Author
|
Topic: Looming out of the darkness
|
|
|
|
Jimmy Brogan
rabble-rouser
Babbler # 3290
|
posted 18 May 2004 03:16 AM
quote: As Cassini nears its rendezvous with Saturn, new detail in the banded clouds of the planet's atmosphere are becoming visible. Cassini began the journey to the ringed world of Saturn nearly seven years ago and is now less than two months away from orbit insertion on June 30. Cassini?s narrow-angle camera took this image on April 16, 2004, when the spacecraft was 38.5 million kilometers (23.9 million miles) from Saturn. Dark regions are generally areas free of high clouds, and bright areas are places with high, thick clouds which shield the view of the darker areas below. A dark spot is visible at the south pole, which is remarkable to scientists because it is so small and centered. The spot could be affected by Saturn's magnetic field, which is nearly aligned with the planet's rotation axis, unlike the magnetic fields of Jupiter and Earth. From south to north, other notable features are the two white spots just above the dark spot toward the right, and the large dark oblong-shaped feature that extends across the middle. The darker band beneath the oblong-shaped feature has begun to show a lacy pattern of lighter-colored, high altitude clouds, indicative of turbulent atmospheric conditions. The cloud bands move at different speeds, and their irregularities may be due to either the different motions between them or to disturbances below the visible cloud layer. Such disturbances might be powered by the planet's internal heat; Saturn radiates more energy than it receives from the Sun.
From: The right choice - Iggy Thumbscrews for Liberal leader | Registered: Nov 2002
| IP: Logged
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Albireo
rabble-rouser
Babbler # 3052
|
posted 13 January 2005 06:15 PM
Tonight 's the night... quote: The Huygens space probe will begin the most important stage of its seven-year journey when it hits Titan's atmosphere at about 9:00 GMT on Friday 14 January.The probe was carried to Saturn by the Cassini spacecraft, which released Huygens on 25 December 2004. Huygens has lain dormant for the past 20 days as it cruised towards Titan at about 21,000 kilometres per hour. When it flies through Titan's thick clouds the probe will determine the composition of the atmosphere, measure the wind speed and take about 750 pictures, along with a range of other scientific readings. All will be relayed to the Cassini mother ship, and then sent to Earth. Titan is the only moon in our Solar System with a significant atmosphere, and scientists believe that it may be likened to a colder version of an early Earth. But the hydrocarbon smog around Titan has concealed what lies on the surface, so if Huygens survives its trip it may also find seas of liquid ethane, thick tar or icy rock on the -180 °C moon.
The Space.com coverage has a link to Nasa TV, where you can watch a live webcast, starting at 12am Pacific, 3am Eastern, or 4am babble time. [ 13 January 2005: Message edited by: Albireo ]
From: --> . <-- | Registered: Sep 2002
| IP: Logged
|
|
|
|
Albireo
rabble-rouser
Babbler # 3052
|
posted 14 January 2005 11:53 AM
And, apparently, touchdown! quote: A signal from the craft picked up by Earth-based radio telescopes during the descent continued hours after the landing was supposed to have taken place, indicating that Huygens was safely on the surface.Scientists believe it touched down on land rather than splashed into a lake or sea of liquid hydro-carbons. But they will not know until later today if the probe’s instruments are working properly, when confirmation of the landing is relayed to the European Space Agency Operations Control Centre (Esoc) in Darmstadt, Germany, at about 4pm. The first black and white images from Titan are not due to arrive until later this evening.
[Note: Scottish source, so "4pm" should be already, and "this evening" is within a few hours.][ 14 January 2005: Message edited by: Albireo ]
From: --> . <-- | Registered: Sep 2002
| IP: Logged
|
|
aRoused
rabble-rouser
Babbler # 1962
|
posted 14 January 2005 12:14 PM
ESA website currently says 1615 UTC for touchdown, ie right as I'm writing this, and then of course there's the time for the signal to travel back here, so we've got a few hours to wait.Hee, I'm so excited, and I just can't fight it. Edit: link The Scotsman seems to have confused 'received carrier signal' with 'touchdown'. landing timeline So if it all worked, the signal's being sent right nowish. [ 14 January 2005: Message edited by: aRoused ]
From: The King's Royal Burgh of Eoforwich | Registered: Dec 2001
| IP: Logged
|
|
|
Albireo
rabble-rouser
Babbler # 3052
|
posted 14 January 2005 01:36 PM
OK, well, now they say it's for real: quote: 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. ...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.
From: --> . <-- | Registered: Sep 2002
| IP: Logged
|
|
|
|
|
|
|
Jimmy Brogan
rabble-rouser
Babbler # 3290
|
posted 15 January 2005 02:26 AM
quote: This is one of the first raw images returned by the ESA Huygens probe during its successful descent. It was taken from an altitude of 16.2 kilometres with a resolution of approximately 40 metres per pixel. It apparently shows short, stubby drainage channels leading to a shoreline. It was taken with the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe.
This Descent Imager/Spectral Radiometer sounds like it could produce some terrific data: quote: The Descent Imager/Spectral Radiometer (DISR) is the optical instrument that makes measurements at solar wavelengths aboard the Huygens Probe of the Cassini mission. This instrument is being developed in a collaborative effort by scientists from the US, France, and Germany. DISR measures solar radiation using silicon photodiodes, a two-dimensional silicon Charge Coupled Device (CCD) detector and two InGaAs near-infrared linear array detectors. The light is brought to the detectors using fibre optics from many separate sets of foreoptics that collect light from different directions and in different spectral regions. In this way the instrument can make a suite of measurements which are carefully selected to answer key questions concerning the nature of the surface and the composition, meteorology, thermal balance, and clouds and aerosols in the atmosphere of Titan.
Geektacular!!!! [ 15 January 2005: Message edited by: JimmyBrogan ]
From: The right choice - Iggy Thumbscrews for Liberal leader | Registered: Nov 2002
| IP: Logged
|
|
|
Jimmy Brogan
rabble-rouser
Babbler # 3290
|
posted 22 January 2005 12:22 AM
Probe finds inflammable methane rain lashes Titan's moon quote: PARIS - The European probe that landed on Titan has found that liquid methane rain lashes Saturn's largest moon, a freezing, primitive but active world of ridges, peaks, river beds and deserts scoured by the same forces of erosion as on Earth, scientists said today.Methane is a highly flammable gas on Earth, but on Titan it is liquid because of the intense pressure and cold. "There is liquid that is flowing on the surface of Titan. It is not water ? it is much too cold ? it's liquid methane, and this methane really plays the same big role on Titan as water does on Earth," mission manager Jean-Pierre Lebreton told a news conference.
quote: But unlike Earth, where water constantly circulates back into the atmosphere, Titan's methane never evaporates back into airborne smog."There must be some source of methane inside Titan which is releasing the gas into the atmosphere. It has to be continually renewed, otherwise it would have all disappeared," said Owen.
Could there be biology that's replacing the methane?
From: The right choice - Iggy Thumbscrews for Liberal leader | Registered: Nov 2002
| IP: Logged
|
|
|
|
Willowdale Wizard
rabble-rouser
Babbler # 3674
|
posted 09 February 2005 06:45 PM
perhaps not as sexy as titan, but saturn's got a pretty hot ass. quote: Saturn represents the first case of a warm polar cap ever detected in the Solar System. Saturn's southern pole should be warmer currently because it has been exposed to 15 years of continuous sunlight, having just reached its summer Solstice late in 2002. But the discrete boundaries where temperatures suddenly jump are a surprise for scientists. The tropospheric temperature increases toward the pole abruptly near 70 degrees latitude from 88 to 89 Kelvin (-185 to -184 Celsius) and then to 91K (-182C) right at the pole. Near 70 degrees latitude, the stratospheric temperature increases even more abruptly from 146 to 150K (-127 to -123C) and then again to 151K (-122C) right at the pole.
From: england (hometown of toronto) | Registered: Jan 2003
| IP: Logged
|
|
|
|
Jimmy Brogan
rabble-rouser
Babbler # 3290
|
posted 12 September 2005 06:09 PM
Earth and Saturn's moon Titan show striking similarities because both occupy "sweet spots" in our Solar System quote: The researcher then turned to three bodies in the outer Solar System: Ganymede, Titan and Triton. The chemistry is different, but similar principles apply. Jupiter's moon Ganymede, the closest of the three to the Sun, is similar in size to Titan, but lacks the methane and nitrogen that drive liquid processes on the saturnian moon: "It's a kind of baked out version of Titan," said Lunine. Neptune's moon Triton, much further from the Sun than both Ganymede and Titan, possesses methane and nitrogen. But its small size caused them to freeze, ending any prospect of geological activity. Scientists have been revealing new details about Titan at the meeting in Cambridge. Ralph Lorenz of the University of Arizona, said that the river channels and flows on Titan are fashioned by "monsoon" events. 'Catastrophic rains' It takes a relatively long time for methane to build up to a point where it can rain down on Titan's surface. Scientists, therefore, think rains are only occasional, but catastrophic, when they occur. Evidence also suggests Titan is constantly being resurfaced by a fluid mixture of water and ammonia spewed out by volcanoes and hot springs, explaining why Titan is not littered with impact craters like its neighbours
From: The right choice - Iggy Thumbscrews for Liberal leader | Registered: Nov 2002
| IP: Logged
|
|
Jimmy Brogan
rabble-rouser
Babbler # 3290
|
posted 01 December 2005 08:41 PM
Huygens team releases final report quote: Huygens' findings "really reveal an extraordinary world resembling Earth," said scientist Jean-Pierre Lebreton. "But there are differences," he added. The natural, chemical processes responsible for the origins of life on Earth likely froze on Titan, said scientist Francois Raulin of the University of Paris. "This bold initiative has proved brilliantly successful," said planetary scientist Tobias Owen of the University of Hawaii in Honolulu, in a commentary accompanying the papers in Nature. But a number of mysteries about Titan remain for scientists: • Chemical analysis shows that methane must be replenished on Titan every 10 to 20 million years, likely through volcanic eruptions. But no eruptions have been observed. An ocean of liquid methane may hide under the moon's crust. • A "mysterious component" that scientists couldn't recreate in the lab is mixed with icy surface materials on the moon, said scientist Bruno Bezard. • The probe spun the wrong way, clockwise, as it landed, for still-unknown reasons.
Pack a sweater.
From: The right choice - Iggy Thumbscrews for Liberal leader | Registered: Nov 2002
| IP: Logged
|
|
Albireo
rabble-rouser
Babbler # 3052
|
posted 09 March 2006 05:04 PM
Bump.Water discovered on Saturnian moon? Now Cassini has taken images of Saturn's moon Enceladus that may indicate a sea of liquid water under ice: quote: The surprising discovery, made by the Cassini spacecraft, shows evidence of liquid water reservoirs that erupt from geysers (natural hot-springs) on Saturn's moon Enceladus."High-resolution Cassini images show icy jets and towering plumes ejecting large quantities of particles at high speed," a NASA press release stated Thursday. Carolyn Porco, Cassini's imaging team leader said Thursday that the discovery was a "smoking gun" that proved water existed on the planet. "We realize that this is a radical conclusion – that we may have evidence for liquid water within a body so small and so cold," Porco said. "However, if we are right, we have significantly broadened the diversity of solar system environments where we might possibly have conditions suitable for living organisms."
(Image from NASA via USA Today.)
[ 09 March 2006: Message edited by: Albireo ]
From: --> . <-- | Registered: Sep 2002
| IP: Logged
|
|
|
|
|