Galileo, by looking through a telescope, doing some drawings and thinking about what he saw, helped to undermine centuries of autocratic idiocy and woolly thinking. In doing so, he got himself locked up – but he also bridged the gap between Copernicus and Kepler, and paved the way for Isaac Newton and ultimately Albert Einstein to construct a complete description of the universe and our place within it.
—  Brian Cox, Human Universe

Global Image of Io by NASA on The Commons

(July 3, 1999) NASA’s Galileo spacecraft acquired its highest resolution images of Jupiter’s moon Io on July 3, 1999 during its closest pass to Io since orbit insertion in late 1995. This color mosaic uses the near-infrared, green and violet filters (slightly more than the visible range) of the spacecraft’s camera and approximates what the human eye would see. Most of Io’s surface has pastel colors, punctuated by black, brown, green, orange, and red units near the active volcanic centers. A false color version of the mosaic has been created to enhance the contrast of the color variations. The improved resolution reveals small-scale color units which had not been recognized previously and which suggest that the lavas and sulfurous deposits are composed of complex mixtures. Some of the bright (whitish), high-latitude (near the top and bottom) deposits have an ethereal quality like a transparent covering of frost. Bright red areas were seen previously only as diffuse deposits. However, they are now seen to exist as both diffuse deposits and sharp linear features like fissures. Some volcanic centers have bright and colorful flows, perhaps due to flows of sulfur rather than silicate lava. In this region bright, white material can also be seen to emanate from linear rifts and cliffs. Comparison of this image to previous Galileo images reveals many changes due to the ongoing volcanic activity. North is towards the top of the picture and the sun illuminates the surface from almost directly behind the spacecraft. This illumination geometry is good for imaging color variations, but poor for imaging topographic shading. However, some topographic shading can be seen here due to the combination of relatively high resolution (1.3 kilometers or 0.8 miles per picture element) and the rugged topography over parts of Io. The image is centered at 0.3 degrees north latitude and 137.5 degrees west longitude. The resolution is 1.3 kilometers (0.8 miles) per picture element. The images were taken on July 3, 1999 at a range of about 130,000 kilometers (81,000 miles) by the Solid State Imaging (SSI) system on NASA’s Galileo spacecraft during its twenty-first orbit. The Jet Propulsion Laboratory, Pasadena, California manages the Galileo mission for NASA’s Office of Space Science, Washington, DC. Image # : PIA02308


And that’s the broader theme


Today we’re treated to video proof of something the great Galileo predicted all the way back in the 16th century:

Galileo proposed that a falling body would fall with a uniform acceleration, as long as the resistance of the medium through which it was falling remained negligible, or in the limiting case of its falling through a vacuum.

Physicist Brian Cox visited NASA’s Space Power Facility in Cleveland, Ohio, where they house their Space Simulation Chamber, the world’s largest vacuum chamber, to demonstrate that any two objects dropped in a vacuum will fall at the same rate. Cox and a team of engineers used the vacuum chamger to drop a bowling ball and a bunch of feathers from the same height at the same time. Even though we all know what’s supposed to happen, actually watching happen with your own eyes is truly incredible.

The best thing about this video is the reaction it elicits from Cox and the engineers. Everyone knows how the experiment will end. Like us, they’ve been told what to expect. Like us, many of them have seen it demonstrated on a smaller scale. But something about watching a bowling ball and feathers fall from a great height, together, side by side, makes them gawk, giggle, and grin like children. I think that’s kind of wonderful.

We’ve said it before and we’ll say it again, science is super awesome.

[via io9]

Ted Cruz Compares Himself to Galileo, Calls Those Who Believe In Climate Change ‘Flat-Earthers’

A few days after accusing “global warming alarmists” like California Governor Jerry Brown (D) of ridiculing and insulting “anyone who actually looks at the real data” around climate change, newly-declared presidential candidate Ted Cruz (R-TX) upped his rhetoric against those who care about the issue.

Galileo’s objective lens

Author:Vittorio Crosten (frame)

Date:lens: late 1609 - early 1610 / frame: 1677

Materials:lens: glass, gilt brass / frame: ivory, ebony

Dimensions:lens diameter 38 mm / frame 410x300 mm

Objective lens used by Galileo for many observations in 1609-1610. In 1677, the Medici commissioned Vittorio Crosten to build the ebony frame in which the lens has since been preserved.

Museo Galileo

Message From the Moon

At first glance, these probably come across as little more than hastily painted watercolor sketches of the moon. That’s precisely what they are, actually. Attractive, yes, but certainly not high art.  

But hiding in their shadows lies a greater significance. The squiggled edges of that bleeding ink bear an observation that altered the heavens themselves. Or at the very least, our view of them.

The hand that traced these orbs belonged to none other than Galileo Galilei. They were included in his 1610 work Sidereus Nuncius (“The Sidereal Message”, which would make a great band name), the first scientific text based on telescope observations. To understand the significance of his illustrations, it helps to understand the world in which he drew them.

In 1610, cosmology, not that it had much to show for itself as a science, was still based on the ideas of Aristotle, who by this time had been dead for 18 centuries. So current! Copernicus’ observation that the Earth orbited the sun, first published in 1543, had begun to challenge Aristotelian supremacy, it wasn’t exactly a popular idea. 

Aristotle’s cosmological beliefs were based on the idea that the heavens were made of a perfect substance called “aether”, and therefore the circular motions and spherical shapes of heavenly bodies were also perfect. Earth, he claimed, was inherently imperfect, as were all the things that existed upon it. Everything in the heavens was awesome, and Earthly matter was inherently “just okay”, even if its name was Aristotle. This was one of the reasons people found Copernicus’ claims so hard to swallow. The imperfect Earth among the perfect heavens? Heresy!

Enter Galileo and his humble 20x telescope, in 1609. At the time, in Aristotelian fashion, the moon, being of the heavens, was assumed to be a perfect sphere, its dark and light areas just splotches upon the billiard-ball-smooth lunar surface. I imagine it took Galileo about 7 seconds of lunar observation to realize that was not the case.

The terminator, that line that separates the moon’s illuminated face from its dark one, is jagged as a crocodile’s smile. I’ve seen it myself through modern telescopes, and I must say, it’s really something to witness how light and shadow break over a distant crater’s edge. Galileo painted this in his sketches above, inferring that the moon in fact had a rough and crater-marked face. This meant that not only was Earth not the center of the universe, as Copernicus had shown, but the heavens themselves were imperfect, just like Earth.

Scientists would go on to realize that the orbits of heavenly bodies were not perfect circles, nor were the bodies perfect spheres, and that everything up there is made of the same stuff as everything down here. It was either a huge demotion for the heavens, or a great promotion for Earth, I’m not sure.

Galileo’s Sidereus Nuncius also included newly detailed maps of the constellations and the mention of four moons of Jupiter (although detailed observations of those were still centuries away), but it was his drawings of our moon that bore the most impact on future astronomical science, realigning the heavens with a single stroke of the brush.

Keep on drawing, and keep on looking up.

(You can read an English translation of Sidereus Nuncius here. If you’re hungry for more selenology, tour through these historical maps of the moon. Tip of the telescope to Steve Silberman for tweeting these sketches.)


A few weeks ago we featured Galileo a Madama Cristina de Lorena, published in 1896 by the Salmin Brothers, which happens to be the smallest book in the world printed with hand-set movable type.  The typeface used is called “flies’ eyes”, and was cut by Antonio Farina in 1834. We have another book in our collection printed with the same type, an 1878 edition of  La Divina Commedia di DanteWhile the Dante is also a miniature book, it is not nearly as small as the Galileo.  Here are some images of both books side by side, so you can compare the type and truly see just what a feat it must have been to hand-set both of these incredible little books.