Spring Unveils Saturn's Hexagon [720p]

This movie from Cassini, made possible only as Saturn's north pole emerged from winter darkness, shows new details of a jet stream that follows a hexagon-shaped path and has long puzzled scientists.

The hexagon was hidden in darkness during the winter of Saturn's long year, a year that is equal to about 29 Earth years. But as the planet approached its August 2009 equinox and signaled the start of northern spring, the hexagon was revealed to Cassini's cameras. This is the first time the whole hexagonal shape has been mapped out in visible light by Cassini, and these images show unprecedented details of Saturn's high northern latitudes. The hexagon was originally discovered in images taken by Voyager spacecraft in the early 1980s. Since 2006, the Cassini Visual and Infrared Mapping Spectrometer (VIMS) instrument has been observing the hexagon at infrared wavelengths, but at lower spatial resolution than these visible light images.

Three large mosaics were used to create this three-frame movie. The mosaics used dozens of images and the constituent images were projected into polar projections to provide a complete view of the hexagon. The mosaics used in this movie do not show the region directly around the north pole because it had not yet fully emerged from the polar winter night. Seams between the images are visible in the third frame of the movie because the observation geometry in those images made removal of the seams difficult.

The six-sided shape remains a mystery. Scientists think the hexagon is a meandering jet stream at 77 degrees north latitude, but they don't know what controls the path the stream takes. These images also show new phenomena for scientists to decipher, such as waves that can now be seen radiating from the corners of the hexagon where the jet takes its hardest turns. These images confirm the presence of a multi-walled structure in each of the hexagon's six sides, and the structure now can be seen extending to the top of Saturn's cloud layer. The images show that the inside of the hexagon is darker than the outside. The new images also show a large spot inside the hexagon that could be related to a dark spot seen inside the hexagon in 2006 in an image taken by Cassini's VIMS instrument. An earlier Voyager mosaic showed a large spot outside the hexagon. That spot existed at least until 1991 before disappearing into the long winter polar night.

Images from Voyager and from ground-based telescopes suffered from poor viewing perspectives. In late 2006, Cassini's VIMS camera imaged the region in the thermal infrared wavelength, showing the hexagon in false color. Multiple images acquired by the VIMS instrument over a 12-day period showed that the feature is nearly stationary and is likely an unusually strong pole-encircling planetary wave that extends deep into the atmosphere. Scientists had speculated that a large vortex seen outside the hexagon during the Voyager observations exerted forces on the jet stream making it adopt a hexagonal pattern in a manner similar to how jet streams on Earth divert around high-pressure systems. However, in these new images, the vortex is notably absent while the hexagon persists almost 30 years after it was first seen.

Credit: Credit: NASA/JPL/Space Science Institute

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  Science & Technology

[FletcherHabit]

When does that probe land scheduled to arrive mid 2011 i forget exactly.. anybody know what im talking about?

[djxatlanta]

- The Huygens probe landed on Titan in January 2005 and took some incredible photos on the way down. A year or two ago I posted some movies of the landing produced by ESA compiled from the descent imagery. Pretty cool stuff. The next lander mission is the Curiosity rover to land on Mars in August 2012. Then a Russian mission will land on Phobos sometime in 2012 to collect rock samples to return to Earth.

[argodell]

Its funny how the biggest mystery in the solar system has had almost no media or documentary coverage to speak of.

[djxatlanta]

- there are plenty of interesting phenomena at Saturn and its rings and moons. Truth be told, the polar hexagon has been discussed in scientific circles for almost 30 years, but atmospheric fluid dynamics doesn't have the flashy zing in documentaries compared to the more media-friendly ice geysers on Enceladus, the Earthlike geology and weather on Titan, the two faces of Iapetus and of course those gorgeous rings!

[Felhek Lehrian]

what worries me is that nasa discovered it in the 80s, and never told us about it till now. i wonder how many things they know, but they're not telling us right now.

Think about it.

[djxatlanta]

- actually, yes, it was announced back in 1980 and 1981. As a kid, I followed the Voyager space program quite a bit through the 70s and 80s, and I very much remember when it was discovered. I haven't seen all the research, but it's a completely natural atmospheric effect. I've seen some videos where they simulate Jupiter's and Saturn's atmospheres with spinning circular tanks, and they can re-create Saturn's hexagon and Jupiter's Great Red Spot in the laboratory.

[LilyLava]

I blinked and missed it.

[rixille]

He is wrong about pyramids.. There is a four sided shape below it, thus we debunked his conspiracy theory.

[ew0054]

Two beers in the fridge? I smell a conspiracy!

[sunshynegrll]

Oh my *god* some of you people are so dumb.

[Jon Britton]

"Pyramids are just three dimensional representations of a triangle which is a three sided geometric shape."

If these ancient pyramids were triangular pyramids (with a triangular base), not square pyramids (with, you guessed it, a square base) then would sound marginally less insane.

[NoneyaBizziness]

I go further... but won't waste the time here. we are limited in the 3d... it's really a mess... if you do salvia or any other drug that takes you out of this dimension you will figure it out.

science.... I just laugh. yes in 3d they find out things about us on earth. but nothing about what is really happening.

only though our consciousness do we find answers. I'm out.

[scionofwar]

So, you found the number 3 in several things. Good work.

Did you know that we have two eyes, two nostrils, two ears?! Gasp, and guess what, yes, we have two legs! Crazy. Now here's where it gets really interesting. Einstein's equation e=mc2 has a 2 in it! Wait, it goes deeper, you'll soon find 2 in everything, not just your anatomy or world-changing equations. There's two beers in the fridge. There's two kids at the park.

Just a coincidence?

[Darkskies Siren]

oh good to know the mystery is solved but they still call it a mystery. I can make a talking unicorn in my basement, doesn't mean much... The fact is the Saturn hexagonal formation requires more study... refer to nasa's own website, and you'll see that there are still many unanswered questions.

[NoneyaBizziness]

Saturn the sixth planet from the sun has a geometric figure of a six sided hexagon on its pole. Now consider this coincidence.

The Earth is the third planet from the Sun and has ancient Pyramids all over it. Pyramids are just three dimensional representations of a triangle which is a three sided geometric shape. Also we believe these pyramids were built by humans who live in a three dimensional world (3 again). Just a coincidence?

[Lucio Flavio]

2 seconds?