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Posts by Mark McCaughrean

Indeed πŸ™‚ bsky.app/profile/mark...

2 weeks ago 0 0 0 0

Thanks, Markus – as you may have realised, I'm very rarely here on Bluesky, but that's good to know. Mastodon won't let you do so by default, I think.

2 weeks ago 1 0 1 0

Roughly, at least, I get a sub-latitude of -2.8ΒΊ, a sub-longitude of -13.9ΒΊ, and a distance (from the surface of Earth, I think) of ~10,000km. Hard to be more precise than that given the granularity of Celestia's response to my mouse. Oh, at 00:27:39 UTC.

2 weeks ago 1 1 1 0

Oh, & the time I ended up at was 00:30 UTC – I've since checked the EXIF information in the Artemis II image & it was taken at 00:27:39, presumably also UTC. Not bad πŸ€·β€β™‚οΈ

2 weeks ago 1 0 0 0

Sorry – I forgot to add ALT TEXT to that image & don't know how to edit Bluesky posts.

A screenshot from the Celestia app, with Earth in the middle and stars and constellations around it – it matches the orientation of the Artemis II shot quite well. Venus is seen at lower-right.

2 weeks ago 2 0 2 0

Two planets for the price of one πŸ™‚πŸ‘

Playing around in Celestia, I was able to identify the approximate time & orientation of that #Artemis II shot of Earth's nightside.

Revealing that the bright object at lower-right is Venus.

Thanks to @Nina_cried@mastodonapp.uk for suggesting that I check πŸ™‡β€β™‚οΈ

2 weeks ago 20 4 2 1

Ha – I felt sure that you'd have a professional interest in this, Jonathan πŸ™‚πŸ‘

2 weeks ago 2 0 1 0

When I first saw the image I thought "ugh – that's noisy". Then I looked more closely & saw all the faint stuff – the light levels are 400,000 lower than they would be under sunlight, after all, making this very impressive. Surprising then that NASA didn't mention it in their social media posts πŸ€·β€β™‚οΈ

2 weeks ago 0 0 0 0
A picture of the Earth from space illuminated by the full Moon – it looks like daylight, but this is the night side of the planet, not the day side. There are city lights on the continents and a green aurora towards the north and south poles, plus a faint rim of upper atmosphere airglow as well. You can also see a faint dark rim of the Artemis II window frame and the zodiacal light (probably). North is at lower-left and you can see North Africa, then Spain and Portugal on that side. You can see South America and North America on the right side.

A picture of the Earth from space illuminated by the full Moon – it looks like daylight, but this is the night side of the planet, not the day side. There are city lights on the continents and a green aurora towards the north and south poles, plus a faint rim of upper atmosphere airglow as well. You can also see a faint dark rim of the Artemis II window frame and the zodiacal light (probably). North is at lower-left and you can see North Africa, then Spain and Portugal on that side. You can see South America and North America on the right side.

You'll have seen this – Earth from #Artemis II en-route to the Moon.

But look again – it's Earth's *nightside*, lit by the near-full Moon, not the Sun πŸŒ•οΈ

The aurorae, airglow, stars, & city lights in Europe, Africa, & the Americas give the game away.

Cool.

NASA/Reid Wiseman
#Space #Photography

2 weeks ago 37 9 3 4
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The SW channel data were pretty poorly handled by the pipeline – we're working on custom processing to significantly improve the sky matching & 1/f noise, as well as saturation issues, especially with RAFGL5232. The S/N is low in several channels too, so we have work to do to get the science done.

2 weeks ago 1 0 0 0

Yeah, there are a few jets and outflows in the field, although not as many as we might have expected, given the dense molecular clouds & protostars. But then again, Sh 2-305 is pretty distant, so such things become harder to see.

2 weeks ago 1 0 0 0

Interesting – the people I interact with on Mastodon are generally lovely, apart from the odd person who squawks at me for not Content Warning spider pictures πŸ™„

But I agree, AstroTwitter was great & there are many people I miss from those days, in part because I’m very rarely here, perhaps.

2 weeks ago 1 0 1 0

I have to admit that I've never understood the objections to Mastodon – for me, it has been the perfect replacement for The Other Place, & comes with many advantages, not least no algorithmic timeline or undesired timeline intruders. Plus it can't be bought, a key lesson learned.

2 weeks ago 1 0 1 0

Thanks, Thomas – I've played with other colour combinations, but some of the SW data have a lot of 1/f noise & other banding straight out of the pipeline which we're working our way through fixing, & once that's done, we should have more colour combination options.

2 weeks ago 1 0 0 0

BTW, how on earth does anyone manage here on Bluesky with such a tight limit on characters in a post?! Sure, I know I tend to be rather ill-disciplined when it comes to editing down social media posts & email, but still ... 😬

That said, I'm not really here anyway, so bye again πŸ‘‹

2 weeks ago 6 0 2 0

This is a reduced version of the original data & only includes 3 (F182M, F300M, F360M) of the 8 NIRCam filters we have.

The short-wavelength data are pretty noisy & are taking a lot of work both to get good photometry for the stars, but also prettier pictures spanning a wider wavelength range.

2 weeks ago 2 0 1 0
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/cc @thocarp.bsky.social @yuvharpaz.bsky.social @melina-iras07572.bsky.social Aloha folks – just to let you know that these data go public tomorrow, but we're still working on them, as there tricky issues with saturation, banding, noise, etc.

Plese be sure to tag me if you also make & post images πŸ™‡β€β™‚οΈ

2 weeks ago 8 2 3 0
A colourful field of stars sprinkled across purple ionised gas and redder dust. The main cluster of stars is seen in a cavity to the upper right, while a very bright source surrounded by more gas and dust is seen in the lower left corner, with the characteristic six bright spikes due to diffraction in the optics of JWST. With a credit line in the lower-left corner that reads "Sharpless 305 & RAFGL5232 with JWST NIRCam / Credit: Mark McCaughrean, MPIA / NASA, ESA, CSA"

A colourful field of stars sprinkled across purple ionised gas and redder dust. The main cluster of stars is seen in a cavity to the upper right, while a very bright source surrounded by more gas and dust is seen in the lower left corner, with the characteristic six bright spikes due to diffraction in the optics of JWST. With a credit line in the lower-left corner that reads "Sharpless 305 & RAFGL5232 with JWST NIRCam / Credit: Mark McCaughrean, MPIA / NASA, ESA, CSA"

Sneak preview πŸ‘€

More of our #JWST data are going public tomorrow, for the galactic star-forming region Sharpless 305 & nearby massive protostar RAFGL5232.

Work in progress, as the data are rather problematic 😬

But as others will be quick to post images, here's our snapshot first πŸ˜‰

#Astronomy

2 weeks ago 440 67 8 7

Yes, I believe the working assumption is that they're proplyds, although the tails are a fair bit more ragged than those in Orion. Mike Kuhn et al. are close to submitting their paper & some of the same folk (Tyger Peake, Tom Haworth at QMUL) are working on the Rosette data with us.

2 weeks ago 1 0 0 0

Looks more like an interacting galaxy pair to me, given the asymmetry, the central peaks, & the extended emission on one side. But if Eric reckons that the literature matches an edge-on Class II disk, well, could be. We're working on the data presently.

1 month ago 5 0 0 0

Yep, we're working on it. It shares some characteristics with Orion-style ionised proplyds, but is very different in other ways. It's a known source, discovered with Spitzer & studied by Balog et al. But the WTF x-ray detection is spurious – careful checking of those data make that clear.

1 month ago 1 0 0 0

My gut feeling purely based on the morphology is that it's a pair of galaxies, not least given the extended nebulosity on one side & the two knots / nuclei.

But I don't know how readily the SED could be confused with an edge-on Class II system.

We're working on the data so will get back to it.

1 month ago 6 0 1 0

And ironically, the same agency is perfectly happy to publish the results of my image processing for missions like Rosetta, BepiColombo, JUICE, Gaia, & more – this is a JWST-specific policy.

I'd best not say more here, but I suspect you get my drift.

2 months ago 0 0 1 0

So I'm not about to turn over my hard-won individual filter mosaics for someone else to further process & composite in the name of "quality control". Ultimately, it just means nugatory work & fewer official image releases, which serves no-one well. Certainly not the agency I worked for for 15 yrs.

2 months ago 0 0 1 0

But I've been making colour composites from IR data for 40 years. It's one of the reasons I got involved with JWST in the first place & I'll take the quality of my images against anything "official" from JWST any day. Plus my HH288 colour scheme closely matches other HH object releases.

2 months ago 0 0 1 0

Well that exposes a raw nerve. Without naming names, let's just say that those agencies running JWST outreach refuse to publish any images made by anyone other than their own graphics people. I understand the need for quality control, but it's also clearly about policing the aesthetics.

2 months ago 1 0 1 0
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Thanks, Thomas – I'd appreciate that. I know that Bluesky doesn't offer much space (another reason I'm never here, preferring Mastodon's generosity & algorithmic purity), but I think it's reasonable to expect proper credit wherever images are posted.

2 months ago 0 0 0 0

It's also a pity, because I'm often impressed by the work such folk do, especially @geckzilla.bsky.social, for example. And when I asked her & others if I could use some of their work in my book, alongside ESA, NASA, ESO etc., the credits spread over 6.5 full pages. Again, it's not hard to do.

2 months ago 1 0 1 0

I'm not sure why "status" would make me immune from wanting to receive credit for the work I've done, both in winning the time for these observations & designing them. It's not hard to do (as you have shown), but some social media image processors seem to think it's irrelevant. Which I hate.

2 months ago 0 0 1 0

Bluntly, this is something I absolutely hate about some of the archive hounds. Again, I'm fine with the data being used, of course, but it really, really comes over as lazy & almost dishonest not to give appropriate credit. It's not hard to find the info. But hey, that's social media for you ...

2 months ago 0 0 0 0