NASA via AP
This image provided by NASA shows giant sunspot activity Thursday, Nov. 3, from a region on the sun that scientists are calling a "benevolent monster."
You have to hand it to the NASA scientist who came up with the name "benevolent monster."
Michael Theusner / Applied Optics
A third-order and fourth-order rainbow can be seen at the center of this photograph, taken from the countryside in northern Germany. The tertiary and quaternary rainbows appear on the sunward side of the sky, rather than the opposite side of the sky, as is the case for primary and secondary rainbows. This is the first picture of a quaternary rainbow in nature, and the second picture ever of a tertiary rainbow.
Look out, Double Rainbow Guy: You just might have a double-double freakout over this first-ever picture documenting a quadruple rainbow, which is the subject of a scientific paper in the journal Applied Optics.
Seeing two rainbows in the sky is a visual treat, leading a YouTube user named Paul Vasquez to rhapsodize to the point of tears. But three or four rainbows at the same time? That's the stuff of legend. Triple-rainbow reports have been bubbling up since the days of Aristotle, but only five reports from scientifically knowledgeable observers have been recorded during the past 250 years.
Not until this year has a triple rainbow or a quadruple rainbow been photographed and published in the scientific literature.
Such rainbows are more technically referred to as tertiary or quaternary rainbows. Like the better-known primary or secondary rainbows that Vasquez gushed over, these rare rainbows appear when sunlight bounces around the inside of a raindrop, is refracted and spread through a range of visible-light wavelengths and shines out to the observer as a multicolored arc in the sky.
The light beams that creates single or double rainbows take one or two bounces inside the raindrop, as shown in this diagram, and they're always visible in the part of the sky opposite the sun. In contrast, third-order and fourth-order rainbows require a triple or quadruple bounce, and appear on the sunward side of the sky, at angles of 40 and 45 degrees with respect to the sun.
That makes it well nigh impossible to capture all four rainbows in the same picture — and because some light is lost with each bounce, the third and fourth rainbows are incredibly faint. Even if there are raindrops in the right place, the effect is easily overwhelmed by the sun's glare.
Last year, U.S. Naval Academy meteorologist Raymond Lee and a colleague, Philip Laven, laid out a prediction for the conditions that would produce third-order rainbows, and they challenged rainbow-chasers to go out and find one. Among the requirements: dark thunderclouds, and either a heavy downpour or a rainstorm with nearly uniform rain droplets. If the sun broke through the clouds under these conditions, it could project a dim tertiary rainbow against the dark clouds nearby, they said.
Michael Grossmann / Applied Optics
Michael Grossmann's photograph of the skies over Kampfelbach during an evening rain shower is at left, with two points marked A and B as a reference for image orientation. A processed version of the image is at right, revealing a faint tertiary rainbow between the white arrows.
Some experts thought it'd be impossible to make out the rainbow, but amateur rainbow-chasers rose to the challenge. On the evening of May 15, the required conditions came together for Michael Grossman, an observer in Kampfelbach in southwestern Germany. He turned toward the sun and started snapping pictures where the tertiary rainbow should have shown up.
"It is really exaggerated to say that I saw it, but there seemed to be something," he said in an Optical Society news release.
When the pictures were put through contrast expansion and unsharp masking, the faint arc of the tertiary rainbow came through.
Grossmann's feat made an impression on another German rainbow-chaser, Michael Theusner, and he had his camera at the ready on the evening of June 11 when a rainstorm came toward his home in Schiffdorf in northern Germany. Here's how he described the event to me in an email:
"Actually, the chasing started as a normal storm-chasing effort. I was on my way home when the storm front approached from the southwest. A nice shelf cloud had formed at the base of the storm, and I hurried home to fetch my camera (Canon 40D + Canon EF-S 17-55 mm lens) to take some photos. Then I went to a nearby field road, where you have an unobstructed view of the sky. However, when I finally reached that location, the shelf cloud had largely disappeared. So I was disappointed at first, but hoped for the rear of the storm to show some interesting cloud features. So I waited while heavy rain was falling.
"When the sun started to come out, I realized that the situation was just like the one Michael Grossmann had had when he took the first photo of the third-order rainbow. I had read about his observation on June 3 in a German Internet discussion forum for atmospheric phenomena — only about a week earlier. Thus, I tried to catch that rare rainbow, too.
"I had asked Michael Grossmann in the forum whether or not he had taken several images so as to stack them to increase the signal-to-noise ratio — a technique well known to amateur astronomers like me. Using that technique, it is possible to increase the visibility of faint signals in images. Unfortunately, he had not. I decided to use that technique to increase the chances to record the third-order rainbow. I took several image series until the rain stopped at my location. I did not see that rainbow visually.
"Back home I started processing, and already the first image series that I took when the sun brightly lit the raindrops showed the third-order rainbow! I was excited and started converting and stacking the order image series. One of them looked strange, however. Another rainbow was visible just to the third-order bow's right. Fainter, but still visible. I checked the Internet for higher order bows and quickly realized that that image series likely showed the fourth-order rainbow. I roughly calculated the radius of that bow and it matched the predicted location of the quaternary bow.
"I was stunned, as I discovered that this was very likely the very first image in the world to show this rainbow."
Theoretically, it's possible to have a quintuple or a sextuple rainbow, but the optical geometry of the bounces within the raindrop is such that the fifth- and sixth-order rainbows would be overwhelmed by the light from the first- and the second-order rainbows. "So it may never be possible to image those," Theusner said.
The research papers describing the observations, and providing guidance for future rainbow-chasers, appear in a special issue of Applied Optics. The bottom line is that the phenomenon is too dim to see with the naked eye, "with the possible exception of very rarely combined circumstances of favorable illumination, background and the strength of rain," Grossmann said. You'd have to point your camera in the right direction without actually seeing the bow, and then do some heavy-duty image processing. But Grossmann and Theusner have proven that it can be done. And for Lee, the meteorologist who issued the original challenge, that's like a ray of sunshine.
"It was as exciting as finding a new species," he said.
More about atmospheric phenomena:
Here are the three papers published this week in the Applied Optics, the journal of the Optical Society:
Connect with the Cosmic Log community by "liking" the log's Facebook page or following @b0yle on Twitter. You can also add me to your Google+ circle, and check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
Amazing video of beautiful Aurora Borealis shot in Finnish Lapland in the winter of 2011.
It's been a banner year for auroral displays, as seen from Earth as well as from space. This time-lapse view of the northern lights in Finnish Lapland has to rank as one of the year's more stellar compilations. The video was produced by Flatlight Films as a travel come-on for Visit Finland. The views were captured from several locations, using DSLR cameras with remote pan/tilt heads. For the full effect, go full-screen HD on the YouTube video (or the Vimeo version).
If this puts you in the mood to visit Finland, check out Travel+Leisure's recommendation for a romantic hotel in Lapland (which also made Concierge.com's list of off-the-grid resorts. But if you'd rather watch the northern lights from your computer chair, check out SpaceWeather.com's aurora gallery or the Canadian Space Agency's AuroraMAX webcam. Come to think of it, you can check out these links as well:
The music for the video is by the Finnish group CC33. Tip o' the Log to Bad Astronomy's Phil Plait and Universe Today's Nancy Atkinson.
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
NASA
Many auroral displays appear green, but sometimes, as in this Sept. 26 image from the International Space Station, other colors such as red can appear.
"Red sky at night, sailor's delight": That's one of the oldest sayings in the book when it comes to weather prediction, but this picture adds a new twist. The red sky is an aurora, seen from above by astronauts on the International Space Station. And the weather that's causing this phenomenon is space weather from the sun.
Auroras arise when electrically charged particles from the sun interact with atoms in the upper atmosphere, sparking emissions of light at various wavelengths. The displays are most likely to be visible around Earth's magnetic poles, where the interaction is strongest. The sun has been going through an upswing of activity over the past couple of months, which has generated a colorful series of northern and southern lights.
North or south, the most common shade of auroral light is green. That's the wavelength that's typically emitted when solar particles mix it up with oxygen atoms. But if there are lower-energy collisions with oxygen atoms or nitrogen atoms, the emissions edge toward the reddish end of the spectrum. That's what's happening in this picture, captured on Monday. You should be able to make out the space station's solar panels toward the upper left corner of the photo.
Space weather can create disruptions for satellite communication systems as well as electric grids on Earth, but so far the most noticeable effect from this year's solar storms has been a string of glorious auroras. We weathered the latest geomagnetic storm overnight, and SpaceWeather.com is offering up a selection of snapshots — including this red-and-green stunner from Russia's Kola Peninsula.
To learn more about the colors of the aurora, check out this "Causes of Color" explanation. And if you live in northern or southern climes, there's always a chance of seeing the lights for yourself. Last night, the aurora was visible from Minnesota, Germany and Poland in the north, as well as New Zealand in the south. The University of Alaska at Fairbanks provides this handy-dandy online guide to aurora-watching.
More auroral glories:
A time-lapse video from the International Space Station features a flyover of the southern lights.
It's been a great summer for auroral displays, and especially from space. Here's a time-lapse video showing the International Space Station's passage over the southern lights on Sept. 11. The tour begins with the station arcing southeast over eastern Australia, passing over New Zealand and then heading northeast in its inclined orbit. There's a dense cloud cover over Earth's surface, but that just makes the ripples of green light stand out even more.
The 26-second video was compiled from about 16 minutes' worth of photo-snapping by the space station's crew, from their vantage point in the orbiting outpost's Cupola observation deck. (Make sure you're watching the PhotoBlog wide-screen version.)
North or south, auroral lights are sparked when electrically charged ions from the solar wind interact with atoms in the upper atmosphere. In an advisory about the video, NASA notes that green is the most common auroral shade, coming from the light emitted from emitted oxygen atoms. Flashes of red show up here and there. You can also see a golden glow visible along the rim of the atmosphere, just above the curving horizon. That airglow is caused by the excitation of atoms by ultraviolet radiation.
For a big assortment of Earth views from NASA, check out the Gateway to Astronaut Photography of Earth, and for auroral views feast your eyes on SpaceWeather.com's Aurora Gallery. Here are a few more must-see examples of our Earth at night, as seen from the International Space Station:
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
Science educator James Drake assembled this time-lapse video of Earth at night from International Space Station imagery. Pacific Ocean and continues over North and South America before entering daylight near Antarctica. (Credit: Infinity Imagined)
This must-see video condenses the International Space Station's night flight over Earth into 60 seconds, courtesy of science educator James Drake. He downloaded a series of 600 pictures from the Gateway to Astronaut Photography of Earth — a voluminous archive of a half-century's worth of imagery from the space station and NASA's manned spacecraft. Then he assembled them into the clip you see here using VirtualDub software.
The flight to the sunrise begins over the Pacific Ocean and zooms at an altitude of about 220 miles (350 kilometers) past Vancouver Island and Victoria, the Pacific Northwest and the American Southwest, Texas and Mexico, Central and South America. The highlights to watch for include constellations of city lights, lightning flashes in the clouds, the stars whirling in the night sky above, the faint brown-yellow atmospheric airglow that rims the eastern horizon, and the glorious dawn at the end.
For more of Drake's work, check out his Infinity Imagined website.
More amazing imagery from orbit:
Tip o' the Log to Fraser Cain at Universe Today.
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
Sylvain Serre
Sylvain Serre took this picture of the northern lights on Sept. 3 from the village of Ivujivik in Quebec.
Our planet has managed to dodge the potential ill effects from a string of solar storms over the past couple of weeks ... while still enjoying the wonders.
The region on the sun's disk known as sunspot 1283 has been spouting off with one flare after another, earning it the title of "Old Faithful" among solar physicists. Old Faithful has thrown off several coronal mass ejections, which are outbursts of solar particles that stream through the solar system at speeds of a million miles per hour. If a powerful outburst hits Earth's magnetic field were to hit just wrong, that could cause problems for satellite operations, communication links and electrical grids.
One of the most famous disruptions in recent times was the Hydro-Quebec blackout of 1989, caused by a huge disturbance in space weather. Back in 1859, an even bigger solar storm flashed through daylight skies and set telegraph wires sizzling. Some observers say such an event would blow out civilization's fuses if it happened today, but experts downplay the chances of seeing a solar doomsday anytime soon.
Solar activity is definitely on the upswing toward an expected maximum in 2013, but so far, we haven't seen any direct hits on the magnetosphere. Instead, we're seeing a series of glancing blows that have set off beautiful auroral displays in the upper atmosphere, like the show that photographer Sylvain Serre captured from northern Quebec on Sept. 3.
"For the first time of the season, there was a clear sky in the northern village of Ivujivik (the highest point in Quebec)," Serre wrote in a note to SpaceWeather.com. "So I went outside with a friend to take a little walk and to get more familiar with the landscape around here. Fortunately, the northern lights were very bright, dense and colorful."
For the camera buffs out there, Serre used a Canon EOS 5D Mark II with a 16-35mm lens set at f/2.8 and 4000 ISO, at exposures ranging from 10 to 25 seconds. Check out the SpaceWeather gallery or Serre's website for still more thrilling views of the northern lights.
Ron Garan / NASA via Twitpic
NASA astronaut snapped this picture of an auroral display from the International Space Station and sent it down to Earth via his Twitpic account on Monday.
For a completely different perspective on the aurora, feast your eyes on this view of the southern lights, as seen by NASA astronaut Ron Garan from the International Space Station over the weekend. The space station's Italian-built Leonardo storage module is visible in the foreground.
Garan has had the good fortune to see a wide range of glorious phenomena during his time in orbit — including the Perseid meteor shower, as viewed from above, and an astronaut's-eye view of Atlantis' historic descent to the last-ever space shuttle landing. He's been sharing these and other visual treats via his Twitpic account as well as his Fragile Oasis website.
Garan promises that better pictures of the aurora are "coming soon." But those pictures might have to wait until after he lands back on Earth on Friday aboard a Russian Soyuz spacecraft. "I have thousands of pictures for Twitter when back from space," he wrote on Monday. "You've seen just the tip of the iceberg."
As a parting shot, here's the final installment of Garan's "Cupola Corner" video series with fellow NASA astronaut Mike Fossum:
With the sun rising outside their window, NASA astronauts Ron Garan and Mike Fossum reflect on their 100 shared days on the International Space Station.
More views of auroras and space sights:
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
NASA / JPL-Caltech / Cornell / ASU
NASA's Opportunity rover produced this mosaic view of its own tribute to the victims and the survivors of the 9/11 terror attacks on Sept. 11, 2011. The component bearing the image of the flag was fashioned out of aluminum salvaged from the World Trade Center towers and serves as the cable guard of a tool on NASA's Mars Exploration Rover Opportunity. Two separate cameras on Opportunity recorded exposures that were combined into this view.
Last week we told the story of how a 9/11 memorial got to Mars aboard NASA's Opportunity rover — and aboard its twin, the Spirit rover, which was put to rest this year after succumbing to the Martian winter. Today NASA released this photographic mosaic highlighting Opportunity's piece of 9/11, sent back to Earth on the 10th anniversary of the terror attacks.
The color image at the center came from Opportunity's panoramic camera. It's easy to spot the U.S. flag on the aluminum cable shield that was fashioned out of metal salvaged from the ruins of New York's World Trade Center and attached to the rover's robotic arm. The black-and-white view surrounding the color picture was produced by the rover's navigation camera, which can capture a wider view.
Scientists originally planned for Opportunity to execute a three-month mission at Mars — but more than seven and a half years after it landed, the six-wheeled robotic explorer is still hard at work, studying the 14-mile-wide Endeavour Crater. Neither dust storms nor sand traps have managed to defeat the rover, which is why it's so fitting that a little red-white-and-blue piece of the machine commemorates America's resilience in the post-9/11 world.
More about Mars and 9/11:
NASA / JPL-Caltech / SSI
The Cassini spacecraft captured this view of five Saturnian moons, plus the planet's rings, in this image from July 29. Janus is on the far left. Pandora orbits between two of the rings near the middle of the image. Brightly reflective Enceladus appears above the center of the image. Rhea is bisected by the image's right edge, and Mimas can be seen beyond Rhea, just to its left. Saturn itself is not visible in this view ... only its rings.
Five Saturnian moons are clustered around the giant planet's rings in this amazing view from the Cassini orbiter, captured on July 29 from a vantage point just above the ring plane. Rhea, which is poking in from the far right side of the frame, is the moon closest to the camera, at a distance of 684,000 miles (1.1 million kilometers). That moon is 949 miles (1,528 kilometers) across. The smaller moon Mimas looks as if it's edging up right beside Rhea, but it's actually more than 400,000 miles farther away. The bright moon Enceladus, which spouts geysers of water ice, shines above and beyond Saturn's rings.
Fifty-mile-wide Pandora, a shepherd moon and the smallest of the five satellites seen in this picture, is nestled within Saturn's rings, between the A ring and the thin F ring near the middle of the image. The irregular moon Janus is at far left. These five are just a small part of Saturn's huge chorus of 62 known moons.
The bus-sized Cassini probe was launched back in 1997 and has been sending pictures back from Saturn and its moons since 2004, but it's still going strong. For more from the Cassini mission, check out the imaging team's home page, NASA's Cassini website and our own slideshow of the mission's greatest hits. Here's a little bit extra about each of the moons seen in this picture:
NASA / SDO / LMSAL / GOES
An X2.1-class solar flare erupts from the sun in this image, captured in extreme ultraviolet by NASA's Solar Dynamics Observatory on Sept. 6.
An unusually strong X2.1-class solar flare blasted out from the sun on Tuesday, but experts say the outburst shouldn't impact Earth significantly — unless you're a fan of the northern lights. Auroral displays could be somewhat brighter on Friday, when a wave of electrically charged particles ejected by the blast is expected to deal a glancing blow to Earth's magnetic field.
The flare from sunspot 1283 peaked at 6:20 p.m. ET, according to the science team for NASA's Solar Dynamics Observatory, which observed the event in ultraviolet and X-ray wavelengths. X-class flares are the most powerful types of events, capable of triggering radio blackouts. This flare was associated with a coronal mass ejection, an eruption of a giant cloud of solar material. If such an ejection hits our planet's magnetic field just wrong, it can disrupt electrical grids and satellites. Fortunately, most of the material ejected on Tuesday will go far above the planet, space-weather forecasters say.
A less energetic flare was sighted in the same region of the sun's disk earlier in the day. The recent upswing in solar activity suggests that the sun is on its way toward the peak of its 11-year cycle, after an unusually long quiet stretch. Experts expect the peak to come in 2013.
More about the power of the sun:
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