Monday, January 8, 2018

A very cool new tool to assist in observing our Sun (It became a testimonial)



January 5th, 2018 - It was so cold outside. How cold was it? It was so cold, my Ha solar telescope would not "tune" to the bandwidth needed to bring out the features of the Sun. You could see the Sun, but no prominences, filaments, plages, or spicule's. You may ask "how could that be"? That's because my Lunt 60mm pressure tuned Ha telescope uses air spaced etalons. When it get's too cold the air density changes enough that it prevents the scope from getting "on band".  To overcome this problem, I would need to invest in a heat controlled solar filter from DayStar. To dig deeper in the science behind all of that may be a topic for a future blog. 
So what was I doing out there anyway? I was testing a new product by Orion. It is lightweight (6 pounds) solar mount. The mount uses a combination of GPS and a video camera sensor to find the Sun and track it accurately. Click on the following link and watch it work: Orion Solar Starseeker Tracking AZ Mount
You probably are now asking; "Phil, you have been doing this a long time. Why do you need an automated device to find the Sun"? The answer is, I don't, I am pretty good a getting the Sun into the eyepiece. However, there are  three very compelling benefits:
  1. It is difficult to polar align a mount and solar scope during the day time. Not being perfectly polar aligned causes the Sun to drift out of view over a period of time (from seconds to minutes) depending on how accurate the alignment. For simply viewing, close is good enough. Making some minor adjustments while viewing is no big deal. This is true if it is just me doing the viewing. However, during public solar observing outreach events like HAL does regularly at Robinson Nature Center in Columbia Maryland, I find myself continually having to jump in to see that the scope has drifted and the Sun is no longer in the "sweet spot" or may have moved out of view altogether. This helps to explain why the folks sometimes are underwhelmed by what they are not seeing. Time to jump in and get the Sun back in center of the eyepiece. This new mount uses the built in camera sensor to keep the Sun centered with absolutely no polar alignment necessary.
  2. Continuing on with the "drifting" issue... Solar imaging is also a challenge while the Sun is drifting. If the intent is to "stack" or combine pictures to bring maximum detail, having the Sun in the same spot in the frame is a big plus (or at least close). When the Sun is drifting as multiple pictures are being captured, it becomes very difficult for the post processing tools to match pixels. When attempting to bring out very faint and fine details like prominence structure, the quality can be significantly reduced or maybe missed altogether in the final product. Once again, the built in camera sensor tracking the Sun and keeping the image centered is fantastic.
  3. In 2013 I made the decision to invest in a Lunt 60mm Ha solar telescope because I wanted very high quality and maximum portability. The telescope's relatively small format allows me to carry it, eyepieces, and various accessories in a customized backpack. The tracking mount I currently use does not travel in a very portable fashion. It includes a tripod, a German equatorial head, a counter weight shaft, counter weights, a 6 volt external battery pack, a hand controller, and cables. It is lightweight for what it is, but not practical to travel with on an airplane or pack into a vehicle for a family vacation when the trunk is packed with luggage. When I do travel out of town with the solar scope, I travel with a simple tripod and mounting head. No tracking and no imaging (other than a quick snap shot maybe). It is simple and portable. But not the same experience as when using a tracking mount. 

The Orion Starseeker setup is so compact and efficient, I am able to pack the entire system along with the Solar Scope and accessories in the backpack. The light weight tripod straps to the outside of the backpack.

This is possible because the mount is completely self contained. There are no counter weights, no cables, and no exterior battery pack. The system runs on eight AA batteries which are contained right in the mounting head. It's amazing. The entire backpack weighs just 25 pounds and I have an entire Solar viewing system enclosed. I even have the ability to pack the camera inside the backpack and the lightweight laptop computer in the front pouch which will allow me to have a full solar imaging system in the backpack and ready to travel. This will bring the weight to approximately 30 pounds. Still not too bad.

Yes, I not only tested the Orion Mount in the parking lot of Company Seven Astro Optics on a blustery 14 degree day with wind chill into the single digits, I purchased it. The system sells for around $350, which is also a very good value for the benefits it provides.

Time will tell how it hold us under regular usage. It is specified to hold a telescope and accessories up to 7 pounds. My solar telescope with an eyepiece and in the "double-stack" configuration weighs in at 10 pounds". I am hoping that they spec'd the system conservatively and the gears will hold up. Check back at this time next year and let's see how it is doing. Also, the setup is so lightweight that it is easy to bump or move it out of place while adjusting the scopes pressure tuner. (The tuner was also a little stiffer than normal because it was freezing cold outside). It was just as easy to move it back into place without a problem. If I want greater stability I can take the head assembly off of the very lightweight aluminum tripod that it comes with and put it right on to my much more substantive carbon fiber tripod. Portability will not be sacrificed. It will just add a little more weight.

I am very excited to run this new setup through its paces. I am also looking forward for the temperature to return to a point where the telescope will "tune" properly and I don't have to be wearing a full winter get-up to look at and image the hottest object in our solar system.

Clear Skies!

Phil






Sunday, December 31, 2017

Solar Mystery Solved


Note: The pictures shown below were imaged at a different orientation. This accounts for the features to appear at different locations on the Solar disc.



On September 9th, 2017 I captured several images of the Sun which showed a very interesting feature. Above, on the top image if you look down just inside the 5:00 position you will see a circular feature. The image just below shows a closer look. Inside that apparent circle was a very active area including two active regions (AR 2674 and AR 2679). Sunspots and plages are clearly visible. Plage is a French word meaning "beaches". It always appears around a sunspot or an "active region" as a bright dense area in the chromosphere. You can also see the effects of the magnetic fields on the chromosphere in that area.

There were many opinions as to what this circular feature could have been. With the help of HAL member and retired NASA engineer Bub Dutilly, I was connected with Dr. Joe Gurman at NASA Goddard Space Flight Center.  Joe did a considerable amount of research reviewing many images of the Sun as well as data that was gathered from the Solar happenings on September 29th. Using data and images from Big Bear Solar Observatory in San Bernadino County, California. Dr. Gurman was looking for like information to compare against. He also used data recorded at SDO (Solar Dynamics Observatory at NASA Goddard).  One of the theories is that this could have been a "Moerton Wave" (A wave-like disturbance in the chromosphere initiated by a solar flare). The following video recorded at SDO was viewed to see if it indeed was a "Moerton Wave". (The area we are observing is just inside the edge at the 3:00 position). https://umbra.nascom.nasa.gov/aia/aia_20170909_193_diff.mov  As a result of that research we were able to eliminate a "Moerton Wave" as a possibility. Dr. Gurman concluded; "I believe it is a filament channel in the form of (more or less) a circle. They happnen."

For additional opinions Dr. Gurman referred me to two other NASA researchers at Goddard, Dr. Holly Gilbert and Dr. Therese Kucera.

Dr. Gilbert observed that the circle is not really a circle. She said; "It might be "two filaments (one very curved on the right, and the other on the left slightly curved). Although they looked connected, I don't think they are".

Dr. Kucera compared my images to those on the NSO GONG site (National Solar Observatory - Global Oscillation Network Group). Dr. Kucera said; I think what we are looking at is a curved shape in the fibrils, thin dark threads on the chromosphere that can trace the magnetic field direction." Immediately below is the image from the NSO GONG site. The area we are talking about is shown just inside the edge at the 3:00 position.


In closer review of the "circular feature" it is apparent that it is not a circle at all. It is the conclusion of the experts that I imaged filaments (probably 2) in such a way that they formed almost a circle. In all of the September 29, 2017 Hydrogen-alpha solar images I have been able to find, it appears that I have the only pictures that show such a clearly defined filament structure.

(Filaments are masses of relatively cool and dense material suspended above the photosphere in the low corona by magnetic fields, generally along a magnetic inversion, or neutral, line separating regions of opposite magnetic polarity in the underlying photosphere. They appear as dark, elongated features.)

Thanks very much for all of the time and expertise that Dr.'s Gurman, Gilbert, and Kucera of NASA Goddard dedicated to this research.

Clear Skies!

Phil

Note: Definitions source: The Cambridge Encyclopedia of the Sun

Sunday, October 29, 2017

It's been 4.6 billion years in the making. And we have about 5 billion more years to enjoy it!

Our Sun was born about 4.6 billion years ago, give or take a day. With just about 5 billion years (give or take a day) until our Sun burns up it's fuel, expands, and engulfs the Earth, we have that much quality time to observe it, study it, and be amazed by it.

I have been honored by the Howard Astronomy League (HAL) by being asked to serve as the club's Solar Observing Chairperson. As part of this role, I will be posting a least one blog a month with what I hope will be interesting information relative to Solar observing, imaging, and information. I will also be encouraging those of you who are interested in learning more about our Sun and who already enjoy observing it to participate in get together's and and related solar events. I also encourage you to post your interesting Solar observations on this blog.






When observing the Sun, safety is always the first step. Ensure that you are always and only using telescopes, binoculars, and glasses that are properly filtered to protect you from damaging your eyes or even causing blindness. In a future blog, I will write about Solar safety.

With the light from the Sun arriving here on Earth in just under 8 and half minutes, combined with its ever changing features, every observing event becomes a unique experience. You can go from one day seeing just a big ball in the sky to another day of tremendous activities featuring sunspots, prominence's, filaments, spicule's, plage's, planetary transits, solar flares, and even unexplained happenings. See my next blog on an imaged Solar mystery.

Solar observing can be done anywhere you have a clear view of the sky . I have observed in my backyard, in parking lots, in different States, on the beach, at public events (for all to share), and in the mountains. Technology has reached the point where regardless of the size of your budget, you can safely observe, image, and enjoy the Sun. Because it is best to observe our Sun during the daytime, you don't have to stay up late at night or maybe all night to do your astronomy.

Observing the Sun is fun for all ages.

Until next time....

Clear Skies!

Phil Whitebloom
Howard Astronomy League
Solar Observing Chairperson