![]()
Sagan y la tabla periódica
Este vídeo es un fragmento del episodio 9 de COSMOS, en el que el gran Carl Sagan («el maestro de todos nosotros«) explica el origen de los elementos químicos, la ordenación de la Tabla Periódica y la estabilidad de los átomos.
La explicación la da desde el Laboratorio Cavendish, un lugar fascinante en la historia de la ciencia, del que hemos hablado en el programa El Nanoscopio.
[youtube]http://www.youtube.com/watch?v=71NkR1Mtolk[/youtube]
Nota: Este post participa en el XXVII Carnaval de Química que aloja el blog Educación Química.
Bernardo Herradón CSIC
Worth saying this site reads better than most paid newsletters I have tried, and a stop at focusbuildsenergy confirmed that comparison, the bar for free content is often lower than for paid but this site clears the paid bar consistently and that says something about the editorial approach behind the work being published here regularly.
Taking the time to read carefully here has been worthwhile for the past hour, and a look at clarityguidesgrowth extended the worthwhile reading, the calculation of return on reading time spent is something I do informally and this site has been producing positive returns across multiple sessions during the last week of regular visits and reads.
Now recognising the editorial wisdom of letting some questions remain open at the end, and a look at heritagetrustbond continued that intellectual honesty, content that does not force closure on contested questions is content that respects the limits of knowledge and this site has clearly developed the maturity to know when to leave space.
Honestly enjoyed every minute spent here, that is not something I say lightly, and a look at unifiedcapitalgroup confirmed I will be back, the bar for spending time online is high for me these days but this site clears it without effort which is high praise indeed from this reader who is usually rather demanding.
I really like how the writer keeps the tone friendly without sounding fake or overly polished, and after a stop at clarityguidesdecisions the same calm pace was there, no rushing to make a point and no padding either, just clean honest writing that I can respect and come back to later again.
Looking at this from the perspective of someone tired of generic content the contrast is striking, and a look at clarityfocus maintained that distinctive feel, sites with strong editorial identity stand out against the bland background of algorithmic content and this one has clearly developed an identity worth recognising through careful attention.
A piece that was confident enough to leave some questions open rather than forcing closure, and a look at ideapipeline continued that intellectual honesty, content that admits the limits of its scope is more trustworthy than content that pretends to total understanding and this site has the right calibration on certainty consistently.
Took a screenshot of one section to come back to later, and a stop at forwardpathenergized prompted another saved tab, the urge to capture and revisit specific pieces of content is something I rarely feel but when I do it tells me the work is worth more than the average passing read for sure.
Took a few notes from this post, the points are easy to remember without needing to come back and check, and a look at growthsignalpath added a couple more, the kind of place that sticks in the memory long after the browser tab has been closed for the day which says a lot really.
Now feeling the small relief of finding writing that does not condescend, and a stop at ideafocus extended that respect for readers, content that treats its audience as capable adults rather than as people to be managed produces a different reading experience and this site has clearly chosen the respectful approach across all pieces.
Liked that the post acknowledged complications rather than pretending they did not exist, and a stop at claritypowerschoices continued that honest framing, sites that handle complexity with care rather than papering it over with simplifying claims are doing real intellectual work and this one is clearly in that category based on what I have read.
Started thinking about my own writing differently after reading, and a look at thinkactflow continued that reflective effect, content that influences how I work rather than just informing what I know is content with the highest kind of impact and this site has triggered some of that reflective influence today on me.
Just wanted to drop a quick note saying this was a useful read on a topic I have been circling, no fluff, and a stop at directionenergizesgrowth added a few extra points that fit the same simple style which makes the whole site feel coherent rather than thrown together by many different writers with different goals.
Just sat with this for a bit longer than I usually would because the points are worth thinking about, and after ideamotionlab I had even more to chew on, the kind of post that nudges your thinking forward without forcing the issue is something I have always appreciated in good writing online.
Closed the laptop after this and let the ideas settle for a few hours, and a stop at businessbondnetwork similarly rewarded reflective time, content that benefits from sitting with rather than racing past is the kind I want more of and the kind that this site appears to consistently produce week after week here.
Considered alongside other sources I have been reading this one consistently rises to the top, and a stop at growthalignment maintained that top ranking, the informal ongoing comparison between sources is something I do whenever reading on a topic and this site keeps coming out near the top of those comparisons over many sessions.
Closed the tab feeling I had spent the time well, and a stop at collaborativegrowthcircle extended that feeling across more pages, the test of whether time on a site was well spent is one I apply silently after closing tabs and very few sites pass it but this one passed it cleanly today afternoon clearly.
Picked up something useful for a side project, and a look at unitypathbond added another piece I will incorporate, content that connects to specific projects I am working on is content with practical utility and the practical utility of this site is showing up across multiple posts I have read in the last hour or so.
Worth flagging this site to a few specific friends who would appreciate the editorial sensibility, and a look at focusdefinesdirection added more pages I will mention to them, recommending sites to specific people requires understanding both the site and the person and this site is making those personalised recommendations easy and natural for me.
Halfway through reading I knew this would be one to bookmark, and a look at actionintelligence confirmed that early intuition, when bookmark intent forms before finishing a post you know the writing has cleared a quality bar that most content fails to clear and this site has cleared it on multiple visits already.
Now considering whether the post would translate well into a different form, and a look at futurepartnershub suggested similar versatility, content that could move into other media without losing its substance is content that has been built around ideas rather than around format and this site reads as idea first throughout posts.
The tone stayed consistent across the whole post which is harder than it looks for longer pieces, and a look at trustedbondcircle continued the same voice, this kind of editorial consistency is a sign of either a single careful writer or a tightly run team and either is impressive today across the broader media environment.
Liked the careful selection of which details to include and which to skip, and a stop at forwardmotionactivated reflected the same editorial judgement, knowing what to leave out is just as important as knowing what to include and this site has clearly figured out where that line sits for the topics it covers regularly.
Now thinking I want more sites built on this kind of editorial foundation, and a stop at directionalshift extended that wish into a broader hope, sites built on substance and care rather than on metrics and growth are the kind of sites I want to see more of and this one is a small example worth supporting.
Found a small mental shift after reading this, the framing here is just a bit different from the standard takes online, and a look at claritymomentum extended that fresh perspective across more material, the rare site whose voice actually changes how you think about something rather than just confirming existing beliefs.
Adding this to my list of go to references for the topic, and a stop at focuscreatesmovement confirmed the rest of the site deserves the same, definitely the kind of resource that earns its place rather than getting forgotten the moment the next interesting article shows up in my feed somewhere else on the web.
Worth recognising the specific care that went into how this post ended, and a look at signalactivatesgrowth maintained the same careful conclusions, endings are where most blog content falls apart and this site has clearly invested in the closing stretches of its pieces rather than letting them simply trail off when energy fades.
Reading this back to back with a similar piece elsewhere made the quality difference obvious, and a stop at claritybuildsprogress only widened the gap, comparing content side by side is a useful exercise and the gap between this site and average competitors in the space is large enough to be noticeable from the first paragraph.
Quietly the writers approach to the topic differs from the dominant takes I have been encountering, and a stop at progressmoveswithfocus extended that distinctive approach, content that maintains a different perspective without explicitly arguing against the dominant ones is content with confident editorial identity and this site has that confidence throughout pieces.
Speaking from the perspective of a fairly demanding reader the writing here clears the bar consistently, and a look at focuschannelsenergy continued clearing that bar, the calibration of demanding reader is something I apply to all sources and this site has been one of the few that handles the demanding reading well across pieces sampled.
Picked this up between two other things I was doing and got drawn in completely, and after visiondrivenpartnership my original tasks were completely forgotten for a while, content that derails a workflow in a positive way by being more interesting than what you were already doing is rare and worth recognising clearly.
Looking for similar voices elsewhere has come up empty in my recent searches, and a stop at focusbuildsvelocity extended the search frustration, the rare site that does what no other does in quite the same way is precious and this one has clearly developed a particular approach that I have not been able to find duplicates of.
Honestly impressed by how much useful content sits in such a small post, and a stop at directionalmap confirmed the rest of the site packs a similar punch, density without confusion is a hard balance to strike and this site has clearly cracked the code on it across many different topic areas covered.
Will be passing this along to a few people who would benefit from the perspective shared here, and a stop at actiondirection only added to what I will be sharing, this kind of generous content deserves to circulate widely rather than getting buried in some search engine algorithm tweak that pushes it down the rankings.
Honestly this hits the sweet spot between detail and brevity, no rambling and no shortcuts, and a quick visit to momentumstructure kept that going across the related pages, the kind of place that respects your attention without trying to grab it through cheap tactics or attention seeking design choices that get tired fast.
Stayed longer than planned because each section earned the next, and a look at trustedalliancenet kept that pulling effect going across more pages, the kind of subtle pull that good writing exerts on attention is something I find harder and harder to resist when I encounter it on the open web today.
Quietly impressive in a way that does not announce itself, and a stop at strategyhub extended that quiet impressiveness, the kind of quality that emerges through sustained attention rather than first impressions is the kind I trust more deeply and this site has been earning that deeper trust across multiple sessions over time consistently.
Worth a slow read rather than the fast scan I usually default to, and a look at ideamapper earned the same slower pace from me, content that resets my reading speed downward is content with substance worth absorbing and this site has produced that effect on me multiple times now over the last week here.
Started reading skeptically because the headline seemed overconfident, and the post earned the headline by the end, and a look at strategyprogression continued that pattern of earning its claims, sites that can back up their headlines without overpromising are rare and this one has clearly developed editorial calibration on that front consistently.
Top quality material, deserves more attention than it probably gets, and a look at actiondrivenprogress reflected the same effort across the site, a hidden gem in the modern web where most attention goes to whoever shouts loudest rather than whoever actually delivers the best content for their readers without much marketing fanfare.
Reading this prompted me to dig out an old reference book related to the topic, and a stop at longtermvaluebond extended that connection to other sources, content that connects me back to my own existing knowledge rather than asking me to forget it is content with continuity and this site has that continuous quality.
More substantial than most of what I find searching for this topic online, and a stop at bondedcapitalpartners kept that quality consistent, this is one of those sites where the writing actually rewards careful reading rather than punishing the patient reader with empty filler stretched out across long paragraphs that say very little.
Looking at this objectively the editorial quality is hard to deny even setting aside personal taste, and a stop at forwardmotionengine maintained the same objective quality, the gap between what I personally enjoy and what is objectively well crafted exists and this site clears both bars simultaneously which is rarer than it sounds.
Reading this triggered a small but real correction in something I had assumed, and a stop at bondedstrength extended that corrective effect, content that updates my beliefs through evidence rather than rhetoric is content with intellectual integrity and this site has earned that label consistently across the pieces I have read so far today.
Started taking notes about halfway through because the points were stacking up, and a look at progressblueprint added enough material that my notes file grew further, content that demands note taking from a passive reader is content with substance and the writers here are clearly producing that kind of work consistently across topics.
Reading this prompted me to clean up some old notes related to the topic, and a stop at strategicconnectionbond extended that organising urge, content that triggers personal organisation rather than just consuming attention is content with motivating energy and this site has the kind of clarity that prompts active follow up rather than passive consumption.
Now wishing more sites covered topics with this level of care, and a look at signalactivatesgrowth extended that wish across more subjects, the rarity of careful coverage on most topics is a problem and this site is one of the small antidotes to that broader pattern of casual or surface treatment of complex subjects.
The whole experience of reading this was pleasant from start to finish, no pop ups and no annoying interruptions, and a look at signalfeedsmomentum continued that clean experience, technical choices about page design matter for the reader and this site clearly cares about the small details that add up to comfort across multiple visits.
Came here from a search and stayed for the side links because they were that interesting, and a stop at directionalintelligence took me even further into the site, the kind of organic exploration that good content invites is something most sites kill through aggressive interlinking and pushy navigation choices rather than relying on quality.
Now feeling the small relief of finding writing that does not condescend, and a stop at actionpathfinder extended that respect for readers, content that treats its audience as capable adults rather than as people to be managed produces a different reading experience and this site has clearly chosen the respectful approach across all pieces.