New Yorkers were wowed on Wednesday by a sunset that was perfectly framed by skyscrapers, thanks to an urban astronomical phenomenon known as Manhattanhenge.
The same planetary tilt that determines the seasons also dictates exactly where the sun will go down each evening — and because of the way that Manhattan's dominant street grid is laid out, killer sunsets are potentially visible from some of the borough's best-known east-west streets in late May and mid-July.
Tuesday's ceremony was rained out, but the skies were clear enough on Wednesday to make for some beautiful postings on photo-sharing sites such as Instagram and Twitter, Flickr and Facebook.
Doing a search for the hashtag #Manhattanhenge on Twitter will bring up a nice selection — including Edgar Gonzalez's view from 34th Street, which you see above.
Another picture from Gonzalez shows the scene just before Manhattanhenge reached its climax at 8:15 p.m. ET. For better or worse, sunset-watching crowds have become a big part of the phenomenon.
"Not sure which was cooler: Manhattanhenge itself or all the people standing in the middle of the street," Courtney Mauk tweeted. "Drivers did not seem amused."
"NYPD could make a fortune tonight giving jaywalking tickets," Scott Wittrock observed.
The traffic issue is of growing concern to Neil deGrasse Tyson, the director of New York's Hayden Planetarium. Tyson is the guy who threw the celestial spotlight on Manhattanhenge more than a decade ago, in a magazine article that was accompanied by his glittering sunset photo.
"Back then, it was just kind of a curiosity, but now it's becoming an annual tradition," Tyson told NBC News. "It started out with tens of people, and then hundreds, and now there are thousands of people who block traffic. I've alerted the police department of this, just as an issue of public safety, that perhaps they should close off streets. We're still trying to resolve that. They're not accustomed to closing off streets for cosmic reasons."
Why is Manhattanhenge such a big deal for New Yorkers? One reason may be that urban residents are starved for cosmic wonders. "They may not receive much of the universe, but when they can, they reach for it. And that's what's going on tonight, and of course for the next one in July," Tyson said Wednesday.
Check out Tyson's guide to Manhattanhenge for more background and a rundown of the times for July's Manhattanhenge events (8:23 p.m. ET on July 12 and 8:24 p.m. ET on July 13). He says the best streets for sun-watching are 14th, 23rd, 34th, 42nd, 57th and several streets adjacent to them. Did you snap some great Manhattanhenge pictures? Share them on the NBC News Science Facebook page, and stay tuned for more in July.
More celestial alignments:
- 2012: Manhattanhenge wows New Yorkers
- Astronomical alignment found at Peru pyramid
- Feast your eyes on a new Stonehenge theory
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.