- The following is an archived discussion of the DYK nomination of the article below. Please do not modify this page. Subsequent comments should be made on the appropriate discussion page (such as this nomination's talk page, the article's talk page or Wikipedia talk:Did you know), unless there is consensus to re-open the discussion at this page. No further edits should be made to this page.
The result was: promoted by Cwmhiraeth (talk) 06:32, 20 February 2017 (UTC)
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RCW 36
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Image of the RCW 36 star-forming region at X-ray (blue) and infrared (green and red) wavelengths.
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that new stars are currently forming in the RCW 36 star cluster?Source: "Star formation in RCW 36 is currently ongoing. Some protostellar cores (Giannini et al. 2012, MTHM13) and a UCHII region (Walsh et al. 1998) are found in the region where the far- infrared flux peaks (region II/III, Fig. 4f). The column density in this region is very high (Hill et al. 2011), consistent with the – fact that radiation only escapes from its surface and not from the embedded sources. It is entirely possible that new massive stars are being formed within this thick column of dust. Star for- mation is actively taking place at the forefront of this region, as demonstrated by the presence of two HH objects (Ellerbroek et al. 2013). Their positioning with respect to the cloud is reminiscent of the HH 901 and HH 902 jets emerging from the pillars north of the cluster Trumpler 14 in the Carina Nebula (Smith et al. 2010)." [1]- ALT1:... that more than 300 young stars in RCW 36 have been detected by the Chandra X-ray Observatory? Source: On page 2, Table 1 "337 X-ray young stars in RCW 36" ([2])
- ALT2:
... that the density of stars in the star-forming region RCW 36 is about 2 million times greater than in the Sun's neighborhood, and this density is sufficient for close encounters between stars to affect planet formation?Source 1: Page 2, Table 1. "log density = 5.5 [stars per cubic parsec] for RCW 36 B" ([3]) Source 2: [Gregersen, Erik. The Milky Way and beyond. The Rosen Publishing Group. pp. 35–36. ISBN 1-61530-053-8.] Source 3: "For example, at a density of 10^4 pc^-3, protostars and T Tauri stars with large disks are likely to have a close encounter on the order of their envelope or disk radius on a timescale of 10^5 yr, while classical T Tauri disk radius interactions occur much less often, on a timescale of 10^7 yr." ([4])
- Reviewed: Judith Hemmendinger
5x expanded by OtterAM (talk). Self-nominated at 21:55, 2 January 2017 (UTC).
- Comment only RCW 36 is 2300 light years away - is it reasonable to use "currently" about something taking place 2300 years ago? Edwardx (talk) 00:18, 3 January 2017 (UTC)
- The source on which the hook is based also uses the word "currently" in its description. The timescale for star formation is much longer than the ~2000 years that it would take for light from this star cluster to reach us. For example see Protostar#Observed classes of young stars – even the shortest timescale is a factor of 5 longer than the light travel time from this cluster, and the longer star-formation timescales are a factor of 1000 greater. For the astrophysical determination of whether or not star formation is ongoing, the source does not mention the light travel time as it is insignificant in this case. Generally in astronomy, light travel time is usually not mentioned for objects in the local universe, and it's only for objects at cosmological distances (e.g. hundreds of millions of light years) that it matters scientifically. OtterAM (talk) 04:13, 3 January 2017 (UTC)
Sufficiently expanded, recent enough. Image looks OK, but caption should be improved to say what the features shown in the different colours are rather than just what frequency they were observed at. ALT1 looks good as the hook (better than the main one). ALT2 could also work, but is too long and wordy at the moment - perhaps remove the comparison with the solar density from it. Also with ALT2, the ref (on page 10) says "perhaps planet formation", and is more definite about the likely effects on disk evolution, so perhaps say "affect protoplanetary disks" instead of planet formation. The content of the article looks good overall (nice work @OtterAM!); I have detailed comments that I'll post on the talk page (now at Talk:RCW_36#Suggestions.2Fcomments). If ALT2 can be revised, then we could use that, otherwise we can run with ALT1. Thanks. Mike Peel (talk) 08:38, 7 January 2017 (UTC)
- I have struck ALT2, because at 218 characters it is well above the 200 character max for DYK. If it is revised as a new ALT hook, please be sure it is under 200 characters. Thanks. BlueMoonset (talk) 07:35, 9 January 2017 (UTC)
- I've been doing a bit of traveling, so sorry for the slow progress. I'll devote time tomorrow morning to finishing up the rest of the changes suggested. OtterAM (talk) 13:51, 1 February 2017 (UTC)
- I've made a number of changes to the article based on @Mike Peel:'s comments on Talk:RCW_36 and have replied to each of his comments. I've also provided a new caption (one paragraph above) for the image. ALT1 would be fine with me. Let me know if there are any more concerns. Thanks! OtterAM (talk) 12:52, 19 February 2017 (UTC)
