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Dr. Jay Maron, physicist
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Technology Space Megaprojects Bubbles
Solar cells Rockets Colossal colliders Colleges
Wind turbines Spaceship design Skyscrapers
Electric cars Manned Mars mission American football
Flying_cars Fission fragment rocket Natural disaster defense NCAA
Neutralizing nuclear waste Fusion rocket Icebergs for freshwater
Superconductors Stratosphere rocket launch Global warming hysteria
Nuclear transmutation Orbital launch sled Antarctic wind power The UFC
Thorium nuclear power L2 telescope farm Asteroid mining Power leagues
Fertilizer Terraforming Mars Asteroid defense Patents
Biochar Square km radio telescope Iron fertilizer for carbon sequesterization The Common Core
Lasers Antarctic telescopes Great Americans Brackets and pools
Xenon anaesthetic Black hole reactor Great American Things 3 Gorges Dam
Synthetic diamond and sapphire Keystone pipeline Physical Therapy
Fullerines Stopping Antarctic ice Optometry
Solar powered aircraft Neutron farm American Medical Association
Technologically-critical elements Textbook price gouging
Political correctness
Kalpasar estuary dam Pharmaceutical price gouging

Planet X

A Neptune-sized planet has been hypothesized to exist at a distance of 20 times Neptune's distance. To estimate the brightness of this planet,

Planet X flux    =   Neptune flux * (Planet X radius / Neptune radius)2 * (Neptune distance / Planet X distance)4
                 =  1.6e-11 Watts/meter2 * (1/1)2 * (1/20)4
                 =  1.6e-16 Watts/meter2
Pan-STARRS limit =  5.0e-18 Watts/meter2
Planet X speed   =       86 arcseconds/year          (for a 15000 year orbit)
Pan-STARRS does a full sky survey every month. If Planet X existed, Pan-STARRS would have seen it, and it would have stood out for its proper motion.
Aircraft safety

Suppose you use a parachute to land a disabled aircraft. The aircraft can decrease its mass by ejecting fuel and engines. There's little point to ejecting the wings because they are lightweight and have a large cross section.

For an Airbus A380,

Empty mass             =  270 tons
Max unfueled mass      =  369 tons    with passengers and without fuel
Max passenger mass     =   99 tons
Wing mass              =   60 tons    Both wings
Engine mass            =   27 tons    4 engines at 6.7 tons each
Max takeoff mass       =  575 tons
Max landing mass       =  394 tons
Typical fuel mass      =  146 tons
Max fuel mass          =  320 tons
Crash mass             =  429 tons    Fuselage + wings + passengers.  No fuel or engines
Fuselage width         = 7.14 meters
Fuselage height        = 8.41 meters
Fuselage length        = 72.7 meters
Fuselage area          =  500 meters2          as viewed from above
Wing area              =  845 meters2
Total area             = 1345 meters2
Air density        = D = 1.22 tons/meter3     at sea level
Drag coefficient   = C =  1.0 for wings                 for falling vertically
Velocity           = V = (2Mg/A/C/D)½    Falling velocity when gravity = air drag
Aircraft mass      = M
Gravity constant   = g =  9.8 meters/second2
Gravity force      = Fg=  M g
Cross-section      = A
Drag force         = Fd= .5 C D A V2
Wing terminal V        =   34 meters/second
Aircraft terminal V    =   71 meters/second
Personal parachute     =  1.5 kg                  Up to 100 kg load
Personal parachute     =  6.2 meters/second       Descent rate
Personal parachute     =   23 meters2


The Martian: Mars max wind ~50 m/s. Earth wind speed with equiv force ~50 m/s *(MarsAirDensity/EarthAirDensity)^.5 ~6 m/s. Not a hurricane

Ceres max mountain height ~ Earth max height * Earthgrav / Ceresgrav * Icetensile / RockTensile ~ 10 km * 9.8 / .29 * 1 MPa / 25 MPa ~ 14 km

Bafflingly, the unit of "Action" = Joule seconds hasn't been given a name. Propositions?

University of Chicago



The news site that ranks number one in facebook shares and likes is Breitbart, in spite of the fact that Facebook aggresively censors Breitbart activity from newsfeeds, including the news that Facebook censors Breitbart.

Ben Askren

Dana White, Luis Santos

A UFC contract: Gives exclusive rights to the fighter's likeness to Forbid fighters from promoting themselves.

The UFC requires an army of lawyers

Tim Canova

Debbie Wasserman Schultz


Milo Yiannopoulos

Milo's "Dangerous Faggot Tour" of universities has been a fine piece of trolling, exposing the pettiness of the PC zombies.

U.C. Irvine


Ann Coulter

Coulter's book "Adios America" prophesized the

Donald Trump

Megyn Kelly

Bernie Sanders

Hillary Clinton

Megan Warren

Harvard study

Political Correctness

Rand Paul

You were the chosen one! It was said that you would destroy the Republican party, not join it!


Against all opposition, Breitbart triumphed and now owns the political arena.

The liberal media

Emma Sulkowicz

It has been overwhelmingly established through emails, screenshots, interviews, etc. that:
*) Sulkowicz was on amorous terms with Nugesser for at least a month after the alleged incident. *) Sulkowicz conspired to have 3 accomplices file complaints against Nungesser, none of which contained evidence and all of which were found to be fraudulent.

Sulkowicz perseveres with her evil. She continues to act as though she had been honest.

Tim Hunt

Connie St. Lewis


Barack Obama

One should be wary against the unnecessary centralization of power. The president's powers should be the minimum necessary for the common good and power should be made as local as possible.

Megyn Kelly

Refereeing is an art. The quality of a debate hinges on the quality of the moderator.

Trump has commented that he wants journalists to be critical but fair.

The Republican and Democratic parties

Megyn Kelly

The Paris Agreement

Megyn Kelly

Emory University and The Chalkening

Berkeley special snowflakes

Berkeley Adjunct Professors

Apple Corporation

Google Corporation

Marvin Krislov

Oberlin special snowflakes

Yale special snowflakes

Marshawn Lynch

Pete Carroll

Should have given Marshawn Lynch the ball.

Ken Griffey Jr.

Barry Bonds

Harvard special snowflakes

Linus Torvalds

Matt Taylor

Witchhunt mobs

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