Duncan WaldronJan 10, 2023
Mark McCaughrean

Well now, that’s a mighty strange thing 😳

A previously unknown, very extensive, low-surface brightness nebulosity near the Andromeda galaxy, M31, seen in the [OIII] emission line at 5007Å.

Discovered by Drechsler et al. in autumn last year using a 106mm refractor, showing again that not all astronomy needs the biggest telescopes 🔭

Perhaps in the halo of M31 & linked to its stellar streams? 🧐

More below 👇

https://iopscience.iop.org/article/10.3847/2515-5172/acaf7e

#astrodon #space #astronomy

Jan 9, 2023 at 11:18amMetatext
Show threadMark McCaughreanJan 9, 2023

HT to this toot by @clearskies, who points to a livestream happening soon with the first author of the paper, Marcel Drechsler.

https://astrodon.social/@clearskies/109658779859886145

Clear Skies 🔭 (@[email protected])

Attached: 1 image Today at 12:00 UTC, more about the stunning discovery by Marcel Drechsler et al. live on YouTube: https://www.youtube.com/watch?v=TEMXss1Qo4E The beans have already been spilled about this discovery, further data and high resolution imagery are inbound. https://iopscience.iop.org/article/10.3847/2515-5172/acaf7e?fbclid=IwAR12grzwnrY-GHKDBsR9sp9s3sMGPR-hQb2-TBZbi3cNsNfbCJW-98wkG6M #astronomy #keeplookingup

Astrodon - The Astro Community
Show threadDavid HonessJan 9, 2023
@markmccaughrean I'm not exactly sure which part of the image to look at...
Show threadMark McCaughreanJan 9, 2023
@davespice The Andromeda galaxy is on the right, over-exposed, while the wispy newly discovered nebulosity is on the left.
Show threadDavid HonessJan 9, 2023
@markmccaughrean thanks, I wasn't sure if I should be looking at the solid smudge to the right of Andromeda or the wispy area to the lower left of it
Show threadMark McCaughreanJan 9, 2023
@davespice Nope, the thing to the right is another galaxy, M110, a satellite of M31.
Show threadDavid GaladíEnríquez 🐀Jan 9, 2023
@markmccaughrean How sure are they that this is not an instrumental artifact?
Show threadMark McCaughreanJan 9, 2023
@DGaladi Have a look at the linked paper: they considered & dismissed instrumental artefacts. And to be honest, it really doesn't look like one: to my eye at least, it looks real.
Show threadVíctor R. RuizJan 9, 2023
@markmccaughrean The published color photo post has a lot of extra information by Drechsler's team. I don't think this is a M31 feature, would be a *very* large oxygen cloud that I don't think can be easily explained. I bet it's a local one. The [OIII] structures in Andromeda are really cool, though.
https://www.astrobin.com/1d8ivk/
NEW DISCOVERY: the M31 [OIII] emission arc /// STROTTNER-DRECHSLER-SAINTY OBJECT 1

An astrophotograph by Marcel Drechsler on AstroBin

AstroBin
Show threadMark McCaughreanJan 9, 2023
@vrruiz That's a great image & some very interesting information below it. They don't seem to agree with you re: the location, mind you, but this is all good cosmic discovery mystery stuff 🙂
Show threadDuncan WaldronJan 10, 2023
@markmccaughrean It does happen, but it's never not fascinating/surprising when such a modest instrument features in a discovery like this.