Starship Asterisk*

The NGC 2244 star cluster (whose most massive members ionize the Rosette Nebula and make it glow) is not evolved. I'm probably not using the terminology correctly, but by 'evolved' I mean the nebula is at a late stage of star formation. The stars in the core are on the main sequence and stellar win...

It really has that much oxygen (blue) here? What's the source of this huge oxygen production? There are a couple possibilities I can think of here, hopefully someone more knowledgeable can shed more light on this. The Rosette is an evolved star forming nebulae, stellar winds from the young bright s...

There is an interesting image on this page with hydrogen-line radio data added, which shows the gas bridge between these galaxies: https://theastroenthusiast.com/the-interacting-triplet-of-m81-m82-and-ngc-3077-an-ultra-deep-219-hour-collaboration-detailing-the-nuanced-interaction-remnants-and-galact...

Interesting stuff. Looking at the linked paper, an ongoing spectrographic study will help determine if this object is outside our galaxy. "A spectrum of the [O iii] emission arc would offer radial velocity information which could establish an association with M31 and its halo. A follow-up spect...

Ann wrote: ↑Thu Jan 12, 2023 11:55 am IC 348 looks bigger than NGC 1333 to me.

Ann

IC 348 is huge and intricate in IR, as you can from this unWISE image (W1 & W2 bands).

As for NGC 1333, for me it's conclusive proof that Balrogs have wings.

jagganath69 wrote: ↑Sun Jan 08, 2023 7:08 am What does the BROWN shade mean (Polonium et al) ?

These are all elements with very short half-lives, so they barely exist in nature.

AVAO wrote: ↑Fri Nov 18, 2022 5:56 am
original picture sources & copyrights: https://www.astrobin.com/dg54ro &
NASA ESA (ALLWISE color)

watch this zoom in video too: https://www.youtube.com/watch?v=kCNVBykGB1s&t=59s

Thanks for providing the context, I was wondering where this spectacular protostar resides.

Path to the Pillars https://live.staticflickr.com/65535/52440102595_1f39e96107_h.jpg A high-res version is here . A composite image to show where the famous Pillars of Creation reside in the sky. The first two images were taken from Caradon Observatory on the edge of Bodmin Moor, an International D...

I would have loved to see an APOD that was a collection of many different comets and their tails! :D ☄️ I'd recommend Damien Peach's comet galley page if you haven't seen it Ann. C/2012 S1 (ISON) is a particularly interesting one. https://www.damianpeach.com/comet_index.htm Maybe he could be approa...

<<In 1922, Edwin Hubble proposed that Deneb may be responsible for lighting up the North America Nebula, but it soon became apparent that it is not hot enough: Deneb has a surface temperature of 8,500 K, while the nebula’s spectrum shows it is being heated by a star hotter than 30,000 K. In additio...

This is my favourite image of the galactic core, from MeerKAT.

If there is any OIII in the Flame Nebula, I'd say it is in the center of the embedded cluster. But I have no idea how much there might be. I think the presence of OIII requires a very hot star and a "rarefied medium" around the hot star. Ann Yes, that's what I'm getting at, looking for OI...

I think that's plausible Ann. To see if the ionizing source is the same as the source of the reflection nebulosity I'd have a go at comparing the morphology of an Ha image with the green channel. (I have the data sitting on a disc so I'll take a look if I can get around to it.) Also, is there much O...

no more random than any image of atomic nucleus you've ever seen. And while black holes are certainly complex, they're not complex to the point where we absolutely can't even imagine what one would look like: we can and that's roughly what you see in the APOD. An actual image of a black hole was pr...

Imagine being the first astronomer on a world in M87 to realise that the orbit of your star system will take it through the jet... Imagine being a climatologist/ecologist on our own world realizing that he/she will live long enough to experience the Anthropocene . Yes, sadly we don't have to look f...

Imagine being the first astronomer on a world in M87 to realise that the orbit of your star system will take it through the jet... This is not a very active black hole, and the relativistic jets are quite small, just a few thousand light years. It is unlikely that any stars that close to the center...

Imagine being the first astronomer on a world in M87 to realise that the orbit of your star system will take it through the jet...

I'm not quite sure what that last thing is, but it doesn't sound much like what I'm describing. All I'm talking about is what happens in most nebulas that are illuminated by a combination of emission and reflection. I've been following the thread with interest and I don't see any real disagreement ...

Look at nebulas NGC 3603 and NGC 3576 in the picture at left. They look like they existed side by side as a "double nebula". But in fact NGC 3603 is located thousands of light-years behind NGC 3576 - probably some 14,000 light-years behind! And look at the color of these two nebulas. NGC ...

Do we know if Alnitak is in front of or behind the nebula?

That's a striking rendition of the Flame Nebula, looks more like a painting. Unfortunately it's been flipped left-right.

Yes Ann, I've often wondered about the yellow colour of the Flame Nebula. I'm guessing dust has something to do with it?

Digging into the paper I linked to, Pleiades cluster members were found stretching over about 110 light years. This gives an angular size of over 14 degrees, assuming I'm understanding correctly. "We calculated the tidal radius as in Sect. 4.1, deriving 11.6 pc, with a total of 1248 sources. Th...

Thanks Ann. Shows that Gaia can go beyond identifying cluster members but can pick out probably past members too and find past interactions.

Something I've wondered about, what is the true extent of the Pleiades please? As I understand it we can easily pick out the dense core but it extends much further than this. I'd have thought data from Gaia could answer this question, I found this paper online but don't understand the scale on the d...

RocketRon wrote: ↑Sun Mar 28, 2021 5:18 am And since we now know its not allowed/possible to wash clothes in space,
it would have been a very grimy set of clothes inside indeed !?

Re-entry would have had something of a scouring effect, perhaps as high as two micro-Zwickys.