Tue, 10/18/2022 - 19:12
AAVSO Alert Notice 795 announces an observing campaign on the intermediate polar FO Aqr in support of upcoming HST observations. Please see the notice for details and observing instructions.
There are threads for this campaign under the following AAVSO forums:
- Campaigns and Observation Reports: https://www.aavso.org/fo-aqr-hst-campaign-2022
- Cataclysmic Variables: https://www.aavso.org/fo-aqr-hst-campaign-2022-01
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
I wanted to thank everyone that added FO Aqr to their observation list the past couple of nights. There was a definite uptick in the number of observations of FO and the range of filters being used to collect data. I was even able to get some photometry (through some clouds) using Notre Dame's Krizmanich Telescope. It overlooks the stadium, so Saturday evening will have an extra background from the lights.
STScI has clear the first visit to FO Aqr based on your observations this past week. Whew!
The first HST visit will go ahead tonight: Start time: 27 Oct 2022 02:40:47; End time: 27 Oct 2022 06:45:02
It may clear off in Indiana and I will try to do some simultaneous time-series observations.
****The second visit needs a go/no-go decision Friday morning, so additional photometry tonight and Thursday night are needed to clear those UV observations with HST.
Thank you all for your help on getting the first visit approved.
STScI has approved the second COS visit to FO Aqr scheduled for tonight (Friday night/Saturday morning). Thank you all for your observations that made this approval possible.
I downloaded the 3-orbit spectrum from the first visit and there are emission lines there...success! We'll have to see how the spectrum varies over the binary orbit.
The second (and final) visit will occur between:
Start time: 29 Oct 2022 05:27:30 End time: 29 Oct 2022 07:56:32
FO Aqr will be too low for me at the start of this window to get any simultaneous observations from South Bend. It might be up for a bit for people further west.
The good news: HST successfully observed FO Aqr last night. The average UV spectrum looks great. Thank you all for your work in getting the observation approved by the COS safety folks at STScI.
The bad news: the spectrum from the first visit was not as nice as the second visit. I was pondering this problem when an email from STScI arrived telling me that the guide star did not achieve lock on the first visit and this may have compromised the data. Indeed, a comparison between the two spectra shows that the second visit had a 300 times higher count rate than the first visit. Apparently FO Aqr was off the slit and only a small fraction of the light was making to the detector.
I will send in a request to have the observations repeated. So I may be back one of these days asking for your help again.