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James Webb Space Telescope at the second Lagrange point (L2) from Brisbane
#1
I managed to grab a few images showing the track of the James Webb Space Telescope in its orbit around the second Lagrange point (L2). I obtained the JWST positional data from NASA's Jet Propulsion Laboratory Horizons System at:
 
https://ssd.jpl.nasa.gov/horizons/app.html#/
 
"The James Webb Space Telescope is located some 1.5 million kilometres (1 million miles) away from the Earth at what is called the second Lagrange point or L2. What is special about this orbit is that it lets the telescope stay in line with the Earth as it moves around the Sun. This allows the satellite's large sunshield to protect the telescope from the light and heat of the Sun and Earth (and Moon)."
 
I grabbed a series of images (with some cloud interruptions) on Wed 9th Feb 2022, between 9:04pm and 9:35pm AEST, (2022-02-09T11:04 to 11:35 UT), Brisbane, QLD, Australia.
 
I used a Celestron C9.25 Edge HD with the Celestron x0.7 Reducer (1645mm fl) and the QHY268M camera. Each frame was exposed for 120 secs. I understand that it is approx. magnitude 17.9.
 
After processing the image set, I saw a trail that looked too good to be true and sure enough, it was. The obvious trail belonged to an Asteroid, Number 15520, aka 1999 XK98.
 
Oh well, back to the drawing board. I loaded the individual calibrated and aligned frames into PixInsight and used the Blink Process and sure enough, I could just make out a small clump of pixels marching across the screen in the predicted positions of the JWST as the frames advanced. Each clump was barely above the background level but became obvious when blinked.
 
I loaded the frames into PS CC and used Layer Masks to combine the trail of the LWST and also raise the brightness level of the trail, above the background, to make it more conspicuous.
 
Image details (cropped from full frame):
Center (RA, hms): 07h 28m 41.669s
Center (Dec, dms): +10° 30' 09.775"
Size: 9.84 x 7.38 arcmin
Pixel scale: 0.461 arcsec/pixel
Orientation: Up is 360 degrees E of N
2022-02-09T11:04 to 11:42 UT. (9:04pm to 9:42pm AEST)
Each frame exposed for 120 seconds.
 
Asteroid details:
Object Name: 15520 1999 XK98
Object Type: Asteroid
Magnitude: 16.85
 
Bands of clouds rolled in during the session so there are a few gaps in the trail.
 
Cheers
 
Dennis

   

   
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#2
Now that's just amazing work. I was wondering if the asteroid track should be about twice the length shown in your image showing it for the length of the exposure (38 minutes). I was also wondering how faint you got as there were two other asteroids just outside the east edge of the field of view. You mentioned cropped from full frame. 2005 TO37 [mag 20.3] & 2015 XU138 [mag 21.4] Also a couple just west within the mag 20 range. And several more as faint as mag. 22.

Again, amazing and thanks for sharing.
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#3
Hi Dennis,

Again, that's some very impressive imaging! 

I watched a talk about the Tycho Tracker software, presented by its developer Daniel Parrott, put on by the iTelescope folks. Here's the link:

Tycho Tracker (tycho-tracker.com)

This software is designed to detect asteroids (& comets) & analyse light curves (variable stars & exoplanets, too), among other things. Daniel used it to image the JWST as well. You might want to check it out, especially if you're going to be imaging more asteroids in the future Big Grin .

Phil S.
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#4
Nice!
Clear skies,
Greg
Head Dude at Skyhound
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#5
(2022-02-13, 12:32 PM)bigmasterdrago Wrote: Now that's just amazing work. I was wondering if the asteroid track should be about twice the length shown in your image showing it for the length of the exposure (38 minutes). I was also wondering how faint you got as there were two other asteroids just outside the east edge of the field of view. You mentioned cropped from full frame. 2005 TO37 [mag 20.3] & 2015 XU138 [mag 21.4] Also a couple just west within the mag 20 range. And several more as faint as mag. 22.

Again, amazing and thanks for sharing.

Hi BMD

Thanks for your response, I appreciate it. Smile

The sub-set of frames used in the composite spanned 31 mins, as clouds damaged others in the session. So effectively, we are only seeing 31 mins of motion which might explain the shortened trail for 1999 XK98. I did pick up the trail of 11478 1985 CD at mag 16.7, but the others were too faint for my system.

Cheers

Dennis

(2022-02-13, 05:25 PM)PMSchu Wrote: Hi Dennis,

Again, that's some very impressive imaging! 

I watched a talk about the Tycho Tracker software, presented by its developer Daniel Parrott, put on by the iTelescope folks. Here's the link:

Tycho Tracker (tycho-tracker.com)

This software is designed to detect asteroids (& comets) & analyse light curves (variable stars & exoplanets, too), among other things. Daniel used it to image the JWST as well. You might want to check it out, especially if you're going to be imaging more asteroids in the future Big Grin .

Phil S.

Hi Phil

Thanks for your response and the link to Tycho Tracker, I appreciate it. Smile 

I'll jump over there and take a look.

Cheers

Dennis

(2022-02-14, 02:18 AM)theskyhound Wrote: Nice!

Thanks Greg, I was very surprised to have picked up the trail of the JWST. Smile

The improved sensitivity of the QHY268M has extended my range by maybe 1/2 to 1 magnitude for faint moving objects. Smile

Cheers

Dennis
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#6
Hi Dennis,

Every time I've tried to image MPs with the iTelescopes, I've failed. I set the exposure time too short trying to avoid trailing & end up recording nothing. Just need to keep at it I suppose. The Tycho Tracker software may help in that regard. It will stack images & take account of the motion of the MP in the FOV. It also can try multiple speed & position angles for a moving object, looking for the one set of parameters that produces the best image of the object. It's a very cool capability but, compute intensive. Fortunately, it incorporates GPU acceleration to speed up processing.

Phil S.
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#7
Hi Phil,

SkyTools tells you the maximum exposure time that will avoid trailing (its called the Trail Time). Most mounts can also track at the rate of the minor planet, and if you use SkyTools to generate the ACP plan, and also set the tracking on your project to "Track Target" then it will do the math needed to do that.

In most cases you can't avoid stacking the result in some way. Most stacking software can do that. What most people do is to make a movie showing the motion of the object in the field. Here's a tip for the most interesting movie: let the object trail a bit, to make a short streak. Maybe 2 or 3 times the trail time. When you make a movie, the short streak accentuates the movement in the viewers mind. For best results, track the object and let the stars trail just a little instead. I did this for 2014 JO25 some time ago.

Its refusing to post the animated gif, so here is a link to my web page about the close pass in 2017:

https://www.skyhound.com/2014%20JO25.html
Clear skies,
Greg
Head Dude at Skyhound
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#8
Hi Greg,

Yes, I know that the EC in ST4 Imaging shows the trail time. Often, I find myself using either T16 or T18 in Spain & I'm not sure how well they can track. T16 has an external guide scope, I believe. Using "Track On" will cause the stars to trail, right? How does that affect the plate solving function? 

So many of the close approaching NEOs are fainter than 18 magnitude at close approach and/or moving >2'/min. The neat thing about the Tycho Tracker software is it can make a stack for one or more moving objects as they move across the FOV. I need to watch Daniel's tutorials. One limitation seems to be trailing during the individual exposures but, tracking solves that for a known object. I suppose an initial exposure with tracking off can be plate solved, then collect the remaining exposures with tracking on.

Your video is great! Thanks.

Phil S.
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#9
Phil:

I was talking about the ability to track the target object rather than sidereal. That is controlled via the Tracking selection on the Basic tab of your imaging project. Most iTelescopes mounts support it.

If you track the target object with the mount, you need software that can handle that specifically.
Clear skies,
Greg
Head Dude at Skyhound
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#10
Hi Greg,

Yes, the 'Track On' command has the mount track the moving target. I'm not sure if T16 supports that function, since it has an external guide scope. That makes the stars trail. Can they be plate-solved, if they trail? That's why I mentioned an initial exposure without tracking to plate-sole the initial frame.

Phil S.
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