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 SidereusNuncius 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.
Donate to join us in making sure it’s always “a day at the beach” for shorebirds!
Hi y’all! As you know…I’m a bona-fide bird nerd, particularly with conservation of coastal species, like shorebirds & seabirds. So two things very near & dear to me are, of course — birds & beaches!
South Africa’s gorgeous coasts support a large number of our beloved birds. They also are the fastest developing regions in the country (& the world!). We are seeing shorebirds disappear around the globe, and alarmingly fast (I’m talkin’ decreases like 40-60% of one of my favorites, White-fronted Plovers, in the W. Cape!), mostly due to habitat destruction and other human-caused issues. Since wildlife like shorebirds can tell us so much about the status of our coasts, finding effective conservation and awareness solutions is becoming incredibly urgent.
I’ve been offered a fantastic project for my Master’s (at Univ. of Cape Town, partnering with The Nature’s Valley Trust — a great South African environmental non-profit) to study endemic shorebirds in high-tourism coastal areas, using the research to balance human activity, reduce impacts of major threats, and keep our beaches healthy.
We’re backed by BirdLife South Africa, Cape Nature, Knysna Toyota, and local conservation & bird clubs as necessary research for the region(and the birds! and communities!).Now I need YOUR help to seal the deal.
Make sure to tag #ShareTheShores when sharing, so we can thank you for being awesome!
Follow & Like for updates, plus you’ll find a ton of rad information there, too!
This is where my (unpaid) blood, sweat, and tears have been focused this entire year (and there’s been a lot of all of that, phew)! I have been painstakingly working to gain the support make this happen — developing the project, networking with appropriate researchers, officials, and groups, applying for countless grants, awards, and sponsorships. I have put everything I possibly can into this, that is how important and necessary I absolutely know this is. PLEASE SIGNAL BOOST THE HECK OUT OF THIS!
This is the shape model of comet 67P/Churyumov-Gerasimenko. From the images taken on 14 July, the OSIRIS team has begun modelling the comet’s three-dimensional shape. The animated gif presented here covers one full rotation of the nucleus around its spin axis, to emphasise the lobate structure of the comet. This model will be refined as more data becomes available – it is still a preliminary shape model and some features may be artefacts.
by the way did I ever tell y’all about the time I got a blank message from nobody, sent on new year’s eve in 1969, when the internet didn’t exist?
because that happened
OKAY KIDS, LET’S LEARN ABOUT THE UNIX EPOCH
So back in the early days of computers, when we were trying to build clocks to keep all our computers in sync, we tried a bunch of different ways to synchronize them in ways that both normal people could use and programmers could utilize.
We just tried saying “The current time is THIS date” and just storing that date as some text, but while that was easy for humans, it was a bunch of different numbers that worked together in funny ways and computers don’t play nice with a bunch of random, arbitrary rules.
Not much worked, until we realized that we needed a BASELINE to compare against, and a way to represent the current time that covers everybody. So we came up with Unix time, because Unix was the style at the time. Essentially, Unix time represents any given time by saying “How many seconds ago was 12:00 AM on January 1, 1970 in Iceland somewhere?”. Recent enough to keep the numbers relatively small, far enough that nothing computer-y would fall before it, and consistent enough that there’d be no discrepancy based on where you are.
So what happens when you see the date “December 31, 1969” on a buggy message like this is that the computer received a bunch of zeroes by mistake and went “Oh, this must be a message!” Then when it tried to interpret it, it got to the date, found a zero, and said “Zero seconds since the Unix Epoch? I’ll round down - this was sent at the last second of New Year’s Eve, 1969! They’ll be so happy to finally get their blank message.”
And then the computer traipsed off on its merry way, because computers are fucking ridiculous.
Rockets often utilize liquid propellants for their combustion. To maximize the efficiency during burning, the liquid fuel and oxidizer must mix quickly and break up into an easily vaporized spray. One method to achieve this is to inject the fuel and oxidizer as liquid jets that collide with one another. For high enough flow rates, this creates a highly unstable liquid sheet that quickly atomizes into a spray of droplets. The animation above shows an example of two impinging jets, but rockets using this method would typically have more than just two injection points. Other rockets use co-axial or centrifugal injectors to mix and atomize the fuel and oxidizer prior to combustion. (Image credit: C. Inoue; full-scale GIF)