If you can't make it to the South Pacific's eclipse zone in time to watch the sun turn into a "ring of fire" on Thursday, you can still get in on the spectacle online.

The annular solar eclipse begins at 6:30 p.m. ET (22:30 GMT) in western Australia. Over the course of several hours, the moon's shadow will sweep across Australia, Papua New Guinea, the Solomon Islands and the Pacific from east to west, fading into the sunset off the coast of South America.

Because of the relative position of moon, sun and Earth, the moon can't cover the sun's disk completely. For observers who are situated within a strip of Earth's surface that measures 100 to 140 miles (171 to 225 kilometers) wide and thousands of miles long, only the outer edge of the sun will remain uncovered. That's what produces the eerie ring of fire.

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The sight will be much like what was visible during last May's annular solar eclipse, and the course of the eclipse will be similar to the Pacific path that was taken by the moon's shadow during last November's total solar eclipse.

If you are in the zone for the ring of fire, be careful: Even that slim ring of sunshine packs enough of a punch to burn your eyes, and you'll need to take precautions. Those precautions can take the form of eclipse-viewing glasses or filters, or pinhole-camera rigs that let you view the eclipse indirectly.

Caution should be the watchword as well for those who can observe the eclipse's partial phase from a wide swath of the Pacific, ranging from New Zealand to Indonesia and Hawaii, as shown in the animation below. NASA's Eclipse website provides further details, including precise time schedules for the eclipse in a variety of locales.

If you're entirely outside the eclipse zone, you won't be so sorely tempted to gaze at the sun. Instead, you can enjoy totally safe views of the eclipse online. Click on the links below for a few of the options:

Slooh Space Camera: Slooh's coverage begins at 5:30 p.m. ET, during the partial phase that leads up to annularity. Slooh's team will provide the commentary for live video feeds from Tennant Creek, Cape Melville National Park and Cairns in Australia. The show also will feature occasional shots of the unsullied sun from Arizona's Prescott Observatory. You can use a Web browser or Slooh's iPad app to tune in.

Coca-Cola Space Science Center: The Georgia-based center will provide a live video feed from Australia's Cape York starting at 5 p.m. ET.

Amateur webcams: Australian skywatcher Gerard Lazarus is gearing up to capture live video of the eclipse, and there may be other on-the-fly feeds. Follow the Twitter hashtag #ASE2013 for updates. 

Television Down Under: The eclipse is likely to make news Down Under, and it's worth checking Sky News Australia and 3News in New Zealand for TV coverage.

If you miss it: Check SpaceWeather.com, Space.com and Universe Today for images of the eclipse after it takes place. You'll also want to keep tabs on Geoff Sims (@beyond_beneath) and Colin Legg (@colinleggphoto) on Twitter.

If you catch it: Got pictures? Please feel free to share 'em with us via NBCNews.com's FirstPerson photo upload page, and we'll pass along a selection of eclipse pics.

More about the eclipse:

• All about the 'ring of fire' eclipse
• Australia to see second solar eclipse in six months
• Flash interactive: What causes a solar eclipse?

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Tip o' the Log to Michael Zeiler and Amanda Bauer for eclipse tips.

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.

It might sound scary to hear that a giant blob of solar plasma is heading straight for us, but don't panic: Space weather forecasters say this solar outburst should deliver nothing more than a spectacular show up north.

"We're not going to be in for a big disturbance," said Norm Cohen, senior forecaster at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Colorado. "The northern tier of the United States might be able to see aurorae."

The outburst of electrically charged plasma — also known as a coronal mass ejection, or CME — blasted out from the sun on Jan. 13, sparking a radio blackout. It's taken several days for the blob itself to travel the 93 million miles between the sun and here, but forecasters now expect it to sweep over Earth's magnetic field early to midday Thursday.

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When strong solar storms interact with the magnetosphere, they can spark satellite outages and disrupt electric power grids. Fortunately, this one shouldn't be that strong. (In geekspeak, let's just say that the maximum Kp is expected to reach no higher than 4. NOAA's space weather scale lays out the effects associated with higher Kp levels. Check out the prediction center's Facebook page for space weather updates.)

The most visible effect should be the northern lights generated by the interaction between the electrically charged solar particles and atoms in Earth's upper atmosphere, as explained on the "Causes of Color" website. This week's geomagnetic flare-up should add to what's already been a great week for auroral displays in northern latitudes.

Chad Blakley, a photographer at Sweden's Abisko National Park, sent in the beauty you see above. "It looks like there may be more powerful auroras in the days ahead," Blakley said in an email. "It is a very good time to be an aurora photographer!"

For more of Blakley's beauties, check out the Lights Over Lapland website or the LOL Facebook page.

Glowing reports are coming in from space as well. Here's a picture captured by the Department of Defense's DMSP F-18 OLS low-light imager on Jan. 13. The green outlines show Ireland and Britain down south, and Iceland and Scandinavia up north. The ghostly wisps crossing the frame are the northern lights. It's conceivable that the bright streaks you see in this satellite picture are the same ones visible in Blakley's pictures.

Are there more solar blasts heading our way? SpaceWeather.com notes that a complex sunspot region known as AR1654 is pointing in our direction and has the potential to send more big blobs of plasma our way. But Cohen said the worries about that particular sunspot have been receding.

"It's been fairly quiet in terms of flare production," he said. "If anything, it's beginning to show signs of decay."

In fact, there's been increasing talk that this year's expected peak of the sun's 11-year activity cycle could be relatively wimpy. Cohen said he didn't want to make that sweeping of a prediction — but he did admit that there hasn't been as much disruption as some people might have feared.

"The activity hasn't been all that impressive yet," he said.

More auroral glories:

• Top spots to see the northern lights
• Video: Northern lights captured on camera
• Cosmic Log archive on auroras

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Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other 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.

The dolphins didn't come out for today's total solar eclipse in the Coral Sea, but hundreds of tourists were on deck to catch our cruise ship's biggest show. And most importantly, the sun came out as well.

That was the whole point behind seeing the eclipse from the Dawn Princess, which has been making stops along Australia's northeast coast for the past week. It may not be the steadiest viewing platform, but an expert navigator can sail to a spot in the narrow track of totality where clouds won't spoil the view.

"This is the real advantage of being on a ship," Patricia Reiff, director of Rice University's Space Institute, told me during today's eclipse extravaganza.

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Solar eclipses occur when the moon passes in front of the sun, and the partial phase of today's event could be seen from a wide swath of the Pacific. But the total phase — during which the moon's disk blots out the entire solar disk — is visible only from a strip of Earth's surface measuring thousands of miles in length and less than 100 miles in width. The Dawn Princess' southeast course from Australia's Port Douglas to Sydney was plotted out to put the ship and its nearly 2,000 passengers right in the middle of that track at eclipse time, which was 6:39 a.m. local time on Wednesday (on the Western Pacific side of the International Date Line).

By 4:30 a.m., Reiff and her group from EclipseTours.com staked out a prime spot on the port side of the ship's top deck, near at the stern. This was Reiff's 13th solar eclipse, but it was the first brush with totality for Andrea Pond, one of the tourists in the group. She was sailing on the Dawn Princess along with her husband, Stan, who was an eclipse-chaser long before he married Andrea.

"It's not everyone who wakes up at 4 in the morning to see a two-minute happening," Andrea said.

I was on the cruise with my wife, two of my brothers, my sister and a few friends, but Reiff let me tag along with her group as well. So I was with the other eclipse-chasers at about 5:45 a.m., just after sunrise, when German astronomer Joachim Biefang peered through his solar telescope and cried out "First contact!"

First contact was when the moon's disk began passing over the sun's disk. We had to wear freaky-looking solar-filter glasses to watch the moon slowly chew away at the sun.

The ship's course was nearly perfect: Once the sun climbed above a bank of clouds on the horizon, we had a wide-sky view. "Let's have a little gratitude, everybody," Reiff told her group, which had swelled to a couple of dozen of people in one of the ship's sweetest viewing spots.

Hundreds more staked out their own positions around the top deck. My family was along the rail, near the halfway point on the port side. My brother Steve and his wife, Joan, recalled how a troop of dolphins popped up on the surface during their 1998 eclipse cruise in the Caribbean — and they hoped it would happen this time as well. They speculated that the marine mammals would want to find out the reason for the darkening sea.

We kept looking back behind the ship in case the sea erupted with dolphins, but the sun was the center of attention. As we counted down to totality, we folded our fingers together and held them up to project crescent-shaped images onto the deck. Soon the sun's light faded to an eerie golden shade. "It's like a storm is coming," my sister Donna said.

In the moment before totality, the sun's crescent was transformed into a glowing circlet with a bright flash — the famous "diamond-ring effect." That's when the crowd erupted in a cheer, which was followed by oohs and ahhs as the diamond ring turned into a ghostly coronal ring around the totally blacked-out sun. The sky took on a velvety shade of dark violet, with Venus and the southern stars glittering above us.

I oohed and ahhed along with everyone else, and snapped a couple of fuzzy photographs. But mostly, I just marveled at the eerie sight. I imagined how freaked out ancient observers must have been when the sun disappeared, and how relieved they must have been when it returned.

Before we knew it, another diamond ring flashed, the sea and sky brightened again, and my fellow travelers basked in the afterglow.

"It was perfect," one tourist gushed. "I can die now."

"Let's turn the ship around and do it again," Biefang joked.

"If I were a smoker, I'd have a cigarette," Reiff said with a smile of satisfaction.

"Want to look for dolphins?" my wife, Tonia, asked me.

When we went back to the ship's stern, we didn't find any dolphins. But we did find Brian Verkaart, who had just gotten engaged to his girlfriend, Sue Yee Duong.

"Five years, seven months and 12 days ago we met," Verkaart said. "I caught her checking out my butt."

Verkaart, who now has three solar eclipses under his belt, decided that the 14th of November was the perfect day to propose. He explained that he and Duong often exchange text messages that read "143," which is shorthand for "I love you." After the eclipse's second diamond ring, Verkaart turned to her and said something like, "Gee, this is the 14th. It'd be great if there were three diamond rings — and here's that third diamond ring."

That's when he got on his knees, offered her the engagement ring and proposed. Duong was totally surprised, but she said yes. ("At least he had the common sense not to pop the question during totality," my brother Steve said when he heard the story.)

Now my family and most of the other passengers on the Dawn Princess have gotten back into the cruise routine. Reiff and her fellow eclipse-chasers are swapping photos and planning their next cruise to totality. Verkaart is faced with the challenge of figuring out how to top his diamond-ring surprise.

And the dolphins?

If they had feet, they'd be kicking themselves right now. They missed a heck of a show.

More about the eclipse:

• PhotoBlog: Why I follow solar eclipses 
• Crowd cheers Pacific solar eclipse
• Next date with totality: 2015
• Video: Nightly News recaps the eclipse
• Flash interactive: How a solar eclipse happens

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My cruise on the Dawn Princess continues for a few more days, and then I'll be vacationing in New Zealand for another week. I might have a chance to write a postcard or two while I'm in Middle Earth, but regular postings to Cosmic Log won't resume until Nov. 27.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other 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.

More than 50,000 tourists are expected to converge on Australia for the year's only total solar eclipse on Nov. 13-14 — and I'm one of them. If you're not, don't despair: There'll be ample webcasts of the event, thanks to the magic of the Internet.

Most of the throngs will gather in Australia's northern province of Queensland, "Gateway to the Great Barrier Reef," which is already getting set for the additional crush of visitors.

"The challenge and the opportunity is that it takes place over such a short space of time ... but we're not focused on just the black spot in the sky; it's how we use the opportunity to promote the destination," Tourism Queensland's Jeff Gillies told The Cairns Post. The economic impact could amount to $75 million or more. And that's in Australian dollars.

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The psychological impact can be just as stunning, even though totality lasts only a few minutes at most: When the moon fully covers the sun's disk, the skies darken and the delicate glow of the sun's corona becomes visible around that black spot.

Linda Bugbee, a tourist from Virginia who is heading to Australia to see her fourth solar eclipse, told The Associated Press that her first brush with totality "was a lot more emotional than I expected."

"Time sort of stops, but you know it's only going to last a minute or so," she said. "You sort of take the universe and the planets for granted, but when this happens, it seems so real."

It all seems so unreal for me: While Linda Bugbee and her husband will be watching the eclipse from the city of Cairns on Nov. 14, I expect to be looking up from the deck of a cruise ship off Australia's east coast. The Dawn Princess is due to find a clear patch of sky somewhere within the track of totality, which measures roughly 100 miles wide from north to south, and thousands of miles long from east to west.

The eclipse begins at sunrise in Australia's Garig Ganak Barlu National Park, and ends at sunset about 500 miles west of Chile. A partial solar eclipse will be visible across a wider stretch of the Pacific, Australia, New Zealand, Antarctica and South America. This video shows you how the event will develop during the day.

Post-dawn darkness is due to fall on Cairns at 6:39 a.m. AEST on Nov. 14, which translates to 3:39 p.m. ET Nov. 13. You should be able to follow the eclipse online via these webcams:

• University of North Dakota's SEMS team on Ustream.
• Panasonic Eclipse Live plans solar-powered webcast.
• Gorge Creek Orchards in Mareeba in northern Australia.
• Total Solar Eclipse from Brisbane on the Australian coast.
• Total Solar Eclipse from Oak Beach near Cairns.
• Eclipse 2012 promises a webcast that will be carried by NASA.

There'll surely be more webcams available as we get closer to the event. Please feel free to add your favorites in the comment space below. I'll  fill you in on my own brush with totality after the eclipse — but for most of this month, I'll be vacationing Down Under and touring Middle Earth. Regular postings to Cosmic Log won't resume until Nov. 27. In the meantime, turn to NBCNews.com's Science and Space sections to keep on top of the news. G'day, mates!

More resources for eclipses:

• Eclipse-Maps.com
• Newcastle Astronomical Society
• Port Douglas Solar Eclipse 2012
• Destination Cairns by Daniel Fischer
• Wikipedia: Solar eclipse of November 13, 2012
• NASA: Total Solar Eclipse of 2012 November 13

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Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other 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.

Is this heaven? No, it's Greenland — lit up by a dazzling display of refracted sunlight.

These pictures are from Ed Stockard, who's part of the team at Summit Station on the peak of the Greenland ice cap. The research facility, which is funded by the National Science Foundation, serves as an observation post for the complex interactions between the atmosphere and one of the world's biggest reservoirs of ice.

The station is also an observation post for sky phenomena ranging from the northern lights to sun halos. And judging by his Flickr photo gallery, Stockard is getting an eyeful this season.

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But there's more than meets the eye: Over at the Atmospheric Optics website, Les Cowley points out 11 separate optical phenomena that are on display. The combination of halos, arcs, sun dogs and a sun pillar has earned Stockard's Arctic scene a place as the Optics Picture of the Day.

You don't have to live in the Arctic to see the sun's weird effects. In midnorthern latitudes, this time of year brings misty days, and even some days when ice crystals hang in the air. That's prime time for halos, sun bows and moon bows, fog bows and more. Cowley's website guides you through all the magic that the air can provide — and for still more examples of that magic at work, click on the links below.

More about atmospheric optics:

• Whoa! It's a quadruple rainbow!
• Optical illusions and light shows
• 'Tis the season of sky oddities
• 'Two suns' spotted in China

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Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered by email every weekday. You can also check out "The Case for Pluto," my book about the dwarf planet and the search for new worlds.

NASA's Curiosity rover has caught sight of its first solar eclipse from the surface of Mars — a slight bite taken out of the sun by the Martian moon Phobos, as seen from the rover's vantage point in Gale Crater on Thursday.

Curiosity's Mastcam imaging system captured this image of the partial mini-eclipse through a neutral density filter that reduced the sunlight to a thousandth of its natural intensity. After all, you wouldn't want Curiosity to blow out its camera on Mars, any more than you would want to damage your own eyes by staring at the sun without eclipse-viewing glasses. The bright spots in the darkness surrounding the sun may look like stars, but Keri Bean, a member of Curiosity's team at NASA's Jet Propulsion Laboratory, told me they're just "hot pixels" — flaws in the raw image data.

The rover was programmed to take hundreds of high-resolution images during the transit on Sol 37 of the mission, and eventually they could be transmitted and assembled into Curiosity's first eclipse movie. But that may take a while, due to the limited data-transmission bandwidth and the $2.5 billion mission's other priorities. Meanwhile, Curiosity has two more opportunities over the next couple of days to watch solar transits by Phobos and Mars' smaller moon, Deimos.

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More about Martian moons and eclipses:

• Watch an eclipse and a sunset on Mars
• Deimos passes over sun while rover watches
• Martian moons seen together for first time
• Phobos takes the spotlight

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Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other 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.

The sun sent out a flare powerful enough to disrupt radio communications over Europe today, along with an eruption of electrically charged particles that just might sweep past Earth's magnetic field in time to spark a Fourth of July show of auroral fireworks.

The M5.6-class solar flare, observed by NASA's Solar Dynamic Observatory at 6:52 a.m. ET (10:52 GMT), was almost powerful enough to cross over from the medium M-class category to an extreme X-class event, SpaceWeather.com's Tony Phillips noted. "A pulse of X-rays and UV radiation from the flare illuminated Earth's upper atmosphere, producing waves of ionization over Europe," he wrote.

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Such waves can spark bursts of radio static, as recorded by Rob Stammes in Norway and noted by the National Weather Service's Space Weather Prediction Center. "Radio blackout storms have been observed in the past 24 hours," the center reported on its Facebook page.

SpaceWeather.com says the solar eruption threw out a coronal mass ejection, or CME — not directly toward Earth, but in a southerly celestial direction. In the video above, you can see the solar material blurping downward and outward from a monster sunspot region known as AR 1515.

Phillips writes that the "south-traveling cloud could deliver a glancing blow to our planet's magnetosphere on July 4th or 5th." However, the Space Weather Prediction Center says the CME "is not expected to disturb the field during the forecast period."

The sun is in the midst of an upswing in its 11-year activity cycle, heading toward an expected maximum in 2013. Right now there are five sunspot regions on the sun's Earth-facing side, and two of them — 1513 and 1515 — are considered capable of sending out M-class flares. Such flares are generally associated with moderate disruption of radio communication and navigation systems. As for today's CME, the most likely effect will be heightened displays of the northern and southern lights.

CME or not, it looks as if it's a good week for auroras, judging from the pictures being sent in to SpaceWeather.com's real-time image gallery. The prime time for auroras generally begins at just about the time of night that the fireworks shows are finishing up. And there's more to see besides the fireworks: This happens to be a great week for seeing the full moon and Mars in sunset skies, or seeing Jupiter and Venus just before dawn. Sky and Telescope has the week's rundown.

So if you're out and about on the night of the Fourth, sit back and enjoy the fireworks — whether they're terrestrial or celestial in origin. And if you happen to snap a great picture of the northern or southern lights, please share it with us via our FirstPerson photo upload page. If we get some good ones, we'll pass 'em along after the Fourth.

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Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

A double-burst of solar particles sparked auroral lights over the weekend, as expected — but at least in some parts of the world, the colors were not what you'd expect. Instead of the typical greenish glow, observers reported seeing reds, pinks, violets and even blues.

"It's been many years since I saw the blue in our auroras, but Saturday night they came back," John Welling reported in a note accompanying the photo he posted to SpaceWeather.com.

Pinks, reds and blues also dominated the scene captured on camera early Sunday by Brad Goldpaint, from a vantage point above Oregon's Crater Lake. In an email, Goldpaint told me the opportunity came about "by pure coincidence."

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"Capturing this famous light show had been a dream of mine for several years, but I could not have imagined the lights showing up in my own backyard!" Goldpaint wrote. "After setting up near the Rim Village Visitor Center lookout area, I began to notice a faint band of moving light slowly making its way from behind the Watchman Tower, around 1:30 a.m. My camera began picking up bright pink bursts of light towards the north, with what also looked like unfamiliar vertical bands of light stretching upwards from the horizon. I quickly changed my camera’s white balance to confirm I was not picking up some random light pollution, or hallucinating in my drowsy state. Following additional exposures, I came up with the same amazing results. The magical shifting scene continued until sunrise, and like most days in the wilderness, I was awed and humbled by true nature personified."

The photo now graces Brad's portfolio at GoldpaintPhotography.com.

The colors of the aurora depend on the wavelength of the light emitted when fast-moving, electrically charged particles from the sun interact with different types of atoms and ions in Earth's upper atmosphere. If the particles hit mostly oxygen atoms, the light will be in the greenish-yellowish-reddish range. Collisions with nitrogen atoms produce the blue, purple and deep red hues.

The altitude of the auroral glow also affects the color: At altitudes between 60 and 120 miles (100 and 200 kilometers), the oxygen emissions tend toward the green side of the spectrum. At higher altitudes, you'll see more red. Blend all those colors, and you get a beautiful, wide-ranging palette.

The "Causes of Color" website provides a fuller spectrum of information. And speaking of a fuller spectrum, here are more of the weekend's colors, plus a bonus video:

More auroral glories:

• Northern lights blaze again on video
• Farewell to the northern lights
• Northern lights make for must-see TV
• Southern exposure for auroral lights
• Slideshow: The best of the northern lights
• Cosmic Log's auroral archive

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Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

For the second day in a row, the sun has sent a blast of electrically charged particles toward Earth — and according to SpaceWeather.com, that means we're in for a double shot of geomagnetic activity early Saturday. But not to worry: The most noticeable effect of the twin M-class blasts should be heightened auroral displays.

Both of the coronal mass eruptions, or CMEs, originated in a sunspot region known as AR1504, which is currently pointing in Earth's direction. AR1504 has been shooting off a series of flares in recent days, including an M1.2-class flare on Wednesday and an M1.5 today. None of the flares have approached the X-class level, which would have the potential for significant disruptions in power grids or satellite-based communication.

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SpaceWeather.com projects that the CMEs thrown off by those two flares will merge into one wave of particles that's due to hit Earth's magnetic field around 6:16 a.m. ET Saturday. The National Oceanic and Atmospheric Administration's Space Weather Prediction Center, meanwhile, predicts that the CME will arrive "late on 16 June." The prediction center noted that today's flare sparked a minor radio blackout and "has the potential" to produce more such storms.

Bottom line? Polar regions will have a better chance of seeing auroral lights over the weekend, although the midnight sun will put a damper on viewing in the north. If you catch a great auroral view, please consider sharing it with us via our FirstPerson upload page. In the meantime, keep a watch on SpaceWeather.com and the prediction center's Facebook page for updates — and feast your eyes on the imagery below:

More sun imagery:

• Your views and videos of the Venus transit
• Thrill to a sunspot's parting shot
• Graphic: Anatomy of a solar storm
• Cosmic Log archive on the sun

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Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

The transit of Venus may be finished until 2117, but videos and pictures of the phenomenon are continuing to gush all over the Internet. If you missed Tuesday's nearly seven-hour astronomical spectacle, you can get up to speed with a 39-second video from NASA's Solar Dynamics Observatory. If you've got a little more time, sit back and watch the three-minute version with a soaring soundtrack.

Another time-lapse video from the SDO team lasts just 12 seconds — but it shows one of the most scientifically significant phenomena surrounding the transit: the "Arc of Venus," an interval during which sunlight is refracted around Venus' disk, creating a "ring of fire." Close analysis of the refracted light can provide insights into the dynamics of Venus' mysterious atmosphere.

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The video also gives you a taste of the optical "black drop effect" that occurs when Venus crosses the edge of the sun's disk:

 

Here's a jaw-dropping view of Venus crossing the edge of the sun's disk from Japan's Hinode sun-watching satellite. You can make out the thin arc of sunlight refracted by the planet's atmosphere:

Over the past couple of days, we've run lots of pictures of Venus crossing over the sun's disk, but I can't pass up the opportunity to share some of the transit pictures that were shared by Cosmic Log correspondents. Here's a selection:

Thanks to everyone who submitted pictures, including Brian Helm, Adam Rybczynski, Jim Belfiore, Jacqueline Croasdale, Tommy Fortunato, Gary Brandon, Robert Schmidt, Steve Siedentop, Justin Van Hassel, Amy LeBaron, Xihui Zhang, Christopher Klug, David Hall, Jim Walsh, Bruce Korsmeyer (from Venus, Texas!), Steve Moulding, Kevin Palmer, Don Heaton, Brian Sinofsky, Tom Rejzek, Dave Holbrook, Sean Kinslow, Ameer Hassoun, John Melson, Veronica Hernandez, Jarra McGrath, Jason Heinitz, Howard Chan, Sam Stouffer, Eric Steele, Tim Baker, Dinar Dalvi, James Owen and Andrew Lee.

We won't have to wait until 2117 for the next astronomical photo op: Keep an eye out for coming attractions, highlighted by the Delta Aquarid and Perseid meteor showers of late July and mid-August.

More views of the Venus transit:

• Catch amazing views of Venus
• PhotoBlog: More photos of the Venus transit
• NASA's Venus Transit Observing Challenge on Flickr
• SpaceWeather.com's real-time image gallery
• Space.com: Transit of Venus gallery

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Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Thousands of scientists and skywatchers around the world have made detailed plans to monitor today's transit of Venus across the sun, but chances are that word of the last-in-a-lifetime event is just now sinking in for millions of just plain folks — so what's the big deal? And what's the best way to watch the transit?

We've had dozens of stories about Venus' day in the sun over the past few weeks, but for those of you who are just tuning in, here are the top 10 things to keep in mind about today's transit, whether your skies are sunny or completely socked in:

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1. Get the big picture: Venus comes between Earth and the sun five times in the course of every eight years, but because of the inclination of the planets' orbits, Venus usually misses passing over the sun's disk, as seen from Earth. In fact, that passing-over phenomenon occurs only twice in the typical person's lifetime. Two transits occur eight years apart, but each pair is separated by either 105.5 years or 121.5 years. We had a Venus transit in 2004, and we're having another one today. The next one won't come until 2117. So if you're into rare sky phenomena, today is as good as it gets.

2. Find out when and where: Venus' disk begins to pass over the left edge of the sun's disk a little after 6 p.m. ET, and makes a stately crossing that lasts until about 12:50 a.m. ET. (Of course, the sun will have set on the East Coast by then.) Some part of the transit will be visible from most locations on Earth — though you're out of luck if you're in eastern South America, western Africa, the Iberian Peninsula, Antarctica or the middle of the Atlantic.

The precise time when different edges of the planet's disk cross the sun's edge is actually a big deal. Those times vary by location on Earth, and the variations can be used to calculate dimensions and distances in the solar system. Today, so much is known about those dimensions that astronomers can predict the key times of the transit based on your location. To find out what you can see when, use the U.S. Naval Observatory's transit computer. 

3. Safety first: This is where I type out the bold-face warning that you should never gaze at the sun without proper eye protection. Sunglasses are not adequate. Neither are black plastic garbage bags, or film negatives. Unsafe viewing can damage your retinas. This video from "Astronomy Dave" Fuller explains the difference between proper and improper eye protection, not only for the transit, but for anytime you want to observe the sun: 

4. Use solar-filter glasses: If you've been looking forward to this transit, or if you observed the annular solar eclipse a couple of weeks ago, you probably already have your special sun-viewing glasses. But if you don't, you still might be able to find the glasses at a science-center gift shop, observatory or camera shop. Sheets of solar-filter material may be available at specialty shops, wherever fine telescopes are sold — but you should make sure that the material is considered safe for visual observations. No. 14 welder's glass also serves as a suitable solar filter. But No. 13? Not so much.

Because Venus' disk is only 3 percent as wide as the solar disk, it can be challenging to make out the dark spot without magnification. Paul Doherty, a staff physicist at San Francisco's Exploratorium, makes this comparison: Take a 7-inch-wide (15-centimeter-wide) paper plate, and draw a black dot on the plate that's less than a quarter-inch wide (5 mm). Then tack the plate onto a wall and back up 45 feet (15 meters). That black dot is what Venus will look like as it passes over the sun.

5. Make a pinhole projector: One way to avoid the "gazing at the sun" problem is to make a pinhole projector, which can be as simple as poking a hole in that paper plate and letting the sunlight shine through onto a shadowed piece of white paper. If you want to get fancier, you can build a projection box from shipping tubes, as the Exploratorium explains in this how-to guide. An alternate method would be to use a pinhole mirror or "reflected pinhole," as described in this Trinity College Cambridge guide.

6. Use binoculars or telescopes: You can use magnifying devices to get a bigger picture of the transit, but you have to know what you're doing. The best method is to put a specially made solar filter over the front aperture of your telescope, or over each of the front lenses of your binoculars. (You can also use a filter on one binocular lens and tape over the other lens to shut out the sunlight.) Some folks have carefully taped filter material from sun-viewing glasses over the front lenses of binoculars. But it's not safe to look through a telescope, viewfinder scope or pair of binoculars without a filter on the front end, even if you're wearing sun-viewing glasses. That's because sunlight will be concentrated by the instrument's lenses and potentially burn through the filter or even crack welder's glass.

7. Find an astronomer: You'll have the best experience if you're with a group that includes a knowledgeable amateur or professional astronomer. Science centers and national parks are likely to be hotspots for transit-viewing parties. Your local astronomy club is probably partying it up as well. Check out this worldwide directory of astronomy clubs, or this listing from the Astronomical League. If nothing else, call up the physics department of the closest college or university and find out what's going on.

8. See it on the Web: I'm guessing that most transit-watchers will be getting at least some of their looks via the Internet, particularly if the weather is lousy. Here's a listing of the webcasts that'll be available, including msnbc.com's simulcast of NASA's coverage:

• NASA TV and NASA EDGE at Mauna Kea: The Hawaii show starts at 5:45 p.m. ET.
• Exploratorium: The San Francisco science center's seasoned webcast team will be webcasting from Mauna Loa, Hawaii, starting at 6 p.m. ET.
• Univ. of North Dakota SEMS (in Alaska): UND's Tim Young says the road show and the chat will start cooking from Alaska at 5:45 p.m. ET. "It is one of two locations in the U.S. that will see the whole transit," he told me via email. "The other is Hawaii, and other groups are webcasting from there."
• Slooh Space Camera: Slooh starts its rock-solid webcast at 5:30 p.m. ET, featuring a dozen or more video feeds from Sweden, Norway, Australia, New Zealand, Hawaii, Arizona, New Mexico and other locales.
• Universe Today: Live shots from around the world with commentary from Bad Astronomer Phil Plait, Pamela Gay and other celebrity guests.
• Astronomers Without Borders: This show will be webcast from California's Mount Wilson Observatory.
• Coca-Cola Space Science Center: Columbus State University's science center in Georgia is offering pictures from the home base in Columbus, Ga., as well as from Utah, Mongolia and Australia. The webcast gets started at 5:30 p.m. ET.
• Mount Lemmon SkyCenter: The University of Arizona's astronomy center starts webcasting at 5 p.m. ET.
• Appalachian State University: The view from one of the Rankin Science Observatory's 11-inch telescopes will be streamed from Boone, N.C., during a public viewing event.
• Planet Hunters: The exoplanet-searchers will be carrying a webcast courtesy of the GLORIA Project, with live updates from Norway, Australia and Japan starting at 6:04 p.m. ET.
• Bareket Observatory: The webcast from Israel starts at 10:33 p.m. ET, which is around sun-up at the site.
• Kwasan Observatory: Watch a Japanese webcast from Kyoto. 
• Sky Watchers Association of North Bengal: SWAN's webcast from India gets under way at around 7:12 p.m. ET. 
• European Space Agency: ESA's Venus Transit Monitor will be transmitting images from Norway and Australia. Check out ESA's Transit of Venus blog for more.
• And still more... NASA's Venus Transit website links to more webcasts, as does Space.com and Sky and Telescope.

9. Soak in the science: Since the first transit of Venus was predicted in the 17th century, scientists have been taking advantage of the phenomenon. As I mentioned previously, measurements of the transit timing have been used to derive highly accurate estimates of the solar system's scale. Nowadays, transit observations play a key role in detecting and confirming the presence of planets around other stars. (NASA's Kepler planet-hunting mission has a Web page devoted to today's transit.) Spectral observations during the transit helped scientists determine the composition of Venus' atmosphere, and one of the big scientific projects this time around will use the "Arc of Venus" to unravel more of the atmosphere's secrets.

The Hubble Space Telescope is being enlisted to watch the moon for changes in the characteristics of reflected sunlight due to Venus' passage. Such observations may blaze a trail for analyzing the atmospheres of alien planets. ESA's Venus Express and Japan's Hinode sun-watching satellite will also be on the case. "The most spectacular images and movies should come from Hinode’s Solar Optical Telescope, which has by far the highest resolution of any solar instrument in space," said Bernhard Fleck, ESA's Hinode project scientist.

Even if you don't see a single picture from the transit, you've got to appreciate the role that the event has played over the centuries in planetary science. These two videos tell you more about the history of transit observations:

10. Take a picture: Astrophotographers will be having a heyday. On the International Space Station, NASA astronaut Don Pettit is aiming to take the first pictures of the transit of Venus from outer space, while shooters on Earth will be trying to catch the space station crossing the sun's disk in parallel with Venus, as they did in 2004. NASA has set up a Flickr page for a citizen-science opportunity called the Venus Transit Observing Challenge, which should appeal to lots of amateur photographers. But if you go out to take a snapshot, do it safely and surely. Here's how.

If you capture a great image, please share it with the rest of us. You can send us your pictures using our FirstPerson picture-uploading page. Here's wishing you clear skies and safe eyes!

Still more about the transit of Venus:

• VenusTransit app enables cosmic calculations
• Scientists spread out to watch Venus transit
• Venus transit may help spot alien planets
• Hubble may study rare transit of Earth in 2014

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Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.