Posts Tagged ‘stars’
“The moon is a friend for the lonesome to talk to”*…
… and, as Bartosz Ciechanowski explains in a stunningly-illustrated essay, so much more. The moon affects our tides, our light, and even the Earth’s rotation– it’s no wonder that our constant companion has so haunted human culture…
… The Moon may be just an unassuming neighbor in the sky, but its presence affects our lives in many subtle ways. When it reflects sunlight off its scarred surface to guide the way in the darkness of night, or as it breathes life into oceans by rhythmically raising tides, or when it cloaks the Sun in a rare and awe-inspiring total solar eclipse, the Moon reminds us of the celestial world right outside of the safe confines of our planet.
Traveling through the cold and empty space by Earth’s side, the Moon is always just there. It may be barren and dull, but, undeterred by its own lifelessness, it never leaves us completely alone.
Perhaps the next time you catch a glimpse of the Moon’s shiny surface beaming in the night sky, you’ll see it a little differently – not as a mundane fixture of the heavens, but as a fellow companion that gently affects our own existence…
Absolutely fascinating– and beautiful: “Moon,” from @bciechanowski.bsky.social. Via @TheBrowser.
This is (R)D‘s second visit with Ciechanowski, who earlier helped us understand “Sound”; for more of his extraordinary work, visit his archive.
More on the moon and here.
* Carl Sandburg
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As we raise our eyes, we might send celestial birthday greetings to William Wilson Morgan; he was born on this date in 1906. As astronomer and astrophysicist, he was professor and astronomy director for the University of Chicago’s Yerkes Observatory in Wisconsin and managing editor of Astrophysical Journal. He was a leader in stellar and galaxy classification and helped prove the existence of spiral arms in our galaxy.
“It is clear that there is no classification of the Universe that is not arbitrary and full of conjectures. The reason for this is very simple: we do not know what kind of thing the universe is.”*…
… Still, scientists try. Ethan Siegel on the current state of play– with special attention to whether or not our cosmic landscape is endless or not, and why the Universe is so uniform on large scales, but so non-uniform on smaller scales…
13.8 billion years ago, our Universe as we know it began with the hot Big Bang, which gave rise to a primordial soup of particles and antiparticles that led to the planets, stars, and galaxies we know today. The hot Big Bang itself was set up by a preceding phase known as cosmic inflation, but only the final tiny fraction-of-a-second gets imprinted onto our observable Universe. What we can observe about the Universe is finite, but what about the unobservable parts that lie beyond it: are they finite or infinite? What the data can tell us is limited, but here’s what we think and why…
Read on to find out: “Is the Universe finite or infinite?” from @StartsWithABang in @bigthink.
* Jorge Luis Borges, in “The Analytical Language of John Wilkins”
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As we stargaze, we might send sunny birthday greetings to Herbert Friedman; he was born on this date in 1916. A physicist and astronomer, he made seminal contributions to the study of solar radiation. Friedman joined the Naval Research Laboratory in 1940 and developed defense-related radiation detection devices during WW II. In 1949, he obtained the first scientific proof that X rays emanate from the sun, when he directed the firing into space of a V-2 rocket carrying a detecting instrument. Through subsequent rocket astronomy, he also produced the first ultraviolet map of celestial bodies, and gathered information for the theory that stars are being continuously formed, on space radiation affecting Earth, and on the nature of gases in space. Friedman also made fundamental advances in the application of x rays to material analysis.
“Aurora had but newly chased the night, / And purpled o’er the sky with blushing light”*…
The solar storms of late have made for some compelling nighttime sky-gazing. But these geomagnetic storms can have serious consequences, for example power grid irregularities, degradation of high-frequency communications, GPS outages, and satellite navigation issues. To that lattermost, consider agriculture: a 2023 report by the US Department of Agriculture noted that more than 50 percent of corn, cotton, rice, sorghum, soybeans, and winter wheat are planted and harvested with “automated guidance.” These systems, on which farmers depend, especially in the mid-May planting season, have been compromised…
The powerful geomagnetic storm that cast the northern lights’ vivid colors across the Northern Hemisphere over the weekend also caused some navigational systems in tractors and other farming equipment to break down at the height of planting season, suppliers and farmers said…
Farm equipment suppliers had warned that the storm would result in disruptions. And on Saturday, Landmark Implement, which sells John Deere farming equipment across parts of the Midwest, said that the accuracy of some of its systems had been “extremely compromised” because of the event [as has the equipment of other manufacturers].
The company said in a statement that it was searching for a “tool to help predict this in the future so that we can attempt to give our customers an alert that this issue may be coming.” It described the storm as a “historic event” rather than something it would have to “continue to battle frequently.”
Terry Griffin, an associate professor in agricultural economics at Kansas State University, said that while infrequent, such storms still posed a threat to farming in the United States, where the majority of crops are planted using modern guidance systems.
“This was the first time we’ve had geomagnetic storms that were so strong, and we were reliant upon GPS,” he said, noting that among the worst times for a storm like this to occur was during the planting season, when precision is crucial. Alternative technologies, including systems that use machine vision and artificial intelligence, or a more localized navigation system that would not collapse in a solar storm, are being developed, Dr. Griffin added…
The Northern lights are beautiful, but their cause is playing havoc with agriculture: “Solar Storm Crashes GPS Systems Used by Some Farmers, Stalling Planting” (gift article) from @nytimes.
See also: “Solar Storm Knocks Out Farmers’ Tractor GPS Systems During Peak Planting Season.”
* John Dryden
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As we ruminate on radiation, we might spare a thought for Williamina Fleming; she died on this date in 1911. An astronomer and scholar of stars like our Sun, she was hired by the director of the Harvard College Observatory to help in the photographic classification of stellar spectra. She helped develop a common designation system for stars and cataloged more than ten thousand stars, 59 gaseous nebulae, over 310 variable stars, and 10 novae and other astronomical phenomena. Among several career achievements that advanced astronomy, Fleming is noted for her discovery of the Horsehead Nebula in 1888.
“I’m sure the universe is full of intelligent life. It’s just been too intelligent to come here.”*…
Email migration should now be complete; email subscribers should now be getting (Roughly) Daily via Mailchimp, and should not be getting a duplicate from Feedburner. If you are getting a dupe, please let me know (roughlydaily@gmail.com). Note that this new service may be landing in your Gmail “Promotions” folder; you can move it to your main folder. With apologies for the turbulence over the last few days, and thanks for your continued reading, on to today’s post…
A new computer simulation shows that a technologically advanced civilization, even when using slow ships, can still colonize an entire galaxy in a modest amount of time. The finding presents a possible model for interstellar migration and a sharpened sense of where we might find alien intelligence.
Space, we are told time and time again, is huge, and that’s why we have yet to see signs of extraterrestrial intelligence. For sure, the distances between stars are vast, but it’s important to remember that the universe is also very, very old. In fact, I’d go so far as to say that, in terms of extremes, the Milky Way galaxy is more ancient than it is huge, if that makes sense. It’s for this reason that I tend to dismiss distances as a significant variable when discussing the Fermi Paradox—the observation that we have yet to see any evidence for the existence of alien intelligence, even though we probably should have.
New research published in The American Astronomical Society is bolstering my conviction. The new paper, co-authored by Jason Wright, an astronomer and astrophysicist at Penn State, and Caleb Scharf, an astrobiologist at Columbia University, shows that even the most conservative estimates of civilizational expansion can still result in a galactic empire.
A simulation produced by the team shows the process at work, as a lone technological civilization, living in a hypothetical Milky Way-like galaxy, begins the process of galactic expansion… Things start off slow in the simulation, but the civilization’s rate of spread really picks up once the power of exponential growth kicks in. But that’s only part of the story; the expansion rate is heavily influenced by the increased density of stars near the galactic center and a patient policy, in which the settlers wait for the stars to come to them, a result of the galaxy spinning on its axis.
The whole process, in which the entire inner galaxy is settled, takes one billion years. That sounds like a long time, but it’s only somewhere between 7% and 9% the total age of the Milky Way galaxy.
…
As noted, the new model is constrained by some very conservative rules. Migration ships are launched once every 10,000 years, and no civilization can last longer than 100 million years. Ships can travel no farther than 10 light-years and at speeds no faster than 6.2 miles per second (10 kilometers per second), which is comparable to human probes like the Voyager and New Horizons spacecraft.
“This means we’re not talking about a rapidly or aggressively expanding species, and there’s no warp drive or anything,” said Wright. “There’s just ships that do things we could actually manage to do with something like technology we can design today… Even under these conditions, the entire inner part of the simulated galaxy became settled in a billion years. But as Wright reminded me, our “galaxy is over 10 billion years old, so it could have happened many times over, even with those parameters.”…
A new simulation published by the American Astronomical Society suggests that aliens wouldn’t need warp drives to take over an entire galaxy in (relatively) short order, as George Dvorsky (@dvorsky) explains.
[Image above: Andromeda Galaxy, source]
* Arthur C. Clarke
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As we spread out, we might spare a thought for Jacobus Cornelius Kapteyn; he died on this date in 1922. An astronomer, he used photography and statistical methods to determine the motions and spatial distribution of stars (especially with the Milky Way), the first major step after the works of William and John Herschel. He introduced absolute magnitude and color indexing as standard concepts in cataloguing stars.
Kapteyn was also among the first to suggest the existence of dark matter (which he deduced from examining stellar velocities).
“Loki’d!”*…
January 2, 1961: 100,000 spectators filled Pasadena’s Rose Bowl stadium to watch the Minnesota Golden Gophers take on the Washington Huskies in the New Year’s Day game (played that year on January 2 because the 1st fell on a Sunday). Millions more watched around the nation, crowded in front of tv sets in living rooms, restaurants, and bars.
NBC was providing live coverage of the game. At the end of the first half the Huskies led 17 to 0, and the audience settled in to watch the half-time show for which the Washington marching band had prepared an elaborate flip-card routine.
Sets of variously colored flip cards and an instruction sheet had been left on seats in the section of the stadium where the Washington students were located. When the students heard the signal from the cheerleaders, they were each supposed to hold up the appropriate flip card (as designated by the instruction sheet) over their head. In this way different gigantic images would be formed that would be visible to the rest of the stadium, as well as to those viewing at home. The Washington band planned on displaying a series of fifteen flip-card images in total.
The flip-card show got off to a well-coordinated start. Everything went smoothly, and the crowd marvelled at the colorful images forming, as if by magic, at the command of the cheerleaders. It wasn’t until the 12th image that things began to go a little wrong. This image was supposed to depict a husky, Washington’s mascot. But instead a creature appeared that had buck teeth and round ears. It looked almost like a beaver.
The next image was even worse. The word ‘HUSKIES’ was supposed to unfurl from left to right. But for some reason the word was reversed, so that it now read ‘SEIKSUH’.
These strange glitches rattled the Washington cheerleaders. They wondered if they might have made some careless mistakes when designing the complex stunt. But there was nothing for them to do about it now except continue on, and so they gave the signal for the next image.
What happened next has lived on in popular memory long after the rest of the 1961 Rose Bowl has been forgotten. It was one of those classic moments when a prank comes together instantly, perfectly, and dramatically.
The word ‘CALTECH’ appeared, held aloft by hundreds of Washington students. The name towered above the field in bold, black letters and was broadcast to millions of viewers nationwide.
For a few seconds the stadium was plunged into a baffled silence. Everyone knew what Caltech was. It was that little Pasadena technical college down the road from the Rose Bowl stadium. What no one could figure out was what its name was doing in the middle of Washington’s flip-card show. Throughout the United States, a million minds simultaneously struggled to comprehend this enigma.
In fact, only a handful of people watching the game understood the full significance of what had just happened, and these were the Caltech students who had labored for the past month to secretly alter Washington’s flip-card show…
More on one of the great pranks of all time: “The Great Rose Bowl Hoax,” via The Museum of Hoaxes.
See also this explication of one of the more successful imitators.
* Tom Hiddleston
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As we treasure tricksters, we might recall that on this date in 2006 the City Councils of Reykjavik and its neighboring municipalities agreed to turn off all the city lights in the capital area for half an hour, while a renowned astronomer talked about the stars and the constellations on national radio.
(Ten years later they dimmed again to allow unpolluted viewing of the Northern Lights.)
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