Search found 91 matches

by Knight of Clear Skies
Thu Jan 12, 2023 12:28 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Stardust in Perseus (2023 Jan 12)
Replies: 6
Views: 2022

Re: APOD: Stardust in Perseus (2023 Jan 12)

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.
by Knight of Clear Skies
Sun Jan 08, 2023 10:02 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Where Your Elements Came From (2023 Jan 08)
Replies: 37
Views: 8241

Re: APOD: Where Your Elements Came From (2023 Jan 08)

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.
by Knight of Clear Skies
Fri Nov 18, 2022 9:48 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Protostar within L1527 (2022 Nov 18)
Replies: 16
Views: 4356

Re: APOD: The Protostar within L1527 (2022 Nov 18)

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.
by Knight of Clear Skies
Wed Oct 19, 2022 5:29 pm
Forum: The Observation Deck: Latest Sky Photography
Topic: Submissions: 2022 October
Replies: 138
Views: 249355

Re: Submissions: 2022 October

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...
by Knight of Clear Skies
Thu Dec 09, 2021 9:16 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Comet Hale-Bopp Over Val Parola Pass (2021 Dec 08)
Replies: 4
Views: 2969

Re: APOD: Comet Hale-Bopp Over Val Parola Pass (2021 Dec 08)

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...
by Knight of Clear Skies
Thu Sep 16, 2021 6:56 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: North America and the Pelican (2021 Sep 16)
Replies: 8
Views: 3233

Re: How a Pelican got in my Bajamars(tar) I don't know.

<<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...
by Knight of Clear Skies
Sat Apr 17, 2021 4:38 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Inside the Flame Nebula (2021 Apr 17)
Replies: 6
Views: 3025

Re: APOD: Inside the Flame Nebula (2021 Apr 17)

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...
by Knight of Clear Skies
Sat Apr 17, 2021 9:07 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Inside the Flame Nebula (2021 Apr 17)
Replies: 6
Views: 3025

Re: APOD: Inside the Flame Nebula (2021 Apr 17)

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...
by Knight of Clear Skies
Fri Apr 16, 2021 10:17 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Doubly Warped World of Binary... (2021 Apr 16)
Replies: 28
Views: 13411

Re: APOD: The Doubly Warped World of Binary... (2021 Apr 16)

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...
by Knight of Clear Skies
Fri Apr 16, 2021 8:04 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)
Replies: 21
Views: 6454

Re: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)

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...
by Knight of Clear Skies
Fri Apr 16, 2021 8:03 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)
Replies: 21
Views: 6454

Re: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)

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...
by Knight of Clear Skies
Thu Apr 15, 2021 6:45 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)
Replies: 21
Views: 6454

Re: APOD: The Galaxy, the Jet, and a Famous... (2021 Apr 15)

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...
by Knight of Clear Skies
Tue Apr 13, 2021 7:20 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 12835

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

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 ...
by Knight of Clear Skies
Tue Apr 13, 2021 6:38 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 12835

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

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 ...
by Knight of Clear Skies
Mon Apr 12, 2021 3:31 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 12835

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

Do we know if Alnitak is in front of or behind the nebula?
by Knight of Clear Skies
Mon Apr 12, 2021 7:10 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Alnitak and the Flame Nebula (2021 Apr 12)
Replies: 43
Views: 12835

Re: APOD: Alnitak and the Flame Nebula (2021 Apr 12)

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?
by Knight of Clear Skies
Tue Apr 06, 2021 10:21 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)
Replies: 14
Views: 4471

Re: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)

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...
by Knight of Clear Skies
Tue Apr 06, 2021 10:02 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)
Replies: 14
Views: 4471

Re: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)

Thanks Ann. Shows that Gaia can go beyond identifying cluster members but can pick out probably past members too and find past interactions.
by Knight of Clear Skies
Tue Apr 06, 2021 7:57 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)
Replies: 14
Views: 4471

Re: APOD: Mars and the Pleiades Beyond Vinegar... (2021 Apr 06)

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...
by Knight of Clear Skies
Sun Mar 28, 2021 7:31 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: SuitSat-1: A Spacesuit Floats Free (2021 Mar 28)
Replies: 23
Views: 9451

Re: APOD: SuitSat-1: A Spacesuit Floats Free (2021 Mar 28)

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.
by Knight of Clear Skies
Wed Mar 24, 2021 9:11 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Mars over Duddo Stone Circle (2021 Mar 23)
Replies: 12
Views: 4849

Re: APOD: Mars over Duddo Stone Circle (2021 Mar 23)

Love that starry sky over the Hurlers! I can see the Double Cluster, the Andromeda Galaxy and Cassiopeia! Ann Thanks, think this was just a 30 second snap with a wide angle lens, with a little light-painting on the foreground. Not much light pollution up on the moors. I now use Sequator for easy st...
by Knight of Clear Skies
Tue Mar 23, 2021 2:16 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Meteor Fireballs in Light and Sound (2021 Mar 15)
Replies: 14
Views: 5687

Re: APOD: Meteor Fireballs in Light and Sound (2021 Mar 15)

neufer wrote: Tue Mar 23, 2021 1:48 pm Yes, probably around a kiloton of TNT.
Thanks neufer.
by Knight of Clear Skies
Tue Mar 23, 2021 11:25 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Antikythera Mechanism (2021 Mar 21)
Replies: 59
Views: 34370

Re: APOD: The Antikythera Mechanism (2021 Mar 21)

If anyone is interested in a book on the Antikythera Mechanism I can recommend 'Decoding the Heavens' by Jo Marchant.
by Knight of Clear Skies
Tue Mar 23, 2021 10:50 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Meteor Fireballs in Light and Sound (2021 Mar 15)
Replies: 14
Views: 5687

Re: APOD: Meteor Fireballs in Light and Sound (2021 Mar 15)

A daytime fireball was heard over much of South-West England on Saturday afternoon . Can anyone give me some idea of how much energy was released please? I'm guessing something like this is above a kiloton. Hopefully it will be possible to find some fragments, as with the Winchcombe meteor on 28th F...