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Vega flight VV04 is GO for launch

Our friends over at Arianespace just tweeted some very good news coming out of today's launch readiness review: Vega, the IXV launcher, is go for lift off on 11 Feb 2015 at 14:00 CET.








from Rocket Science » Rocket Science http://ift.tt/1z1Aj0V

v

Our friends over at Arianespace just tweeted some very good news coming out of today's launch readiness review: Vega, the IXV launcher, is go for lift off on 11 Feb 2015 at 14:00 CET.








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Protocol for computing NMR chemical shifts

I have posted on the use of computed NMR chemical shifts and coupling constants to help aid in structure identification. The second edition of my book Computational Organic Chemistry has a largely all-new chapter on structure identification aided by computed spectra, especially NMR spectra. In my recent opinion piece speculating on challenges in computational organic chemistry,1 the first area I highlight is encouraging the larger use of computed spectra as an essential component of structure determination.


While more and more non-traditional computational users are employing quantum computations towards these problems, I suspect that many non-users are a bit wary about stepping into an arena they are not expert in, an arena chock-filled with acronyms and methods and potentially little guidance. While some very nice papers2-6 and web sites (Chemical Shift Repository (Cheshire) and DP4) do outline procedures for using computations in this fashion, they are not truly designed for the non-specialist.


Well, fear not any longer. Hoye and coworkers, synthetic chemists who have utilized computational approaches in structure determinations for a number of years, have written a detailed step-by-step protocol for using a standard computational approach towards structure determination.7 The article is written with the synthetic chemist in mind, and includes a number of scripts to automate many of the steps.


For the specialist, the overall outline of the protocol is fairly routine:



  1. Utilize MacroModel to perform a conformational search for each proposed structure, retaining the geometries within 5 kcal mol-1 of the global minimum.

  2. Optimize these conformations for each structure at M06-2x/6-31+G(d).

  3. For each conformation of each structure, compute the 1H and 13C chemical shifts, scale them, and determine the Boltzmann weighted chemical shifts

  4. Compare these chemical shifts with the experimental values using Mean Absolute Error


The article is straightforward and easily guides the novice user through these steps. Anyone unsure of how to utilize quantum chemical computations in structure determination is well advised to start with this article.


References



(1) Bachrach, S. M. "Challenges in computational organic chemistry," WIRES: Comput. Mol. Sci. 2014, 4, 482-487, DOI: 10.1002/wcms.1185.



(2) Lodewyk, M. W.; Siebert, M. R.; Tantillo, D. J. "Computational Prediction of 1H and 13C Chemical Shifts: A Useful Tool for Natural Product, Mechanistic, and Synthetic Organic Chemistry," Chem. Rev. 2012, 112, 1839–1862, DOI: href="http://ift.tt/1M6xzsc">10.1021/cr200106v.


(3) Bally, T.; Rablen, P. R. "Quantum-Chemical Simulation of 1H NMR Spectra. 2. Comparison of DFT-Based Procedures for Computing Proton-Proton Coupling Constants in Organic Molecules," J. Org. Chem. 2011, 76, 4818-4830, DOI: 10.1021/jo200513q.>


(4) Jain, R.; Bally, T.; Rablen, P. R. "Calculating Accurate Proton Chemical Shifts of Organic Molecules with Density Functional Methods and Modest Basis Sets," J. Org. Chem. 2009, 74, 4017-4023, DOI: 10.1021/jo900482q.


(5) Smith, S. G.; Goodman, J. M. "Assigning the Stereochemistry of Pairs of Diastereoisomers Using GIAO NMR Shift Calculation," J. Org. Chem. 2009, 74, 4597-4607, DOI: 10.1021/jo900408d.


(6) Smith, S. G.; Goodman, J. M. "Assigning Stereochemistry to Single Diastereoisomers by GIAO NMR Calculation: The DP4 Probability," J. Am. Chem. Soc. 2010, 132, 12946-12959, DOI: 10.1021/ja105035r.



(7) Willoughby, P. H.; Jansma, M. J.; Hoye, T. R. "A guide to small-molecule structure assignment through computation of (1H and 13C) NMR chemical shifts," Nat. Protocols 2014, 9, 643-660, DOI: 10.1038/nprot.2014.042.






from Computational Organic Chemistry http://ift.tt/1KAMFod

I have posted on the use of computed NMR chemical shifts and coupling constants to help aid in structure identification. The second edition of my book Computational Organic Chemistry has a largely all-new chapter on structure identification aided by computed spectra, especially NMR spectra. In my recent opinion piece speculating on challenges in computational organic chemistry,1 the first area I highlight is encouraging the larger use of computed spectra as an essential component of structure determination.


While more and more non-traditional computational users are employing quantum computations towards these problems, I suspect that many non-users are a bit wary about stepping into an arena they are not expert in, an arena chock-filled with acronyms and methods and potentially little guidance. While some very nice papers2-6 and web sites (Chemical Shift Repository (Cheshire) and DP4) do outline procedures for using computations in this fashion, they are not truly designed for the non-specialist.


Well, fear not any longer. Hoye and coworkers, synthetic chemists who have utilized computational approaches in structure determinations for a number of years, have written a detailed step-by-step protocol for using a standard computational approach towards structure determination.7 The article is written with the synthetic chemist in mind, and includes a number of scripts to automate many of the steps.


For the specialist, the overall outline of the protocol is fairly routine:



  1. Utilize MacroModel to perform a conformational search for each proposed structure, retaining the geometries within 5 kcal mol-1 of the global minimum.

  2. Optimize these conformations for each structure at M06-2x/6-31+G(d).

  3. For each conformation of each structure, compute the 1H and 13C chemical shifts, scale them, and determine the Boltzmann weighted chemical shifts

  4. Compare these chemical shifts with the experimental values using Mean Absolute Error


The article is straightforward and easily guides the novice user through these steps. Anyone unsure of how to utilize quantum chemical computations in structure determination is well advised to start with this article.


References



(1) Bachrach, S. M. "Challenges in computational organic chemistry," WIRES: Comput. Mol. Sci. 2014, 4, 482-487, DOI: 10.1002/wcms.1185.



(2) Lodewyk, M. W.; Siebert, M. R.; Tantillo, D. J. "Computational Prediction of 1H and 13C Chemical Shifts: A Useful Tool for Natural Product, Mechanistic, and Synthetic Organic Chemistry," Chem. Rev. 2012, 112, 1839–1862, DOI: href="http://ift.tt/1M6xzsc">10.1021/cr200106v.


(3) Bally, T.; Rablen, P. R. "Quantum-Chemical Simulation of 1H NMR Spectra. 2. Comparison of DFT-Based Procedures for Computing Proton-Proton Coupling Constants in Organic Molecules," J. Org. Chem. 2011, 76, 4818-4830, DOI: 10.1021/jo200513q.>


(4) Jain, R.; Bally, T.; Rablen, P. R. "Calculating Accurate Proton Chemical Shifts of Organic Molecules with Density Functional Methods and Modest Basis Sets," J. Org. Chem. 2009, 74, 4017-4023, DOI: 10.1021/jo900482q.


(5) Smith, S. G.; Goodman, J. M. "Assigning the Stereochemistry of Pairs of Diastereoisomers Using GIAO NMR Shift Calculation," J. Org. Chem. 2009, 74, 4597-4607, DOI: 10.1021/jo900408d.


(6) Smith, S. G.; Goodman, J. M. "Assigning Stereochemistry to Single Diastereoisomers by GIAO NMR Calculation: The DP4 Probability," J. Am. Chem. Soc. 2010, 132, 12946-12959, DOI: 10.1021/ja105035r.



(7) Willoughby, P. H.; Jansma, M. J.; Hoye, T. R. "A guide to small-molecule structure assignment through computation of (1H and 13C) NMR chemical shifts," Nat. Protocols 2014, 9, 643-660, DOI: 10.1038/nprot.2014.042.






from Computational Organic Chemistry http://ift.tt/1KAMFod

“We didn’t leave the Stone Age because we ran out of stone” [Greg Laden's Blog]

The latest in a series of Climate Change elevator pitches, being posted regularly at Peter Sinclair’s blog:



The first pitch is here.






from ScienceBlogs http://ift.tt/1vdMbvm

The latest in a series of Climate Change elevator pitches, being posted regularly at Peter Sinclair’s blog:



The first pitch is here.






from ScienceBlogs http://ift.tt/1vdMbvm

The State of Blogging 2015 [Uncertain Principles]

I was going to let Andrew Sullivan’s departure from blogging pass without comment– I haven’t been a regular reader of his stuff in around ten years, after all– but a couple of mysterious guys in dark suits showed up at the house and pointed out that as someone who started blogging in 2002, I would face dire consequences if I didn’t say anything at all. I offered to do two really short posts consisting of just links to Ezra Klein and Kevin Drum and the word “Indeed,” but they weren’t amused.


Truth be told, I do owe Sullivan a bit of a debt, and not just because he linked to me a few times and sent scads of readers this way. I gave up reading him back when he was making hyperbolic accusations of treason against people who opposed the war in Iraq, but like most bloggers of my generation, he was a big part of my introduction to the medium. And while I never agreed with him very much, thinking about exactly how he was wrong was a useful exercise for a few years there.


As for what this says about the medium as a whole, I really don’t have a whole lot to add to what Klein and Drum say. I agree that blogs in general are less conversational, and sort of miss the tighter community of the olden days. I also think Kevin’s got most of the reasons down– the combination of a shift to other media and the professionalization of blogging generally has fundamentally changed things, and there’s no going back. Professional blogs and media sites need to pay the bills, so they’re much less likely to engage in the kind of promiscuous linking that used to drive so much conversation. And a huge amount of conversation has moved to Twitter and Facebook, where it’s basically impossible to keep track of. One of my most successful posts of the last couple months (Thanks, Common Core) got a huge number of hits from Facebook, and I have absolutely no idea who was sending that traffic my way, or what they were saying. Because, Facebook– wherever it got off to, it wasn’t via people who are friends with me, so I couldn’t see any of it.


On the other hand, there’s a sense in which blogging really has transformed things. What blogs there are now feature much more professional sorts of writing, but at the same time, a lot of professional media outlets have adopted a much more blog-y tone. Something like Grantland, while it boasts editors and staff writers and all the trappings of a real media outlet, is just a massive group blog. You don’t see the cross-blog conversations that you used to back in the day, but the informal, conversational style that characterized early blogs has expanded hugely. As somebody who finds that style congenial, I regard this as a positive development, and for all his faults, Sullivan deserves some credit for that.


And while you can find the occasional piece claiming that Sullivan is the departing rat indicating that the medium is sinking, the truth is, blogs are way bigger than any one individual or site. Opening joke aside, I could perfectly well let his departure pass without comment, because he isn’t especially relevant to what I do any more, and hasn’t been for years.


Of course, there are some things about my part of the blogging ecosystem that aren’t especially healthy, at least from the standpoint of people getting paid. Scientific American pruned its blog network dramatically and ScienceBlogs is a shell of what it once was. There isn’t the same opportunity to get cash for science blogging that there once was. On the other hand, there are probably more for-free outlets now, and a greater diversity of styles of things, with videos and Tumblr photoblogs and Twitter chats and all that stuff


In thinking about this, I pulled up the Google Analytics stats for the blog for the first time in ages, and was a little surprised by just how little change there’s been. I have a vague sense that there was a drop-off in traffic back when National Geographic came in and most of the culture-wars stuff moved off ScienceBlogs (I don’t have access to those stats any more), but over the period I can see, everything has been remarkably consistent. I don’t think I’m supposed to share exact numbers, so I cropped out the vertical scale in the “featured image” above, but you can see the basically flat trend with the occasional big spike. (Most recently from huge numbers of aggrieved Patriots fans…)


Of course, there are some significant shifts in how that traffic works. Commenting fell off a cliff a while back, I’m not sure why. I think the departure of the culture warriors decreased overall traffic at ScienceBlogs, and I definitely get less incidental traffic from the other blogs on the network. Most of my current traffic comes from social media of various kinds, now– I have a Twitter feed for the blog that isn’t very widely followed, but anything I think is worthwhile I’ll promote on my own Twitter account, once when it goes live and again in the afternoon. That seems to keep things ticking along fairly smoothly.


I’ve been on a bit of a tear lately, blogging-wise, which is largely because I’ve been deeply unhappy about a bunch of stuff I can’t really talk about. Blogging serves as a kind of refuge from that for me– weirdly, my Happy Place turns out to be at Starbucks with my laptop. The frequency of posts is probably going to drop off dramatically in the near future, though, as we’re entering a more intense part of the academic term. Or maybe somebody will piss me off enough that I’ll just say “Fuck it” and blog even more. Tough call. Anyway, for the moment, I’m enjoying the writing and getting a lot of traffic, which is nice.


(I am, however, pretty terrible at turning those tweets and blog pageviews into book sales, alas. Which is one of the things making me grumpy these days…)


So, you know, it’s 2015: blogging is dead; long live blogging.






from ScienceBlogs http://ift.tt/1DXnFmW

I was going to let Andrew Sullivan’s departure from blogging pass without comment– I haven’t been a regular reader of his stuff in around ten years, after all– but a couple of mysterious guys in dark suits showed up at the house and pointed out that as someone who started blogging in 2002, I would face dire consequences if I didn’t say anything at all. I offered to do two really short posts consisting of just links to Ezra Klein and Kevin Drum and the word “Indeed,” but they weren’t amused.


Truth be told, I do owe Sullivan a bit of a debt, and not just because he linked to me a few times and sent scads of readers this way. I gave up reading him back when he was making hyperbolic accusations of treason against people who opposed the war in Iraq, but like most bloggers of my generation, he was a big part of my introduction to the medium. And while I never agreed with him very much, thinking about exactly how he was wrong was a useful exercise for a few years there.


As for what this says about the medium as a whole, I really don’t have a whole lot to add to what Klein and Drum say. I agree that blogs in general are less conversational, and sort of miss the tighter community of the olden days. I also think Kevin’s got most of the reasons down– the combination of a shift to other media and the professionalization of blogging generally has fundamentally changed things, and there’s no going back. Professional blogs and media sites need to pay the bills, so they’re much less likely to engage in the kind of promiscuous linking that used to drive so much conversation. And a huge amount of conversation has moved to Twitter and Facebook, where it’s basically impossible to keep track of. One of my most successful posts of the last couple months (Thanks, Common Core) got a huge number of hits from Facebook, and I have absolutely no idea who was sending that traffic my way, or what they were saying. Because, Facebook– wherever it got off to, it wasn’t via people who are friends with me, so I couldn’t see any of it.


On the other hand, there’s a sense in which blogging really has transformed things. What blogs there are now feature much more professional sorts of writing, but at the same time, a lot of professional media outlets have adopted a much more blog-y tone. Something like Grantland, while it boasts editors and staff writers and all the trappings of a real media outlet, is just a massive group blog. You don’t see the cross-blog conversations that you used to back in the day, but the informal, conversational style that characterized early blogs has expanded hugely. As somebody who finds that style congenial, I regard this as a positive development, and for all his faults, Sullivan deserves some credit for that.


And while you can find the occasional piece claiming that Sullivan is the departing rat indicating that the medium is sinking, the truth is, blogs are way bigger than any one individual or site. Opening joke aside, I could perfectly well let his departure pass without comment, because he isn’t especially relevant to what I do any more, and hasn’t been for years.


Of course, there are some things about my part of the blogging ecosystem that aren’t especially healthy, at least from the standpoint of people getting paid. Scientific American pruned its blog network dramatically and ScienceBlogs is a shell of what it once was. There isn’t the same opportunity to get cash for science blogging that there once was. On the other hand, there are probably more for-free outlets now, and a greater diversity of styles of things, with videos and Tumblr photoblogs and Twitter chats and all that stuff


In thinking about this, I pulled up the Google Analytics stats for the blog for the first time in ages, and was a little surprised by just how little change there’s been. I have a vague sense that there was a drop-off in traffic back when National Geographic came in and most of the culture-wars stuff moved off ScienceBlogs (I don’t have access to those stats any more), but over the period I can see, everything has been remarkably consistent. I don’t think I’m supposed to share exact numbers, so I cropped out the vertical scale in the “featured image” above, but you can see the basically flat trend with the occasional big spike. (Most recently from huge numbers of aggrieved Patriots fans…)


Of course, there are some significant shifts in how that traffic works. Commenting fell off a cliff a while back, I’m not sure why. I think the departure of the culture warriors decreased overall traffic at ScienceBlogs, and I definitely get less incidental traffic from the other blogs on the network. Most of my current traffic comes from social media of various kinds, now– I have a Twitter feed for the blog that isn’t very widely followed, but anything I think is worthwhile I’ll promote on my own Twitter account, once when it goes live and again in the afternoon. That seems to keep things ticking along fairly smoothly.


I’ve been on a bit of a tear lately, blogging-wise, which is largely because I’ve been deeply unhappy about a bunch of stuff I can’t really talk about. Blogging serves as a kind of refuge from that for me– weirdly, my Happy Place turns out to be at Starbucks with my laptop. The frequency of posts is probably going to drop off dramatically in the near future, though, as we’re entering a more intense part of the academic term. Or maybe somebody will piss me off enough that I’ll just say “Fuck it” and blog even more. Tough call. Anyway, for the moment, I’m enjoying the writing and getting a lot of traffic, which is nice.


(I am, however, pretty terrible at turning those tweets and blog pageviews into book sales, alas. Which is one of the things making me grumpy these days…)


So, you know, it’s 2015: blogging is dead; long live blogging.






from ScienceBlogs http://ift.tt/1DXnFmW

Medical Marijuana Policies Are Kind Of Childish [Aardvarchaeology]

Medical marijuana is just a backward strategy to get recreational marijuana legalised. It’s like the potheads twenty years ago who would praise hemp’s excellent properties as a fibre and fuel source. They didn’t care about any other fibre crops. It was a transparent ruse.


A medical intervention’s legality should be pushed by worldwide medical consensus, not by a regional cultural predisposition to enjoy the compound’s recreational use. Medical marijuana is a non-issue in European medicine.


That said, I believe the enormous public money put into the customs, legal and punitive systems to combat marijuana is pretty much thrown into the sea. A society with legal hard liquor will not have much comparative trouble with legal cannabis. Legalise it, tax it and put the money into alcoholism prevention & rehabilitation, I say.


So, USA: your medical marijuana policies are kind of childish. You’re transparently not promoting them because of any greater medical insight than the rest of the world has. You’re promoting them because you have a century-long solid cultural tradition to smoke weed recreationally. Just own it, OK?


This outburst was inspired by the current episode of the excellent Planet Money podcast from NPR.






from ScienceBlogs http://ift.tt/1A5jjwJ

Medical marijuana is just a backward strategy to get recreational marijuana legalised. It’s like the potheads twenty years ago who would praise hemp’s excellent properties as a fibre and fuel source. They didn’t care about any other fibre crops. It was a transparent ruse.


A medical intervention’s legality should be pushed by worldwide medical consensus, not by a regional cultural predisposition to enjoy the compound’s recreational use. Medical marijuana is a non-issue in European medicine.


That said, I believe the enormous public money put into the customs, legal and punitive systems to combat marijuana is pretty much thrown into the sea. A society with legal hard liquor will not have much comparative trouble with legal cannabis. Legalise it, tax it and put the money into alcoholism prevention & rehabilitation, I say.


So, USA: your medical marijuana policies are kind of childish. You’re transparently not promoting them because of any greater medical insight than the rest of the world has. You’re promoting them because you have a century-long solid cultural tradition to smoke weed recreationally. Just own it, OK?


This outburst was inspired by the current episode of the excellent Planet Money podcast from NPR.






from ScienceBlogs http://ift.tt/1A5jjwJ

This date in science: Great Meteor Procession


February 9, 1913. On this date, a strange meteor sighting occurred over Canada, the U.S. Northeast, Bermuda and some ships at sea, including one off Brazil. What happened that night is sometimes called the Great Meteor Procession of 1913, and it sparked decades of debate concerning what actually happened.


Why the word procession? The meteors in the annual showers that so many enjoy are different in several ways. Meteors in annual showers appear to radiate in all directions from a single point in the sky, called the radiant point. In contrast, the June 9. 1913 meteors appeared to cross the sky in formation, on nearly identical paths. Their pace across the sky was described as stately and measured. Also, as they plunge into Earth’s atmosphere and vaporize due to friction with the air, meteors in annual showers last only seconds. The 1913 meteors appeared to travel almost horizontally, nearly parallel to the Earth’s surface, and thus they remained visible to a single observer for about a minute, and the entire procession took several minutes to pass by.


Plus, rumblings and other strange sounds were reported, suggesting the 1913 meteors could have been relatively close to Earth when they disintegrated.



Canadian artist Gustav Hahn painted his impression of what the Great Meteor Procession looked like, in 1913. Image via Gustav Hahn/University of Toronto Archives. Used with permission.



Some astronomers later concluded that – because all sightings of the meteor procession occurred along a great circle arc – the source had been a small, short-lived natural satellite of Earth – a temporary second moon. Other theories attempted to prove here was a radiant point for this shower, just as for any ordinary meteor shower.


The densely populated U.S. Northeast was cloudy on the evening of February 9, 2013. So 30 million potential observers were for the most part unaware of the phenomenon. A 1913 report in the Journal of the Royal Astronomical Society of Canada by Clarence Chant, who collected over 100 eye-witness reports of the event, described the scene like this:



A huge meteor appeared traveling from northwest by west to southeast, which, as it approached, was seen to be in two parts and looked like two bars of flaming material, one following the other. They were throwing out a constant stream of sparks and after they had passed they shot out balls of fire straight ahead that travelled more rapidly than the main bodies. They seemed to pass over slowly and were in sight about five minutes. Immediately after their disappearance in the southeast a ball of clear fire, that looked like a big star, passed across the sky in their wake. This ball did not have a tail or show sparks of any kind. Instead of being yellow like the meteors, it was clear like a star.



Enjoying EarthSky so far? Sign up for our free daily newsletter today!



The red dots mark locations where the Great Meteor Procession of 1913. View larger. Map via Sky & Telescope and Texas State University.



Don Olson of Texas State University and Steve Hutcheon of the Astronomical Association of Queensland, Australia – have studied this phenomenon. Sifting through a vast array of archival material, the team discovered seven ship reports, all previously unknown, extending the established track of the procession by an additional thousand miles. They reported their results in a 2013 issue of Sky & Telescope magazine. Read more about Olson and Hutcheon’s findings here.


Meanwhile, the exact origin of the meteors in the 1913 meteor procession may never be known for sure.


Bottom line: Today is the anniversary of what some called the Great Meteor Procession. Occurring on February 9, 1913, this event featured bright meteors, or fireballs, that moved in measured, stately way – on identical paths – across the night sky.


EarthSky’s top 10 tips for meteor-watchers






from EarthSky http://ift.tt/1zBihX7

February 9, 1913. On this date, a strange meteor sighting occurred over Canada, the U.S. Northeast, Bermuda and some ships at sea, including one off Brazil. What happened that night is sometimes called the Great Meteor Procession of 1913, and it sparked decades of debate concerning what actually happened.


Why the word procession? The meteors in the annual showers that so many enjoy are different in several ways. Meteors in annual showers appear to radiate in all directions from a single point in the sky, called the radiant point. In contrast, the June 9. 1913 meteors appeared to cross the sky in formation, on nearly identical paths. Their pace across the sky was described as stately and measured. Also, as they plunge into Earth’s atmosphere and vaporize due to friction with the air, meteors in annual showers last only seconds. The 1913 meteors appeared to travel almost horizontally, nearly parallel to the Earth’s surface, and thus they remained visible to a single observer for about a minute, and the entire procession took several minutes to pass by.


Plus, rumblings and other strange sounds were reported, suggesting the 1913 meteors could have been relatively close to Earth when they disintegrated.



Canadian artist Gustav Hahn painted his impression of what the Great Meteor Procession looked like, in 1913. Image via Gustav Hahn/University of Toronto Archives. Used with permission.



Some astronomers later concluded that – because all sightings of the meteor procession occurred along a great circle arc – the source had been a small, short-lived natural satellite of Earth – a temporary second moon. Other theories attempted to prove here was a radiant point for this shower, just as for any ordinary meteor shower.


The densely populated U.S. Northeast was cloudy on the evening of February 9, 2013. So 30 million potential observers were for the most part unaware of the phenomenon. A 1913 report in the Journal of the Royal Astronomical Society of Canada by Clarence Chant, who collected over 100 eye-witness reports of the event, described the scene like this:



A huge meteor appeared traveling from northwest by west to southeast, which, as it approached, was seen to be in two parts and looked like two bars of flaming material, one following the other. They were throwing out a constant stream of sparks and after they had passed they shot out balls of fire straight ahead that travelled more rapidly than the main bodies. They seemed to pass over slowly and were in sight about five minutes. Immediately after their disappearance in the southeast a ball of clear fire, that looked like a big star, passed across the sky in their wake. This ball did not have a tail or show sparks of any kind. Instead of being yellow like the meteors, it was clear like a star.



Enjoying EarthSky so far? Sign up for our free daily newsletter today!



The red dots mark locations where the Great Meteor Procession of 1913. View larger. Map via Sky & Telescope and Texas State University.



Don Olson of Texas State University and Steve Hutcheon of the Astronomical Association of Queensland, Australia – have studied this phenomenon. Sifting through a vast array of archival material, the team discovered seven ship reports, all previously unknown, extending the established track of the procession by an additional thousand miles. They reported their results in a 2013 issue of Sky & Telescope magazine. Read more about Olson and Hutcheon’s findings here.


Meanwhile, the exact origin of the meteors in the 1913 meteor procession may never be known for sure.


Bottom line: Today is the anniversary of what some called the Great Meteor Procession. Occurring on February 9, 1913, this event featured bright meteors, or fireballs, that moved in measured, stately way – on identical paths – across the night sky.


EarthSky’s top 10 tips for meteor-watchers






from EarthSky http://ift.tt/1zBihX7

February 2015 Open Thread [Deltoid]

More thread.






from ScienceBlogs http://ift.tt/1ANbSKj

More thread.






from ScienceBlogs http://ift.tt/1ANbSKj

adds 2