DAWN mission to orbit 1 Ceres & 4 Vesta.

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3488

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Dawn arrives in Florida<br />NASA NEWS RELEASE<br />Posted: April 10, 2007<br /><br />The Dawn spacecraft arrived at Astrotech Space Operations in Titusville, Fla., at 9 a.m. EDT today. Dawn, NASA's mission into the heart of the asteroid belt, is at the facility for final processing and launch operations. Dawn's launch period opens June 30. <br /><br />"Dawn only has two more trips to make," said Dawn project manager Keyur Patel of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "One will be in mid-June when it makes the 15-mile journey from the processing facility to the launch pad. The second will be when Dawn rises to begin its eight-year, 3.2-billion-mile odyssey into the heart of the asteroid belt." <br /><br />The Dawn spacecraft will employ ion propulsion to explore two of the asteroid belt's most intriguing and dissimilar occupants: asteroid Vesta and the dwarf planet Ceres. <br /><br />Now that Dawn has arrived at Astrotech near NASA's Kennedy Space Center, final prelaunch processing will begin. Technicians will install the spacecraft's batteries, check out the control thrusters and test the spacecraft's instruments. In late April, Dawn's large solar arrays will be attached and then deployed for testing. In early May, a compatibility test will be performed with the Deep Space Network used for tracking and communications. Dawn will then be loaded with fuel to be used for spacecraft control during the mission. Finally, in mid-May, the spacecraft will undergo spin-balance testing. Dawn will then be mated to the upper stage booster and installed into a spacecraft transportation canister for the trip to Cape Canaveral Air Force Station. This is currently scheduled for June 19, when it will be mated to the Delta II rocket at Pad 17-B. <br /><br />The rocket that will launch Dawn is a Delta II 7925-H manufactured by the United Launch Alliance; it is a heavier-lift model of the standard Delta II that uses larger solid rocket boosters. The first stage is scheduled to be er <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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holmec

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Dust and rocks <img src="/images/icons/laugh.gif" /> <br /><br />It would be sweet if they find water and methane.<br />But I bet one ore is out there....olivine. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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3488

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Very funny holmec!!! In the case of 1 Ceres, probably a lot of ice too.<br /><br />Below is a nice six image colour image panel from HST of 1 Ceres.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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3488

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Image & shape profile of 4 Vesta from the Hubble Space Telescope.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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3488

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1 Ceres as seen through one rotation using adaptive optics, Keck.<br /><br />1 Ceres can be seen to have craters, some with central peaks & smoother plains.<br /><br />With thanks to Jon Clarke for this image.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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qso1

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Looks more planetlike than asteroid like because in addition to roundness, there appears to be a more varied surface. Coloration and high albedo in some places. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>
 
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3488

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I would not be surprised if both or one or the other of 1 Ceres & 4 Vesta have at least one small moon. If a medium sized asteroid like 243 Ida can hold on to one (Dactyl), I would expect 1 Ceres or 4 Vesta to be able to hold on to any moons. I hope the 2 Pallas encounter can happen also.<br /><br />Hi qso1. Yes, 1 Ceres does appear to have differentiated into a core, ice rich mantle & a hardened carbon rich crust. <br /><br />1 Ceres appears to be more evolved than the giant, planet sized Jupiter moon Callisto!!!!<br /><br />The surface thus far, does not appear to be homogenous as you have stated. 1 Ceres is certainly an interesting object.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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3488

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Dawn Arrives in Florida—A Little After Dawn<br /><br />April 10, 2007—The Dawn spacecraft arrived at Astrotech Space Operations in Titusville, Fla., at 9 a.m. EDT today. Dawn, NASA’s mission into the heart of the asteroid belt, is at the facility for final processing and launch operations. Dawn’s launch period opens <br />June 30. <br /><br />"Dawn only has two more trips to make," said Dawn project manager Keyur Patel of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. "One will be in mid-June when it makes the 15-mile journey from the processing facility to the launch pad. The second will be when Dawn rises to begin its eight-year, 3.2-billion-mile odyssey into the heart of the asteroid belt." <br /><br />Dawn Arrives in Florida - A Little After Dawn <br /><br />NEWS RELEASE: 2007-038 April 10, 2007<br /><br />The Dawn spacecraft arrived at Astrotech Space Operations in Titusville, Fla., at 9 a.m. EDT today. Dawn, NASA’s mission into the heart of the asteroid belt, is at the facility for final processing and launch operations. Dawn’s launch period opens June 30. <br /><br />"Dawn only has two more trips to make," said Dawn project manager Keyur Patel of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. "One will be in mid-June when it makes the 15-mile journey from the processing facility to the launch pad. The second will be when Dawn rises to begin its eight-year, 3.2-billion-mile odyssey into the heart of the asteroid belt."<br /><br />The Dawn spacecraft will employ ion propulsion to explore two of the asteroid belt's most intriguing and dissimilar occupants: asteroid Vesta and the dwarf planet Ceres.<br /><br />Now that Dawn has arrived at Astrotech near NASA’s Kennedy Space Center, final prelaunch processing will begin. Technicians will install the spacecraft’s batteries, check out the control thrusters and test the spacecraft’s instruments. In late April, Dawn’s large solar arrays will be a <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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MeteorWayne

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Latest update:<br /><br />EXPENDABLE LAUNCH VEHICLE STATUS REPORT<br /><br />Mission: Dawn <br />Launch Pad: Cape Canaveral Air Force Station, Fla. <br />Launch Vehicle: Delta II 7925-H <br />Launch Date: NET June 30, 2007 <br />Launch Time: 15:13:15 p.m. EDT <br />Comprehensive spacecraft system performance testing continues. <br />Instrument final alignment is under way.<br />A test of the spacecraft's primary communications antenna is scheduled <br />for May 21.<br />The spacecraft solar arrays will be attached and deployed May 21 - 24.<br />No spacecraft issues or concerns have arisen during testing to date.<br />Previous status reports are available on the Web at:<br /><br />http://www.nasa.gov/centers/kennedy/launchingrockets/status/2007 <br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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3488

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Thank you very much MeteorWayne.<br /><br />This is truly good news. <img src="/images/icons/laugh.gif" /><br /><br />No problems at all to report. <br /><br />Launch three days after our 'esteemed' Prime Minister quits!!!!!!!!<br /><br />In all seriousness, this is an important mission.<br /><br />I was part of the campaign to get DAWN reinstated after the initial cancellation, so thank <br />you MeteorWayne for being the bearer of such good news & having the respect & consideration of helping<br /> to keep me informed. <br /><br />The Delta II is a great launcher & I have a lot of faith in it launching both<br /> DAWN & Mars Phoenix Lander without any problems.<br /><br />So soon ,1 Ceres & 4 Vesta, HERE WE COME. It is your turn to give up your secrets!!!!!<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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3488

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From DAWN website.<br /><br />April 15 , 2007<br /><br />Dear Dawnthecoasts, <br /><br />The Dawn spacecraft has completed its longest terrestrial journey on its path to asteroid Vesta and dwarf planet Ceres. While it will be propelled by exotic ion propulsion during most of its mission, this segment of its travels was accomplished using decidedly more conventional chemical propulsion. After being packed with great care at the Naval Research Laboratory (NRL) in Washington, DC, the spacecraft and a great deal of additional equipment left on a truck a few hours before dusk on April 9. Less than 18 hours later, a few hours after dawn, it arrived at its home for the next two months, Astrotech Space Operations in Titusville, Florida, near Cape Canaveral.<br /><br />When last we checked in with the spacecraft, it had completed an extensive series of tests in a thermal vacuum chamber at NRL. The pace of activities has not let up since then, with engineers and technicians rarely letting the spacecraft have a rest. Myriad tasks are being completed and checked off the long and carefully planned list of steps necessary before the probe may begin its ambitious mission in harsh and remote parts of the solar system. For example, thorough checks for any possible leaks in the ion propulsion system and the reaction control system (the system that uses small conventional thrusters to aid in orienting the spacecraft in the zero-gravity of spaceflight) verified their integrity, certifying them for many years of operation in space. More tests have been conducted to confirm the flow of information between the many elements of the mission control systems and all of the computers onboard the spacecraft. <br /><br />As expected, some of the thermal vacuum tests had revealed the need to make some minor changes in a few of the 9000 wires connecting different elements of the spacecraft. As these updates were in progress, the device that controls the high voltage, high power electricity from Dawn's larg <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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MeteorWayne

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Thanx Andrew, great update.<br /><br />Pop quiz.....<br /><br />Who knows which asteroid is #3? <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
3

3488

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I do, but will not answer straight away, a poser for a newbie perhaps??<br /><br />I will give a clue. It has only FOUR letters, tow consonants<br />& two vowels & is the name of the highest<br /> goddess of the Romans.<br /><br />Despite being number 3, this asteroid is considerably smaller than the three mentioned above. <br /><br />In fact it does not make the top ten in size, in fact number 13 in size order.<br /><br />This asteroid has an unsusually reflective surface (albedo 28%) density of about 3.4 gm3 (one of the densest asteroids), <br />axial tilt 51 deg, rotates once every eight hours & has a large 100 km wide impact crater.<br /><br />I have posted below some AO images of said asteroid.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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MeteorWayne

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#13 in size (of the asteroid belt asteroids) ~ 247 km diameter. <br /><br />About the 182nd largest object orbiting the sun (not including moons) <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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And there's a clue in a thread very nearby if you know what Io mean <img src="/images/icons/wink.gif" /> <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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3488

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There is a good clue there indeed MeteorWayne.<br /><br />Also in the UK school children of age 7 to 11 attend JUNIOR school (provided they are not bunking off) <br />& yes of course not long till JUNE!!!!!!!<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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h2ouniverse

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Dear all,<br /><br />Mission Dawn looks very exciting. Especially for Ceres. A pity we will have to wait for 2015 to see what the closest "dwarf planet" looks like. With New Horizons arriving at Pluto and Charon in 2015, this year they will play Ice White and the Three Dwarves...<br />The ideal scenario would be that Dawn spots points of past resurgence of liquid water (including as Andrew 3488 suggests outlets of ancient cryovolcanoes). Would make ideal landing sites for exobiobots, closer than Europa, and not at the bottom of a double gravity well [mission to Jupiter's or Satrun's icy moons are so hellish from that point of view, two large delta-Vs to do and no atmosphere for braking like for Huygens]<br /> Best regards<br />Joel
 
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PistolPete

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Ice is one thing, but you also need heat. Jupiter's gravity kneads Europa's core like dough which is the source of its theorized geothermal heating and possible liquid water ocean. Just having water ice isn't enough for life to form. Comets have plenty of ice, but I doubt you would find much life in the Kuiper Belt or the Oort Cloud. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>
 
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h2ouniverse

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PistolPete,<br /><br />First Ceres is in the asteroid belt, so at a shooting distance from Mars or Earth potentially bacteria-loaded meteorites. Second it seems that microbial life developped very fast on Earth as soon as liquid water was there (few millions years). For Ceres to be differentiated, it had to be strongly heated (energy due to violent accretion process, quite common it seems). Granted, it should now be frozen since billions of years. But it must have passed through a period with pockets of liquid water around its smoldering rocky core, covered by a less-and-less thin iceshelf (as Enceladus is now). Cryovolcanism may (might) then have occurrred bringing water locally to surface, at identifiable spots, not too much covered by regolith and debris (to be seen). When I mentionned exobio-robots, I was thinking about detecting spores or traces conserved in ice at such hypothetical places.<br /><br />By the way, for Kuiper belt, please note that:<br />* Triton, a TNO captured by Neptune, shows cryovolcanism, although no other large moon exists around Neptune to destabilize its tidal-locking<br />* 2003EL61 [about 2000km x 1500 km x 1000 km TBC] has a very fast rotation (every 4h) and elongated shape, and two moons, and many similar-orbit colleagues suggesting it results from massive impact. The centrifugal force is such that this ice-covered rocky object (density 2.6) is subjected to huge deformation. Depending on how long ago the potential impact occurred, you might or not have still a hot core, and pockets of water...<br />* Many Kuiper belt objects are multiple, paving the way for tidal effects<br />* Many Kuiper belt objects are still to be discovered (4 large ones announced just since 2005)<br />* An Earth-sized or Mars-sized object is not ruled out beyond say, 200AU (visible light received is roughly a function of the fourth power of distance to Sun, meaning even large bodies would have magnitudes beyond 20 and might have escaped detection; Such an object, even
 
P

PistolPete

Guest
Water, especially water in frozen form does not necessitate life. Life not only needs water, but energy as well as chemicals to react with the water. The reason that Europa is such an exciting prospect for life is because it has all three of these things. Ceres probably has a layer of frozen water, but it is buried underneath the regolith and is deprived of the energy of the Sun. Even if the ice were on the surface, radiation from the Sun as well as cosmic radiation would make life hard for anything except extremophiles.<br /><br />Water cannot exist on the surface, however. Not even in ice form. This is because Ceres is inside the Frost Line. The Frost Line is a line approximately 4 AU from the Sun where, inside of it, water cannot exist in a solid state by itself. Outside this line water can exist in ice form. The ice therefore has to remain buried deep beneath the surface, far away from the energy of the Sun.<br /><br />By themselves, planetesimals are usually too small to retain their heat from the accretion at the beginning of the Solar System. Triton's cryovolcanism is produced by the same geothermal mechanism as is found on Europa and is not hindered by being tidally locked (all of the four Galilean moons are tidally locked). Triton's orbit is elliptical (just like every other orbiting body in the Universe). When Triton gets close to Neptune, Neptune's gravity will pull on the inner side more than the outer side, causing the core to stretch. As Triton moves farther away from Neptune, its gravitational grip lessens releasing the core and allowing it to contract. This pulling and contracting causes the geothermal heating which produces cryovolcanism on Triton. This kind of geothermal heating can only be caused by large gravity fields acting on much smaller one. Volcanism cannot exist on the Moon because the Earth's gravity field isn't strong enough to pull on its core, the same goes for the Mars-Phobos-Deimos system as well.<br /><br />I'm not saying <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>
 
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h2ouniverse

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Peter, <br />About Ceres:<br />I am refering to past liquid water on Ceres, not current living organisms. The Frost line was not there at the beginnging of Solar System (cooler Sun). The strucure envisaged for Ceres is as per picture attached.<br />Clear spots identified by Hubble suggest that recent impact craters may have cleared the regolith and uncovered the ice shell. So potentially ancient cryo-activity features...<br />We know that bio-material is particularly resilient (see article linked)<br />http://www.space.com/scienceastronomy/antarctic_life_021216.html<br />Again I am not suggesting finding living or revivable organisms, but fossil or frozen dead bacteria.<br />By the way some slow-metabolism, eon-lifespanned bacteria have been discovered on Earth in ice at -40°C.<br /><br />In a more general way, water liquid over few millions years + hydrocarbons seem enough for bacteria to prosper. This is what Earth's history tells.<br /><br />If Dawn shows accessible cryo-features, I still strongly believe they would constitute a primary exobio target, for they would be easier to explore (and sample-analyze) with a robot than Europa. <br /><br />Regards.
 
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h2ouniverse

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Peter<br />About planetesimals in general:<br />There are at least five known mechanisms for internal heat generation:<br />1) release by collapsing after accretion<br />2) radioactive elements decay<br />3) impact of large bodies<br />4) tidal effects (either due to multiple systems or as you mentioned, highly elliptical orbits).(*)<br />5) changes in spin<br /><br />May be there are other ones, for the recent trend is to revise upward the assessment of internal heat of many bodies. Including Mercury by the way! (with this assumption about effect of Sulphur).<br />Also it seems that tidal energy has been underestimated in the past (Enceladus, Dione, Titan).<br /><br />All these mechanisms apply to planetesimals. Granted, they cool down very fast. But it does not seem that a long time for liquid water persistance is required for basic life to thrive before the brand-new exoecosystem freezes.<br /><br />I am eager to see too views of Pluto+Charon, both tidally-locked to each other and relatively close.<br /><br />(*) you misunderstood me or I poorly expressed myself: I meant that tidal locking favors indeed generation of heat, provided that a perturbation tends to destabilize the locking to the primary: influence from other moons in the case of Jovian, Saturnian or Uranian moons, or as you point out, effect of high orbit eccentricity for Triton [Note too that this effect has been suspected for the early Moon, that might have had a very elliptical orbit at the beginning]. <br /><br />Regards,<br />Joel
 
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MeteorWayne

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The latest (as of 5/18)<br />Mission: Dawn <br />Location: Astrotech Space Operations Facility <br />Launch Pad: 17-B <br />Launch Vehicle: Delta II 7925-H <br />Launch Date: Target June 30, 2007 <br />Launch Window: 5:13:15 p.m. EDT <br /><br />Preparations are under way for moving the Dawn spacecraft to an <br />adjacent clean room high bay for solar array integration. <br /><br />Next week, the two spacecraft solar arrays, each consisting of four <br />panels, will be attached to the Dawn spacecraft and undergo <br />deployment testing. A solar array lighting test also will be <br />performed before the arrays are stowed for flight. This activity is <br />scheduled for May 21-24. <br /><br />The spacecraft will be moved to Astrotech's Hazardous Processing <br />Facility for fueling on May 26. <br /><br />The Delta II first stage will be hoisted into the launcher at Pad 17-B <br />on May 23 and attachment of the nine solid rocket boosters will <br />begin.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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3488

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Thank you very much MeteorWayne.<br /><br />If I see anything new, I will post it on this thread.<br /><br />Please Boeing & Delta launch control<br /><br />DON'T screw this up!!!!!!!!!!! <img src="/images/icons/frown.gif" /><br /><br />As you can see, I am very nervous, but have a lot of faith in the Delta II. <br /><br />A brilliant reliable launcher.<br /><br />This mission MUST succeed!!!!<br /><br />Thank you too to H20universe for your informative posts.<br /><br />If it is proven that 1 Ceres contains as much subsurface ice, as is thought,<br />then 1 Ceres will have more fresh water (abeit frozen) than all of the Earth's oceans put together.<br /><br />I would expect 1 Ceres to have shown signs of cryovolcanism, but how much, remains <br />to be seen, I do not know. Subsequent cratering may have destroyed much evidence.<br /><br />Jon Clarke was kind enough to post me some images a while back, showing 1 Ceres<br />with AO from the Keck. There where clear indications of smoother plains<br />& large, but very shallow craters. The fracturing & faulting suspected was not seen (the resolution was not enough<br />to bring out such features), but will see when DAWN arrives.<br /><br />1 Ceres will not be a bore.<br /><br />Thank you too to PistolPete for your informative posts too.<br /><br />Yes, you are correct. The maximum surface temerature on 1 Ceres, is a toasty minus 34 Celsius. Whilst<br /> in itself, that is well, below freezing point of fresh water<br />in an exposed vacuum, ice will sublime at that temperature.<br /><br />Regarding the Frost Line. It is well worth remembering that the Sun<br />is considerably more powerful now, than in its youth.<br /><br />Assuming 1 Ceres is in much the same Heliocentric orbit now, as back then,<br />1 Ceres would have been well beyond the frost line, in the Sun's youth.<br /><br />1 Ceres, is covered in frozen dust & regolith & this will keep subsurface ice frozen.<br /><br />As H20universe says, fresh impacts will excavate ice, but over time <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
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