My guess is that this object is embedded in a cloud of dust which becomes visible when hit by ionised gas from the nebula. It's a bit frustrating that APOD calls this object the "Butterfly nebula" when it is more often called the "Bug nebula". There is already another planetary n...
Yes, my point exactly - new pic but the same old caption. There's absolutely nothing wrong with recycling captions (or the pic if it's good!) but in this case I think that the caption needs to be updated.
The caption says "It is still unknown which star or stars ionize the red-glowing hydrogen gas". This was identified in 2005 as the heavily obscured O5 V star 2MASS J205551.25+435224.6, which lies behind the LDN 935 dark cloud that appears to separate the North American nebula from the Peli...
Galaxy Map is a wonderful site!!! Who runs it? I do, actually. :oops: On the history of the Gould Belt ... this is all pretty controversial, and I wouldn't put this on my own site, but here's a capsule speculation: Star formation appears to have started about 50 million years ago inside a molecular...
how do those clouds form? The first generation of stars were formed from hydrogen, helium and probably a bit of lithium. So I don't think there were dust clouds in the early universe. Within those stars, heaver elements, including carbon and silicon, formed. These were released as stars evolved int...
To add a bit more information, the dust cloud complex pictured here: http://antwrp.gsfc.nasa.gov/apod/ap081208.html is "officially" called DCld 301.0-08.6 by SIMBAD and it is catalogued in this paper here: http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1986A%26AS...63...27H This paper po...
Hi Jim, I've looked more carefully at the Spitzer mosaic and I have to say I was wrong about the visibility of the Perseus arm. You can actually see several prominent first quadrant Perseus arm objects including W49 (at 43 degrees) and 3C 397W (at 41 degrees). So even though the Perseus arm is more ...
What's more, a lot of our view of what we could see is blocked by dust or the fact that some objects obscure other objects. The fact that astronomers can figure any patterns out of what we see is amazing! Having said that, the new NASA image was designed to illustrate some specific conclusions from ...
Hi Henk, Most of your questions are answered on my site. I'd start with these three articles: http://galaxymap.org/drupal/node/33 http://galaxymap.org/drupal/node/32 http://galaxymap.org/drupal/node/90 In terms of the concentrations that you noticed. Yes, they are all connected to major Milky Way st...
Hi Jim, In the Spitzer image you can see objects in the Scutum-Centaurus arm and in the Sagittarius, Carina and Norma arcs. (I'll call them arcs now that they are not recognised - at least by NASA - as full arms.) You can't see the Perseus arm in the Spitzer images as it is too far away and obscured...
In case anyone is wondering what they are seeing when they look at the Spitzer mosaic, I've uploaded a labelled diagram I did of the MSX data a while back. MSX is a less detailed but more comprehensive infrared survey of the entire galactic plane from +5 to -5 degrees in latitude. It is also useful ...
Andy, the object on the left (partially visible on the linked image) is the Lagoon nebula (M8, Sh 2-25), and the one at the right is the War and Peace nebula (NGC 6357, Sh 2-11, W22). Both look quite impressive in infrared. John - yes the image is centred on the galactic nucleus. Kevin Kevin Jardine...
Just to be complete - I mentioned before that the Lynds and O'Neil distance estimate of 1680 parsecs = 5500 light years is based on an estimate of the distance to HD 164514. This is the supergiant that illuminates the blue reflection nebula north of the main Trifid nebula. This is also not quite cor...
I've followed up on my question on the distance to the Trifid nebula and looked at the differences between the Kohoutek et..al. and Kharchenko et.al. estimates to the distance of NGC 6514, the Trifid star cluster. First, I was incorrect about the Kohoutek et..al. study - it is not based on full clus...
I've always imagined that starships would carry along their own Hubble-like photon collectors and instantly process the images. So the beautiful images would appear on the starship bridge - and include infrared, ultraviolet, radio, gamma, x-rays - the whole works. The Captain would say things like &...
It is not at all out of line to suggest scrubbing stars from certain astronomical images. In fact, scientists do it themselves if they want to examine the fine detail of a nebula for example. (This is not to suggest that the good astronomers who run the APOD would have the time to do it themselves.)...
The Spitzer paper mostly discusses the nebula itself, but there is a paragraph on the region to the north (which is the area you mention - as you say, the APOD has rotated the original image): Just north of the Trifid Nebula is a region containing a surprising number of protostars (R.A. 18h02m42.28s...
Yes, this is an amazing image that seems to reveal quite a few new objects. I'm curious about the distance estimate that was used in the caption. The caption says that Trifid nebula "lies only 5,500 light-years away". This seems to be (quite reasonably) taken from the 2006 Spitzer paper th...
Just for the record, the Wikipedia was wrong about the Gum Nebula. The Gum Nebula is Gum 12 in Gum's famous catalog. Gum 56 is the Prawn Nebula - so APOD is correct.
I will see if I can get the Wikipedia article corrected.
I see that Simbad agrees with your identification of Gum 56 with the Prawn nebula (IC 4628). But a quick google finds that many other sites say that Gum 56 is the catalog number for *the* Gum nebula, the close, big one that includes the Vela supernova remnant. This includes the Wikipedia article on ...