The P Versus NP Problem Is One of Computer Science’s Biggest Unsolved Problems
In the world of theoretical computer science, P vs. NP is something of a mythical unicorn. It's become notorious, since it remains an unsolved problem. It basically asks this: If it is easy to check that a solution to a problem is correct, is it also easy to solve that problem? Get back
Retrograde Orbits
(note: This animation has no audio track.) - The Open University Although many moons in the Solar System follow prograde orbits, there are some notable exceptions. The gas giant planets Jupiter, Saturn, Uranus and Neptune have several small outer moons that follow retrograde orbits; this means that they orbit their planet in the opposite direction
Solving the Assessment Puzzle — Open Matters
By Sarah Hansen, OCW Educator Project Manager Assessing students’ learning is one of the most important things we do as educators. It’s also one of the most complicated. There’s a lot to consider: When will assessment happen? (Along the way? At the end of the course?) How will we collect useful information about
Tesla Orbiting Earth
Credit: SpaceX. Explanation: Last week, a Tesla orbited the Earth. The car, created by humans and robots on the Earth, was launched by the SpaceX Company to demonstrate the ability of its Falcon Heavy Rocket to place spacecraft out in the Solar System. Purposely fashioned to be whimsical, the iconic car was thought a
Physical Properties of Minerals
1) What is a mineral? A mineral is a naturally occurring inorganic crystalline substance, whose compositions are either fixed or vary between certain fixed limits. This excludes, for example, artificial diamonds, coal, volcanic glass. What makes each mineral unique is a combination of its chemical composition and the internal arrangement of its constituent atoms. The
A Brief History of the Universe
The universe is the biggest and oldest thing we know. It contains all existing matter and space. And its origin marks the beginning of time as far as we understand it. We don’t know what made the formation of the universe possible, nor why it occurred. The visible universe is currently about 93
Venus and the Triply Ultraviolet Sun
Venus and the Triple Ultraviolet Sun Image Credit: NASA/SDO & the AIA, EVE, and HMI teams; Digital Composition: Peter L. Dove (http://www.flickr.com/photos/pldove/) Explanation: An unusual type of solar eclipse occurred in 2012. Usually, it is the Earth's Moon that eclipses the Sun. That year, most unusually, the planet Venus took a turn. Like a solar
The Structure of the Earth
Physical Properties of the Earth The Earth is an oblate spheroid, being slightly flattened at the poles: Equatorial radius = 6378 km Polar radius = 6357 km These measurements are calculated on the assumption that the Earth's surface is smooth, but this is only an approximation since it disregards mountains and ocean depths. However, the difference between
Insights on Teaching Japanese, in Japanese (and English) — Open Matters
https://www.youtube.com/embed/K12JGiYHcTw?version=3&rel=1&fs=1&autohide=2&showsearch=0&showinfo=1&iv_load_policy=1&wmode=transparent By Joe Pickett, OCW Publication Director OCW has just published 21G.503 Japanese III, the third in a four-course sequence on Japanese taught at MIT. With relatively few Japanese speakers on the MIT campus, the instructors must make the most of what happens in the classroom and motivate students to work hard outside it.
Why Alien Life Would be our Doom – The Great Filter
New video by Kurzgesagt – In a Nutshell. Sharing this as it's very interesting for all to know :) The first 688 people to use this link will get 20% off their annual membership: http://brilliant.org/nutshell Finding alien life on a distant planet would be amazing news - or would it? If we are not the only