Talk:Rho Cassiopeiae

Accuracy
I filled in the starbox template with the most accurate information I could find, but it conflicts with the text to a significant degree. &mdash; RJH 23:40, 10 March 2006 (UTC)

near future?
"Astronomers predict Rho Cassiopeiae may become a supernova in the near future because it will soon have consumed most of its nuclear fuel."

What is considered "near future" in the context of this article? Stellar relative near future or human-lifespan relative near future? Other? A tangible number would help clarify. —Preceding unsigned comment added by Zerotta (talk • contribs) 16:18, 5 February 2008 (UTC)


 * I think "near future" happens to equal 12,000 years, counted from 2003. Rursus dixit. ( m bork3 !) 21:30, 31 March 2011 (UTC)

Goldilocks zone
Even though its surface temperature is similar to the Sun, its comfort zone for an Earthlike planet would be 450 AU, or 15 times the average distance from the sun to Neptune.

Surely for a star whose surface temperature halves every 50 years while coughing out 10,000 earth masses of burning gas, the concept of a goldilocks zone is a bit of a fallacy? An orbit at 450AU would take a fair few of these eruptions to complete, so I daresay an Earthlike planet around Rho Cas would have to have a somewhat eccentric, flower-shaped orbit which brings it closer to the star after an eruption, lest it freeze over. Unless anyone wants to contest this, I'm removing this statement. - file lake  shoe  16:42, 17 April 2009 (UTC)

Distance
How has the distance to this star been determined? Obviously it is too far for a reasonable parallax measurement. --Proofreader (talk) 20:52, 29 May 2009 (UTC)

According to Hipparcos data ( parallax for Rho Cas is 0.28 (error 0.21)  which works out to be 3571 (+/- 2678) parsecs. Obviously far but the error is ridiculously big. Most astronomers assume its a member of the Cas OB5 association which has a rough distance of 2.5 kpc (+/- 500 pc).

The absolute magnitude has been calculated incorrectly in the main article. If Rho Cas was at 4 kpc it would have an absolute mag of ~-10! This assumes a reddening (light absorbed by dust)of about 1.7 magnitudes.At the distance above (2.5kpc) the absolute mag is about -9 somewhat closer to what is accepted in the literature. Tirion's Sky Catalog 2000.0 quotes -9.4. --Jb291266 (talk) 22:13, 20 April 2010 (UTC)

Magnitude
This star is located at around 1,000 light years according to the text, and is of absolute magnitude -9.5. Deneb (α Cygni) is of absolute magnitude -8.38 (so less bright) and located at around 2,600 light years according to Deneb, yet it is much brighter in our skies than ρ Cassiopeiae.

I suppose this is due to interstellar absorption by dust between us and ρ Cassiopeiae (and less or no dust between us and Deneb), but I don’t find any information about this anywhere. Does anyone have a reference? Thanks in advance! CielProfond (talk) 22:52, 9 July 2021 (UTC)

Distance
The distance of 1,000 parsecs in the article uses a very noisy Gaia DR2 parallax, which has a significance of astrometric noise at 497, where anything above 2 is probably significant. The value can be seen at this page, selecting all tables, selecting all columns and filling the parameter Source with "1998148532777850880" (the DR2 sourcs for this star). sepsi is the significance of astometric noise. Unfortunately there is no Gaia DR3 parallax, actually this paper says that it is negative and therefore unhelpful.

There are any other reliable distances about this star? InTheAstronomy32 (talk) 15:52, 3 June 2024 (UTC)


 * this paper mentions a distance of 2.5±0.5 kpc and appears to be the best that we have. InTheAstronomy32 (talk) 16:01, 3 June 2024 (UTC)