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It doesn't have to be the source of the "Earth" image used to demonstrate parallax, I only want to know if a spare, prototype, or reference LORRI camera system was potentially available for this purpose. I thought I'd read that one was indeed available, but I can't remember where/when I'd read that.

Seeing this answer in Astronomy SE brought this recollection back, and the two images do look so similar (of course, they'd better look at least fairly similar) so I'd like to ask:

Question: Was a "spare LORRI" camera available to take matching image on Earth the same time New Horizons took the parallax image from the Kuiper belt?

Related:

NASA’s New Horizons Conducts the First Interstellar Parallax Experiment

Source: NASA’s New Horizons Conducts the First Interstellar Parallax Experiment

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  • $\begingroup$ Such a perfect match of two images taken with different cameras from different places is easier if both cameras use the same optic and sensor. But using a camera with better resolution on Earth and computing an image with the same resolution seems possible. So the camera on Earth should not have less resolution. Field of view should be equal or at least similar. $\endgroup$
    – Uwe
    Oct 2, 2020 at 10:25
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    $\begingroup$ From your link: "The companion images of Proxima Centauri and Wolf 359 were provided by the Las Cumbres Observatory, operating a remote telescope at Siding Spring Observatory in Australia, and astronomers John Kielkopf, University of Louisville, and Karen Collins, Harvard and Smithsonian Center for Astrophysics, operating a remote telescope at Mt. Lemmon Observatory in Arizona." So it seems no LORRI was used but observatory telescopes. $\endgroup$
    – Uwe
    Oct 2, 2020 at 11:01
  • $\begingroup$ The New Horizons image looks a little bit better, there was no light scattering caused by the atmosphere of Earth. $\endgroup$
    – Uwe
    Oct 2, 2020 at 15:31

1 Answer 1

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Pictures from Earth

The ground-based images, provided in FITS format, were selected among several provided to the mission after a call for interested amateur and professional astronomers to obtain matching images.

The Proxima Centauri image was obtained on April 22 at 12:51 UT (8:51 a.m. ET) by Edward Gomez using a remotely operated 0.4-meter telescope at the Siding Spring node of the Las Cumbres Observatory in Australia. This is nine minutes earlier than the New Horizons image, relative to Proxima Centauri time. The timing accounts for New Horizons being nearly three light hours closer to Proxima Centauri than Earth when the images were taken.

The Wolf 359 image was obtained on April 23 at 04:37 UT (12:37 a.m. ET) with the University of Louisville 0.6-meter telescope located at Mt. Lemmon Observatory, near Tucson, Arizona, operated remotely by John F. Kielkopf (University of Louisville) and Karen A. Collins (Harvard and Smithsonian Center for Astrophysics). This is 37 minutes later than the New Horizons image, relative to Wolf 359 time. The timing accounts for New Horizons being nearly four light hours farther from Wolf 359 than Earth when the images were taken.

Source: http://pluto.jhuapl.edu/Learn/Parallax/Parallax-Images.php

Wolf 359

Some background noise was left on this New Horizons image.

Several professional and amateur telescopes were used, so no spare LORRI camera could be used at different locations simultaneously.

But if the images made from Earth are of similar or better quality and resolution, all aligning may be done by digital image processing.

  • selecting image pairs with sufficient overlap
  • matching images by shifting, rotating and zooming operations
  • aligning background and stars brightness of the image pairs
  • resampling the images to get an equal resolution
  • selecting equal frames sizes

Processing

The mission team processed the images to match those taken by New Horizons.

Processing steps included:

Removing anomalously bright pixels (due to detector imperfections);
Removing subtle electronic noise;
Shifting the images to align the stars;
Removing bright pixels caused by cosmic ray strikes;
Enlarging the images;
Adding the images together to improve quality;
Adjusting alignment, brightness, contrast and sharpness 
to match the Earth-based images

#NHparallax Post your Images

Using software and methods of their choosing, amateur astronomers can combine their images with the New Horizons pictures, and post the 3D parallax products on Twitter, Instagram or other social media with the hashtag #NHparallax.

New Horizons contributing scientist, astrophysicist and legendary Queen guitarist Brian May uses an OWL viewer to check out the stereo images of Proxima Centauri he created by combining pictures from Earth-based telescopes and the New Horizons spacecraft.

So no spare LORRI camera was used for images made on Earth. I found no information if a spare LORRI camera exists.

All block quotes from Johns Hopkins University Applied Physics Laboratory website.

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  • $\begingroup$ Thank you for your thorough summary, but I think you are concluding that 1) because you couldn't find a reference to a simultaneous image from a spare LORRI camera, an image was never taken, and 2) because one wasn't taken, one could not have been taken, and 3) because a simultaneous image could not have been taken, then "no spare LORRI camera was used on Earth." I feel that A) in each case one does not necessarily follow the previous, there can be other explanations (e.g. weather), and B) I asked only if a spare LORRI camera was available and that will need a different kind of answer. $\endgroup$
    – uhoh
    Oct 3, 2020 at 1:58

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