tag:blogger.com,1999:blog-9094742788006644220.post5731190478968843862..comments2020-11-09T07_43_07.776-08_00 Unknownnoreply@blogger.comBlogger33125tag:blogger.com,1999:blog-9094742788006644220.post-49223314782334488012014-08-29T10_47_23.642-07_002014-08-29T10_47_23.642-07_00 hiiiiiiiiiiiiiiiii !!!!!!!!! :) Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-36522015699746064182013-01-12T05_46_56.804-08_002013-01-12T05_46_56.804-08_00 I enjoy your blog, and have nominated you for a Very Inspiring Blogger Award. The details are at http://jameswight.wordpress.com/2013/01/12/very-inspiring-blogger-award/<br /><br />Hoping you will resume blogging soon! James Wighthttp://jameswight.wordpress.comnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-16280663695971916012012-11-26T06_36_31.634-08_002012-11-26T06_36_31.634-08_00 Hi Mike,<br /><br />Of as much interest as the relative diameters of Eris and Pluto are, the diameters of their orbits is of even greater interest.<br /><br />You got a mention in this article I wrote a while ago:<br /><br />http://tallbloke.wordpress.com/2012/04/30/emile-sevin-sur-la-structure-du-system-solaire/ Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-15922102150403515772012-11-06T05_08_52.786-08_002012-11-06T05_08_52.786-08_00 Unfortunately, the myth does not matter. Eris is the planet of success and good fortune in astrology. Unfortunately you are not a good enough astrologer to prove that or understand that or even comment on that. Therefore science does not listen to astrology. One day it will change. But as long as astrologers believe in myth, it will not change.<br /> Markushttp://www.rosecast.comnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-24821981966620218382012-11-04T13_53_03.597-08_002012-11-04T13_53_03.597-08_00 Is there a map showing where Eris, Sedna and company are in the Solar System? Anonymoushttps://www.blogger.com/profile/00858330719227987494noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-15124807811535005092012-10-21T12_45_46.345-07_002012-10-21T12_45_46.345-07_00 Just bought your book and am really enjoying it! I know how it ends, with this &quot;dwarf planet&quot; nomenclature that I frankly think will be tossed by a future generation. For me, Pluto will always be a planet, and it sounds like Eris is the tenth :)<br /><br />I know there are other, smaller TNOs but my admittedly lame and purely poetic definition is a sphere that orbits that sun, and is at least as big as Pluto. Not IAU caliber, I admit.<br /><br />Eric Martin emartinhttps://www.blogger.com/profile/03768602752942144530noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-27072707617522094342012-05-19T10_58_51.061-07_002012-05-19T10_58_51.061-07_00 Mike Brown! Your blog is my crack! You&#39;ve deprived me for many moons now! Write more! Please? Michael Joseph John Pawelczyk McClellanhttps://www.blogger.com/profile/05796519065290727037noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-5834060348248548632012-05-12T18_49_42.889-07_002012-05-12T18_49_42.889-07_00 Hi Mike, <br />Last week my in-laws dragged me to the Kennedy Space Center tour and since I passed on the IMAX show because it was 3D, I stumbled upon your book at the gift shop while waiting and bought it on a whim, because quite frankly it was the only book in there that looked remotely enjoyable to me. Glad I did! I now have an appreciation for the sky and am almost tempted to buy a telescope? and try to figure out where the heck all those planets/stars are so I can show my 5-year old son. Before, I would just point out the moon to him and now I feel ashamed of my nonchalance towards the night sky. Anyway, great book even for a non-techy like myself. Even my CS-professor husband paged through it with interest, and we laughed at some similarities of what must be the researcher state-of-mind (same coffee shop, same order, etc). Thanks for opening my eyes to a totally different world. And best to little Lilah! Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-13657380859121033382012-03-05T09_54_49.403-08_002012-03-05T09_54_49.403-08_00 Mike, I&#39;ve noticed that the numbers you have published recently for Eris&#39; percentage of eccentricity, degree of inclination and semi-major axis are a little different than those that are commonly cited. Can you tell us why this is? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-66074771729588563702011-12-09T23_13_13.859-08_002011-12-09T23_13_13.859-08_00 Johh. I&#39;ll try harder next time :)<br /><br />Rudy Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-42801622293630449202011-12-02T09_52_48.109-08_002011-12-02T09_52_48.109-08_00 Thank you, KenN and djlactin, for your explanation of diameter estimation from star transits.<br /><br />Rudy, that didn&#39;t help!<br />John Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-5070642755594872092011-11-16T12_21_11.036-08_002011-11-16T12_21_11.036-08_00 Screw that, the Solar System is a huge place! There&#39;s room for everybody, even Sedna (and maybe Tyche)! Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-11676147903892361132011-11-11T05_32_05.162-08_002011-11-11T05_32_05.162-08_00 The primary planets in the Solar System are: Mercury, Venus, Earth, Mars, Vesta, Juno, Ceres, Pallas, Jupiter, Saturn and Uranus. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-23381451476872573112011-11-09T10_19_47.468-08_002011-11-09T10_19_47.468-08_00 Hi Mike,..Didn&#39;t you participated on atempt to observe asteroid 2005 YU55?<br /><br />http://www.universetoday.com/90805/live-webcast-as-keck-telescope-attempts-images-of-asteroid-2005-yu55/<br />much smaller eccentricity but direction cca like Elenin,..Pavel Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-58981186624405030932011-11-02T16_00_48.336-07_002011-11-02T16_00_48.336-07_00 I believe that the matter of size (if by size you mean &quot;diameter&quot;) is in itself problematic.<br /><br />Let me elaborate a bit more.<br />Unless both Pluto and Eris are perfect spheres and not someting more akin to a triaxial ellipsoid or even a pear shaped body, there in not only one dimension that can emcompass size.<br /><br />If you want to go by &quot;size&quot;, meaning the M in the Système international of units, then you would have to have it as &quot;diameter of a sphere with equal volume&quot;. So there is no Pluto being &quot;bigger&quot; than Eris by one centimeter, inch, foot or meter. It could well be that Pluto&#39;s largest dimension is larger by 2 kms. than on of the &quot;diameters&quot; of Eris but contrarywise there is a shorter dimension accross Pluto which 1 Km. shorter than the longest dimension on Eris.<br />At the end of this comment the issue is that the answer to the question of which is bigger? Might be &quot;what is it meant by bigger?<br />Bigger equatorial diameter? Bigger ESD? (Equivalent spherical diameter) <br />If One of the bodies is 2326 +/-12 Kms. and the other is 2400 +/- 50 Are this numbers refered to ESD (equivalent spherical diameter)or to one maximal chord?<br />What is uncontroversial is that ERIS IS 27% MORE MASSIVE THAN PLUTO.<br />As a corollary we can say that the eridian density is at least 20% greater than the plutonian.<br />Lets just hope that New Horizons can give us estimates of Pluto&#39;s J2 at the end of the day.<br /><br />Rudy Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-87708083821047827022011-10-31T19_26_39.613-07_002011-10-31T19_26_39.613-07_00 Pluto and Eris are neither twins nor rivals. Why does everything have to be a contest? Earth and Venus have similarities, as do Uranus and Neptune. And how can we be certain which object is bigger unless and until we visit BOTH of them? Yes, Eris is a lot further away, but we should at least start thinking about a mission there. Every mission has taught us that we don&#39;t really know much about a world until we go there. The whole notion of having to make a decision based on which object is bigger ends up being downright sily, just like the idea of &quot;bragging rights.&quot; These are all planets of our solar system; they are all different, but they are all fascinating. And I disagree about their not being interesting to people. Clearly, all this coverage and all the books and articles that continue to be written show that the outer solar system is a place that interests a great number of people. I think there will eventually be a reconsideration of the IAU vote to allow for the inclusion of dwarf planets and of exoplanets as well. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-1500865980639052712011-10-31T13_24_42.432-07_002011-10-31T13_24_42.432-07_00 What I appreciate most about you and your work, Dr. Brown, is that you put great care and emphasis on accuracy, no matter how popular/unpopular that stance is.<br /><br />Seems to me that saying Eris and Pluto are alike because they are roughly the same size is like saying two people are alike because they are both 5&#39;-11&quot; tall--even though one weighs 300 pounds with blond hair and blue eyes, and the other is a dark-eyed brunette who is height-weight proportionate. Seems like it&#39;s a weird way to try to correlate two very dissimilar objects via one of their very few common denominators... Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-63279949964916060402011-10-30T19_12_14.961-07_002011-10-30T19_12_14.961-07_00 I&#39;ve also heard Venus described as &quot;Earth&#39;s Evil Twin&quot;. It occurs to me that twins don&#39;t have to be identical. They merely have to be siblings born from the same mother at the same time.<br /><br />Presumably, Earth and Venus formed more or less together, and likewise Uranus and Neptune. How about Pluto and Eris?<br /><br />Bob Shepard of Denver Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-65503957528620421022011-10-30T17_03_22.083-07_002011-10-30T17_03_22.083-07_00 It would be really ridiculous to the point where I LOL, if in three years New Horizons identifies and proves that Pluto is not only larger than Eris, but the largest of the known dwarf planets, even if by an inch. If this is the case, all who identified Eris as the larger of the two, will have egg on their face for bringing the sudden and urgent need to create new definitions and classifications for planets to the IAU.<br /><br />Okay, so density is far superior and important to me, as a drop of matter from the center of a black hole, may contain more matter than the entire Milky Way (except for the black hole at the center of The Milky Way) . Most interesting prospects for life sustaining worlds (in our solar system) include Enceladus, Europa, Ceres and Titan, all of which are much smaller than a gas giant such as Saturn, whose density is less than that of water. <br /><br />I do not care if a world is the size of a marble if it harbors life. Although it is possible that life exists on gaseous worlds, I think the scientific community believes it to be improbable (perhaps based on our narrow- minded view of what life needs to exist), therefore less likely to exist on such a world.<br /><br />Is it not mass that determines a world&#39;s shape, size, ability to clear its neighborhood etc.; it&#39;s certainly not a condition of size alone; as with Saturn, of great size does not mean of great density.<br /><br />So what if Eris is 27% more massive than Pluto, what does it point to regarding differences in their origin, age, composition or other things of interest? Specifications of a world can be interesting, but what science can do with such information can be very interesting. Answers to questions such as &quot;how can worlds which reside in the same region be so different (if this is the case),&quot; &quot;how were such worlds made&quot; and &quot;what is the natural history of these worlds,&quot; is of greater interest to me. <br /><br />I am not going to be waiting on the edge of my seat for New Horizons to make precise measurements of small frozen, red, blue or purple worlds. There is a lot more out there than we can know at this time, but one thing is for sure, we will continue to find worlds, because there are an infinite amount of them in the universe, just waiting to be discovered. <br /><br />May the search continue, forever... George Smithnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-44263715413845133692011-10-30T01_15_19.761-07_002011-10-30T01_15_19.761-07_00 Hi Mike,...what do you think about these works:http://arxiv.org/PS_cache/arxiv/pdf/1102/1102.0212v6.pdf ?<br />(On the anomalous secular increase of the eccentricity of<br />the orbit of the Moon,...)<br />Did you find or could you find any similar disproportions in motions of planetoids (Eris, Sedna,Pluto,..)? Pavel Smutny Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-53629314423363174602011-10-29T09_38_42.179-07_002011-10-29T09_38_42.179-07_00 did mike brown has studied why there is a lot of Objects around 67 UA????? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-52027819700296228062011-10-29T02_48_29.800-07_002011-10-29T02_48_29.800-07_00 Congratulations on the accuracy of your measurement!<br /><br />I would have given you the gold star you request, but I have this feeling you&#39;d actually prefer a ball of reddish, dirty ice instead... :-) Brianhttp://brianvds.blogspot.comnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-81811187498050926262011-10-29T01_20_28.092-07_002011-10-29T01_20_28.092-07_00 @mikeemmert: The Moon doesn&#39;t have the same density as the Earth, either.<br /><br />This situation is expected when a satellite is created by a collision of a smaller body with that of a differentiated larger body. The satellite ends up being composed of bits of the smaller body (usually less dense than the larger body) plus surface (less dense) bits of the larger. Hence it&#39;s no surprise when a satellite is less dense than its primary. Dan Tilquenoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-46926094875568735782011-10-28T23_38_15.905-07_002011-10-28T23_38_15.905-07_00 Re: transit estimation of diameter. If you have two observations of the transit from different locations, the timings of the star winking out and back on give two chords. The four endpoints of the chords uniquely define a circle (even if neither of the chords corresponds to the diameter). Estimate quality would increase with the number of observations/chords, but I think even one full chord and a tangent point would suffice. djlactinnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-386467927072026922011-10-28T15_18_32.824-07_002011-10-28T15_18_32.824-07_00 John D,<br /> in reports I have seen, there were multiple measurements from a few observatories so combining them revealed longest transit as diameter.<br /><br />JohnD said...<br /><br /> How do you know the chord across which Eris&#39; disc crossed the star? Are your &#39;ephemera&#39; for Eris (? orbital data) good enough to be certain where it is between a diameter and a tangent?<br /> JohnD Ken Nhttps://www.blogger.com/profile/05590786211259640387noreply@blogger.com