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Request Comparison Stars for Variable Star Charts

[Note: If your variable star has an existing sequence, even if it is only one comparison star, please request assistance via CHET. This page is only for variables that have NO comparison stars. Thank you.]

Due to the continued progress of AAVSOnet and our photometric surveys, the AAVSO Charts and Sequences Team is now revising and creating new sequences for variable stars at an amazing pace. If you wish to begin observing a variable star that does not have an AAVSO comparison star sequence, you can request one be made. These requests are frequently fulfilled in 48 hours or less if reliable photometry is available.
 
We have a simple process for accepting requests and tracking progress. If you think your star needs comparison stars, here is what you do.
 
CHECK FOR COMPARISON STARS FIRST
Enter the name of your star in the name field of the chart plotter, VSP. Check to see if comparison stars have already been assigned to this field in the appropriate range of magnitudes and proximity to your variable star. 

NEW VARIABLE DISCOVERIES MAY NOT BE RECOGNIZED
If VSP does not recognize the name of your star, it may not be in VSX, may be listed under another name, or may not have an AAVSO Unique Identifier (AUID) assigned to it yet. If this is the case, enter the coordinates of your variable star into the RA and Declination fields of VSP to plot a chart. Check to see if comparison stars have already been assigned to this field in the appropriate range of magnitudes and proximity to your variable star. 
 
GET YOUR STAR LISTED IN VSX
To find out if your star is included in VSX you should first search VSX by name, then by a coordinate search. If your star is not in VSX you should use the VSX Submission Form to get your star added to the database. 
 
Even if the star is already in VSX it may not have an AUID assigned so check for that also. You can request an AUID be assigned to an existing star by just clicking on the "Request AUID" button in the star's detail sheet in VSX.
 
PLEASE NOTE:  Unless the discovery is a new known transient object; you will not be able to have a sequence created until you have made a request to have the target included within the VSX data base.
 
SUBMIT YOUR REQUEST
Once you are sure no suitable comparison stars are available through VSP, and your star is in VSX, check the list of current sequence requests to see if calibration of the field of your star has already been requested. The list is here.
 
To make a formal request that a sequence be created for your variable star send an email to compstars@aavso.org and include the following information.
  • The name or designation of your variable star.
  • The coordinates of the variable star in decimal, sexagesimal or both formats (please include decimals)
  • The magnitude range of the variable, if known. (please include the Filter Letter; i.e. V, R, p, etc.....)
  • The Type of variable star (SRB, M, RCB, BLLAC, etc.....)
  • The Chart Scale you are able to work with (B, C, D, E, F, etc... or arcmin) for this request.
  • Whether you are a visual observer or a CCD (or other digital format) observer.
  • Indicate whether or not the request is “time sensitive or urgent”, as for a new or transient stellar event.
WE TELL YOU AUTOMATICALLY WHEN YOUR SEQUENCE IS READY!
You will receive an email notification when the new sequence is generated and available through the VSP.
 
If no suitable photometry is currently available your request will be added to a “queue” and periodically checked against survey progress to see when data has become available. You can view the list of fulfilled and outstanding requests here.
 
“Time sensitive or urgent” requests will be assigned the highest priority. If photometric data is not available a calibration request will be forwarded to AAVSOnet and a sequence produced as soon as data becomes available.
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484