The days and nights of a late variabilist

[Mircea]

Only last night, Monday, July 22, the skies were again more or less acceptable for variable star observations.
Actually I was just going out to cool off a bit after the heat of the day. And, because I'm a wimp, I didn't go out empty-handed but armed with my Saga 10x42mm. After a few glances, I decided not to miss the opportunity and observe variables.
Said and done, I observed the following thirteen variables: bet Lyr, R Lyr, del Cep, miu Cep, gam Cas, eta Aql, R Sct, U Del, EU Del, XY Lyr, g Her, R CrB, khi Cyg.

R CrB has been known ''for a long time''. It was discovered as a variable star in 1795 by Pigott, who also discovered eta Aql.
In this cycle I see that R CrB has stopped growing. It would have the ''right'' to rise to a maximum of 5.7 mv but, for some time, it has been lurking around magnitude 6mv.

R Lyr, was discovered later as a variable, in 1856 by John Baxendell. Also this is a difficult to observe variable star.
Last night I estimated it at 4.1mv. It's quite possible that the star was fainter. This is what the consensus among observers seems to be. But this much I can say with certainty: I have seen R Lyr with the naked eye but barely, barely - with averted vision - the comparison star ''43''.

The above brings me to this comment: Khi Cyg, which I estimated at 4.5mv, using as comparison stars Eta Cyg = ''39'' and Fi Cyg = ''47'', I failed to see it with the naked eye. Unlike R Lyr.

I received a message from Ms. Elizabeth Waagen of the AAVSO, in which I was informed that I had misrecorded the observations for Herschel's ''Garnet Star''. I recorded the observations under the index ''Mu Cep''. But this is a different star, the ''MU CEP'' star. As are U Del and EU Del in Dolphin. The server registered all my observations for miu Cep to MU CEP. Ooops !
That's why, from now on, I have to use the index ''miu Cep'' or ''MIU CEP''. Which, starting with the recording of last night's observation, I did.
I wrote for others to know, the correct index is miu Cep for that star.

Clear sky, Mircea

[lunator]

Hi Mircea

Very nice report.

cheers

Ian

[Mircea]

Thank you Ian

I am so sorry I started so late observing variable stars. I did not waisted my time at the telescope. I observed hundreds of Deep Sky objects, about one thousand double stars of which hundred are subarc.

But I had enough instructions and maps to start observing bright variable stars long before owning a telescope. 

When I was young, up until age 40, I had very good eyesight. But I didn't know it. I was seeing Epsilon Lyrae as double with the naked eyes.  There was no internet, so I thought it is the same with everybody. 

I say this not for  bragging but on the contrary, to show how stupid I was.  I could have do observations of  bright variable stars only with naked eye : Beta Lyr, Eta Aql, Alpha Her, Betelgeus and more.

But for irrational reasons I kept delaying. It is good, very good and interesting to have and to observe the heaven with telescopes.

What I missed is it is at least so interesting to observe variable stars. Even if I use only a hand held binocular.

To cut a long story short, I started observing variables at age 65 instead of age 25. Hence the title of the topic.

 

Clear sky, Mircea

[Mircea]

Last night, Thursday, July 25 I observed the variable stars R CrB, RR CrB, RX Boo, X Her, alf Her, bet Lyr and khi Cyg.

The comparisons were made with 10x50mm binoculars. But at alf Her and khi Cyg I used also naked eye estimations.

 

I estimated khi Cyg at 4.5mv by comparison with Eta Cyg = 39 and Phi Cyg = 47.
It was very interesting to see the star khi Cyg with the naked eye.
Between Albireo/ Beta Cyg and Eta Cyg only khi Cyg was visible with the naked eye. This formed with Eta Cyg and a star to the West a step right angled triangular asterism, with the right angle in Khi.
Today, I found out from Stellarium that this star, from the West of khi, was 8 Cyg which is the  comparison star 47 for R Lyrae.
I however, with the naked eye, did not saw Phi Cyg of 4.7mv between Albireo and Eta Cyg. I didn't even insisted, khi Cyg is at a third from Eta Cyg to Beta Cyg, that's where I focused my attention.
khi Cyg, 8 Cyg, R Lyr and star 44 I saw them with the naked eye. Observed this way, khi Cyg was slightly less bright than star 44.
Also through binoculars, at first glance, there was a difference between Phi Cyg and khi Cyg, in favor of khi.
The noted equation is:

a 3 khi 1 b

From which I derived the magnitude 4.5mv for the famous khi Cyg. With binoculars or the naked eye, khi appeared brighter than Phi Cyg = 47 but dimmer than star 44.

I attach the sketch of the observation. It is somewhat hard to explain but this naked eye observation gave me great joy.

 

Clear sky, Mircea

 

 

Edited yesterday at 09:13 by Mircea

[Mr Spock]

Variables are an interest of mine. I was starting with photometry a year ago but cloud has put paid to that. I just don't get enough clear skies to produce a meaningful light curve.

Back in the '80s and '90s I was doing estimates every three or four days. Now it would be three or four weeks. Tree growth has also restricted my field of view.

[JeremyS]

1 hour ago, Mr Spock said:

Variables are an interest of mine. I was starting with photometry a year ago but cloud has put paid to that. I just don't get enough clear skies to produce a meaningful light curve.

If you submit your observations to a variable star organisation they will be combined with other observers’ , making a decent light curve.

[Mr Spock]

10 minutes ago, JeremyS said:

If you submit your observations to a variable star organisation they will be combined with other observers’ , making a decent light curve.

Half the fun is constructing light curves myself. Something like V UMi can look pretty good quite quickly with enough clear skies.