The Arrows of the Archer

[Francesco Meschia]

Greetings TACos,

I know that posting images is on an exception basis, but I'm very excited about a project that I just completed, and I’d like to share it with you.

I’ve been working on a backyard narrowband imaging project since late April. Dodging the moon and the frequent nighttime incursions of the cloudy marine layer, I collected almost a hundred hours over 32 days: three hours at a time, as dictated by the obstructions in my backyard at my target’s declination.

The target in question is found in Sagittarius at the coordinates of M24, the “Small Sagittarius Star Cloud”. But the target is most definitely not the “star cloud” part. It’s the gas clouds that form the backdrop for the stars of M24. Some of them are formed mostly by ionized Hydrogen, and give off the typical H-alpha red emission, others are cold atomic or molecular hydrogen, and cut dark shapes –notably, Barnard 92 and Barnard 93– and curtains in front of the overall glow. One of these curtains encroaches the shock waves of the ancient supernova remnant G013.3-01.3, forming incredible lightning-like streaks visible with different shapes in OIII, SII, and H-alpha wavelengths. These are the “arrows of Sagittarius".

The image is the result of almost 74 hours of H-alpha, SII, and OIII data, selected from the initial one hundred. It is a two panel mosaic, imaged through an Astro-Tech AT130EDT reduced to f/5.6, riding a Mach1GTO, with an ASI294MM camera and Baader narrowband filters. The data was initially combined in an HOO image, on which I overlaid the SII signal colorized in golden yellow.

The full resolution image is on Astrobin at https://app.astrobin.com/u/frankz?i=p0r9cs#fullscreen.

Comments, questions, and critique will be all very welcome.
Thanks,

Francesco

[Alex]

Awesome! More like Zeus Lightnings though :)

[Paul Alsing]

Well, that is just amazing!

---

From: sf-ba...@googlegroups.com <sf-ba...@googlegroups.com> on behalf of Francesco Meschia <francesc...@gmail.com>
Sent: Tuesday, July 21, 2026 9:18 PM
To: sf-ba...@googlegroups.com <sf-ba...@googlegroups.com>
Subject: [TAC] The Arrows of the Archer

 

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[Richard Navarrete]

That’s an incredible images! I’ve never seen one like it! Thanks so much for sharing.

Richard

Sent from the all new AOL app for iOS

[Jamie Dillon, DDK]

Francesco m'friend, that picture was worth the work. Those streaks are really eerie.

Rilke said it better, "Das Schönste is das Schrecklichste."

The most beautiful is also the most terrifying..

[Akarsh Simha]

Wow! I had no clue that this is what lurked behind M24!!

Fantastic, thanks for sharing!

Regards

Akarsh

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[KG]

Beautiful image Francesco!!! Never seen “arrows “ in DSOs before 😍
Gopal


> On Jul 21, 2026, at 10:33 PM, 'Richard Navarrete' via The Astronomy Connection (TAC) <sf-ba...@googlegroups.com> wrote:
>
> Francesco

[Mark]

Francesco,

Your effort producing this is where imaging crosses fully into fine art.  Stunning, and surprisingly unexpected!  Put it in a TAC-list images hall of fame.  Evocative of Henley's (et al) "this could be heaven or this could be hell". Encore, maestro!

I doubt the (mythical) "TAC Police" have a crack-down against posting images.  Perhaps chatter that is excessively technical about imaging has been discouraged.  Somebody should call with the cops and ask.

[Francesco Meschia]

> On Jul 21, 2026, at 22:04, Paul Alsing <pnal...@gmail.com> wrote:
>
> Well, that is just amazing!

> On Jul 21, 2026, at 22:32, 'Richard Navarrete' via The Astronomy Connection (TAC) <sf-ba...@googlegroups.com> wrote:
>
> That’s an incredible images! I’ve never seen one like it! Thanks so much for sharing.

> On Jul 22, 2026, at 08:31, KG <kgee...@gmail.com> wrote:
>
> Beautiful image Francesco!!! Never seen “arrows “ in DSOs before 😍
> Gopal

Thank you! I’m very glad that you all liked it.

> On Jul 22, 2026, at 00:32, Jamie Dillon, DDK <ngc1...@gmail.com> wrote:
>
> Francesco m'friend, that picture was worth the work. Those streaks are really eerie.
> Rilke said it better, "Das Schönste is das Schrecklichste."
> The most beautiful is also the most terrifying..

> On Jul 22, 2026, at 00:47, Akarsh Simha <akars...@gmail.com> wrote:
>
> Wow! I had no clue that this is what lurked behind M24!!
>
> Fantastic, thanks for sharing!

I know! I can only start to imagine what Bray Falls must have thought when he imaged this in optical for the first time, just five years ago. Finding something this beautiful, unexpected, and uncanny behind a mundane, well-know, every-night object.

> On Jul 23, 2026, at 03:46, Mark <itsmar...@gmail.com> wrote:
>
> Francesco,
>
> Your effort producing this is where imaging crosses fully into fine art. Stunning, and surprisingly unexpected! Put it in a TAC-list images hall of fame. Evocative of Henley's (et al) "this could be heaven or this could be hell". Encore, maestro!
>
> I doubt the (mythical) "TAC Police" have a crack-down against posting images. Perhaps chatter that is excessively technical about imaging has been discouraged. Somebody should call with the cops and ask.

Thank you, Mark!

Two weeks ago at Pinnacles I asked Mark Tomalonis to take a peek at M24 with his 22”. I wanted to see if I could tell B92 or B93 against the background stars. I had no luck, but I’m not visually familiar with the area and with that telescope’s FoV. But I remember reading here on TAC reports that they can be seen. I wonder if any hint of the “arrows” could be detected visually, by an observer accustomed with M24, with an OIII or UHC filter. I guess the glare from all the M24 stars would make it impossible, but it might be an interesting challenge.

Francesco

[Mark]

Did the arrows make you quiver when you saw them? ;-)  Are they why you chose the target, or were the arrows an unexpected surprise?

[Francesco Meschia]

On Jul 23, 2026, at 10:41 AM, Mark <itsmar...@gmail.com> wrote:

Did the arrows make you quiver when you saw them? ;-)  Are they why you chose the target, or were the arrows an unexpected surprise?

I knew about the arrows from Bray Falls’ “discovery” image (https://app.astrobin.com/i/hirvty?r=E). And  a couple of years ago I had imaged B92 and B93 in H-alpha by themselves (https://app.astrobin.com/i/cmonoj), but just this year it occurred to me that I could use the data as a starting point of a mosaic. It turned out to be a fairly small part of the overall data, but it gave me the idea – which is arguably the important thing.

Francesco

[Jamie Dillon, DDK]

Francesco, those two dark nebulae, B92 and 93, aren't hard to pick up inside of the Star Cloud. Sometime maybe I can point them out to you. NGC 6603 is another cool landmark in the midst of that spangle of stars, a compact bright open cluster that's physically inside M24.

I've spent a lot of hours staring at M24, including Wednesday night the 8th. Maybe with a monster scope with vast aperture those streaks could be detected. Remember you took 100 hours of data to gather that image.