Christmas Day

The day ended with four visits to the girls’ bedroom to rearrange various teddy bears who seemed to be wiggling out from under their (and Genevieve’s) blankets and two more visits to try to find a My Pretty Pony hair clip that had apparently fallen out of the toy’s plasticky locks and into Julia’s bed, but honestly the rest of the day was just great. The girls were thrilled by their “Santa gifts” this morning, and spent much of the day playing with one or several or all of their toys. Vivi and I did go outside to take advantage of the heavy, wet snow – nature’s Play-Doh! – and make a nice snowman (beside which Vivi and our next-door friend posed):
Christmas Day Snowman

Later, after we invited over for dinner some friends who were unable to travel in the bad weather, I did a bit of “skiing” in that snow, which was great for sucking my skis off the track. It was so warm out that I finished my ski without a hat or gloves on, which is a late-March or April stunt, not a Christmas Day one.

Dinner with those friends went very well: the food was delicious, the girls (our two and their two) played well together and enjoyed each other, and then before you knew it, bedtime was upon us. Only 364 more shopping days till Christmas!

Nightskiing Deserves a Quiet Night

Perfect. The only things I could hear while skiing tonight were my breath, my skis gliding, and my poles clicking.* It was a gorgeous night on the snow.**

Arb Ski Trails

* Admittedly, I’m half deaf, I left my hearing aids at home, and I wore a too-thick toque.
** This photo hardly does justice to how bright it actually is: the snow picks up my headlamp’s beam, the stars, ambient light from streetlights and campus buildings… The trails glow.

Galileo Looks at the Moon

Tonight, the moon is waxing toward a full moon on New Year’s Eve, which makes this as fitting a moment as any to note that almost exactly four hundred years ago, between November 30 and December 18, 1609, the Italian scientist Galileo Galilei used a hand-made telescope (and other tools, as shown in this excellent Smithsonian article) to look at the moon, examining it for the first time in human history like a scientist – indeed, using his looking to help invent modern science. Using the telescope, Galileo scrutinized the discolored areas that are visible with the naked eye. As put on an excellent webpage by an undergrad at Rice,

Galileo’s observations led him to the startling conclusion that the moon is anything but perfect. With his telescope, he noticed small dark spots that had never been seen before on the illuminated part of the moon’s surface, along with similar light spots in the dark area. He observed that as time passed, these and other spots changed, either getting lighter and eventually disappearing or getting darker and more distinct. The interface between the light and dark sides of the moon was rough and uneven, rather than smooth as would be expected on a perfectly smooth sphere. Galileo also observed that the spots all “have a dark part on the side toward the Sun while on the side opposite the Sun they are crowned with brighter borders like shining ridges.” (Sidereus Nuncius, p 41)

From these and many other observations, Galileo concluded that the moon’s surface consists of valleys, plains and mountains much like the surface of the Earth (Sidereus Nuncius, p 48-49). The dark spots are shadows cast by these mountains and valleys as the sun falls on them. As the moon’s position relative to the sun changes, the shapes and intensities of these shadows change. Galileo’s conclusion was a shocking one– how can the moon, a heavenly body, not be perfect and spherical? If the moon is imperfect, could there be other imperfect heavenly bodies as well? If heavenly bodies can be imperfect, why can the Earth not be a heavenly body? Galileo’s conclusions about the moon did not give solid proof of Copernicus’ theory, but his observations paved the way for the theory’s eventual acceptance.

Not only did Galileo help advance the earthshattering ideas that Earth is not the center of the universe, and that perhaps God had not made all of the universe in a perfect form, but he drew some awfully good pictures of the moon as he saw it through his telescope. Indeed, the art historian Samuel Edgerton argues, in his recent book, The Mirror, the Window, and the Telescope: How Renaissance Linear Perspective Changed Our Vision of the Universe (thoroughly reviewed here), that Galileo’s skill as a draftsman, and especially his knowledge of perspective (an artistic and scientific innovation which was not even a century old when Galileo learned it), enabled him to understand that the discolorations visible on the moon were actually the evidence of not just of imperfections like spots on cowhide, but of irregularities such as mountains and craters. In other words, drawing led directly to scientific discovery – and spun off great art such as these sketches by Galileo.

Six Phases of the Moon, by Galileo
Six Phases of the Moon, by Galileo
Four More Phases of the Moon, by Galileo
Four More Phases of the Moon, by Galileo

Expectations Fulfilled

As I huffed and puffed around the Carleton Arb this morning, I thought about how funny skiing is as a sport, in that you have to wait months and months to be able to actually do it – to ski, and not just prepare to ski. This year, thanks to Tuesday’s blizzard, I was able to go from biking and running to skiing in basically one day, skipping the painful cold-but-snowless phase we’ve had in previous years.

Being able to get back on snow again makes me very happy, of course, but my happiness is amplified by finding (again) that skiing is just as much fun as I remembered and hoped. With only three sessions on snow so far, I’m having the usual bad technique & low strength problems that plague skiers early in every winter (unless they were more gung-ho than me about rollerskiing and/or weight training), but the cycling has helped my legs stay decently strong, and the motions of skiing still simply feel right. On top of that, Carleton has arranged with the Northfield high school ski team  to have some very committed Northfield parents groom the ski trails in the Arb, which means that we can ski on real tracks all winter – a fantastic boon to anyone who skis or wants to ski. I dunno if skiing is technically the most fun you can have outdoors, but it’s up there. I can’t wait to get out there again tomorrow night.

Snow(drift) Day!

Every significant snowfall builds a big drift against the patio door, but this morning brought the biggest one we’ve ever had: about 6 inches taller than our convenient and smiley measuring stick.
Snow Day 2009: Patio Drift

I had to loop around the house to get to the drift, which extended back away from the house quite a ways.Snow Day 2009: Patio Drift from Outside

Thankfully, it was almost all light, fluffy snow, and I only needed ten minutes to remove it entirely, creating some good space for the girls to play later.
Snow Day 2009: Patio Drift Cleaned Up

If only I could have moved all the snow to our sledding “hill,” which is, annoyingly, still bare! Clearly, we need more snow.
Snow Day 2009: Almost-Bare Hill