AAVSO Alert Notice 777 announces an observing campaign beginning immediately on the delta Sct variable EH Lib. Observations are critical now through at least the night of June 09/10. Please see the notice for details and instructions.
There are threads for this campaign under the following forums:
Please subscribe to these threads if you are participating in the campaign so you can be updated. Join in the discussion or ask questions there!
Many thanks, and Good observing,
Elizabeth O. Waagen, AAVSO HQ
Hello. I observed EH Lib on five nights last summer, looking to measure times of maximum for a period change study. Three nights are reduced, and two remain to be reduced. I was wondering if these would be helpful for the EH Lib campaign or else because they are from last June and so are not. I can reduce the two remaining nights myself fairy quickly and upload them to the database (if I can figure out how to format them).
Our main objective with asking for photometry was to allow us to get the proper phase for the spectral data. As you point out there is an issue with period changes here. So, concurrent data is the most helpful, but all data can play a roll. Our challenge now might be the weather on Wednesday and Thursday nights. Thanks for letting me know about the data.
I obtained BVRI over an interval of 2.5 hours last night, about 3 - minute repeat period for the filter set. Some high thin clouds but SNRs pretty good. Will upload to AAVSO db when processed, transformed, and checked.
Jim DeYoung (DEY)
Thanks for letting us know. We are now hope to get the clear weather we need to get the spectral data. Even a little photometry will help get our data lined up.
Last night, fighting a little with the clouds, I was also able to take the descent and the ascent of the curve in multifilter. The data is already submitted to the AAVSO. I also tried some spectra in Bin1 and Bin2 with an Alpy-600, I'm not yet at the start of the season adjustments, so it's not ready, but I calculated a "shift" of -4.4692Å (204.16 km/s) on the H-Alpha line (6562.8Å), is it possible?
It was a brief moment of observation, finally, the clouds won!
I just upload a serie of observation from last night following your request. I Hope it will be usefull for you. Best regards
José Luis (HJLA)