tag:blogger.com,1999:blog-9094742788006644220.post3501628840646244955..comments2020-11-09T07_43_07.776-08_00Comments on Mike Brown's Planets: Comets!Unknownnoreply@blogger.comBlogger14125tag:blogger.com,1999:blog-9094742788006644220.post-2520514595340136682015-02-02T03_48_49.890-08_002015-02-02T03_48_49.890-08_00Great shoot Mr. Brown, that was an amazing comet t...Great shoot Mr. Brown, that was an amazing comet theredewapokerhttp://hokipoker.com/noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-26312287016969661612013-04-04T09_13_57.003-07_002013-04-04T09_13_57.003-07_00Anno 2013, which object is considered to be the fu...Anno 2013, which object is considered to be the furthest in the solar system?<br />Is it 1000 Km large Sedna (518 AU and 12000 years orbit) or small 150 Km 2006 SQ372 (1500 AU and 22500 years orbit)?<br />...Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-79843615283652810042013-03-26T23_14_58.524-07_002013-03-26T23_14_58.524-07_00NASA wants to prove existance of extraterrestrial ...NASA wants to prove existance of extraterrestrial primitive or advanced lifejudi Bola Onlinehttp://www.bolanation.comnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-59417519042145221122013-03-26T04_06_36.893-07_002013-03-26T04_06_36.893-07_00NASA wants to prove existance of extraterrestrial ...NASA wants to prove existance of extraterrestrial primitive or advanced life, but we actually have such proofs for microorganisma,...it is publised also in that mentioned web page<br />PavelAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-63799017909294438022013-03-26T04_01_20.668-07_002013-03-26T04_01_20.668-07_00here is also published theory how big world plague...here is also published theory how big world plagues were tied with arrivals of comets to perihelia,...probably old viruses,...from comets are responsible,...so not only impacts of fragments but also old preserved microorganisma could trigger some catastrophe,.. http://journalofcosmology.com/Panspermia10.html<br />PavelAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-47657462183926688572013-03-26T03_53_08.834-07_002013-03-26T03_53_08.834-07_00Nice photos,..we had bad weather in the most part ...Nice photos,..we had bad weather in the most part of Europe these last weeks,..so I wasn[t successful in observing ,..but here are some the oldest known depiction of comets from China,...https://www.google.sk/search?hl=sk&amp;site=imghp&amp;tbm=isch&amp;source=hp&amp;biw=1280&amp;bih=575&amp;q=mawangdui+silk+comets&amp;oq=mawangdui+silk+comets&amp;gs_l=img.3...1096.7984.0.8223. PavelAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-21105054022054526132013-03-16T09_19_09.061-07_002013-03-16T09_19_09.061-07_00G. Smith.... Special events like comets are publi...G. Smith....<br /><br />Special events like comets are publicized in so many places...we want Mike to stay busy finding more cool stuff in the outer solar system! <br /><br />Sky and Telescope&#39;s page on what is out this week, Astronomy magazine, Universe Today, this particular comet has been anticipated since last fall. Your local astronomy club is also a great resource. Your local planetarium. If you want to know more about fun visual events in the night sky, there are numerous ways to find out. Amateurs are already observing C/2012 S1 (Comet ISON) with telescopes, we hope it will be so bright you can&#39;t miss it in the sunrise AND sunset skies in November and December. <br /><br />Not only are there lots of great places to find out how to observe ephemeral events, many also include the science involved as well. And I haven&#39;t even mentioned computer planetarium programs, your smartphone, etc that can produce custom views for your exact location. <br /><br />Enjoy the sky! If you have clear weather, you can still find this comet in the sunset.<br /><br />Theo Wellington<br />Barnard-Seyfert Astronomical Society / Nashville<br />Sudekum Planetarium / Nashvilledanikamomhttps://www.blogger.com/profile/15233079279530863337noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-76808321929118945142013-03-15T16_55_03.528-07_002013-03-15T16_55_03.528-07_00Dear Mr. Brown: I did not know that you lived in ...Dear Mr. Brown:<br /><br />I did not know that you lived in &quot;Smog Angeles,&quot; although it has balmy weather throughout the year, it also has a lot of air and light pollution which are obstacles to clear viewing of the heavens. As an Angelino, there is access to some great astronomical assets within an hour&#39;s drive including Griffith and Mount Wilson Observatories and JPL; the latter two I am eager to visit.<br /><br />Comets are the unsung heroes of the Solar System, as they may have brought water and perhaps life in the form of organic molecules, amino acids or even simple (micro) organisms to Earth.<br /><br />Comets also may bring destruction as in the case of the infamous Tunguska event in 1908 where perhaps a comet slammed into Siberia with the force that was 1,000 times greater than the nuclear bomb that the U.S.A. dropped over Hiroshima, Japan during World War Two. <br /><br />Where do comets come from, perhaps the Oort cloud if such a place even exists? If comets that are made of water ice pelted the Solar System billions of years ago, then why is water (in any form) not much more common, i.e. it should be (abundant) on most rocky worlds from Earth/Moon to the Oort cloud, but it is not, why? <br /><br />P.S. Please give us a head&#39;s-up at least several days in advance, next time a special event like the comet you wrote about along with instructions regarding how to find it.<br /><br />Thank you.G. Smithnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-47086655660015358252013-03-15T11_48_19.769-07_002013-03-15T11_48_19.769-07_00It&#39;s just fun to imagine how many of us were o...It&#39;s just fun to imagine how many of us were out that night, like a wave across the US as the Earth tuned and we came to sunset with that lovely young Moon. I was in the best local west view....a WalMart parking lot...with some folks who meant to be there and some who wandered over wondering what we were looking at. Enjoy the view from Hawaii, I envy that, we&#39;re rained out here in Nashville for several days. <br /><br />Tripod, yes, and two second delay if you can...I&#39;ve found most of my jitter was at the button push. :-)<br />danikamomhttps://www.blogger.com/profile/15233079279530863337noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-55356501555823271702013-03-15T06_57_20.855-07_002013-03-15T06_57_20.855-07_00That is a very nice back yard view (and comet)! F...That is a very nice back yard view (and comet)!<br /><br />For exposure, I recently tried to calculate how fast the sky moves in pixels/s if you use a tripod without tracking for an object near the ecliptic:<br /><br /> pixels/s = f * Rx * pi / (43200 * d)<br /><br />where f is the focal length in mm, Rx is the horizontal resolution in pixels, and d is the horizontal width of the sensor in mm (36mm for full frame).<br /><br />For a 300mm lens on micro four thirds (or 600mm on full frame), this results in about 5 pixels/s, so you&#39;ll get motion blur if you go much above 1/5 second exposures.Klaushttps://www.blogger.com/profile/01220976408151969252noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-29996786127785089332013-03-13T21_01_52.018-07_002013-03-13T21_01_52.018-07_00What a gift! Thanks so much, Dr. Brown...What a gift! Thanks so much, Dr. Brown...Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-4518025711267056962013-03-13T11_30_16.512-07_002013-03-13T11_30_16.512-07_00I could see it naked eye, but only after I first f...I could see it naked eye, but only after I first found it with the binocs and knew exactly where to look. It was tough. There are .5-2 second exposures. And clearly I need a more stable tripod!Mike Brownhttps://www.blogger.com/profile/04402191029077523538noreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-91743734803075394352013-03-13T07_35_53.646-07_002013-03-13T07_35_53.646-07_00Thanks for the pictures! Were these taken at diffe...Thanks for the pictures! Were these taken at different exposure settings (or at least the first different from the last three)? I think the first picture brings home the fact clearly how tough it is to spot it. All those 2-3 sec exposures that I&#39;ve been looking at in the web have fooled me into thinking that it was fairly easy. Two evenings with binocs, and one with a Moon a few degree away, haven&#39;t helped so far. :(Navneethnoreply@blogger.comtag:blogger.com,1999:blog-9094742788006644220.post-7131458869262319092013-03-12T22_34_10.550-07_002013-03-12T22_34_10.550-07_00great pictures!! great pictures!! Anonymoushttps://www.blogger.com/profile/06414925335598929572noreply@blogger.com