NEW DISCOVERY: PATCHICK-STROTTNER-DRECHSLER 10- Discoverers: Dana Patchick, Xavier Strottner, Marcel Drechsler
- Catalog designation: PaStDr 10 / PNG 259.6-32.0
- Constellation: Pictor
- Diameter: 55 arc min
- Coordinates (J2000): 05:38:36.82 -52:16:54.50
- Image processing: Aygen Erkaslan
- Data acquisition, data compilation, data preparation: APO Team & Aygen Erkaslan
We are delighted to publish the first color image of
PaStDr 10 - a planetary nebula candidate officially accepted and registered by Pascal le Dû and Professor Quentin Parker.
How did we embark upon this journey ?
The endeavor of shooting PaStDr 10 started following a few emails exchanges between Marcel and Aygen. Marcel kindly suggested to work on this peculiar candidate, and given the challenge of the project - to publish the first color image of this beautiful nebula - the team started to collect the data without further due.
What type of object is it ?PaStDr 10 / PNG 259.6-32.0 was discovered by the US-French-German team of Dana Patchick, Xavier Strottner and Marcel Drechsler in 2020 by scanning Digital Sky Surveys. The H-alpha shell appears in several surveys, but is most clearly visible on the SHASSA H-alpha plates. The shell is also well visible on the red plate of the UKST survey.
PaStDr 10 is thought to be a planetary nebula with an estimated size of 55 arc minutes and is located in the constellation Pictor, not too far away from the famous star Beta Pictoris, a young planetary system 63 light-years away from earth. Further, we noticed that Canopus - the second brightest star in the sky - is only some 7 degrees to the east, approximately the same declination.
The white dwarf mysterySince PaStDr 10 is a very large possible planetary nebula, there should be a visible white dwarf in such an extended object. At first glance, however, there did not appear to be a conspicuously blue star that might be a white dwarf. So the team checked the data of the ultraviolet satellite GALEX and two very hot objects immediately became visible. Firstly, the very bright, yellow and large star HD 37864 (Spectroscopic Binary), whose companion is probably a white dwarf. However, HD 37864 is not located in the center of the structure, but far to the north.
The second star was located much more favorably inside of PaStDr 10 and also showed a strong UV signal, so that the probability was high that this could also be a white dwarf. But again, the star was not blue, but had an inconspicuous whitish-yellow color according to the DSS Survey. Only the relatively new Dark Energy Survey (DESI) with its extremely high-resolution data revealed the dwarf we were looking for. The extremely blue dwarf is partially obscured by a yellow main sequence star. It is not known whether this is just an optical occultation or whether the white dwarf is in a binary system with the yellow main sequence star.
A few words about the second hot star that is more favorably inside of PaStDr 10. DR3 parallax data exists on the blue dwarf and yellow main sequence star that is approximately 1.7" distance. The blue dwarf is of Mg. 18.93 and has a plx. of + 2.9001, while the yellow star is of Mg. 17.57 with a plx. of + 0.9560. This means the dwarf is on average some 345 parsecs distance, while the yellow star is on average some 921 parsecs distance. Therefore, we can assume with a good degree of certainty that the two are unrelated. 
When stars like our Sun die, they gently sheds their outer layers, and as a result of this chaotic process, beautiful colors start emanating from the dying stars - provided you can spot them with adequate instruments. Solar-type stars do not become SNR or black hole, but become white dwarfs. According to the Center of Planetary Nebula (Harward), gravity and other influences shape the cloud into interesting patterns, and the complex chemicals inside the nebula glow in interesting colors when lit by the white dwarf. Does that mean that we can assert with confidence that our discovery is the result of similar activities - we can't say for sure.
Aygen's notes on the processing Before going any further, I feel extremely privileged to have processed this new discovery. My sincere gratitude towards the whole team for this honor.
From a processing point of view, this is by far the most challenging object that I have ever edited - I really mean it. The candidate is extremely faint and it required very long exposures time. 20 minutes of exposures even with a fast scope like the Takahashi epsilon 160 ed (F/3.3) seemed, at first, ridiculously not enough, even under one of the best astronomical site in Chili. For example, the Ha channel was noticeable with adequate stretch, whereas [O III] showed marginal results to such an extent that one could start questioning whether or not we shall put so much efforts to finally get "nothing". The 42h of integration of the [O III] ain't impressive. I wasn't really sure whether I would be able to pull out anything from the data. Nevertheless, by relying on various processing techniques (continuum subtraction, Pixelmath equation in PI, etc.), we finally managed to get something out of it. And by looking at the published image, we are confident that [O III] was worth the hassle.
Worth mentioning that we relied on two different scopes to gather the lights: most of Ha were collected by APO Team's TOA 150, whereas [O III] & RGB channels through Aygen's Epsilon 160 ed.
CS on behalf of the whole team.
Dana, Xavier, Marcel, APO Team, Aygen
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