Saturday, December 31, 2011

A final post for 2011

The year 2011 has been a busy one for me, and I am resolving to make 2012 a more productive year in terms of image processing.   In the meantime, here is an improved version of the last Voyager 2 image of Ariel prior to near encounter in January 1986.

Processed image Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Wednesday, December 07, 2011

A Crescent Callisto

This is a crescent view of Jupiter's moon Callisto taken by Voyager 1 on March 6, 1979.   Many of the pictures that were taken in this dataset smeared or missed Callisto, and all of the images are underexposed.  The smoothness of the day/night terminator is a reminder that for all its craters, Callisto is a very flat world.

Processed image Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Monday, November 28, 2011

A new version of an earlier Triton mosaic.

A few years ago, I posted this massive installment of Triton images. This is the large, high resolution mosaic seen through a high pass filter to cut down on the effects of illumination differences - such filtering helps to focus on smaller features across the image.

Processed image Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Monday, November 21, 2011

A (nearly) full Callisto from Voyager 2

This is one of the best full-phased images of Callisto available.  It was taken by Voyager 2 during its 1979 flyby of Jupiter just before Callisto fully filled the field of view of its narrow angle camera.  

Processed Image Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Thursday, November 10, 2011

In Honor of Phobos-Grunt, a View of Halley's Comet from Vega 1

The Russian Space Agency attempted to return to planetary exploration this month with November 8th's launch of Phobos-Grunt.   It would be only the second planetary mission launched by Russia since the demise of the Soviet Union (the first was the ill-fated Mars '96).   It is currently stuck in earth orbit, and whether or not it can be salvaged will be known in the coming day or two at the latest.

This image is a stack of three images taken of the nucleus of Halley's Comet by the Soviet Vega-1 spacecraft as it flew by on March 6, 1986.  The images were badly blurred by optical problems in the camera, so a lot of deconvolution had to be applied.   Bright gets can be seen emanating out of the long, skinny nucleus. 
 Processed Image Copyright Ted Stryk, Raw Data Courtesy the Russian Academy of Sciences.

Update:   Phobos-Grunt Status - this does not look good.
Experts assure that "Phobos-Grunt" will not crash on Moscow 
MOSCOW, November 11. In the case of a uncontrolled re-entry, Phobos-Grunt’s inclination allows it to crash into half of Eurasia, but in Moscow is not in the area in which it could crash crash. This is according to  RAI Navosti magazine News of Cosmonautics editor and columnist Igor Lisov.

"Barring a miracle, and experts fail to establish communications with the mission, it will remain out of control. If it is out of control, then there is the option to shoot down with a missile. We know that China and the U.S. have facilities, which can bring down the spacecraft" - said Lisov.

Recall that the launch of the Phobos-Grunt" took place on 9 November 2011. After separation from the booster, the spacecraft went into a parking orbit around the Earth. It then experience a problem, because of what tits propulsion system did not operate and so it did not end up in a transfer orbit to Mars, but remained in near space.

Now ground control is trying to establish communications with the spacecraft; however, it did not respond to commands from Earth. According to specialists, if the spacecraft cannot be saved, then it may fall to Earth on November 26.

Friday, September 16, 2011

A Distant View of Triton

My interest in planetary exploration was born in the 1988-1989 school year.  As a bored fourth-grader, I was paging through my science book when I came across this image .  I refuse to soil my blog with it.  My thought was that there was no way something in nature could be that ugly.   I began to go to local libraries, looking up anything I could find on the planets, trying to figure out what they looked like.  Saturn, it turns out, was a beautiful world, nothing like the picture.  I even talked my parents into getting me a telescope for my birthday.   I spent two hours looking before I finally found Saturn.  It was a beautiful yellow world, encircled by rings, as I had seen in some of the better books I had found.

I began to search libraries for more planetary images, joined the local astronomy club, and began connecting to BBS boards online to see more images and to find out what was going on in planetary exploration.   What I found was quite exciting.   Voyager 2 was approaching Neptune, Magellan was getting ready to head to Venus, Phobos-2 was about to swing into orbit around Mars, and Galileo was about to head to Jupiter.

Phobos-2 would send back some incredible images but then fail.   Next up was Voyager at Neptune.  I would ride my bike at least once a week to all the local libraries to see if a new image was released in a magazine or newspaper.  I would search BBS boards for any new information.   As I read predictions for the Neptune encounter, its large, quirky moon Triton captivated me.   Was it active?  Would we see through its atmosphere? 

As the encounter approached, I would buy a newspaper every day in case there was an update.   A few days before the August 25 encounter, there was an image of Triton published.  It was taken on August 21, and was blocky and fuzzy.   Still, it was the first image of I had ever seen that showed actual surface features on Triton.

I clipped that image and probably still have it somewhere, although I'm not sure where.   I haven't seen it published anywhere else.  I decided to dig up the data set and produce a view of Triton as seen by Voyager that day.   It was this encounter, along with the images from the Phobos-2 images, that crystalized my interest in both planetary science and in image processing, transforming it from a passing fancy of childhood to a lifelong passion.

Processed Image Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Thursday, September 08, 2011

Io from Voyager 2

I have never worked much with Voyager 2 Io images.  Voyager 1 flew much closer to Io, and Galileo of course imaged it from even closer and monitored its volcanoes over a period of years.  The Voyager 2 images are relatively distant.  Still, some of them are quite sharp and show Io from angles not seen by other spacecraft.  This image is made from some of the closest Voyager 2 images, taken on July 9, 1979 from about 1.1 million kilometers.   One can see a multitude of high mountains casting shadows near the terminator.   One can also faintly see the night side of Io illuminated by reflected light from Jupiter.

 This is an alternative version.  It improves the view of the day side at the expense of suppressing the night side.
 In this image, I worked to compensate for the fact that the filter coverage is different on different parts of the disk and several color filters are badly underexposed by the terminator.  I think it is the best looking version.

Here is an enhancement of the night side.  Because it is very faint, this image appears very noisy.

Processed Images Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Friday, August 26, 2011

Some projects don't work out...

When I do work with limited and/or poor quality datasets, the failure rate is high.   Such was a recent attempt to make a perspective view from images of the surface of Venus taken in 1975 by Venera-9, the first spacecraft to take pictures from another planet.   Below is my enhanced version of the panorama it took.
Given that the spacecraft was only expected to last around an hour on the surface and its  slow transmission rate (by modern earthly standards), the view was only 128 pixels high and about 512 pixels wide.  In order to sample both the horizon and nearby areas with good enough resolution to distinguish what was being seen, the camera scanned a 180 degree panorama that started out looking at the horizon, dipped down in the center to the foot of the lander, and then went back up to the horizon on the other side.   My goal, following work that Don Mitchell has done with the much better datasets from Veneras 13 and 14, was to make a picture that would show Venera 9's surroundings from a more normal perspective.  I had reprojected the corner images before, as seen below.
These views, while from a somewhat more human perspective, are still awkward to look at.  My goal was to sample features at different distances in order to create something resembling an ordinary photograph.  The problem was that unlike Veneras 13 and 14, which took similar scans on both sides of the lander, Venera 9 only took one, and at significantly lower resolution.  In fact, the compilation is so obvious that some blurring was necessary to disguise the fact that the scan lines and pixels were going in different directions in different places.   Also, while I intended the image to be 480x640 pixels, the largest presentation it could sustain and still look half way presentable was 275x360.  Still, at about 99,000 pixels, it is still oversampled (the original data comes to about 65,500 pixels).  In other words, the best that could be managed was an image slightly less than 0.1 megapixels.   It also took some inventiveness.  One side of the panorama shows a ridge in the distance,  the other side does not.  The transition had to be guessed at.  Also, filtering was done to reduce the effects of differing illumination angles, improving the believability factor but at the expense of yet more resolution.

This is the finished product.  It turns out that there was not enough data in the Venera-9 set to make this work.
Finally, for fun I made a colorized version based on the Venera 13 and 14 color images.
Data courtesy the Russian Academy of Sciences.   Processed images Copyright Ted Stryk.

Tuesday, August 23, 2011

A close shot from Pioneer 10

This rarely seen image, badly damaged by the effects of radiation on Pioneer 10's imager, is from dataset A4.  It was taken 726,000 km from Jupiter.  A hint of the red spot can be seen on the terminator.   This image is still a work in progress.

 Here is an alternate processing with some cosmetic improvements and scaled closer to the original pixel size.

Processed image Copyright Ted Stryk.   Original prints scanned to create this image courtesy NASA/Ames.

Sunday, August 21, 2011

Jupiter from Pioneer 11.

This exquisite image of Jupiter is from Pioneer 11, the last (and the closest - 760,000 km) image to show the planet's full disk before closest approach. The image, C5 in the pioneer catalog, is a combination of a red and a blue light scan with a synthesized green.  Images like this present a processing dilemma.   Pioneer got an unusually good view during approach of the south polar region during approach and an even better view of the north polar region as it left.  In my attempts to process these images, there appears to be a blue glow around the polar regions, perhaps due to a haze.  However, since I am working from scans and not digital data and the scanned prints are of varying quality (the yellowing of the individual sheets of paper was surprisingly inconsistent) and this is near the limit of what can be discerned.  Thus, figuring out if it is real is difficult.  The limitations of the medium, plus the 6-bit nature of Pioneer images, makes interpreting faint features very difficult.
While this dataset is very limited, it provides some of the best views we have of Jupiter's poles, so I intend to do more work with it in the near future.

While I'm at it, here is image C25, taken from 2.3 million kilometers.   It shows a higher phase angle than can be seen from earth.  It does not one of the polar region images, but it is a pretty picture nonetheless.

Processed image Copyright Ted Stryk.   Original prints scanned to create this image courtesy NASA/Ames.

Thursday, June 23, 2011

NASA's DAWN spacecraft is approaching Vesta, the second most massive object in the asteroid belt.  It is now about 200,000 km out, and the view is getting very interesting.  Here is a stack of several frames taken on June 20, 2011, and released as part of an approach movie on June 23, 2011.

Data Courtesy approach sequence/movie released by NASA/JPL-Caltech/UCLA/MPS/DLR/PSI.    Much thanks to Emily Lakdawalla of the Planetary Society for breaking up the individual images in the movie.  Processed Image Copyright Ted Stryk

Wednesday, May 25, 2011

Goodbye, Spirit

Spirit, the first of the two Mars Exploration Rovers (MERs) to land on Mars, was officially declared dead this week.  It had been silent for about a year, but there were hopes that improving seasonal conditions might lead to its reawakening.  Sadly, that did not happen.  As a small tribute, here is a small panorama, taken in early 2004, looking at Grissom Hill.   Spirit traveled in the opposite direction, so it got its best views early on.  In order to combine images taken from slightly different positions, I had to cut out the foreground, as it would not match up.   Until we meet again!

Additionally, here is a reworked version of Spirit's view of its own heat shield from the 82nd sol (Martian day) of the mission).

Until we meet again, Spirit!

Processed Images Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Thursday, April 07, 2011

A View of the Martian Sufrace From Viking 1

This view is a super-resolution view of some the area behind Viking lander 1.  It uses images taken between 1976 and 1978.   A large pile of rocks can be seen, as well as a small crater on the horizon.  I did this work in 2004.  One of my goals is to rework some of these images again.   At the time, I stacked the images in an 8-bit format.  By using a 16-bit format, I can minimize data loss as the image goes from through various stages of processing (given the size of the images and the limited memory/speed of the computer I was using at the time, working with 16-bit data was prohibitive). 
The second image is a vertically stretched version of the above image.  The stretching makes recognition of the crater rim easier.

Processed Images Copyright Ted Stryk, Raw Data Courtesy NASA/JPL

Thursday, March 24, 2011

A Storm on Saturn

For the past few months, a storm has been raging on Saturn.  Over time, the storm has been stretched into the white band seen in the mid northern (upper) latitudes.   This view, taken on March 12, 2011, shows the late stages of the storm.  It was taken using the Advanced Camera for Surveys (ACS) wide field camera on the Hubble Space Telescope, with color data taken from earlier images of a previous storm by Wide Field Planetary Camera 2 (WFPC2), a camera since replaced by the Wide Field Camera 3 (WFC3).

Raw Data Courtesy NASA STScI,  Processed image Copyright Ted Stryk

Sunday, March 20, 2011

Reality and the "Supermoon"

I don't usually post images from my own telescope on this blog, but I will break with tradition tonight.   You have likely heard all the fuss about the "Supermoon."   The reality is is that it is a whopping fifteen kilometers closer to earth than its closest approach last year (four one-thousandth of one percent!).  That's it.  Other than a bit of trivia that provides a great excuse to go out and look at the oft-neglected moon, there is nothing more to it.  The end.

Below is a view of the moon on the evening of March 19, 2011 ("Supermoon" night), with a 10-inch telescope through a thin layer of clouds.  

Image Copyright Ted Stryk

Monday, March 07, 2011

Wanted: In Digital Format...and my 2011 LPSC poster presentation...

I am posting this in hopes that someone will see it and know where I might find the dataset I am looking for.   The image of Titan seen here is image G14.   It is the best of a sequence that included G15 and G16 (for each number, there are two images, a red channel image and a blue channel image).  If any of you have or know where I could find these (or any other Pioneer images) images in their native digital format (probably in the form of a printed out matrix), please let me know.
 While I'm at it, here is how the image looks with both channels separated and without any processing.  Again, what I am looking for is the digital data, not a better source to scan.
While I'm on the subject of Pioneer 10 and 11, here is the abstract I submitted for the Lunar and Planetary Science Conference (which I will be attending this week).  It was written before my visit to Ames Research Center in January.  I did find some better material to scan and some fragments, but I did not find the digital data I had hoped to.  The most useful projects will likely be a high resolution mosaic using the closeup data from Pioneer 11 as it passed over Jupiter's North Pole and a sequence (perhaps to be made into a movie) of Jupiter rotating from above the North Pole as Pioneer 11 receded. Here is the poster I am presenting, which is a combination of older work and very preliminary processing.  

Each image is designated by a letter.  Here is a guide to the images based on those letters:

A.  Pioneer  11 image C5 (Jupiter) Scans
B.   Pioneer  11 image C7 (Jupiter) Scans
C.   Pioneer  11 images C1 and C2 (Jupiter) Scans
D.  Pioneer  11 images D1 and C2 (Jupiter) Scans
E.   Pioneer  11 image D16 (Jupiter) Scans
F.    Pioneer  11 image D19 (Jupiter) Scans
G.  Pioneer  11 image D7  (Io)  Digital.
H.  Pioneer  10 image A24 (Ganymede) Digital
I.      Pioneer  11 image D3 (Jupiter) Scans
J.     Pioneer  11 image F7 (Mimas transiting Saturn) Scans
K.   Pioneer  11 image F12 (Saturnian Rings) Digital
L.    Pioneer 10 image B38 (Jupiter with “Little Red Spot”) Scans
M.     Pioneer 10 image B39 (Jupiter with “Little Red Spot”) Scans
N. Pioneer 11 mosaic using data from images F33, F19, and F12-F5 (Saturn) Mix of digital data and scans.
O. Pioneer 10 image A2 (Jupiter – Great Red Spot) Scan

This is only the tip of the iceberg...

Scanned material and raw data courtesy NASA/Ames Research Center.  Processed images Copyright Ted Stryk.