Monday, March 19, 2012

Jupiter and Io

The image above depicts Jupiter and its moon, Io. The tiny red dot on the surface of Io is a volcano, while the blue above it is the volcanic emissions.  According to NASA, "The Io image, taken on March 1st 2007, is an approximately true-color composite taken by the panchromatic Long-Range Reconnaissance Imager (LORRI), with color information provided by the 0.5 µm (“blue”) and 0.9 µm (“methane”) channels of the MVIC."

Since Io 's discovery by Galileo in 1610, it has continuously been both confusing and amazing scientists. First of all, it's larger than our own moon, and is also the most volcanically active object in the solar system. Io is home to volcanoes that erupt liquid sulfur dioxide, and has a molten iron/iron sulfide core due to the immense tidal heating associated with orbiting so closely to Jupiter at roughly 350,000 km. This happens because the gravitational field of Jupiter is so powerful that it squeeze Io, and that the magma inside Io is pushed outside because of the amount of pressure it induces.

The magnetosphere of Jupiter sucks off the dust and gasses emanating from Ionian eruptions at a rate of about 1 tonne per second. It has no magnetic field of its own, but instead has a magnetosphere created by Jupiter's. This is turn induces an electrical current along the magnetic lines of force from Jupiter's north pole, through Io, and back to Jupiter's south pole, which in turn creates an auroral glow similar to Earth's aurora. It's orbit is encased in a plasma torus of high-energy radiation and ionized sulfur, sodium, oxygen, and chlorine. Io's orbit is eccentric, since Io has the moons Europa, Ganymede, and Callisto pulling it back.

Thursday, March 15, 2012

Happy (Belated) Pi Day!

Yesterday was "National Pi Day" -- March 14 (3.14). It has been declared by the U.S. House of Representatives as a way to introduce children and adults to the wonders of math and science (HR 224, in 2009). Pi is one of the most widely used mathematical constants in science and engineering, but only a relatively small fraction of the general public knows of its significance (perhaps beyond the circumference of a circle being pi times its diameter).

In honor of Pi day, I thought I'd introduce you to a website dedicated to your favorite mathematical concept: Pi! The wife of one of my favorite professors at Cal, Alex Filippenko, created a website designed an educational and entertaining website,, in order to promote National Pi Day as a day to celebrate the fun facts, trivia, and uses of pi.

From an email I received from Alex:

The site has various videos, interactive games, and even pi-related t-shirts –- everything a person needs to celebrate pi. Moreover, you can enter to win an iPad (whichshe calls a "Pi-Pad") or t-shirts; click on the "Play" button, or "like" piZone on Facebook. (No purchase is necessary to win.)

The website is her social mission, and it was created as a crowd-source resource. Under the "pi it forward" program, $3.14 from every t-shirt sale goes to provide a pi-related t-shirt to a K-12 teacher.

I invite you to visit the website or Facebook (piZone) and help share the pi.

Check out the site, it's pretty pi-tastic! And, because I can't resist, in honor of Pi day, my favorite Pi riddle:
Question: What do you get if you divide the circumference of a jack-o-lantern by its diameter?
Answer: Pumpkin Pi!

Monday, March 12, 2012

Introducing TED-Ed:

TED Talks is rolling out their new program: TED-Ed. This is set to be a series of TED Talks, under ten minutes in length, whose intention is to potentially rival Khan Academy.

I think the idea is fabulous, and the more well funded, educational services out there and accessible by students, the better. From the video description: TED-Ed's mission is to capture and amplify the voices of great educators around the world. We do this by pairing extraordinary educators with talented animators to produce a new library of curiosity-igniting videos.

In fact, they make it simple for you to nominate a teacher or animator. This can be done here.

Monday, March 5, 2012

The Most Astounding Fact

Neil DeGrasse Tyson was asked by a reader of TIME magazine, "What is the most astounding fact you can share with us about the Universe?" This is his video response, an incredible and humbling take on the universe: