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Can't load in data from file

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Can't load in data from file

Whenever I want to open a .csv file with VStar I get this message:

"Observation Read Error - No Observations for the specified period."

But I have never specified a period to begin with? I just start the program open my file and it doesn't work.

I'm really new to all of this stuff and I'm sure I'm just making some Rookie mistake but would anyone help me out pls? Thanks a lot anyway!

David Benn
David Benn's picture
Can't load in data from file


Can you attach the file you are trying to load?

"Period" here means "duration" not period of star. Having said this, that message is less than useful and is on the list of things to change.


Hey David,

Hey David,

it's not an error with one particular file, it's with all of the ones I tried, but I attached them.

Thanks for the help!

Data Format

It appears all these csv files are from ASASSN. There is an asassn plug in for precisely this reason. VStar doesn't know a priori what each column is and has no way to determine it. So it assumes column 1 is time, column 2 is magnitude, and column 3 is error (I'm pretty sure this is true, David please correct me if I'm wrong). ASASSN has column 2 as camera, and column 3 as filter. If you remove these two columns, then I think it will load correctly.

Bert Pablo
Staff Astronomer, AAVSO

drob's picture
Data Format

I have opened only first two files and it appears that your data is in the wrong format.  The proper formatate canbe found on page 9 of the VStar manual (Version 2.21.1).  For format is Julian Date, Magnitude, Uncertainty and Observers code.

Hope that this helps,




Davidjau's picture
Data format

I have tried the first two files and it opens it without problems. remember to specify the correct survey in the dialog box (ASAS-SN).
Attached images.



File upload: 
David Benn
David Benn's picture
Data Format

Thanks Bert, David, Robert for responding to Florian.

What you say is right Bert. For more details, the default "Download or Simple" format is specified in the user manual on page 9.

I wrote the version version of the ASAS-SN plugin but Max and Cliff have extended it since.

I loaded each attached CSV (e.g. via the Request URL button in the file chooser (user manual, p 12), rather than by downloading the files Florian attached.

The ASAS-SN format has changed over time. 

The first 3 (in order of attachment) are certainly ASAS-SN format files. The first and third are ASAS-SN "Sky Patrol" format files. The second is an ASAS-SN Photometry DB format file.

I'm not sure what the 4th file's format is. Did you get them all from ASAS-SN Florian?

See also these links for more detail about the ASAS-SN plugin:


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