Author: Lensyl Urbano

The Galilean moons of Jupiter

Io over Jupiter taken by NASA's Cassini spacecraft.

400 years ago, on January 7th, Galileo Galilei made his first observations of Jupiter. You can see his notes below. The big circle is Jupiter and the small dots are the specks of light he observed adjacent to the planet. Later observations showed that the specks did not stay in the same place, and lead him to realize that he was seeing moons orbiting the planet.

Galileo's notes from Jan 7, 1610.
Translation of Galileo's notes (from NASA).

Galileo used a 33x telescope, which is pretty weak by modern standards, in fact you should be able to see Jupiter and it’s moons with a good pair of binoculars. Since the Catholic church at the time preferred the view that the Earth was the center of the universe, when Galileo published his observation he got into a bit of trouble. In his publication Galileo wrote:

On the 7th day of January in the present year, 1610, in the first hour of the following night, when I was viewing the constellations of the heavons through a telescope, the planet Jupiter presented itself to my view, and as I had prepared for myself a very excellent instrument, I noticed a circumstance which I had never been able to notice before, namely that three little stars, small but very bright, were near the planet; and although I believed them to belong to a number of the fixed stars, yet they made me somewhat wonder, because they seemed to be arranged exactly in a straight line, parallel to the ecliptic, and to be brighter than the rest of the stars, equal to them in magnitude . . .When on January 8th, led by some fatality, I turned again to look at the same part of the heavens, I found a very different state of things, for there were three little stars all west of Jupiter, and nearer together than on the previous night.

The above quote comes NASA’s page on the discovery of the Galilean satellites (for a full translation of the entire document go to: The Starry Messenger). The NASA page also has another neat quote, from Simon Marius describing how the moons got their names:

Jupiter is much blamed by the poets on account of his irregular loves. Three maidens are especially mentioned as having been clandestinely courted by Jupiter with success. Io, daughter of the River, Inachus, Callisto of Lycaon, Europa of Agenor. Then there was Ganymede, the handsome son of King Tros, whom Jupiter, having taken the form of an eagle, transported to heaven on his back …

For perspective, the image below, of Io’s surface, was taken by NASA’s Galileo spacecraft. Click on the image to get to the high resolution version.

Closeup of Io
Closeup of Io's surface.

The Galileo Mission website is a great resource about the mission to Jupiter and about Galileo Galilei himself. You can also find out what NASA’s up to with respect to Jupiter here.

Artists sit to the right

With open classrooms allowing lots of movement, we don’t often have to deal with issues of seating arrangements. But, an interesting study (from back in 1993) found that students (adults in this case) who sit on the right side of the room are more right-brain oriented. They tend to be more the artistic types, less cautious in responding and less analytical. Right side sitters also scored higher on femininity on a Masculine-Feminine scale.

Since we’re creatures of habit, I wonder if we can see this pattern in the seating arrangements for lessons and community meetings. On balance though, I’d think this would be another argument (if another was necessary) for allowing students and lots of movement so there is more mixing and sharing of talents.

This seating pattern preference also shows up in where people prefer to sit in movie theaters.

Evil, mad, scientist!

Why have I not found this site before, Evil Mad Scientist Laboratories. A place where people will put serious thought, rigorous design and atrocious single-mindedness to create, well I’m not sure I can call it anything other than, “very interesting” projects. Applications of robotics that would make Asimov cry (probably with joy at human ingenuity, probably).

They carefully detail how to create such wonderful projects as:

And many more interesting and eclectic projects for an interesting middle school.

A sense of justice as a key to moral development

On an personal level, I’ve always felt that the sense of justice shapes the way people react to the world on a fundamental level. In the language of Montessori, justice is a fundamental need of humanity. As we mature we begin to see justice from different perspectives, and after going over the history of human rights, I wonder if this applies to societies as well.

Lawrence Kohlberg’s famous theory about the stages of moral development center around the idea of how people see and react to justice and injustice. His first level (pre-conventional) is based on how moral actions affect oneself; if I do this then they will do that right back to me (and I won’t like it). In the second level (conventional) the main concern is how actions affect and are perceived by society; it’s not right to do this because everyone will talk about it (and I don’t like that). The final level (post-conventional), moral judgments are made based on some underlying principles; I should not do this because it will violate someone’s universal human rights (and I would have violated my own principles).

When we talk about the history of human rights, we are discussing how society has gone through these different stages. The first rule of justice, no matter the culture, is some variant of the Golden Rule, an eye for an eye. Eventually we discover the rights of the citizen, then finally the rights of humans. In humans, this moral evolution is innate in potential but not necessarily realized. Similarly is societies, after all, the Greek democracies eventually failed. But there seems to be a general trajectory of history toward post-conventional morality. Robert Wright, in his book “Nonzero” sees this path as the almost inevitable outcome of the beneficial nature of cooperation to human societies.

Of course Nonzero was written in the post-Cold War and pre 9/11 period, when the world was breathing a sigh of relief when the potential for global thermonuclear war seemed to disappear (I also remember David Rudder’s 1990 had a similar theme).

Two faced

Facial symmetry: left=original picture; middle=left-left composite; right=right-right composite

A slight tilt of the face to the left or the right changes the emotional message you send. There’s a whole field of study on what’s called laterality that looks at how the asymmetry of your posture says things you might not realize.

Mike Nicholls has done some interesting work. In one study, he took two pictures of just the left side of peoples’ faces and reflected one half to make a composite image that basically had just two left sides or two right sides. The image above (which was not done by Nichols) shows an original photo, a left-left composite and a right-right composite. He found that:

… head turns of just 15 degrees can bring about significant changes in the perceived emotionality.

Nicholls discusses the implications with regards to the fact that portraits tend to feature the left side of the face. However, it is also interesting to think about what this means for non-verbal communication. Another paper, using 3D imaging of facial movements showed that:

Emotions are expressed more clearly on the left side of the face than the right … There was a trend, however, for left-sided movement to be more pronounced for negative than positive emotions.

Uganda and the human rights of gays

Uganda

These last few weeks we’ve been talking about human rights, and today I heard a poignant article on NPR about the anti-homosexual bill being debated in Uganda. It touches on so many of the rights issues we’ve been discussing in class and more. Incitement by American evangelical pastors, whose invective against homosexuality is subsumed by the more tolerant US culture, can sow viscous seeds of hatred in a less liberal society. The Ugandan law being debated would increase the institutionalized discrimination to the point of including execution for gays and prison sentences for people who do not inform on them.

But the article also addresses Ugandans’ instinctive animosity against colonialism. Since homophobia has taken an important place in the Christian mythology of Uganda (in 1886 two dozen Christian palace pages were executed for not engaging in homosexual acts with the king). When foreigners (NGO’s and liberal governments) say homophobia is a violation of peoples’ human rights, the Christian Ugandan proponents of the bill claim cultural imperialism and colonialism. Note the phrase “Christian Ugandan” and consider the irony.

As an added bonus, there’s also Rick Warren, the American mega-church pastor, quoting Edmond Burke, “All that is necessary for evil to triumph is for good men to do nothing” in his late-in-coming but nice to hear condemnation of the bill. It raises the question of moral conflict, as sincere opponents of gay rights see their works taken to their scary extreme.

Adolescents often need help to realize that words have power, sometimes much more than you realize.

Though it’s not emphasized, the article also has a lesson on checks and balances in a democratic government; the Ugandan president now opposes the bill. It also teaches about international relations and the power of diplomacy. Sweden has said it will cut international aid to Uganda and the issue is overtaking other international issues. The BBC article on the topic has a great quote from President Museveni:

“The prime minister of Canada came to see me and what was he talking about? Gays,” he said.

“[UK] Prime Minister Gordon Brown came to see me and what was he talking about? Gays.

“Mrs Clinton [the US secretary of state] rang me. What was she talking about? Gays.”

Geometry and the height of the mountains on the moon

Galileo's image of the moon
Galileo's map of the moon.

Galileo Galilei matched careful observation of sunlight and shadows on the moon, with some beautiful geometry to estimate the height of lunar mountains, in 1609. He needed the Pythagoras’ Theorem and the quadratic formula, both of which middle school students should be familiar. Larry Phillips has a nice post describing how Galileo did the math. The image below (from Pioneers of Science shows how to get started.

From the Gutenberg Project eBook of Pioneers of Science by Oliver Lodge.

The Moon transits the Earth

(from NASA).

Perhaps one of the most amazing sequences of images ever taken. NASA’s Deep Impact spacecraft took these movies looking back at the Earth from 50 million km away. You can see the moon clearly crossing the face of the planet. This really resets your perspective. The full movie is below.