Tuesday, November 29, 2022

US Postal James Webb Space Telescope Stamps


Today I received 20 stamps from the US Postal service. With the release of this vibrant stamp, the U.S. Postal Service celebrates NASA’s James Webb Space Telescope as it continues its epic mission to reveal the cosmos as never seen before.

“When anyone who uses these stamps looks at this telescope, I want them to see what I see — its incredible potential to reveal new and unexpected discoveries that help us understand the origins of the universe, and our place in it,” Robert D. Cabana, NASA associate administrator and former astronaut said. “This telescope is the largest international space science program in U.S. history, and I can’t wait to see the scientific breakthroughs it will enable in astronomy.”


Stamp Artwork

The image on the stamp is an artist’s digitally created depiction of the telescope against a dazzling starscape. Its 18 gold-coated mirror segments — hexagons that combine to form its 21-foot-wide primary mirror—can pick up faint heat waves representing the universe’s first accessible starlight from billions of light-years away. Opposite, supported by three struts, is the secondary mirror. Below are the telescope’s solar shield, computers, control machinery, and the solar array that provides power.

The words “Webb Space Telescope” appear in white along the bottom edge of the stamp. “USA/FOREVER” runs vertically up the left-hand edge. In the selvage, at top, “James Webb Space Telescope” is printed in gold against the darkness of space, with an image of a star in a gap between the title’s last two words. Additional stars and galaxies appear in the background. This image was taken to confirm the perfect alignment of the telescope’s mirrors.

Art director Derry Noyes was the designer for the stamp project using existing art by James Vaughan and an image provided by NASA and the Space Telescope Science Institute.

Sunday, November 27, 2022

Mars with UV-IR blocker and bandpass filter IR742

 


Imaging Mars on Friday, November 25, 2022. My first time use of an UV-IR blocker together with my ASI224MC color camera. The white polar cap is now good visible, which was not the case during my previous imaging sessions. This could confirm that I was imaging in IR and polluting it with visual light. 

Next to this, I used also my new bandpass filter IR742 for the first time. The result is an mono picture with some great details. 


Setting: TAL200K f/8.5, ASI224MC, Barlow x2, ADC
Filters: IR/UV blocker and IR742nm
Software: SharpCap 4, AS3!, CS4, DeNoise AI

Saturday, November 26, 2022

BlueWalker 3 - Estimate Magnitude 1

Observing satellite BlueWalker together with SeaSat1. Estimating magnitute around 1. 

Satelliet BlueWalker 3 is a prototype satellite for AST & Science's SpaceMobile mobile communications constellation. The satellite will be to test AST & Science's patented technologies for connecting to cellphones in a space environment for their planned SpaceMobile constellation. The 1.5 ton satellite will deploy a 10 m diameter phased array antenna with 64 m2 area consisting of numerous identical sub-antenna modules to connect directly to standard mobile phones.
It is a prototype for the larger operational BlueBird satellites. The first five BlueBird satellites will be similar to BlueWalker 3, while the remaining will be larger.

Sunday, November 20, 2022

Mars and Infrared

 


My picture of Mars, earlier this week, is made using my ASI224MC camera. The ASI224MC, is a color camera with some good respons in the near infrared. As I did not use an IR/UV blocker  the picture is an IR picture polluted with visual light -see also article "why you should use an IR cut filter with a  color camera". The color of my Mars picture is reddish/pink which is not a realistic color. I saw different pictures of Mars from other amateurs which are using an IR/UV blocking filter. Threrofor I ordered an IR/UV blocker  with the following properties.


On top of this I will purchase two IR bandpass filters: 642 and 742nm IR bandpass filters. Below is a graph showing the IR bandpass and the sensitivity of the ASI224MC camera.



RGB lines represent the sensitivity of ASI224MC
642, 742 and 807 are graphs of the IR bandpass filter.
The vertical lines are emission lines as a reference eg. H-alpha, OIII, Na, Hg
The grey line in the back is a typical curve of an astrosensor.


Tuesday, November 15, 2022

Mars Reworked - R,G,B split with PIPP and WinJupos



It had been a while since I photographed Mars. On Sunday, November 13, the conditions were favorable with a completely open sky. As a setting I had my TAL200K with ASI224MC camera. Furthermore an ADC and barlow x2. The polar alignment went flawlessly with an “excellent” result and only 8 arcseconds deviation! In total I have been outside for 3 hours and I have made 8 shots of 3000 frames (145fps). The recordings were made via SharpCap 4 and saved in SER format. 
On Monday morning I have the SER files with AS3! stacked and edited in CS4. Personally, I didn't think it was bad and could compare the details with the Mars Mapper. However, I received feedback from Johan R and Walter about: where the polar cap was and why the picture looked so red. In the meantime I had also sent my photo through the VVS maillisting where I received the same feedback from Geert VDB and Luc DS. So back to the drawing board. Most planetary photographers shoot with mono cameras and RGB filters. Few do it with a color camera and that's where the problem is. The colors of a color camera do not always correspond with reality, so with the ASI224MC. The white balance must be adjusted to R52(R58) and B99(B99). Since the recordings had already been made, I got the tip from Walter to split the SER files into R, G, and B images. This was done with PIPP software. Then stacking with AS3! (25% retention of the frames). Using WinJupos I then merged the obtained R,G,B photos where the gamma of Blue is 2x higher than R and G. This way I get an RGBB image. This image was edited in CS4 and in DeNoise AI. 

The result is a beautifully detailed Mars image with a more realistic color and a visible polar cap. A satisfied amateur astronomer 😊

Monday, November 14, 2022

Mars - November 13, 2022 - Compared with Mars Mapper



Picture of Mars from November 13, 2022, UT22h58 with fair to good seeing conditions.

Setting: TAL200K f/8.5, ASI224MC with ADC and Barlowx2
Software: SharpCap 4, AS3!, CS4, DeNoise AI

Picture is compared with Mars view from Mars Mapper - see this link. Details are matching well.

Mars - My first picture 2022


My first close-up picture from Mars this year. The red planet is currently 0,57 AE away from Earth and is 97% illuminated. The angular diameter is about 16,4".

Setting: TAL200K f/8.5 with ASI224MC and ADC, Barlow x2
Software : SharpCap 4, AS3! (25% stacked), CS4 and DeNoise AI


Sunday, November 13, 2022

Calculating Limb Darkening Coefficient

I calculated the Limb Darkening Coefficient from the Linear Limb Darkening law assuming a plane-parallel solar atmosphere.:





As a base, I used a picture from the solar disk taken during the recent solar eclipse with an OIII filter (500nm). Using ImageJ software I was able to plot the intensity (limb darkening) graph by retrieving the gray intensity data per pixel. Using above formule, I calculated the Linear Limb Darkening coefficient (LDC). To calculate the LDC, I took the average LDC's of the radius between 0,9 and 0,3 . This results in a LDC of 0,22 (500nm)

I put this data together in a graph which combines the intensity graph from ImageJ and the theoretical derived graph with a LDC of 0,22.


Discussion:
In the literature I found LDC's  of around 0,8 (eg. Dias-Cordoves see this link)  


Conclusion : my LDC calculation is not really near the ones published in different studies. 

See also interesting LD calculators like the one for the James Webb Telescope. See this link





Saturday, November 12, 2022

Dynamic of Sunspot group AR3141 and AR3145

Picture of sunspot group AS3141 and AR3145 on November 11 and 12.

 


Sunspot AR3141 - CaK and White light

 




Sunspot AR3141, AR3140 and AR3145 observed on November 12, 2022. Sunspot AR3141 not only photographed in White Light but also with CaK filter.

Setting : TAL200K f/8.5, ND3.8 filter, CaK filter, ASI290mm, Barlow x2
Software : SharpCap4, AS3! (50% stacked), IMPPG, CS4


Friday, November 11, 2022

Sunspot AR3141 - Light Bridges



Some high clouds but still I was able to make some pictures of Sunspot AR3141 (and AR3140, AR3145). Sunpot AR3141 is a complex sunspot with an beta, gamma, delta configuration. 
The sunspot has also a couple of bright light bridges.

Setting: TAL200K f/8.5 with ASI290MM and ND3.8
Software: SharpCap 4.0, AS3! (25% stacked), IMPPG, DeNoise AI and CS4



Saturday, November 5, 2022

Moon and Jupiter

Jupiter north of the Moon with Golden Handle.



Halo 22° and Circumzenithal Arc


Around midday, the sun was surrounded by a halo 22° and a faint circumzenithal arc.

Friday, November 4, 2022

Partial Solar eclipse Oct 25, 2022 - calculating max coverage using ImageJ

The partial solar eclipse of October 25, 2022 was tracked from Averbode. With some clouds, the conditions were less good than last year on June 10, 2021, but still sufficient.The solar eclipse was tracked with a TLAPO80/480 f/6 and Nikon D7500. A solar filter ND3.8 and OIII filter were used. A total of 127 photos were taken represesnting 3.56Gb of data. Several photos were edited and one timelapse of the process was created. You can visit my blog for this see this link .

I tried to determine the maximum of the solar eclipse as well as the time of the maximum. ImageJ software was used. To determine the surface of the sun, raw photos were uploaded and after selection via color contrast, the number of pixels that  which are not obscured are calculated. The “solidity” was also calculated. This is the result of dividing the area of ​​the eclipse by the convex area (smallest perimeter of a surface). To calibrate the time with my Nion D7500 photos, I used the time via the Frankfurt atomic clock.

I have shown in the top right corner the data for Averbode as obtained from www.timeanddate.com


Conclusion: the solidity gives much lower coverage values ​​than the pixel values. The traject of the eclipse and the calculations are influenced by the clouds on the photos. The time of the maximum is 2 minutes earlier than indicated on the website. The coverage value is 2% points higher than indicated on the website. 
A fun exercise that mainly shows the power of the ImageJ program.

Thursday, November 3, 2022

ICE Software: Combining H-alpha images of the Sun

I had some difficulties to merge images using photoshop (CS4). When reading the magazine Heelal (jaargang 67, nr11, november '22 p22) I saw an article on making mozaiks using ICE (Microsoft Image Composite Editor). According to Microsoft, the software is retired and not supported any more. I took my chance and downloaded and installed the 64bit version.  

I took my solar H-alpha images from May 22 and drag them into the ICE software. The result was mindblowing. The difference with my photoshop merge is huge as you will notice yourself. 

To download the software - see this link.