2013's first solar eclipse is a weird one: This afternoon, a stunning annular eclipse will blaze, ring-like, in Australian and Pacific skies. Here's how you can watch (even if you're not from down under).
Today, just before 21:30 UTC, the Moon will pass between Earth and the Sun, giving rise to what's called an annular eclipse. Also known as a "ring of fire" eclipse , today's annular effect will only be directly visible to sky-gazers in Australia, Papau New Guinea and boats floating in just the right patch of the Pacific Ocean – but that doesn't mean you can't watch! Here's what you need to know to catch a glimpse of this stunning solar event.
Top photo by Abel Pardo López.
What Is an "Annular" Eclipse?
Because the Moon's orbit is elliptical, there are times throughout the month when it is closer to our planet than others. On April 27th, the Moon was at "perigee," meaning it was closer to us then than any other point in the month. In contrast, today's Moon will be close to apogee, the point in its orbit at which it is furthest from our planet.
The Moon's distance from us means that its apparent diameter in the sky will be smaller than almost any other time this month, so when it passes between the Sun and the Earth, it won't be able to cover the Sun entirely. As a result, some parts of the globe will be able to witness not just any eclipse, but a complete ring of sunlight like the one pictured up top – the defining characteristic of an annular eclipse.
When & Where
Unfortunately for the Northern Hemisphere, the annular effect of today's eclipse will be visible from below the equator only. In fact, most of it will only be visible from the Pacific Ocean. Mainland observers in northern Australia and southeastern Papau New Guinea will be able to see the effect with their own eyes, and can find out exactly what time to watch with NASA's handy Annular Eclipse applet. The map above, one in a fantastic series created by Eclipse Maps' Michael Zeiler, illustrates when and where you can expect to catch the eclipse at its most spectacular-looking from various points along its path. There's a band running across Zeiler's map labeled "Path of the annular solar eclipse." These are the regions of the Earth from which the Sun's "ring of fire" will actually be visible. (To observers in Singapore, Malaysia, Indonesia, much of Australia, New Zealand and even Hawaii, today's will look much like any other partial solar eclipse). For everyone else: the eclipse begins at 21:25 UTC (that's 17:25 ET / 14:25 PT, May 9th) and can be enjoyed online.
Watch the Ring of Fire Online
Of course, most people don't live along this narrow band of the United States (or anywhere else along the path of the annular eclipse, for that matter). But that's okay; you can always watch it online.
Your best bet is probably to check out the SLOOH Space Camera, which will be streaming feeds from telescopes along the annular path beginning today at 17:25 p.m. ET/14:25 PT. SLOOH even has it set up so you can take pictures of the eclipse as it unfolds.
One of the benefits to watching the eclipse online, rather than in-person, is not having to worry about taking precautions when actually viewing the eclipse. Looking directly at the Sun — even during an eclipse, and, yes, even with sunglasses — is an awful, awful idea, and can permanently damage your vision. In the event you're reading this from Australia/Papua New Guinea, here's how to keep from searing your eyes out.
To safely view the eclipse, you'll want to go buy a solar filter. These come in a variety of forms from wearable solar shades, to attachments that you can affix to telescopes and binoculars. They'll cut the brightness by enough that you'll be able to catch glimpses of the Sun without frying your retinas.
If it's last minute or buying a solar filter isn't an option, Sky and Telescope has detailed instructions for viewing the eclipse with a variety of pinhole projection techniques. (The photograph featured here shows how skygazers in Madrid used projection techniques to view an annular eclipse back in 2005.) Here's the simplest one:
Poke a small hole in an index card with a pencil point, face it toward the Sun, and hold a second card three or four feet behind it in its shadow. The hole will project a small image of the Sun's disk onto the lower card. This image will go through all the phases of the eclipse, just as the real Sun does. Experiment with different size holes. A large hole makes the image bright but fuzzy; a small hole makes it dim but sharp. the ever-popular pinhole projector technique.
More advanced projection methods involve the use of a cardboard box, or the room of a house with a sun-facing window. You can click through for more details.