70 Ophiuchi

[Doley68]

After a description of this pair in the Sky at Night mag in June I thought I'd have a look before they drop too low as the year goes on. A very nice pair which I find interesting as both stars are red dwarfs which must be fairly local although I don't know their distance. Fairly simple split at around 4.5 secs. Nice.

[peterbolson]

Hi Doley

I also had a look at this the other night & estimated the separation about the same as you did. I then checked it in the stelledoppie website and found that the estimated separation for the AB component now is 1.88 arc seconds http://parkinson.dyndns.org/stelledoppie/index2.php?menu=31&iddoppia=72911 Can anyone explain this, as I'm sure it's not as close as this ( I'm going to recheck on the next clear night ! ).

By the way it gives the distance as 17 light years.

Peter

[Doley68]

Strange that it gives that separation as I would say it is a lot wider. There seems to be a lot of variation between different sources of info on doubles generally. Perhaps some of the quoted figures were from quite old measurements and the orbits have changed with faster orbiting pairs. 17 light years must make them one of the closer doubles to us them?