BeSS 10 years statistics

As weather is not cooperating for several weeks now, I took the time to look at BeSS database. I focused on high resolution (R>5000) spectra as this seems to me the top BeSS priority. I also selected Halpha (6562-6563A domain) spectra as this also seems the top priority to me - even if multiple order echelle spectra counting is better for me! :-)

2017 has been the best year ever with close to 1900 spectra acquired that year, 50 more than the record year of 2013 and significantly better than the average of the last five years.

Note that while BeSS database has been up and running since 2007, Christian Buil has data acquired before that time so the acquisition year start back in 1999. Joan Guarro Flo is helped by a very good weather and a very good focus on Be stars. I have done my best year in 2017 with the help of the mount refurbishment and some work on my overall observing efficiency, my photon time increasing from 60% of the dome open time to more than 85% now.

Here is the details for the all-time top 10 observers:

We can say that an amateur observer focused on Be stars should be able to acquired 500-600 spectra per year. Top 10 observers, on their individual record year, have acquired in average 250 Be star spectra. If I look at their 3 best years, they average 200 spectra per year.


Cumulated, we all together crossed last year the 15000 spectra milestone:

One month without observing and 2017 wrap up

Summer and automn were great in terms of weather. Winter not so good as after a long observing night on december 6th. I had only one hour and no serious observation on december 12th... so I was happy last night when I was able to catch more than eight hours observing time. I acquired close to seven hours of "photon time", with 8 additional Be star spectra added on my account on BeSS database!

The night didn't start well as after several weeks, the computer went through the last Windows 10 update and PRISM was updated as well. After the update the Atik cameras didn't work so I had to update the drivers. Then all seem to work ok. My first GoTo was off by one FOV (Field Of View) in diagonal - not so bad.


2017 was a wonderful year and I actually did it in less than six monhs. The observatory has been working great and I am continuously improving it making it more efficient.

I have done the calibration frames moving to 1x1 binning with the echelle Atik 460ex camera. I went down to -20°C on very cold nights (-15°C last night). I also took several reference stars so I have now instrumental responses for several elevations or air masses.


As for the stats, here they are:

Almost 500 observations (more than 11000 individual orders!), lot of them of Be stars so my stats in BeSS went up the roof. I ended the year with first position in terms of number of spectra/orders and fifth position in terms of number of Halpha observations (it will be hrd to get to first position there as Joan and Carl have excellent weather and much better than I have... but wait and see!):

One interesting thing is that in 2017, there has been 25159 spectra/orders observed. I took 10304 of those so 41%!

For Halpha alone, only amateur spectra with a resolving power R>5000 (ie High Resolution), 1893 observations were made and I too 448 so 24%. Joan Guarro Flo took 200 (11%) and Carl Sawicki took 154 (8%).


I also made some stats on the SNR for the Be stars alone and it is interesting to see the small difference between binning 1x1 and inning 2x2. Thing is that with binning 1x1, I often take only one single exposure for bright targets where he spectrum doesn't saturate in one 1200 secondes exposure.

Here is the SNR measured on the final spectral profile versus the Be star V magnitude (using ISIS, FWHM tool, SNR2 measurement on the continuum close to Halpha):

The following graphs show (for binning 2x2 and 1x1) the total exposure time that would be required to reach a SNR=100 on the continuum:

Last but not least, the graphs below show the individual exposure time depending on the Be star V magnitude. It shifted to te left by about one magnitude (not so obvious, more data should tell it more clearly in the future):

New battery for the Pulsar Dome

Weather has been terrible since last observation (dec 12th) but when I tried to open the dome last night, I realized the battery was dead with a broken cell. Reason may be the -7°C we had in december and a low charge...

Anyway, I went to buy a replacement today (I switched to a 12V/22Ah instrad of the 18Ah that was installed initially). I also added a BluSolar PWM Light Charge Controller. I'll see if the solar panel finally work and having it not directly on the battery is better - time will tell.