Skip to main content

CVNET circular

4 posts / 0 new
Last post
roe's picture
CVNET circular

I get the CVNET circular in my email basket.  How do I interpret all the data?  Here is a snippet'

HS 1857+7127(UG+E) 151(20) 158(22) <152(23) 160(26) 160(27) 161(29) 161(30)
          155(31) 162(6) 166(7) 163(8) 167(9) 172(11) 169(12) 171(13)
          168(14) 168(15) 159(16) PYG,ROE,SRIC,SXN

The HS 1857+7127(UG+E) and the observer codes are obvious but what about the rest?

FRF's picture
re: CVNET circular

These are the daily average brightnesses of the given variable:

161(30) 155(31) 162(6)

This means: 30 May: 16.1; 31 May: 15,5; 6 June: 16.2


SXN's picture
CVNET Circular

The star name is given first, then the type of variable in parenthesis. The following numbers are the magnitude of the variable for each of the prior 30 days (in parenthesis). The magnitudes are calculated by averaging the observations in the AID.     

SXN's picture
CVNET Circular continued

For the sake of clarity I should add:

The magnitudes listed are averaged from Johnson V and visual data combined, as if they are the same.
If there is no data for the date there is no circular entry.
If only upper limits (less than) observations are reported the faintest magnitude is used.

The CV Circular is available, and you can subscribe to it here:

Some uses for this Circular:

You can see at a glance what your star of interest has been doing for the last 30 days.
You can see which stars are heavily observed and which receive little attention. 
You can use it to help make decisions in building your own observing program.
You can see who is observing the same stars as you, and if you wish you can communicate with them on shared interests.
You can sometimes identify discrepant or misreported data and help to sort things out with headquarters and the observers.

There is also a circular for LPVs that performs in exactly the same manor available at

I've updated the home page for each circular to explain how they work and what they are based on this conversation, so thanks for pointing out that deficiency, Jim!

Log in to post comments
AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484