth the brightness of the parent star, burning (according to this news release at the European...

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Charter

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For many years this site coordinated its efforts with the Tau Zero Foundation. It now serves as an independent forum for deep space news and ideas. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image courtesy of Marco Lorenzi).

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