Celestia Forums

Joey P. wrote:I made a video explanation here on why I don't believe UY Scuti isn't the largest star: https://www.youtube.com/watch?v=OtEKBwJ0oXM

This value of 755 Solar radii is actually from Messineo and Brown et. al. (2019) from Stefan-Boltzmann law. I hand calculated the angular diameter estimate and if you actually went into and read the spreadsheet you'd notice that UY Sct is not anywhere near the top of the list (916 +- 201 Rsol). Current largest is HR 5171 A. But anyway this is the Celestia Origin thread - let Art Blos go back to work.

For your argument for the diameter of VY CMa - yes, VY CMa is one of the largest stars with an accurately defined radius. The 1,420 Rsol estimate comes from an angular diameter estimate, with an error of only 120 Rsol (Which is really good!). But, in the paper you referenced, nowhere does it say that the emission area extends out to 2000 Rsol. And even if it does, this can still only be confirmed in the infrared. You claim that this is in fact the visible emission area, which is a conclusion you cannot derive from this paper based on the fact that the telescope used for these observations, Herschel, is an infrared telescope.

So what is the largest star?
There have been recent estimates for NML Cygni and IRAS 05280-6910 that put them above 1600 Rsol, but I wouldn't trust this (Levesque's SBL estimates are not very accurate IMO). I would consider angular diameter estimates to be the most accurate. So what is the largest AD-measured star? Wittkowski et. al. (2017) gives 1575 +- 400 Rsol for V766 Centauri A/HR 5171 A, making HR 5171 A the largest star known with a reasonably well defined radius.

Again, take the time to look at the spreadsheet I linked. If you have any questions, you can easily PM me.

MrSpace43 wrote:I have a new Jupiter texture that is from before any spacecraft visited the planet that could be added if you like

Thanks for the Jupiter texture!

Added after 7 minutes 21 seconds:

fyr02 wrote:nowhere does it say that the emission area extends out to 2000 Rsol. And even if it does, this can still only be confirmed in the infrared.

That's exactly what I said (in the video). The paper says that the star's radius (R*) is 2,000 solar radii = 2,000 solar diameters.

And if you've already got such a sufficient list, then why don't you edit Wikipedia's list to fix it so that everyone can pick your beliefs up?

Joey P. wrote:Thanks for the Jupiter texture!

OMG you are a really stupid noob it was not for you it was for Celestia Origins. Delete it now if you have it in your files because you have no permission to use any of my textures.

MrSpace43 wrote:OMG you are a really stupid noob it was not for you it was for Celestia Origins. Delete it now if you have it in your files because you have no permission to use any of my textures.

I get that you don't want Joey using your textures, but if you make textures available for download there's nothing to stop people from using them for their own personal use. Apparently you actually went and removed the textures from your post, but they'll still be in the next release of Celestia Origin.

CM1215 wrote:
Not allowed to use them for what exactly? I can understand that they can't be redistributed, but frankly there's nothing to stop one person from using the textures for one of his own creations (as long as they don't put it up for download anywhere). I could download the textures and put them on my own exoplanets, and as long as I don't put them up for download somewhere, you'd never know...

Again, I get triggered easily. But just to avoid another issue, I'ma stop and just let us move on...

Joey P. wrote:The paper says that the star's radius (R*) is 2,000 solar radii = 2,000 solar diameters.

Again, even if this is true, we can only confirm this in the infrared, because Herschel is an infrared telescope
The "emission area" talked about in the paper is referring to SiO maser emission, which happens due to interactions in a gas cloud involving water/silicon dioxide molecules, therefore, 2000 rsol refers to the area in which the energy from VY CMa is strong enough to create astrophysical masers that can be detectable from earth, not that actual radius of the star.

Joey P. wrote:That's exactly what I said (in the video)

The paper does not say this. searching "2000" in the paper brings up J2000 coordinates and 2000 Kelvins, but no 2000 Rsol. If you can point me to where it does say an estimate for the radius, please do so. In addition, the HIFI instrument used in the paper is actually not a camera (i.e, it cannot directly measure the diameter of VY CMa and is only a wavelength-separating spectrometer used to detect maser emissions (which again means that the emission radius refers to the infrared maser emission radius). Again, please take the time to thoroughly read and understand the papers you cite.

In your video, you also say that Wikipedia editors are unwilling to use this paper. No they are not, they have actually cited this paper on the largest stars page to describe VY CMa's environment. And I'm not surprised that they didn't accept your reasoning, considering that you are a person who is infamous on Wikipedia for having a large amounts of sockpuppets and meatpuppets, which is against Wikipedia's rules.

As for me editing Wikipedia itself, I don't actually have the technical knowledge to edit the table of values with inline citations, whereas I'm used to having references from a single source be the basis for a table. Hope that clears things up.

fyr02 wrote:And I'm not surprised that they didn't accept your reasoning, considering that you are a person who is infamous on Wikipedia for having a large amounts of sockpuppets and meatpuppets, which is against Wikipedia's rules.

As for me editing Wikipedia itself, I don't actually have the technical knowledge to edit the table of values with inline citations, whereas I'm used to having references from a single source be the basis for a table. Hope that clears things up.

You can use the VisualEditor. It is automatic when it comes to proper referencing formats.

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Additionally, is Celestia Origin going to be full-scientific only, or will it include science fiction elements?

Joey P. wrote:Additionally, is Celestia Origin going to be full-scientific only, or will it include science fiction elements?

Fictitious objects, such as "Death Star" or "Endurance", we do not add. Russell's teapot and Space lift included in CO as an exception.

I look forward to trying this out. Thanks to everyone involved!

How long does it take to install? I've had the installer working for at least 30 minutes, and it seems to be stuck at "models/toutatis.3ds in Celestia's installation doesn't exist, skipping...". I say seems because I do see the size of the folder is changing.

Orion96 wrote:How long does it take to install? I've had the installer working for at least 30 minutes, and it seems to be stuck at "models/toutatis.3ds in Celestia's installation doesn't exist, skipping...". I say seems because I do see the size of the file is changing.

I don't remember exactly how long, but what you describe definitely doesn't happen for me. What operating system are you using?

I'm using Windows 10 64 bit.

Update: It's continuing. I just had to be patient.

Orion96 wrote:I'm using Windows 10 64 bit.

Same here. That's odd. Did you make sure to run the install script with administrator permissions?

Orion96 wrote:Update: It's continuing. I just had to be patient.

Edit: Oh okay.

fyr02 wrote:I've made a list of Largest Stars values with sources; the values in green and blue are the most accurate, the non-highlighted ones I would not suggest changing. Just posting this for resourcefulness and a possible radius edit.
https://docs.google.com/spreadsheets/d/1LmzrfDEwzv9ldTofTgu4iOxGCw9SlOCsZ6tHynAcMnE/edit?usp=sharing

I have made a new video on the largest stars here using data from that table:
https://youtu.be/ToY49gQOv70
VY CMa & VV Cep A are still at the top (I'm optimistic about stellar radii).

Added "NEAR Shoemaker".

Doubt-

I have download all of these,
If a new version comes out , will i have to download all of these again?Or will it be a small patch like file?

Any help will be highly appreciated

ArchitPasayat2008 wrote:Doubt-

I have download all of these,
If a new version comes out , will i have to download all of these again?Or will it be a small patch like file?

Any help will be highly appreciated

Unfortunately, yes. You have to download it all over again, so it's best to either delete your old Celestia or better yet, download a new one and then download the latest version there