Axial tilt: a comparison of the winter and summer solstices.
Mitosis under a fluorescence microscope.
A perfect game of Snake.
-RSB
The Monty Hall Problem
December 2nd, 2015 | Brain
The Monty Hall Problem is a famous statistical brain teaser that has caused never-ending debate over the past 30 or 40 years. It is based on the old TV gameshow “Let’s Make A Deal,” which was hosted by Monty Hall, and it goes something like this:
There are 3 doors. Behind 1 door is a fancy car, and behind the other two doors are goats. You first make a choice of one of the three doors. Then Monty Hall open up one of the remaining doors with a goat behind it and then asks you if you want to switch your guess to the remaining door or keep with your originally guessed door. So the question is: should you switch?
The answer is not very intuitive and sort of messes with most people’s basic understanding of statistics.
Here’s the quick answer: YOU SHOULD ALWAYS SWITCH!
Here’s the longer explanation:
The door you originally picked has a 1/3 chance of having the car both before and after Monty gets involved. When Monty picks one of the remaining doors to open with a goat behind it, that doesn’t change the statistics of the scenario. Crazy, right!?
So that means there is a 2/3 chance that the two doors you did not pick have the car. From those two, Monty eliminates a bad door. The remaining unpicked door still has a 2/3 chance of having the car, even though you are staring at just two unopened doors. That’s higher than 1/3, so you switch.
Most people forget the the host knows where the goats are. If you pick door 1, you have a 33% chance of getting it correct and a 66% chance of being wrong. Essentially what you’re being offered at the 2nd part is that if there is a car behind either of the doors you didn’t pick you win. Which is 66%.
Here’s the 3 possible scenarios that can be played to make it even more clear:
You pick door 1. The car is behind door 1. The host opens a door with a goat behind it (either door 2 or 3, since they both have goats).
You switch, you lose.
You stay put,you win.
2)
You pick door 1. The car is behind door 2. The host opens a door with a goat behind it (thus has to be door 3, since the car is behind 2, and you’ve chosen door 1)
You switch, you win.
You stay put, you lose.
You pick door 1. The car is behind door 3. The host opens a door with a goat behind it (thus has to be door 2, since the car is behind 3, and you’ve chosen door 1)
You switch, you win.
You stay put, you lose.
Switching = 66% success rate
Sticking = 33% success rate
If you are still not convinced, you can play around the the odds at this online simulation
http://www.montyhallsimulation.com/
-RSB
Saturn V Cutaway by Stephen Biesty
November 24th, 2015 | Space
(Click to enlarge)
The Saturn V was a NASA rocket used between 1966 and 1973. It is the only launch vehicle that has been able to transport humans beyond low Earth orbit, making it responsible for bringing 24 different astronauts to the Moon.
I love these sort of infographics because they give you a sense of the design and engineering that went into these colossal machines. This illustration comes from a Stephen Biesty Incredible Cross-Sections
book. Looking through these books is giving me a strong rush of nostalgia for the countless hours spent in my youth pouring over all of these intricate details.
-RSB
New Martian Spacesuit Revealed
November 11th, 2015 | Space
NASA recently released a new prototype spacesuit for future Martian exploration. The Z-2 design can effectively “dock” with a Mars rover or with some sort of habitation placed on the surface.
buy xenical online https://www.sanjeevanam.com/products/wp-content/languages/new/xenical.html no prescription
A little like this:
A major advantage of this sort of design is that you can keep the Martian dirt on the outside and never track it through an airlock.
Of course, this design will likely go through many more iterations in the next two decades leading up to launch.
buy cialis oral jelly online https://www.sanjeevanam.com/products/wp-content/languages/new/cialis-oral-jelly.html no prescription
If you want to get involved, NASA is looking for new astronauts! The job application opens in December, 2015. You need to have at least a bachelor’s degree in Science, Engineering, or Math with a few years of experience in those fields. Best of luck!
-RSB
Biisuke Ball’s Big Adventure
October 28th, 2015 | Robot
Rube Goldberg machines are all about taking as many steps as possible to do something really simple. In this clip from the Japanese educational television program, PythagoraSwitch, a small red ball called Biisuke travels through a Rube Goldberg machine to rescue his yellow and green-colored brothers from the ball prison. It’s a pretty neat idea to turn the classic RG machine into an epic quest.
You can find more small machines on the program’s YouTube page.
-RSB
[via Colossal]
Namib Dessert via the ESA Satellite
October 12th, 2015 | Space
Fire & Ice… The red hue comes from the iron oxide which is plentiful in this area of the Namib dessert of Namibia. BUT, the colors are not quite realistic. This is one of the European Space Agency satellite photos that have been recolored as part of an art/science collaborative exhibition called Spaceship Earth.
Here the location via Google maps if you are curious: link.
And here a few more of my favorite images from taken from ESA satellite:
Ganges’ Delta
Peruvian Landscape
Agricultural crops in Aragon and Catalonia
-RSB