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P. McRell
Attends the school of hard knocks
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P. McRell

Discussion  - 
 
Meet the CEO of Elon Musk's 760mph Hyperloop transportation company

Can he really build a supersonic tube transport system, which could go from LA to San Francisco in 35 minutes?
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There is room for both normal rail and hyperloop, in the same way there is need for buses and subway and cars.
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P. McRell

➥ 3D printing  - 
 
VIDEO: TED2015 yesterday showed this "fast grow" 3D technique that looks more like sci-fi than reality when you see the counterintuitive video below...but it actually works and has some profound advantages over existing tech.
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P. McRell

Science News (Pop Sci)  - 
 
NASA's last CTO has a strong opinion on Mars One and its technical/scientific challenges 
Defeatism, cynicism and mindless conservatism didn't get us to the moon, writes Mason A. Peck, an associate professor of engineering at Cornell University and an unpaid adviser to Mars One.
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Better to try and fail than to never even try. I fully support Mars One. The entertainment side is just an ingenious way to fund it, it's not the primary goal of the mission to make a reality TV show. The candidates are going in to this with eyes wide open as to what it means for them and the rest of their lives, and if successful they will go down in history and be remembered forever. Yes there are technical hurdles to overcome, but if we never even try, we will never overcome them will we?
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P. McRell

Space Exploration  - 
 
NASA's last CTO has a strong opinion on Mars One
Defeatism, cynicism and mindless conservatism didn't get us to the moon, writes Mason A. Peck, an associate professor of engineering at Cornell University and an unpaid adviser to Mars One.
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P. McRell's profile photoSean Johansson's profile photoJuan Manuel Grau Lafaurie's profile photoKarim Qaiser's profile photo
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+Sean Johansson How do they resupply those bases with toilet paper? You seem like the kind of guy who is in the know.
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P. McRell

Science News (Pop Sci)  - 
 
Who cares about consumer goods - this is the real threat to Western dominance...
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Matt, no evidence, no respect. The information you have posted could have been generated by a 6th grader whereas we have posted examples of scientific proof. So in regards to rhetoric, that's all you.

Show us why Thorium can't be used as the primary feedstock in a fission reactor as my sources clearly illustrate or we will continue to treat you as an uneducated crank.
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P. McRell

➥ Project/Product photos  - 
 
 
CRYO EXPERIMENTS

As if it itsn't cold enough around here...  may I present the poor man's cryo-cooler.  For this project you will need the following:

Supplies:
Alcohol, the purer the better.  Don't use less than 99% isopropyl 
A tall soda can (16 oz) (a shorter one would probably work fine).
A plastic vessel the soda can fits in but leaves a little room on the sides.
3lbs of dry ice.

Safety gear:
Safety glasses
Insulated gloves
Long pants and long sleeve shirt

Tools:
Toenail cutter
Drill
Hammer
Aluminized mylar blanket "space blanket"

Safety notices:
The alcohol bath gets down to -77F (-60C).  While not as cold as liquid nitrogen, this stuff also doesn't immediately turn to gas when in contact with your skin.  Instead it will cling to your skin like cold napalm continuing to burn until it finally reaches an equilibrium temperature.  

Do not let the chilled alcohol touch your skin and take great pains not to have an accident.  If the alcohol spills on your clothing, remove it without delay.  If you are too slow, it will freeze the article of clothing to you.  If it does, do not attempt to pull hard; you will only succeed in removing a chunk of meat from the affected area on your body.  In any event, seek medical assistance immediately.

Do not breathe the CO2 vapor and do not perform this procedure in an enclosed area.  A buildup of 10% CO2 in an enclosed space can kill you in under 15 minutes.  If you experience headache, sweating, rapid breathing, increased heartbeat, shortness of breath, dizziness, mental depression, visual disturbances or shaking, immediately leave the area where the experiment is happening, alerting any others in the area of your situation.  

Procedure:
After drinking the contents, cut the top off of the soda can with the toenail clippers.  The technique is to place the jaws of the clippers over the crimped edge on the top of the can, then squeeze the lever while moving the non-cutting end of the clippers away from the center of the can.  When it cuts through the aluminum you will hear a soft click.  Work around the top of the can until the whole top comes off.

Rinse the inside of the can to remove any of the original contents and dry thoroughly. Be careful, the cut edge will be razor sharp.  To make it safer, I bend the tapered edge inside the can little by little bending it by hand and working my way around.  Precision is not required.  

Drill several holes in the side of the plastic container at the top and bottom.  Place the can inside the plastic container making sure that there is some room for the air to flow around the can inside the container.  See the drawn illustration.  

We will use the space blanket to wrap the dry ice in for storage.  Unfold it completely, then loosely fold it in half 3-4 times.  This will yield several layers of the material with air layers between, making it very insulative, denying radiation, convection, and conduction as methods of heat transfer.  

Wear long pants and a long sleeve shirt when doing the next steps.  Put on the gloves and eye protection.  Place the dry ice on a solid surface and break it with the hammer into pieces small enough to drop into the can.  If you can, collect the dust that chips off the dry ice and dump that in the can as well.  The can will make some haunted house noises as it contracts from the extreme cold, this is normal.  

Completely fill the can with dry ice chunks.  Place the remainder of the dry ice in the center of the space blanket and wrap it up, keeping the mylar layers fluffy.  Slowly pour the alcohol into the can.  It will cause the dry ice to sublimate into CO2 pretty violently with the characteristic fog.  

DO NOT breathe this.  CO2 is not a breathable gas, and it will contain the isopropyl alcohol in an aerosol.  This would be profoundly bad for and to you, not get you high.  

Keep adding the alcohol until the dry ice is covered in liquid.  You will notice that the alcohol does not freeze, but instead gets thicker.  As it approaches the consistency of thick motor oil you will notice the bubbling begin to calm down.  This is because the alcohol is near the sublimation point of the dry ice, around -77F (-60C).

Use:
At this point you can put the assembly into a cooler, and the convection flow around the can will cool the air inside the cooler.  Just drop a lump of dry ice in occasionally to maintain the temperatures.  I will report the temperatures in the cooler shown over time.

You can also freeze things like flowers or gummy bears by dipping them briefly in the alcohol bath.  These will shatter when dropped or struck with a hammer.  Most cryo experiments will work reasonably well at these temps, but bear in mind that Methanol and isopropyl alcohols are not food safe.  Use pure ethanol for food experiments.

Another good use is to demonstrate the hazards of extreme cold.  Take a hot dog and place it in a work glove finger.  Place this finger in the chilled alcohol for a couple of minutes.  Remove the glove and simulated finger from the bath, shaking off the excess alcohol.  Strike the glove finger against a hard object like a wall or steel hand rail.  If the glove stays together, there will be cracks, but the hot dog will have shattered in the glove, just as a finger would have.
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P. McRell

Science News (Pop Sci)  - 
 
VIDEO: TED2015 yesterday showed this "fast grow" 3D technique that looks more like sci-fi than reality when you see the counterintuitive video below...but it actually works and has some profound advantages over existing tech
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P. McRell

Discussion  - 
 
VIDEO: TED2015 yesterday showed this "fast grow" 3D technique that looks more like sci-fi than reality when you see the counterintuitive video below...but it actually works and has some profound advantages over existing tech.
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P. McRell

Space Exploration  - 
 
Buzz is right: we can get to Mars faster, cheaper; and with more permanence by focusing on one-way missions.
 
Buzz Aldrin showed his support for a permanent human settlement on Mars before the U.S. Senate's Subcommittee on Space, Science and Competitiveness. Check out this interesting article for more information! http://mars.social/pzjqqm - NBC News
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I like Musk's take on this. He's fully planning on sending the Mars Colonial Transporter back to Earth (as it's going to be expensive). Whether people chose to stay or leave on a given trip is their business. :D I think this is too often bill as a permanent one way trip. It could be for some, but then folks could always head back after a number of years working on the colony as well. I suspect once we get into the habit of sending regular supply runs, the costs will come down.
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P. McRell

Discussion  - 
 
NASA's last CTO is concerned that the cynics of the future are winning...
Defeatism, cynicism and mindless conservatism didn't get us to the moon, writes Mason A. Peck, an associate professor of engineering at Cornell University and an unpaid adviser to Mars One.
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Armando OrtizV's profile photofocusontheargument's profile photoMario Radanovic's profile photoSean Homer's profile photo
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Maybe what is needed is a talented public relations guy and propaganda machine. Just like in some countries (excluding those who oppressed their people); actions of their politicians are clear lies, and some were stupid, but they had a very large following.
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P. McRell

General  - 
 
Not a movie set - but the kind of aesthetic 100 people at a time might experience on their way to Mars in the 20's if Elon is successful with Falcon Heavy/MCT/re-usable rockets in the next few years
 
NASA's Next Space Race: SpaceX vs. Boeing ... BELOW: The inside of SpaceX's Dragon V2, designed to take seven crewmembers to space. ... "Two American spaceflight companies are quietly competing in a space race for the new era.

SpaceX and Boeing are vying to become the first private firms to fly astronauts to the International Space Station for NASA sometime in 2017. NASA chose both companies as part of the agency's commercial crew program, which may effectively end NASA's current sole reliance on Russian vehiclesto get astronauts to and from the orbiting outpost. ..."

MORE: http://www.space.com/28411-spacex-boeing-nasa-space-race.html
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Alexander Fretheim's profile photoP. McRell's profile photoFinal Cut Media Productions's profile photoUriel Orozco's profile photo
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O2 will take a very long time because it will be done the way it was on earth - with archaea, but creating a warm atmosphere would only take decades or centuries at the worst.

If you built a 100% sunshade for Venus in the Venus-Sun LaGrange, it would take hundreds of years just to freeze out the atmosphere. The sunshade would have to be 4x the diameter of Venus.

You could build cloud cities, but lack of water and intense radiation would require incredible amounts of mass and that isn't terraforming.

Either way, days and nights last for almost 4 months on Venus and that will require asteroid bombardment to speed up rotation on a scale beyond anything practical in our foreseeable future.

Mars just needs its nominal atmosphere heated by 5C and you are off to the races. It's trivial in comparison.


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P. McRell

Space Exploration  - 
 
Exploration has always been dangerous and controversial. I doubt we'll ever live in a society where high risk endeavors, even those critical for our species, don't attract critics.
 
Another exciting Mars Exchange article has been released! Mason Peck, PhD, who served as NASA’s Chief Technologist, discusses whether broadcasting the human mission to Mars as entertainment opens up moral risks. http://mars.social/cq3d4o - Mars Exchange
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