6 easy doubles in Cassiopeia.

Hello, Darren.

I did check out 35 Cassiopeiae B on Vizie R, and I have done so again just now.
But I'm not seeing its spectral class at all.

So I have to ask you where is the information of our colourful star.
I definitely agree it is an M-class star.
And I am fascinated by this MK class.
I'm now wondering how many other MK stars there are in the sky.

By the way, I have found out who J. Stein is.
I got a reply on Cloudy Nights only a few hours ago.
Johan Stein was a Roman Catholic priest who lived from 1851 to 1951 and who studied many different subjects including discovering some new doubles stars.

And I have just requested once again what class 35 Cassiopeiae B is.
(We must remember the secondary is an optical companion to the primary.)
Perhaps this time someone will come back to me.

Thank you, Darren, for all your hard work.

Kindest regards,

Aubrey.

Hi Aubrey,

Lovely to hear from you, and it is the very least I can do - you've been so helpful and supportive of me over the past few months, and I'm learning an incredible amount about the night sky from you.

In terms of locating the spectral class for 35 Cassiopeiae B I discovered that 35 Cassiopeiae B can also be identified by BD +63 175.0. 

However when I entered this into Simbad, it did not reveal anything. So, I tried a few different approaches when entering the data into Sinbad. Once I entered BD+63175 (note no spaces), the following screen popped up:

simbad.u-strasbg.fr/simbad/sim-id?Ident=...min&submit=submit+id

Looking over this page I noted several other identifiers for 35 Cassiopeiae B. I clicked on several links, but it was 'PPM 12911' that revealed the spectral class.

For example, once I clicked the identifiers link for 'PPM 12911', or if i clicked on 'PPM 12911' - listed under the external archives heading - I was brought here:

vizier.u-strasbg.fr/viz-bin/VizieR-S?PPM%20%2012911

Once on this page I clicked the link showing the number '1' under the heading 'full', and it brought me here:

vizier.u-strasbg.fr/viz-bin/VizieR-5?-re...146/ppm1&recno=12911 .

I noticed the 'SP' heading on the left, and beside it on the right, it showed 'Spectral Type'. I was delighted! But I had one more step before I could confirm the Spectral Type. Eagerly, I clicked the link that reads '(src.spType)'

And presto, a window popped up with message: 'src.spType Spectral type MK'.

I've since discovered a slightly quicker way to get to the last point. For example on this page ( vizier.u-strasbg.fr/viz-bin/VizieR-S?PPM%2012911 ), if you click on 'SP' (11th column from the left); the following details appear:

UCD:SPECT_TYPE_GENERAL = Spectrum Classification 

UCD1+: src.spType = Spectral type MK

Type:ascii string(2)

dbType: char(2) (fixed-length left-adjusted String (2) (no leading blank allowed))
Flags:0x4003:   
VO_DISPLAY Column to display
VO_SELECT Column to select
VO_LEFTADJ Column can't start with blank

Please bear in mind, I am not sure whether what I have done has identified the correct spectral type of 35 Cassiopeiae B, but I thought I'd share what I've done with you and the other more knowledgeable members of the IFAS to decide whether I was barking-up-the-wrong-tree earlier.

Also, that's very interesting about Johan Stein - many thanks for that Aubrey!

Clear skies,

Darren.

Could the MK I see refer to the Morgan-Keenan system though?

Hello again, Darren.

Well - the plot thickens.
I have checked out your various links on Vizie R.

But unfortunately I have checked Wikipedia to see if such a spectral class as MK exists. It appears there is not such a class.

MK stands for Morgan Keenan. These 2 men, whose names are William W.Morgan and Philip C. Keenan issued stellar classifications which has the following classes: O, B, A, F, G, K and M. M -class stars are the coolest in temperature and they are red.

One guy from Oregon seems to be checking out my latest post on Cloudy Nights. He did inform me about Johan Stein.
So I suspect he will be figuring it out for me and everyone else.
I have heard nothing more from anyone else except you, Darren.

But I'm jaded now. But I will check out further tomorrow Thursday.

Clear skies from Aubrey.

That clears that up then Aubrey!

Kindest regards,

Darren.

Hi Aubrey, I hope you're keeping well. Over the past couple of days I've done some more work on that 35 Cassiopeiae B star. Since you posted the question about its colour it has really captured my interest, and has resulted in me learning lots about how to determine the colour index of stars. Not only does the webpage below explain the colour index of stars rather well, but it also describes how it may help us assign a colour classification to 35 Cassiopeiae B.  www.atnf.csiro.au/outreach/education/sen...otometry_colour.html For example, the Web page states that. CI = mb - mv.  The following Web page breaks it down into three steps to calculate the colour index:

www.astronomynotes.com/starprop/s5.htm

Here are the steps to determine the B-V color index:

1.Measure the apparent brightness (flux) with two different filters (B, V).

2. The flux of energy passing through the filter tells you the magnitude (brightness) at the wavelength of the filter.

3. Compute the magnitude difference of the two filters, B - V.

Using the data on SIMBAD for BD +63 175.0 / 35 Cassiopeiae B, we can enter the figures of 10.26 for B, and 8.43 for V into the formula i.e., CI = 10.26 - 8.43. This calculates as 1.83. Having watched some informative YouTube videos on colour / color index, and using the table on this webpage www.isthe.com/chongo/tech/astro/HR-temp-...table-byhrclass.html it would seem that 35 Cassiopeiae B is classified as an 'M' star. I have yet to work out whether it is an M4IV, M4V, or M4IV, that's assuming it is an M4 class in the first place. It may have to do with formulas on this page
astronomyonline.org/Science/Magnitude.asp ,

and something tells me Wien's law may help too.

 I'll keep you posted though.

 Kindest regards, and thank you for raising a most interesting question for us to engage with. 

Darren.