Observation of Dracula’s Chivito (IRAS 23077+6707

[Jimi Lowrey]

Dracula’s Chivito
IRAS 23077+6707
RA 23 09 43
DEC +67 23 40
Type Protoplanetary Disk
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Early this morning just before the start of astronomical twilight I observed the protoplanetary disk IRAS 23077+6707. I was surprised at how small it appeared in my finder eyepiece it looked like a fuzzy star. The conditions were excellent with great transparency and seeing. I was able to use 1040X with rock steady stars. At 1040x I was able to see that it was elongated. I was also surprised as to the high surface brightness of the main disk. I could also see the nebula going near the star on the left. I only caught the dark lane twice and can not count it as a positive.
5485

I was not able to see Dracula’s fangs to the north and at the time I did not know to look for them. I also could see in the main disk stellar points that would come and go with the seeing. I am not sure what this is or if it is real. I plane to contact the author of a recent paper and ask about the knots I was seeing. I think with the high surface brightness of the main lobe it would be visible in many scopes. I will keep at it to see if I can see the fangs and stellar knots again.

[ScottH]

Thanks for your report, Jimi. Glad to hear that you saw some size to it. I saw it in early February shortly after the paper on it was published. It was so low in the sky that I was forced to use my 16-inch. With it, it looked like a 14.2-magnitude star. I fully expect to nab it with my 6-inch later this year when things cool off around here.

Scott H.

[Steve Gottlieb]

Congratulations on perhaps being the first to nab this one and see some structure!

The discovery paper ("Dracula's Chivito: Discovery of a Large Edge-on Protoplanetary Disk with Pan-STARRS (https://iopscience.iop.org/article/10.3847/2041-8213/ad43e3/pdf)") lists the apparent size as ~11" (ignoring the 'fangs') and states "An optical spectrum indicates that the obscured star is hot, most likely of type late A." So, this is apparently another Herbig Ae edge-on system like PDS 144N though larger than Gomez's Hamburger. In fact, the authors estimated the hot star is surrounded by a disk of diameter 3300 a.u.! (using a distance of ~300 pc or just under 1000 l.y.)

[Jimi Lowrey]

Akarsh enhanced a PanStarrs g band Image that show the knot that I have been seeing over the last several nights. Last night I tried a Sloan G filter and it made the knot easier to see. It is interesting that the lead author on a recent paper “Kristina Monsch” is not aware of the knot in the lobe. I wonder what it is. The search continues.

5488

[akarsh]

I took a look at Dracula's Chivito with my 28-inch f/4.1 last night. I was using a 4.5mm Morpheus which delivers about 650x magnification.

It appeared like an elongated fuzzy spot with an elongation at between -15° or -30° position angle east of north, i.e. NNW-SSE. On about three occasions, I may have sensed a "split" in that same direction of its elongation, as though it was a tight double star, but it was so weak I can't be sure—I can't make sense of what this could possibly be, if at all real. A faint star was seen to about 90° PA, i.e. due east. One other observer on the field also confirmed its diffuse nature looking through my scope. Hand-tracking at 67° declination was not bad even at this high power. I wish I had carried my 3.5mm Pentax so I could try higher power.

[Keith Rivich]

This past Sunday night (8/11) Larry Mitchell and I observed the Chivito at our dark site near Columbus, Tx. SQM 21.0. Excellent seeing. Scope was an 18" f4.5. Easy star hop from Iota Cep. Is the third star in a triangle of fainter stars. In my finder eyepiece (10mm Ehtos, 200x) was easy to recognize as a fat star, compared to the other two. With my 3.7 Ethos was easy to see as an elongated nebula with no structure. I tried to see Jimi's bright spot, no joy.

At the end of September we will be at our central Texas dark site with better observing conditions. Will give it a go with my 25" and a friends 30".

[drachi]

Yes, there are only three known Herbig Ae edge-on systems, DraChi is the largest, diameter actually 3300 au (300 pc x 11 arcsec), 1650 is the radius.