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Observe the JWST as it travels to L2
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Attached is a graph of the JWST's position in space as it is observed from an earth bound telescope. The apparent "wobble" in the trajectory is due to the observed topocentric parallax. Way cool!

The graph is provided by Dennis Conti from amateur astronomers, inc. (

Thank you Dennis!

Canon EOS Rebel XS (full spectrum mod)

Astronomik CLS CCD

Orion thin off axis guider

QHY5L-II M guide camera

Celestron CGX,Edge HD 8,0.7x focal reducer

Optec TCF-Leo focuser

Watching the video was interesting. I missed the curve the first time I watched the video.

- Scott V

Thanks Lou, that is amazing!


The link below is a YouTube video someone posted of the JWST as it was traveling away from Earth on Saturday night. It was tracked with an 8" SCT and camera taking successive 60 second exposures to record its progress as it zipped across the sky. 

It's interesting to note, although the JWST is currently traveling in a straight line (more or less), its trajectory appears curved in the video against the background of far away stars.from Earth. This is the result of the parallax created by the curvature of the Earth as we rotate -- it is unmistakably clear in the video (I would love to hear a flat earther explain their way out of this one).

The amount of observed parallax will decrease as the JWST gets farther away from us.

It would be interesting to compare similar data from other locations on the planet. Too bad we won't be able to do it from here, it looks like we're going to be cloudy until Friday.  

The good news is the Sunshield should be deployed by then which should make the JWST easier to see. However, it may be too far to by Friday observe any noticeable parallax. If I was better at math I would have calculated the parallax to expect but will leave that to someone else.

JWST Topocentric parallax

if the link doesn't work cut and paste the following:

If you want to try and track it yourself you can generate the Ephemeris table using this link, just select JWST from the drop down menu.

Clear skies!


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