Ever wonder where Groundhog day comes from? Notice that it’s about 1/2 way to Spring?
We are now halfway between the Winter Solstice (December 21) and the Vernal or Spring Equinox (March 20). It’s called a cross-quarter day is known as Imbolc (or some variation of that spelling) in the Celtic world It’s also a modern Neopagan celebration and part of the Wheel of the Year.
Imbolc is most commonly celebrated on February 2 (same as Groundhog Day and Candlemas on the Christian calendar) but it actually occurs, according to the position of the Sun on the ecliptic, at 11:20 pm EST on Thursday, February 3 this year.
This cross-quarter day has been known since antiquity – a 5,000 year-old Neolithic passage tomb at the Hill of Tara in County Meath, Ireland has an alignment with sunrise on Imbolc. The word Imbolc comes from the Celtic i mbolg or “in the belly” referring to pregnant ewes who soon give birth to spring lambs. It was viewed as the start of spring (even though snow may yet be on the ground), a time for weather prognostication, and to watch for animals emerging from their winter dens (sound familiar? Groundhog Day has its roots in similar Germanic pagan beliefs).
We used to think Pluto was all on it’s lonesome out in it’s far away orbit. It turns out, we just got lucky in finding it, and it’s part of a class of objects, now called Trans Neptunian objects. As more and more objects got discovered in the Kuiper belt it became pretty clear that there were good odds we’d find something larger than Pluto. In 2005 we did, it’s now called Eris.
When I was in high school (circa 1990), an extraordinary number of bridges in Vermont were crumbling, all at the same time. This is because they were all built in 1928 – 1929, and 60 years was apparently the lifespan of those materials given the upkeep and conditions. The reason all the bridges were built in such a short window of time was the great flood of 1927, which washed away over 1200 bridges in the state.
The Vermont Historical Society has this incredible video on the event, which is really something to behold (embedded below).
Ars Technica has a great article on the history of the telescope. But there was something entirely non astronomy related that struck me:
In 1608, Hans Lipperhey in the Netherlands applied for a patent on a pair of lenses, one with a much shorter focal length than the other, arranged in a tube. He called it a “spyglass” as it allowed the observation of greatly distant events from a secluded retreat—Lipperhey noted that counting coins from afar was a suitable use. The patent was denied because the device was so very easily constructed.
The big breakthrough came when Galileo was informed of Lipperhey’s failure to secure a patent. He was certainly aware of the Venetian prowess in lens grinding, as well as work in optics that Kepler had done. Galileo decided to make such a device for himself, inspired by a mixture of Renaissance gung-ho and a desire to make his name. Presumably, he reasoned that a device able to magnify distant objects would also minimize the uncertainty in their position, providing an improved version of the wall quadrant.
That’s a frightening thought, and one I hadn’t known before. Had that patent been granted, we may never have had the revolution in science in 1609, because Galileo wouldn’t have jumped into the telescope manufacturing business. That work is what sealed the fate of the geocentric solar system, and became a great leap forward for all physical sciences.
It turns out that we found, then lost, the cure for scurvy well before we eventually identified it as Vitamin C. There is an incredible write up of that story.
Now, I had been taught in school that scurvy had been conquered in 1747, when the Scottish physician James Lind
proved in one of the first controlled medical experiments that citrus
fruits were an effective cure for the disease. From that point on, we
were told, the Royal Navy had required a daily dose of lime juice to be
mixed in with sailors’ grog, and scurvy ceased to be a problem on long
But here was a Royal Navy surgeon in 1911 apparently ignorant of
what caused the disease, or how to cure it. Somehow a highly-trained
group of scientists at the start of the 20th century knew less about
scurvy than the average sea captain in Napoleonic times. Scott left a
base abundantly stocked with fresh meat, fruits, apples, and lime
juice, and headed out on the ice for five months with no protection
against scurvy, all the while confident he was not at risk. What
It’s really fascinating, definitely worth your time.
Sometimes, even as a person pisses you off, they make a point that you can’t ignore. In a recent forum discussion that I was involved in, scientists were accused of making pronouncements from on high. The argument was that scientists jump to a conclusion that seems desirable to them, and then treat it as an infallible truth.
Of course, my initial reaction was to pronounce that I, as a practicing scientist, never make pronouncements. But, looking at my articles from the perspective of someone who really knows absolutely nothing about science—as a practice or as a body of knowledge—I can see how one could see little beyond a list of assertions. The truth is more complicated, of course, but it’s a truth that science writers find challenging to convey. Science is impossibly broad, and the leading edge sits, precariously balanced, on a huge, solid, and above all, old body of knowledge. To illustrate this problem, I am going to tell you the story about how the speed of light came to be the ultimate speed limit for the entire universe.