Let's talk about Ceres

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mithridates

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There's still precious little information on Ceres even on Wikipedia, and that means that a lot of the information there is lacking. A lot of people here have been discussing Ceres with quite a bit of interest lately so I'll throw up a few items for discussion that have been on my mind.<br /><br />-Will the Large Binocular Telescope be taking any images of Ceres any time soon? If it's to be as good a telescope as it's supposed to be, I would be most interested in first seeing images of bodies that we have the worst images for at present - Pluto, Eris, Ceres, Vesta, etc.<br /><br />-Surface area is only 1.8 million square kilometres compared to 144 798 465 for Mars, 38 million for the Moon and 510 million for Earth. There seem to be some indications of an atmosphere, but very faint. I read somewhere that Ceres has about half the mass it would need to retain a proper atmosphere, is this correct? Even so, it usually takes thousands of years for a planet to lose an atmosphere and that wouldn't be a problem in the short term for colonization. Would using all the available water there be a good idea, and what kind of climate could be created at that distance? One day is about 10 hours.<br /><br />-Any other thoughts or predictions? <div class="Discussion_UserSignature"> <p>----- </p><p>http://mithridates.blogspot.com</p> </div>
 
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3488

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Hi there.<br /><br />1 Ceres does have a tenous gas envelope, prabably too thin to be called an 'atmosphere' as such. It will have the density of a good laboratory vacuum. The surface gravity of 1 Ceres is thought to be about 0.75% of Earth's.<br /><br />Assuming the measured density of 2.1g cm3 is correct, then 1 Ceres is about two thirds rock & one third ice in compostion. Observations suggest that 1 Ceres has differentiated into a silicate rich core & a thick ice mantle & a crust of ice, frozen in dust & frozen clays.<br /><br />The maximum temperature appears to be a very high minus 34 Celsius (239 Kelvin) in places. At the poles it is more like minus 220 Celsius (only 53 Kelvin). <br /><br />1 Ceres has an equatorial diameter of about 949 kilometres (589 miles). <br /><br />The Moon has a diameter of 3,480 kilometres (2,163 miles), Jupiter's volcanic moon Io has a diameter of 3,633 kilometres (2,258 miles), so 1 Ceres is roughly 30% of these two in size, so 1 Ceres is quite large. <br /><br />1 Ceres rotates on its axis in about 9 Hours & 8 minutes in a prograde (west to east like the Earth, Sun rises in the east, etc), the axial tilt is 6 degrees, so there are seasons, but not very pronounced as on Earth & Mars (the Sun would vary in altitude by 12 degrees during the Ceres year, & the Ceres Arctic & Antarctic circles would be at 84 Degrees North & South respectively).<br /><br />On 1 Ceres the North polar star 54 Draconis, South polar star Alpha Pictoris.<br /><br />The sunlight is about 11% of Earth's as 1 Ceres orbits about 2.75 AU from the Sun, once every 4 years & 219 days.<br /><br />Adaptive optic images show plains & craters with central peaks. The HST show a surface which is dark red & at least one bright spot, most likely a fairly 'recent' impact crater with an ejecta blanket making rays. There could also be extinct cryovolcanoes (erupt slushy ice, not molten rock).<br /><br />1 Ceres has been found so far to be moonless, <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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spacester

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Ceres is fascinating and I gotta believe a key to the science of solar system formation.<br /><br />I'm a guy who wants to commercially exploit the asteroids as soon as possible, sooner than most think is possible even. I've been contemplating the minor planets for 5+ years now.<br /><br />So I'm posting here just for the record and to encourage you to continue talking about this fascinating chunk of the solar system.<br /><br />IMO Ceres should be off limits to any and all private exploitation and should be the subject of the very most careful and complete exploration we can muster. When I talk about exploiting asteroids, it's about the Near Earth Objects (NEO), not the main belt asteroids. Even if that dictum changed, Ceres should still be strictly off limits until the scientists have had their fill. The reason is simple: there's only one Ceres but there's lots of asteroids.<br /><br />That atmosphere might turn out to be very interesting . . . and if the thing has much water as expected . . . it's a tempting target for water extraction, but in due time. <div class="Discussion_UserSignature"> </div>
 
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nexium

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My guess is double the mass of Ceres would not retain an atmosphere more than a few centuries. Ceres receives more solar radiation than any of the moons of the gas giant planets, yet these moons are generally airless, except the moons with over 100 times more mass than Ceres.<br />My guess is the mass center of Ceres is the best place for a large colony. A spherical cavern, with a radius of one kilometer would have a volume of 4/3 3.14 = 4.19 cubic kilometers = 4,190,000,000 cubic meters which would be spacious accomodations for 100 million humans. Food would need to be produced by nano technology as conventional greenhouse agriculture on the surface would produce less than 1% of the needed food, even with the help of giant mirrors to provide more sunlight for photosynthesis. Neil
 
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mithridates

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I don't mind an atmosphere that can retain itself for a few centuries, that's a lot of time from our point of view. What would be the warmest climate that could be created on the planet if we were able to create one, and how much would need to be produced before we have an atmosphere as thick as the one on Mars for example? Though farther away, having a surface area of only a bit more than 1% of that of Mars would make planetwide changes much easier.<br /><br />In another thread on the atmosphere of the Moon a few people were suggesting using a heavy gas (SF6?) for most of it, something that doesn't get knocked into space by the solar wind so easily, and then only a fraction would need to be gases we would need to sustain plant and other life. The first gas would be used for atmospheric pressure and modifying the climate. <div class="Discussion_UserSignature"> <p>----- </p><p>http://mithridates.blogspot.com</p> </div>
 
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mithridates

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I don't suppose anybody knows when we are due to get new data on Ceres, that is before the Dawn mission gets underway? I'd like to know when we can start to expect more details on the tenuous atmosphere it's supposed to have. <div class="Discussion_UserSignature"> <p>----- </p><p>http://mithridates.blogspot.com</p> </div>
 
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Boris_Badenov

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<font color="yellow"> I don't suppose anybody knows when we are due to get new data on Ceres, that is before the Dawn mission gets underway? </font><br /><br /> Check out this thread.<br /><br />http://uplink.space.com/showflat.php?Cat=&Board=missions&Number=548626&page=1&view=collapsed&sb=5&o=0&fpart= <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>
 
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spacester

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". . . using a heavy gas (SF6?) . . ."<br /><br />Um yeah I never spoke up on that one, but um, F as in Florine, right? How a terraforming project starts with one of the nastiest gases one can think of is beyond me. Chlorine is mild next to Florine, right?<br /><br />My point earlier on the science of Ceres is that the atmosphere needs to be very carefully measured and characterized before we go about altering it in any way.<br /><br />Having made that point again, it is very tempting to let myself start talking about the development possibilities <img src="/images/icons/laugh.gif" /> but I'm assuming this is the wrong thread, if not the wrong forum.<br /><br />I wonder what the center temperature is estimated to be? I do not recall . . . anyone? <div class="Discussion_UserSignature"> </div>
 
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3488

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I would not know, but given the 'relatively' small size of 1 Ceres & the fact that 1 Ceres does not appear to be under any undue tidal stress (unlike Io & Enceladus), 1 Ceres is likely to have cooled & solidifed throughout. I also doubt that 1 Ceres would have a huge amount of radioactive materials decaying to produce much internal heat now either.<br /><br />It does not rule out geological activity in the past, in fact I would expect the DAWN spacecraft to image evidence of previous activity such as extinct cryovolcanoes & cryovolcanic ice flows, unless subsequent impact cratering has destroyed it all.<br /><br />I now think that 1 Ceres is inactive & cold throughout, but that could be wrong.<br /><br />Perhaps sunlight could be triggering geysers, much like those on the Neptune moon Triton!! These could be maintaining an extremely tenous 'atmosphere' around 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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spacester

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mmmmmmm . . . cryovolcanic ice flows . . . . mmm . . . i love it when you talk dirty like that . . . ice geysers! . . . oh yeah, nice . . . keep talking . . . <br /><br /><img src="/images/icons/laugh.gif" /><br /><br />Sorry. But seriously: wouldn't that be sensational! That would have the potential to generate a lot of public excitement IMO.<br /> <div class="Discussion_UserSignature"> </div>
 
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Boris_Badenov

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I think it was Shuttle_Guy that said 1 Ceres is too close to the Sun to maintain ice on the surface. It evaporates & is blown away on the solar wind. <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>
 
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