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Peter Edenist
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Help keep Arecibo Observatory funded

Arecibo Observatory has been facing funding problems for many years. Now the National Science Foundation are preparing an "Environmental Impact Statement", which is lawyer-speak for "how should we proceed ?". Options range from keeping everything as it is to full site closure. Although a decision is not likely until sometime next year, official public consultation lasts only until June 23rd this year. So this is your chance to have your say in Arecibo's future.

If you simply want to express your support for Arecibo and don't wish to commit to any specific option under consideration, please consider signing the poll linked below. If you want to be more vocal or prefer some specific funding model, you send the NSF an e-mail or even write them a letter, if anyone remembers what those funny "envelopes" thingys are. Instructions are here : https://www.federalregister.gov/articles/2016/05/23/2016-12036/notice-of-intent-to-prepare-an-environmental-impact-statement-and-initiate-section-106-consultation

If you aren't sure if Arecibo should continue receiving funding or just want more information about the situation, you can read my personal experiences with the Observatory at the following link. A suggested generic show of support message is included for those who wish to write to the NSF; feel free to modify it as appropriate.
http://astrorhysy.blogspot.cz/2016/06/just-give-them-some-money-already.html

The short version of the above article is that Arecibo is very far from being outdated, nor is it likely to be surpassed in the next decade or two. Arecibo is an extremely mature facility - rather than being outdated, it's more capable now than it ever was before. It's had many upgrades since its construction in 1963; new discoveries are still resulting from the last one in 2004, and more upgrades could improve it still further. There is no other facility planned that could fully supersede Arecibo save perhaps the Square Kilometre Array, which is unlikely to be operational for the next 15 years (and if you're American and worry about these things, the US isn't playing much of a role in that). Even that will not necessarily reproduce, let alone exceed, all of Arecibo's capabilities. Arecibo requires a relatively modest amount of funding for a unique and diverse range of scientific outputs.

Some projects which depend on Arecibo :
ALFALFA - a large-area survey of neutral hydrogen that's catalogued over 15,000 galaxies to date
http://egg.astro.cornell.edu/index.php/
(see those galaxies here : https://www.youtube.com/watch?v=_t7Pbl-YU4k)

GALFA-HI - a project to map the hydrogen in the Milky Way with exquisite sensitivity and resolution :
https://sites.google.com/site/galfahi/

PALFA - detection and measuring pulsars and the mysterious fast radio bursts :
http://www2.naic.edu/alfa/pulsar/
Arecibo was essential in the 1993 Nobel Prize thanks to the discovery of the first binary pulsar, which provided the first good evidence that gravitational waves exist.

AGES - a deeper survey of hydrogen than ALFALFA over a smaller area, which has discovered starless hydrogen clouds and giant streams :
http://www.naic.edu/~ages/

GALFACTS - measuring the magnetic field of the Milky Way :
http://www.ucalgary.ca/ras/GALFACTS

NanoGrav - a multi-telescope project (of which Arecibo is an essential part) to use pulsars to directly measure gravitational waves that instruments like LIGO cannot :
http://nanograv.org/

Not a specific project but let's not forget the planetary radar (one of only two such systems in the world) that also measures small bodies in the Solar System (e.g. asteroids) which helps determine (among many other things) whether they're likely to hit us or not :
http://www.naic.edu/~pradar/

And it also looks for aliens :
https://en.wikipedia.org/wiki/SERENDIP

What more can you ask of a radio telescope ?

Thanks to +Lacerant Plainer and +Peter Edenist for permission to post this here, I know this is at least as much about politics as science.
We the people ask the federal government to Call on Congress to act on an issue: The Arecibo Observatory in PR is in danger of being closed or severely impaired, take action to keep it well funded. Created by E.D. on May 27, 2016. Sign This Petition. Needs 94642 signatures by June 26, ...
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Community Policy (MODS only!)  - 
 
Calling for mods  : Some members have spoken about the increase in spam in the community. We recognize it is a problem, and the only way to manage it is that each of our members report such posts.

We also want to expand our mods community. Mods need to login in at least twice daily and remove spam and ban such members who post porn or irrelevant stuff. If you wish to help, please apply in the comments.

Ours is a very strictly run community, so all members have to follow the tight posting guidelines. It's easy to make a difference, so please help us keep this community clean and high quality.

Thanks
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I would be happy to help. I don't really post often as I'm really just a browser of articles that interest me. My science interests are mostly chemistry, physics, computer science, genetics, mathematics, engineering and robotics. I have had modding experience before and am happy to help this community out.
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My colleague +Sophia Yang is featured by Boeing for her awesome work on +HRL Laboratories, LLC microlattices in my group. Nice job Sophia! 
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My pleasure:) I found it particularly cool :)
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One of the Best Science Communities on G+

Actually, it's almost certainly the best, and a lot of that has to do with the fact that it is extremely well moderated by the owner +Lacerant Plainer  and his team.  Virtually no spam, discussions are reasonable and knowledgeable, trolls really aren't tolerated, and tons of great Categories for reference.  

Highly recommended!
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Conjunction The University - Episode 3: The story moves forward as Ted and Mary have to make a decision.

Sunday posting for those who are following the story! Hope you enjoy this episode as much as you liked the earlier ones :)

#saturdayscences #sciencefiction #scifi  
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One of the few telescopes left in the Southern hemisphere. We need them! h/t +Charles Strebor and +Ted Ewen.
 
Save the Mopra Telescope & Map the Milky Way

We have spent the last four years mapping the Southern portion of our Milky Way Galaxy with the Mopra Radio Telescope in Australia. However, due to drastic budget cuts the telescope will be shut down at the end of September, leaving our map unfinished and our knowledge incomplete. Help us finish the survey and make it public, so that we can put the Milky Way on the map

#TeamMopra #Science   #Kickstarter  
Catherine Braiding is raising funds for #TeamMopra - Save the Mopra Telescope & Map the Milky Way on Kickstarter! Come and join us on a voyage of interstellar exploration as we chart the least known part of the Milky Way – its Delta Quadrant.
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+Jonah Miller explains general relativity....
 
General Relativity is the Dynamics of Distance

This is part two in a many-part series on general relativity. Last time, I described how Galileo almost discovered general relativity. In particular, I told you that gravity isn’t a force. In fact, gravity is the same as acceleration. Now, this is a completely crazy idea. After all, we’re all sitting in the gravitational field of the Earth right now, but we don’t feel like we’re moving, let alone accelerating. But let’s take this crazy idea at face value and see where it leads us.

(To read this post in blog form, go here: http://www.thephysicsmill.com/2015/08/03/general-relativity-is-the-dynamics-of-distance/)

(If you haven’t read my previous post on why gravity is acceleration, I recommend you do so now. It is here: http://www.thephysicsmill.com/2015/07/26/galileo-almost-discovered-general-relativity/)

But first, we need to make a brief detour  and discuss the Doppler effect.

The Doppler Effect

The Doppler effect is a bit complicated (especially for light), so I won’t go into too much depth. Instead, I’ll describe it by analogy. (I’ve given the same analogy before, in my article on the expanding universe. So if you remember, you can skip all this. See: http://www.thephysicsmill.com/2013/03/24/receding-horizons-dark-energy-and-the-expanding-universe/)

Imagine that Paul Dirac [1] and Leopold Kronecker [2] are playing catch, as in figure 2. Each second, Kronecker throws a ball to Dirac, who catches it. Thus, the frequency of balls that Dirac catches is 1 Hertz (Hz)—one per second, or one inverse second.

But now imagine that Dirac starts backing away from Kronecker, as shown in figure 3. Kronecker continues to throw at a rate of one ball per second. However, since Dirac is moving away from the balls, each one takes longer to get to him. Thus, he catches the balls at a rate slower than one per second…say, one every 1.5 seconds.

A similar thing happens with both light and sound. (In the case of sound, we call it the acoustic Doppler effect [3].) Light is a wave. It has peaks and troughs which wiggle up and down in time, as shown in figure 4. The number of peaks (or troughs) per meter is called the wave number.  The speed at which it wiggles up and down in time is called the frequency. The two are related by the speed of the light wave, which is always constant (see: http://www.thephysicsmill.com/2012/11/19/the-speed-of-light-is-constan/), so they’re basically interchange-able.

The frequency of a light wave is analogous to the frequency at which Kronecker throws balls at Dirac. Instead of counting the number of times Dirac throws the ball, we count the peaks of the wave. The frequency of a light wave also determines its color; high frequencies are blue, while low frequencies are red.

This means that if Kronecker fires a green laser at Dirac, and Dirac moves away from him, the laser light will appear more reddish to Dirac than it does to Kronecker. This is called a redshift. If Dirac were moving away from from Kronecker at an increasing rate, in other words if Dirac were accelerating, the redshift would be even more pronounced.

Gravitational Redshift

So what does all this have to do with gravity? Well remember, gravity is acceleration. So we should be able to see a Doppler-like effect just by moving from a region with strong gravity into a region with weak gravity, or vice-versa. To see what I mean, imagine that Kronecker and Dirac are up to their old tricks. But this time, imagine that Kronecker is on Earth, and Dirac is in space, as shown in figure 5.

Kronecker fires a green laser up at Dirac. Now, remember: gravity is acceleration. Both Kronecker and Dirac are in a gravitational field, so they’re both accelerating. But Kronecker is in a stronger field, so he’s accelerating more. This means that, from Dirac’s perspective, Kronecker is accelerating away from him. Therefore, by the time the light reaches Dirac, he sees it redshifted because of the Doppler effect.

In the context of general relativity, we call this gravitational redshift, and it’s a real effect. We need to take it into account when we read signals sent to us from gps satellites, for example [4].

Redshift, Distance, Time

The peaks and troughs of light make it an extraordinarily good ruler. If you know the wave number of a wave of light, you can count the number of peaks and in the wave between two places and calculate how far away those two places are from each other. In a very real sense, distance is defined by this procedure [5].

How, then, do we interpret the redshifted light that Dirac sees? If light on Earth is redshifted when it goes into space, that light stretches out. The distance between adjacent peaks in the light wave grows. Does this mean that distance itself grows?

Yes. It means exactly that.

In a strong gravitational field, distances are shorter than in a weak gravitational field. Indeed, because the wave number of a wave and the frequency of a wave are interchange-able, this also means that times are longer in duration a strong gravitational field than in a weak gravitational field.

We started with the crazy (but true!) idea that gravity is the same as acceleration. But this has lead us to an even crazier (but still true!) idea: gravity shrinks distance and stretches duration.

This is what people mean when they say that gravity is a warping of space and time (or suggestively, spacetime). The very way that we measure distance is distorted by a gravitational field.

And general relativity is the dynamics of distance.

Next time we’ll talk about how a warped spacetime creates the illusion of a gravitational force.

Further Reading

I took the gravitational redshift argument directly out of the excellent textbook Spacetime and Geometry by +Sean Carroll. If you have a good background in math and you want to learn general relativity, I highly recommend it.  You should also check out his amazing blog: http://preposterousuniverse.com/

Here are some other resources:

1. This is a nice video on the Doppler effect: https://youtu.be/h4OnBYrbCjY

2. The PBS Spacetime Vlog has an excellent series of videos on general relativity. The first two videos cover what I’ve covered so far, but from a different perspective. You can find them here:
https://youtu.be/YycAzdtUIko
https://youtu.be/NblR01hHK6U

References
[1] http://en.wikipedia.org/wiki/Paul_dirac
[2] http://en.wikipedia.org/wiki/Kronecker
[3] http://en.wikipedia.org/wiki/Acoustic_Doppler_effect
[4] https://www.aapt.org/doorway/tgrutalks/Ashby/AshbyTalk5of6.htm
[5] http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf

#Science #Physics #relativity #ScienceEveryDay  
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My pleasure :)
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+Dan Russell is running a search class which has been recommended by +Gary Ray R one of the owners here. It helps to use this to get references and links which are needed by our community.

Dan has mentioned:
"We're running our online class, PowerSearchingWithGoogle.com starting on Feb 8th.  It's a short class (just two weeks) that will teach you new research skills and sharpen up the ones you already have.  It's free--it's online--and if you pass the midterm and final, you'll earn a PowerSearcher certificate!  Register now and start the class next week.  (And if you can't make it on Feb 2, don't worry, we'll be restarting a new class offering every two weeks from now until June, 2016.) " 

Short notice, but it's a good idea for our community.
Search Education Online. Improve your Google search skills with our Power Searching and Advanced Power Searching online courses. Learn tips and tricks to become a fast and effective fact-finder with Power Searching with Google. Deepen your understanding of solving complex research problems using ...
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Finished this course yesterday, and strongly recommend it.
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One last plug before the end! Help us do some amazing science, and get some awesome rewards!
Catherine Braiding is raising funds for #TeamMopra - Save the Mopra Telescope & Map the Milky Way on Kickstarter! Come and join us on a voyage of interstellar exploration as we chart the least known part of the Milky Way – its Delta Quadrant.
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Been some time since someone has commented on our community. We work hard at it. Resharing helps us and the community. Have a great day all!
 
One of the Best Science Communities on G+

Actually, it's almost certainly the best, and a lot of that has to do with the fact that it is extremely well moderated by the owner +Lacerant Plainer  and his team.  Virtually no spam, discussions are reasonable and knowledgeable, trolls really aren't tolerated, and tons of great Categories for reference.  

Highly recommended!
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That would be awesome +Aida Hazlan !
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We are all related : Strange as this sounds, this is the outcome of a scientific search for the human migration using genetic markers. As genetic mutations were observed, the rarer of these were passed down from father to son (Y-chromosomal) and from mother to daughter (mtDNA). Tracing these back led to one tree for men and another for women. And the male line and female line do not converge. Though we are all descended from what is called Y-chromosomal Adam and mtDNA Eve, they did not live at the same time. I'm assuming the other lines just died out. The surprising conclusion? We are all related. We are genetically related.

Our common ancestors : Some 99% of the human genome is shuffled from one birth to the next. The Genographic Project traces the 1% of the genome which is not shuffled—mitochondrial DNA (mtDNA) through the maternal line and the Y-chromosome through the paternal. These jokers in the pack allow geneticists to work back to our common ancestors. Our mtDNA appears to coalesce in a single woman, who lived on the African savannah 150,000 years ago. Our Y-chromosome survives from a single man, who lived in the Rift Valley of Kenya or Tanzania 59,000 years ago. So Adam and Eve did exist—90,000 years apart. The discrepancy is because, unlike the biblical Adam and Eve, this couple only represent the last common Ancestors we can trace genetically.

African Roots : Different populations carry distinct genetic markers. Following the markers through the generations reveals a genetic tree on which today’s many diverse branches can be followed backward to their common African root. The markers still present in our genes allow us to chart ancient human migrations from Africa across the continents. Through these markers, we can see living evidence of an ancient trek to populate the globe.

How Neanderthal are you? : Everyone living outside of Africa today has a small amount of Neanderthal in them, carried as a living relic of these ancient encounters. A team of scientists comparing the full genomes of the two species concluded that most Europeans and Asians have between 1 to 4 percent Neanderthal DNA. Indigenous sub-Saharan Africans have no Neanderthal DNA because their ancestors did not migrate through Eurasia.

Thomas Jefferson was descended from the Middle East : Strange as this sounds, this can actual be proved from the genetic mutation his gene shows. You can read more about it here - http://www.sciencedaily.com/releases/2007/03/070328111115.htm

References and Links

Youtube link to Spencer Well's video : https://www.youtube.com/watch?v=-dDXIX-y6aY

http://www.monticello.org/site/research-and-collections/biographical-identifications

https://genographic.nationalgeographic.com/science-behind/

http://moreintelligentlife.com/content/jm-ledgard/exodus?page=full

https://genographic.nationalgeographic.com/neanderthal/

https://en.wikipedia.org/wiki/Mitochondrial_Eve

http://archiver.rootsweb.ancestry.com/th/read/GENEALOGY-DNA/2005-06/1119997289

Pic courtesy : Natgeo

#science #genetics  
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+Kim Van Kramer asked about her book in the Science Fiction community. While I have not read it yet, it sounds intriguing.

Take a gander!
 
Hello. If there are any sci fi fans here! Enjoy! This book is a near future event about Mars available on Amazon, Nook, and Kindle.
Thanks Peter Endenist for letting me post here. I did the cover art myself using photoshop. I am a designer and a writer. 
http://www.amazon.com/Escape-Phobos-K-Van-Kramer/dp/1609751183/ref=sr_1_1?ie=UTF8&qid=1440510228&sr=8-1&keywords=escape+to+phobos
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Yes all three Thex. ;)
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Circle curator for Science and Science Fiction Circles.

I have over 20 Circles and additional circles in my Pages +Peter's Scifi Page, +Fascination SciFi, +Circles on Google+, Peter Tom.

To support my circles, the best thing you can do is reshare them. Circles are reshared on an average of 25 to 35 days. I notify from time to time during circle shares, but not very often. Once in a while I support some author or artist or cause, in which case I may notify you.

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