Tuesday, August 22, 2017

Photographing the Great American Solar Eclipse of 2017

It is a rare situation when you get to gaze at an event that has not taken place in the United States for nearly 40 years. This I speak of is the Great American Solar Eclipse that took plays August 21st, 2017. Calling it the Great American Solar Eclipse may seem a big egotistical of a country to call such a celestial event as to being owned by one country. Well, it is a bit simpler then that, and is more of a matter of pride. Not that other countries have not had the same opportunity, but quite simply this event creates a few 1st times.

  • This is the 1st time since 1979 that a Total Solar Eclipse has been visible int he United States.
  • This is the 1st time since 1918 that a Total Solar Eclipse has been visible Coast to Coast in the United States.
  • This is the 1st time in recorded history that a Total Solar Eclipse has been visible in a single country only.
The next total eclipse to be visible in the United States will be in 2024.

April 8, 2024

Lasting a maximum of 4 minutes, 28 seconds, this is the next major total eclipse that will hit North America.

The path of totality first hits Mexico in Mazatlán, followed by Durango, Torreón and Piedras Negras. In the US, the path of totality will pass over:

  • San Antonio and Dallas
  • Little Rock, Arkansas
  • Indianapolis
  • Dayton, Toledo and Cleveland, Ohio
  • Erie, Pennsylvania
  • Buffalo and Rochester, New York
  • Montpelier, Vermont
  • Caribou, Maine

With that said, I had the opportunity to venture to the West coast to view this years Eclipse. I chose not to travel north to the path of totality due to fuel cost, as stations were raising them, as well as traffic. None the less I was able to capture some "stellar" shots out of Mt. Shasta, CA.

Set up and prepared
 Arriving early at the Shastice Park, I set up my gear. My tools for this celestial event included a tripod with a video/photo rig mounted on top if, with a Canon XSi atop it. Fasten to the front was a 300mm zoom lens. While my solar protection for the lens began as a auto adjusting Welder's Mask, a nearby observer having brought a few viewing filters, gave me one in exchange for later emailing her images.

Photograph to calibrate settings
photo by Errol Jud Coder

As the eclipse approached is transit, predicted to be at 9:03am PST, the park began to fill. An event tent with donated mimosas, moon pies and sun chips was erected and serving people on the other end of the park. But, I kept my location, free of the crowd. Despite that fact, I still attacked people around to look at my rig anyways. Guess its to be expected. 

To take photos of an object through a filter that completely blackens out everything around, but the sun is quite tricky. The settings have to be done just right to counter balance the extreme loss of light with the extreme brightness of the sun itself. It is because of the intensity of the sun that people were warned not to look through filters not designed for solar viewing, or through goggles/welder's masks of #14 darkness or darker. If done for too long, the light would fry camera sensors, and cause damage to people's eyes. So in having the appropriate equipment I made adjustments using the sun itself. My initial settings were f8.0 and 1/100th at 400 ISO.

At precisely the predicted time, the moon began to drift across the top right corner of the sun. Little by little it took bits out of the sun as if it was a wheel of cheese being chewed on by a hungry mouse. As the moon passed from the top right to bottom left, you could see the section on the right side that was left uncovered. It is this portion, nearly 10% that would have been covered were I in the path of totality, some 350 miles to the north. A

As the moon transitioned across the sun, I had to make minor adjustments as less light came through. As I made my changes over the hour, the sun continued it's path
Full Eclipse Progression
photo by Errol Jud Coder

Monday, July 4, 2016

Great views of Saturn System - Jun 2nd - July 2nd, 2016

Some great imaging was received by the Cassini space craft between Jun 4th and June 12th as it Orbited Saturn. Saturn, using is wide and narrow angle cameras captured great detail of Saturn's surface, rings, and Moons Titan and Rhea.

Image Credit: NASA/JPL-Caltech/Space Science Institute
On June 2nd, while turning to face it's moon Rhea, Cassini captured this image of the atmosphere of Saturn, including its northern polar region. This is using the CB2 and CL2 filters

Image Credit: NASA/JPL-Caltech/Space Science Institute
On June 3rd, angled its narrow angle camera towards its moon Rhea using its P0 and UV3 filters. It is illuminated as a full sunlit disk revealing its prominent craters. As you can see, it is much like our own moon.

Image Credit: NASA/JPL-Caltech/Space Science Institute
On June 4th, Cassini aimed it's narrow angle camera at Saturn's largest moon capturing this image with its CL1 and CB3 filters, Titan. Titan is covered with a methane case. You can see the atmosphere layer. The darker regions are surface features seen through the cloud layer.

Image Credit: NASA/JPL-Caltech/Space Science Institute
And finally, as it has swung around from its view on Titan, Cassini captured Saturn in all it's glory as it faces directly at Saturn, swooping down below its southern pole. The rights are very prominent in this image. Cassini at this time has passed the plane of its rings going from above the rings, capturing images, then passed below the rings looking out the south pole This is using its  CL1 and Infrared 1 filters

Image Credit: NASA/JPL-Caltech/Space Science Institute

As Cassini heads back north passed the plane of its rings again, it looks down at the rings on July 2nd. Top right of the screen you can see the white dot, that appears to be one of Saturns moons inside the inner ring.

Sunday, February 14, 2016

Sol 1249: Curiosity Rover Panorama at Namib Dune

Image Credit: NASA/JPL-Caltech/MSSS/composite by Errol Jud Coder
click image to enlarge
Mars Science Labatory (MSL) or more commonly referred to as "Curiosity" has continued her trek along the surface of Gale Crater on Mars, as she continues en-route for climbing Mt. Sharp.

This is a 5 image composite panorama, captured by the color imaging system of the Narrow Angle Mastcam on Curiosity from Sol 1249 on February 10th, 2016. Upon close examination it shows curiosity is on a rise with a lower field with in the crater beyond. You can see the variation in the different geological structures found on the surface, from scrapes, gullies small rocks, and in the distance, the rising edge of the crater rim itself.

Friday, September 19, 2014

67P/C-G-How to measure comet geological structures using shadows

While composing the various images of comet 67P/C-G, I noticed a number of sharply angled structures that when viewing their shadows, appeared to be much more jagged and higher then appeared. It came to me how interesting how it might be to understand the scale of many of the objects and structures of craters and mounds that we generally either see overhead or at an angle as observed from the Rosetta orbiter.

To measure distance of an object you cant directly measure, like on Earth when seen from orbit, you need a couple pieces of information. Using trigonometry, the phase angle of the sun, and the known distance in pixels of an image, this can happen. After requesting it on the Sep 11 composite post on the ESA Rosetta forums, the first inclusion of the phase angle "angle the sun is pointing at the comet" was included in the Sep 14 image post.

To show you how this works, I am using the Sep 14 composite image I stitched together from the three images captured by Rosetta.

So, what are our initial measurements?

We are told that the phase angle is 61.5 degrees
We are observing 2.5 meters per pixel. It is roughly .400m/pixel

We now need to determine the sun's azimuth. Making up North on the image. Measuring the angle of the shadow to the E/W line, it can be determined the azimuth to be 270 degrees.

How do we apply all this information to determine depth/height?

1. First measure the distance from the top of a feature, to the end of the shadow.

This feature is measured at 67.7 pixels. If you multiply it by 2.5m/pix, you arrive at a distance from top of feature to end of shadow as 169.25m.

2. Now plug in the numbers to the equation.


If we then apply the same method to the little hill to the upper right of this formation we get a height of 107m.

Now using this method, knowing the phase angle of 61.5 degrees, and measuring the pixel distance you can determine the estimated depth of craters and height of features. As long as the Rosetta forum mods include the phase angle in each of their image submissions, this can be done.

Friday, September 12, 2014

Cassini capturing storm on Saturn

NASA/JPL/Space Science Institute/Errol Coder
Captured at approximately 1,624,665 miles (2,614,645 kilometers) away from Saturn, this image composed of 3 other images using the MT2, CB2, and IR filters of the Cassini orbiter, this image seen in false color details the different cloud structures of the Atmosphere. The  cloud walls are clearly visible rotating around the central storm that resembles the one on Jupiter a great deal.

Comet 67P/C-G - Possible evidense of dust vent?

click image to enlarge
On August 17, 2014 the left image was captured. What appears to be a discoloration or shadowing in the crater stretching across a number of different boulders seems to no longer appear on the new image captured on September 10, 2014. The Sep 10 image doesn't seem to show any ridge or anything that may have caused this line of darkness. I attempted to color code a version of the above image to pinpoint which lines were in line, but it was a no go. Too many differences in stone orientation.

I wonder if this could perhaps be evidence of some sort of linear vent? The area along the line in the Aug 17 images appears rougher and more stones seems to be along the discoloration. Yet, when we see it again in the Sep 10 image, the area seems to be a lot more smoother, perhaps the smaller stones/boulders having been covered by the dust? Though, is there enough of a centripetal force for dust to settle?

Additionally, in the lower left of the right image, there does appear to be a round O shaped feature like a "Cheerio." The way the shadowing is seems to appear it has a pit veres the top or jagged edge of another boulder. Could this also be a vent? It does also seem to be there on the left as of the "Aug 17" image.

Update 1 - Sep 12
I rewatched the arrival conference video. http://wpc.50e6.edgecastcdn.net/8050E6/mmedia-http/download/public/videos/2014/08/010/1408_010_AR_EN.mp4

When they approached the comet and was testing out VIRTIS, they detected that the minimum mean temperature of the comet seems to be coming from the neck. We must then ask, why? We have seen images of direct sunlight, and it was getting direct sunlight at the time of the measurement. The max temperature came from a section on the "Body", the mid temp was on the "head", and minimum on the neck. The areas void of volatiles and are pores are the locations with the max temp. Does this mean there is either more volatiles and the area is less pores at the neck?

 The Sep 2 image did show out gassing at the neck, which would seem to make sense if there were more volatiles there.

We also saw jets at the plains area on the underside of the "body". Im interested in measurements there, and at the large plains area on the crown of the "head" as seen in my comparison. It would seem due to the smoothness that there has been activity there.

Now, since they did post the VIRTIS map on the 8th. It does show that the top of the "head" which is A site landing target is very cool, so is the area around the neck, as well as the bottom of the "body" as very cool. The large plains on the body which Bill and I had recently conducted comparisons is also the other cool location.

These three locations seem to show the evidence of activity geologically. While these areas would be great landing sites terrain wise, they are areas of cold conditions. The only one of these where a landing was considered was "A", which may have lost out due to the revelation of the temperature. The landing sites seem to be in areas other then these active locations, which for a success of the mission, would make sense, though the question stands, will there be any data regarding the outgassing if you are not in an area not as active? Come November perhaps those sides of the body will be more active. But, as they are the hot areas, it would show that not only is it porous there, but either low or no volatiles. Which goes to show, IF there are volatiles at the dark regions, what do they composed of? We wont get this answer unless we are there to drill and find out.

Possible Landing Site "A" on the crown of the "head"

Update 2 - Sep 12
After further research,

The line/discoloration is visible on the arrival images as showing during the arrival webcast. To orientate you, he image compared to the above images are upside down.The O cheerio stucture is now seen at the upper right of the image now.

Wednesday, September 10, 2014

Cassini image composite of Saturn's North Pole

Image Credit: NASA/JPL/Space Science Institute/Errol Coder
Traveling at a distance of approximately 1,699,200 miles (2,734,597 kilometers) away from Saturn, the Cassini orbiter captured a sequence of images focused at an angle above Saturn down towards it northern pole. Using its CB2/IRPO, CB3/IRPO, and MT3(Methane)/IRPO filters, I combined the three images into a false color image. The false color, while not true colors, allows the viewer to see the different divisions, features, and differences between the different characteristics of Saturn.