An animated image shows the track of the moon's shadow during the July 11 total solar eclipse. Click through an interacttive that explains eclipses.
Eclipse chasers are known to go to the ends of the earth for just a few minutes of totality, and this weekend the ends of the earth just happen to be on exotic islands in the South Pacific. But if you can't make it to Easter Island in time, you can still chase Sunday's total solar eclipse ... over the Internet.
Seeing an eclipse on your computer screen can't possibly match catching sight of the black sun in person, of course. Not everyone can spare the time and money to go on eclipse expeditions, however, and experiencing the eclipse online can still give you a glimpse of one of nature's rarest phenomena. You'll also feel the thrill of the hunt - because eclipse-watching over the Web, like eclipse-watching in person, involves more than a little bit of persistence and luck.
First of all, it takes quite a bit of sleuthing to track down which websites offer streaming video of the sight. We've done some of that spadework for you, and I'm hoping that Cosmic Log correspondents will provide more pointers in the comment section. But that's just the beginning. If past eclipses provide any guide, there'll be lots of frantic clicking from site to site, looking for online destinations where the webcam skies are clear and the network connections aren't swamped.
When to start chasing
The first thing to keep in mind is the time: Totality will be visible only from a thin track that runs through the South Pacific. The event begins at sunrise on the west end of the track, and quickly runs eastward toward sunset on the other side of the track, as shown in Andrew Sinclair's animated graphic above.
The central part of the moon's shadow touches down around 2:15 p.m. ET Sunday, zooms over the ocean, hits the French Polynesian island of Tatakoto around 2:45 p.m. and passes over Easter Island's throngs starting at 4:08 p.m. ET. The eclipse finishes up over Chile and Argentina, near the southernmost tip of South America, at 4:51 p.m. ET.
The total phase of the eclipse lasts only a few minutes at most. The partial phase, during which the moon slowly covers up the sun's disk and then retreats, lasts much longer - about an hour and a half on each side of totality on Easter Island, for instance.
Where to look on the Web
If you're up for Web-based eclipse-chasing, check out these sites during the partial phase, and be prepared to switch around as the climax nears for each region:
- Live.Saros.org: Researchers from the Canary Islands are on Tatakoto and promise to send back live pictures. Follow their adventures on this Spanish-language blog.
- Live!Eclipse 2010: Japan's Live!Eclipse webcasts have been beamed from a string of solar eclipse sites, and this time around, streams may be available from multiple locations. Watch the team's UStream channel for coverage.
- SolarEclipse.eu: Several groups from Spain and the Canary Islands, including the Ciclope research team and the Shelios science information venture, are collaborating to send back video from Easter Island.
- Eclipse Tahiti: French-language website promises coverage of the eclipse via a UStream channel.
During last year's Asian eclipse, Indian television networks were the standouts for Web streaming. So it's worth checking in with the streaming TV coverage from these Chilean and Argentinian news networks, just in case they have reporters on Easter Island or the South American mainland:
- 24 Horas (Chile)
- TV de Chile on UStream (or via Eclipse2010.org)
- LND TV 24 Horas (Argentina)
- TN (Argentina)
If you totally miss totality, you can still catch up on the coverage by checking in with Dan Falk's Easter Island dispatches on New Scientist's Culture Lab, plus his Twitter updates. NASA Science News promises to provide post-eclipse images of totality, and the National Geographic Channel is scheduled to air an eclipse special at 11 p.m. ET Sunday. And of course you can rely on msnbc.com to have a full report.
Then what? The next big event is a total lunar eclipse on Dec. 21, with prime viewing from North America. NASA lists a series of partial solar eclipses next year, but the next dose of solar totality won't be available until Nov. 13, 2012. And if you're an American who's hankering to see totality from your own country, you'll have to wait until 2017. That'll give you plenty of time to work on your eclipse-chasing skills, online and maybe even in person.
More about eclipses:
- Interactive: What causes a solar eclipse?
- Slideshow: Greatest hits from eclipses
- Quiz: Test your knowledge of eclipse lore
- The truth behind eclipses (vampires not included)
- Shadow and Substance: Eclipse in motion
- How to view the sun safely
- NASA Eclipse Website
Update for 3:55 p.m. ET July 11: We're down to the final minutes before totality on Easter Island and I haven't been able to chase down the eclipse yet. But it looks as if SolarEclipse.eu (a.k.a. Shelios) is the best bet, with the Live!Eclipse Ustream webcast still a possibility. When it comes to South American TV coverage, TN in Argentina seems to be the best hope. The show is already over on the western part of the track, and SpaceWeather.com is already getting some great pictures.
Update for 3:57 p.m. ET July 11: Video coverage is available via SolarEclipse.eu. Yee-haw!
Update for 5:35 p.m. ET July 11: The eclipse is over - what a cool sight! Be sure to check in with SpaceWeather.com, tonight's National Geographic Channel special, New Scientist's Culture Lab and of course our own eclipse coverage on msnbc.com for follow-ups.
Update for 6:38 p.m. ET July 11: Don't miss Daniel Fischer's pictures from an Andean vantage point on Twitpic.
Update for 8:15 p.m. ET July 11: Here's another SpaceWeather stunner from Janne Pyykkö.