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Dean Calahan
Works at Smithsonian Institution
Attended Johns Hopkins: Ph.D. Biology
Lives in Chesapeake Region
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Dean Calahan

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I think a BEAM module would be about the right size to house a space station bathroom. Right now it's just outhouses inside the house!
A NASA astronaut, a Russian cosmonaut, and a...
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+Stephen Doggart Discreetly. They don't bath with a shower but wipe themselves weekly with wet disposable towels. I imagine they have other uses.

Curious about what feels an orgasm is zero G.
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Dean Calahan

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A crow and a heron, roosting in a tree. Oosterpark, Amsterdam.

This came out better than expected. I'm not yet set up to "Print as..." cameo, but perhaps some day.

I have seen trees full of roosting great blue herons, at low tide over the headmuds of a narrow Puget Sound fjord, the intertidal zone covered with algae. Somewhere I have a chemical photo of it. Spooky. Someday I may get all that stuff scanned.
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Rad-hardening is a necessary challenge to overcome for building craft that operate in space. You can't in general just use off-the-shelf components, even redundantly. You might think shielding is the answer, but cosmic ray particles generate secondary radiation that can be even more damaging than the original particle, so shielding can make things worse, unless your mass budget has enough margin to accommodate a couple meters thick of aluminum (note: it doesn't!)
Successful part performance in the space environment requires hardening at the part level as well as thorough characterization and acceptance testing.
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I was taking CDMA spread spectrum training at a Lucent technologies lab in the early 90s and they were working on building a phototronic system at that time. A phototronic systems are supposed to eliminate semi-conductors all together and run systems using photons and not electrons.
Never heard what became of it but just on its face I could see there were some large obstacles to overcome.
As of now shielding and using military grade components more tolerant against thermal saturation are the world's only answer that I am aware of.
Reproducing a magnetic field or surrounding space vehicle in water is being toyed with in theory but haven't seen any earnest work in this direction.
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Dean Calahan

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The Rijksmuseum itself is kind of an exhibit. The last time I was there, over a decade ago, it was being refurbished and they had but one corner open, three floors of their most popular stuff, and they really shuffled you through. Much better now, although the time before that, you could get down in the basement and look in drawers, and page through actual Albrecht Dürer prints - made by himself! - like in the poster section of an old record store.
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Dean Calahan

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Not exactly Space Development. However, my passions are life support (obliquely, see my profile and Biopix collection) and music; this rare (for me) video post combines both my vocation and my avocation.
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A green roof seen in Joellenbeck, Deutschland. Living thatch? One appeal is that if dry they can soak up the first bout of a rain onslaught, reducing downstream impacts. I'd love to see a life-cycle analysis of them.

I think I'd rather go full-scale hobbit hole if I could*, or pick some other infiltration mitigation practice, such as rain barrels**. I don't find green roofs all that attractive from a visual beauty point of view.

*For example, http://www.undergroundhousing.com/book.html

**Of course rain barrels in addition to green roofs would do even better at infiltration mitigation.
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+Todd Henderson great find, thanks!
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I am privileged to be able to watch this live. Elon's Mars Plan. Or as I just started saying yesterday, "Space 2.1".

http://www.spacex.com/webcast
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+Carl Bernstein
He is all of these things you mentioned but the right qualities to save this country I believe. Greed is a human trait and the main driver behind capitalism. Its also the same driver for socialism. Laying on one's back making babies that everyone else has to go hard to work to pay for is no less greedy than a selfish billionaire.
The difference between them is capitalism creates and socialism only takes.
No country or its people have ever become wealthy thru socialism and socialism has yet to prove it works over time anywhere.
Jobs, fiscal budget and a large middle class are the only answer and democrats have never done anything to improve either of these.
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Near the Rijksmuseum. Latin possesses a gravitas that obviates the necessity of ending the sentence with (if even translatable) ", dumbass".

Wow. I just noticed that "dumbass" rhymes with "gravitas".
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It is thought to be medieval Latin. Urinat meant "dive" but switched meaning to "piss", or so I read.
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I love the sight of rocket testing in the morning. It reminds me of Space 2.1.
 
SpaceX test-fires 'Raptor' rocket that will take humans to Mars
https://www.engadget.com/2016/09/26/spacex-raptor-rocket-first-test/

The engine is three times more powerful than the one on the Falcon 9.
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Have joty
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Dean Calahan

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Here, Giuseppe Penone has flensed away the yearly growth layers - what come out as tree rings when you cut through the whole bole, revealing the tree that was. The Rijksmuseum grounds are rife with his stuff, which is not all like this!
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Oo, nice use of "flensed".

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Good
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I'll not trouble you with all the dining enjoyment I had on my recent vacation. However you could do much worse than dine at Les Artists Gourmands, just a few steps from the Voltaire Metro stop, on the Rue de la Roquette. Nice, from small lunch to full supper - pizza, pasta, and (good!) specials.

You can make out the remains of our feast in the right hand window, which was nicely open to the fine air and local shenanigans.
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Dean's Collections
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Work
Occupation
Algae farmer
Skills
Cell & molecular biology, genetics, bioinformatics, software engineering, making things happen
Employment
  • Smithsonian Institution
    Researcher/Fellow, 2013 - present
  • Johns Hopkins
    Ph.D. Biology, 2004 - 2011
  • Towson University
    B.S. Molecular Biology, Biochemistry, and Bioinformatics, 2002 - 2004
  • Microsoft
    SDE/T, 1993 - 2000
  • Aldus
    Test lead, 1987 - 1992
  • Timeline
    Mainframe operator, 1983 - 1986
  • University of Washington
    Chemistry, 1981 - 1985
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Chesapeake Region
Previously
Puget Sound Region - Mid-Willamette Valley
Story
Tagline
Genes, Cells, Informatics, …Algae!
Introduction
Willamette brewed, Puget aged, Chesapeake tapped.

I love reading what you post directly. However, I don't want to see what you've +1'd. Also, please try using Collections for your food and cat pictures.

Have a nice day!
Bragging rights
Walked around Mount Rainier in nine days. Hiked the entire Olympic National Park wilderness coast. Did 4-season camping for many years (Christmas at Panorama Point, Mt. Rainier; Cape Alava, Olympic Coast, in 70 mph winds; etc.).
Education
  • Johns Hopkins: Ph.D. Biology
  • Towson University: B.S. Molecular Biology, Biochemistry, & Bioinformatics
Links
Dean Calahan's +1's are the things they like, agree with, or want to recommend.