Tag: Juno

Cool image time! Citizen scientist Gerald Eichstädt, using twelve Juno images, has compiled a short gif movie that shows a tiny amount of cloud movement.

I think this is one of the first times Juno has show us even a tiny bit of cloud evolution, information that is essential for gaining a true understanding of Jupiter’s slightly less than 2000 mile deep atmosphere. To see it, go to the link. As Eichstadt notes, “Individual images are noisy, but we see cloud motion.”

When you watch, zoom in on the upper right quarter. This is the area that the cloud motion is seen best.

The uncertainty of science: New results from Juno reveal that the jet-stream-type bands visible on the surface extend down to 1,900 miles, deeper than expected. Below that,

…the planet rotates nearly as a rigid body.”This is really an amazing result, and future measurements by Juno will help us understand how the transition works between the weather layer and the rigid body below,” said Tristan Guillot, a Juno co-investigator from the Université Côte d’Azur, Nice, France, and lead author of the paper on Jupiter’s deep interior. “Juno’s discovery has implications for other worlds in our solar system and beyond. Our results imply that the outer differentially-rotating region should be at least three times deeper in Saturn and shallower in massive giant planets and brown dwarf stars.”

Scientists had not expected the atmosphere go that deep.

Other results show that that the gas giant’s complex polar regions are surprising as well.

Its north pole is dominated by a central cyclone surrounded by eight circumpolar cyclones with diameters ranging from 2,500 to 2,900 miles (4,000 to 4,600 kilometers) across. Jupiter’s south pole also contains a central cyclone, but it is surrounded by five cyclones with diameters ranging from 3,500 to 4,300 miles (5,600 to 7,000 kilometers) in diameter. Almost all the polar cyclones, at both poles, are so densely packed that their spiral arms come in contact with adjacent cyclones. However, as tightly spaced as the cyclones are, they have remained distinct, with individual morphologies over the seven months of observations detailed in the paper.

“The question is, why do they not merge?” said Adriani. “We know with Cassini data that Saturn has a single cyclonic vortex at each pole. We are beginning to realize that not all gas giants are created equal.”

I am always baffled when scientists are surprised at the infinite variety of the universe. It is absurd to assume Jupiter and Saturn would be alike, especially considering the history of solar system exploration since the dawn of the space age. Since the first probe got a close look at the Moon, every single new object observed has been completely different from every other previously observed object. Every object has been unique. None have been the same.

Jupiter should be no different. And I guarantee that the next fifty gas giants we finally get a close look at out there among the stars will be as different from each other as they are from Jupiter. It is going to take a lot of exploration for us to finally get a handle on the overall patterns of planetary formation.

Cool movie time! Using Juno images, a citizen scientist has created a short movie showing two complete rotations of Jupiter’s south polar regions. I have embedded the movie below the fold. It is definitely worth watching. As he notes,

Due to Jupiter’s low axial tilt we never see more than roughly one half of the area around the poles in sunlight at any given time. However, it is interesting to see what Jupiter’s polar regions would look like if things were different and a big area around the poles was illuminated. This rotation movie shows what Jupiter’s south polar region would look like near the time of southern summer solstice if Jupiter’s axial tilt was much greater than it is, i.e. comparable to Saturn’s axial tilt.

He also notes the puzzling fact that, though Jupiter and Saturn are both gas giants, unlike Saturn Jupiter does not have a vortex at its poles. In fact, he points out how none of Jupiter’s storms are centered at the pole. Why one gas giant should have such pole-centered vortexes while another does not is a big mystery that illustrates how very little we know about planetary formation and evolution.

The two rotations also do not show any changes in the storms, not because they aren’t changing but because the images used were taken over too short a time span to show this.
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Cool image time! The image above, reduced in resolution to post here, was taken during Juno’s ninth close fly-by of Jupiter in late October, and shows one particular storm swirl in the gas giant’s southern hemisphere.

The Juno team today highlighted an image taken during this fly-by of Jupiter’s entire southern hemisphere, but I find this close-up more interesting. Be sure to check out the full resolution version. It appears to me that the white swirls have risen up above the gold and blue regions, casting shadows down upon them.

Unfortunately, I cannot tell you the scale of this storm, as the release does not give any details, including where in the full hemisphere image it is located. I suspect, however, that it is large enough to likely cover the Earth.

Both the full hemisphere image and the image above were processed by citizen scientists Gerald Eichstädt and Seán Doran.

Another citizen scientist who goes by the moniker of mesno has uploaded a spectacular 3D anaglyph of one of Juno’s images of Jupiter.

I could post it here, but I’d have to reduce its resolution, and I don’t think this will work well. If you have red-blue anaglyph 3D glasses the image does a great job of showing the differing vertical heights of Jupiter’s many horizontal bands, especially since it exaggerates the vertical scale significantly to bring out these differences.

Mesno has done three other anaglyphs. Check them out. The image of the Great Red Spot really shows how this is a vast whirlpool boring deep into Jupiter’s atmosphere.

Citizen scientist Gerald Eichstädt has done it again, assembling and enhancing the images taken by Juno in its September 1, 2017 fly-by of Jupiter to produce a spectacular movie, embedded below.

In his words,

This animation reconstructs the two and a half hours from 2017-09-01T20:45:00 to 2017-09-01T23:15:00 in 125-fold time-lapse with 25 frames per second, using 20 raw JunoCam images. JunoCam is Juno’s optical and near infrared Education and Public Outreach camera.

Trajectory data are retrieved from SPICE kernels via the NAIF spy.exe tool. The NAIF/SPICE environment is the way NASA provides spacecraft navigation data.

The movie shows Jupiter in a heavily enhanced way, in order to reveal detail.

Some of the raw images cover only part of the area required to render a still of the movie. In these cases, you’ll see the border of the raw image.

Each image is rendered into a short scene. The scences overlap and are blended.

Rendering the movie took about five days. Any shortcomings of the movie are a result of imperfect image processing.

Gerald Eichstädt at the Juno image site has produced the first attempt to assemble a movie of Juno images of the same area on Jupiter in order to show its changing weather.

JunoCam has been seeing this scene about six times from very different perspectives between about 2017-09-01T22:03 and about 2017-09-01T22:19, hence a over a little more than 15 minutes.

This animation is a first attempt to reproject the six images to a similar common perspective in order to reveal some dynamical information.

An movie covering only 15 minutes won’t show much change, but it is a start. He also notes that in making the different images match up he likely introduced some artifacts that are not real.

The uncertainty of science: Scientists analyzing the data sent back by Juno have found that the system for generating Jupiter’s aurora does not appear to be same as the process that creates auroras on Earth.

The science here is a bit complicated. Suffice it to say that Jupiter’s aurora seems produced by a much more complex process, which actually should not have surprised anyone, considering how much larger Jupiter is and more powerful its magnetic field.

Cool image time! The raw images taken during Juno’s seventh close fly-by of Jupiter have been released. The image on the right, reduced in resolution to post here, was reprocessed by Gerald Eichstädt and shows the gas giant’s south polar region.

It is worthwhile comparing this with previous south pole images, as well as other images from this fly-by reprocessed by Eichstadt. I want to know whether anyone can identify specific storms and show how they have changed over time. Unfortunately, Juno’s orbit is large, and so it only drops in close every 53 days, allowing for these storms to change a great deal, and thus making it more difficult to link images of the same changing storm. Moreover, the images don’t necessarily show the same longitudes on Jupiter, making this even more difficult.

Nonetheless, to gain a real understanding of Jupiter’s atmosphere will require a clear understanding of the pace in which its storms and atmosphere change. These images might give us our first glimpse of this process.

Using two Juno images of the same area, taken at slightly different times, scientists have produced what might be the first very short gif animation showing the changing circulation patterns in Jupiter’s atmosphere.

The animation is only two images long, so in a sense it isn’t a movie but a blink comparison. Moreover, the difference in circulation patterns between the two images is not strongly evident, partly because the two images have different resolution and somewhat different lighting. Nonetheless, this animation foretells what will should become possible with time, as Juno’s mission continues. Eventually its images will show the changes in the gas giant’s storms.

Cool image time! The Juno image on the right, cropped to show here, focuses in on one of Jupiter’s mid-sized storms near its high northern latitudes and just on the edge of the chaotic polar region.

This storm is a long-lived anticyclonic oval named North North Temperate Little Red Spot 1 (NN-LRS-1); it has been tracked at least since 1993, and may be older still. An anticyclone is a weather phenomenon where winds around the storm flow in the direction opposite to that of the flow around a region of low pressure. It is the third largest anticyclonic oval on the planet, typically around 3,700 miles (6,000 kilometers) long. The color varies between red and off-white (as it is now), but this JunoCam image shows that it still has a pale reddish core within the radius of maximum wind speeds.

Be sure to take a look at the full image, which provides a bit of context.

Juno has successfully completed its sixth close fly-by of Jupiter, this time dipping down to within 2,200 miles of the gas giant’s cloud tops and about 5,600 miles above the Great Red Spot.

All science instruments worked flawlessly, according the NASA press release. Images should become available in the next few days.

The next close fly-by will occur in September.

Cool image time! On the right is a cropped and reduced resolution section from this image from Juno. It shows the top of some of Jupiter’s clouds, swirling about chaotically.

What I find most fascinating is how this image reveals the different elevations of some of these cloud belts. The swirling clouds on the left and bottom of the image are clearly higher than the dark areas to the top and right. They are in fact casting their shadows on those lower cloud-tops.

To really understand the interactions taking place here, however, will require satellites capable of continually tracking these clouds over time. Unfortunately, Juno cannot do this. Though it will provide us periodic snapshots of specific areas, its long 53-day orbit means that it will not return to view the same areas very frequently. Making movies of the evolution of these clouds will be difficult, if not impossible.

Cool image time! The image on the right, reduced to post here, shows Jupiter’s south pole and much of its southern hemisphere. It was taken during Juno’s last orbital fly-by of the gas giant’s cloud tops last week, and has been enhanced by Fevig-58, an ordinary citizen who downloaded the raw image and then uploaded his enhanced version to the Juno website.

It is definitely worthwhile taking a close look at the full resolution image. At the top its shows the horizontally banded Jupiter at equatorial- and mid-latitudes that has been that planet’s familiar face for centuries. In the middle is the transitional region from those horizontal bands to the chaotic polar regions. And at the bottom is the pole, where there the storms appear to follow no pattern and form a mish-mash.

One thing about Jupiter’s pole. It appears very different than Saturn’s. While I am certain they will find a vortex of some kind there, so far there is no indication of a coherent jet stream, as seen by Saturn’s hexagon. This once again demonstrates the one unbroken rule of planetary science that has been found with every planetary mission to every planetary body, whether they be pebbles, asteroids, dwarf planets, gas giants, or moons: Every single one of them is different and unique. They might fall into a single category, say gas giants, but each has its own unique features that make it different from every other member of that category.

The Juno science team today released their first research results since the spacecraft entered orbit around Jupiter in July 2016.

“Although many of the observations have terrestrial analogs, it appears that different processes are at work creating the auroras,” said SwRI’s Dr. Phil Valek, JADE instrument lead. “With JADE we’ve observed plasmas upwelling from the upper atmosphere to help populate Jupiter’s magnetosphere. However, the energetic particles associated with Jovian auroras are very different from those that power the most intense auroral emissions at Earth.”

Also surprising, Jupiter’s signature bands disappear near its poles. JunoCam images show a chaotic scene of swirling storms up to the size of Mars towering above a bluish backdrop. Since the first observations of these belts and zones many decades ago, scientists have wondered how far beneath the gas giant’s swirling façade these features persist. Juno’s microwave sounding instrument reveals that topical weather phenomena extend deep below the cloudtops, to pressures of 100 bars, 100 times Earth’s air pressure at sea level.

“However, there’s a north-south asymmetry. The depths of the bands are distributed unequally,” Bolton said. “We’ve observed a narrow ammonia-rich plume at the equator. It resembles a deeper, wider version of the air currents that rise from Earth’s equator and generate the trade winds.”

Juno is mapping Jupiter’s gravitational and magnetic fields to better understand the planet’s interior structure and measure the mass of the core. Scientists think a dynamo — a rotating, convecting, electrically conducting fluid in a planet’s outer core — is the mechanism for generating the planetary magnetic fields. “Juno’s gravity field measurements differ significantly from what we expected, which has implications for the distribution of heavy elements in the interior, including the existence and mass of Jupiter’s core,” Bolton said. The magnitude of the observed magnetic field was 7.766 Gauss, significantly stronger than expected. But the real surprise was the dramatic spatial variation in the field, which was significantly higher than expected in some locations, and markedly lower in others. “We characterized the field to estimate the depth of the dynamo region, suggesting that it may occur in a molecular hydrogen layer above the pressure-induced transition to the metallic state.”

What I want to see is a depth map showing where Jupiter’s atmosphere ends and its solid core begins. I expect Juno will eventually be able to give us a first glimpse.

Juno has successfully completed its fifth flyby and orbit of Jupiter, dipping to within 2,200 miles of the top of the gas giant’s atmosphere.

The next flyby is set for July 11, and will zip across directly above the Great Red Spot.

Juno yesterday completed its fifth close flyby of Jupiter, dipping to within 2,700 miles of the gas giant’s clouds.

All instruments were working. There will be pictures, but the bulk of the science will be data collection, not pretty pictures.

The scientists and engineers running the Juno mission to Jupiter have decided to keep the spacecraft in its 53-day orbit for the rest of its mission rather than fire its engines to lower the orbit to its planned 14 days duration.

The original Juno flight plan envisioned the spacecraft looping around Jupiter twice in 53-day orbits, then reducing its orbital period to 14 days for the remainder of the mission. However, two helium check valves that are part of the plumbing for the spacecraft’s main engine did not operate as expected when the propulsion system was pressurized in October. Telemetry from the spacecraft indicated that it took several minutes for the valves to open, while it took only a few seconds during past main engine firings. “During a thorough review, we looked at multiple scenarios that would place Juno in a shorter-period orbit, but there was concern that another main engine burn could result in a less-than-desirable orbit,” said Rick Nybakken, Juno project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The bottom line is a burn represented a risk to completion of Juno’s science objectives.”

There are both pros and cons for using this longer orbit, detailed at the link, with.the most important being that doing nothing avoids losing the mission entirely.

Juno is set to make its fourth close fly-by of Jupiter today, dipping to within 2,670 miles of the gas giants cloud tops.

The Juno science team continues to analyze returns from previous flybys. Revelations include that Jupiter’s magnetic fields and aurora are bigger and more powerful than originally thought and that the belts and zones that give the gas giant’s cloud top its distinctive look extend deep into the planet’s interior. Peer-reviewed papers with more in-depth science results from Juno’s first three flybys are expected to be published within the next few months. Also, JunoCam, the first interplanetary outreach camera, is now being guided with the assistance from the public — people can participate by voting for what features on Jupiter should be imaged during each flyby.