Friday, September 25, 2015

Thems The Breaks....

Sara Camnasio (left) , Munazza Alam (center), and Haley Fica 
(right) are excited outside the DuPont telescope as we prepared
for night 1 of observing. 
As the Rolling Stones said so profoundly, "You Can't Always Get What You Want".  This observing run is the epitome of that sentiment.  I'm currently on Night 3 of 3 at Las Campanas with my undergraduate assistants Haley Fica, Sara Camnasio, and Munazza Alam.  On Night 1 we had high humidity which would not allow us to open.  We wished for winds to help clear the clouds and that wish was granted!  The winds picked up and pushed the clouds away from the DuPont telescope and lowered the humidity.  However the winds overdid their job and we couldn't open because they were too strong.  Around 1am Chile time, they died down enough so we could open but the seeing was a large 2 arcseconds (translate big fat stars that are bad for science).  It improved only slightly throughout the night.  I was attempting to get the ever important epochs on some very close by brown dwarfs for which I can measure their distances with my multitude of data.  Unfortunately, I'm not sure Night 1 data will be very useful.

Sara shows the sad picture of the 
observing conditions at Magellan 
on Night 2.  We never opened 
due to high humidity and freezing 
temperatures which left ice on
the dome.
Staying positive, we went into Night 2 with an excited fervor to be using one of the big telescopes on the mountain, the 6.5m Baade telescope.  The students were singing "I'm so excited" as we did afternoon calibrations.  Unfortunately high humidity was once again our enemy.  The wind attempted to clear the ugly clouds that sat on top of us but couldn't quite get them away at a fast enough rate.  When the sky finally cleared and the humidity dropped (ish), the temperature plummeted to a nasty -0.8 degrees.  It was cold.  And that cold froze the moisture from the clouds leaving a layer of ice on the railings between the telescopes and on the dome itself making it impossible to open.  Night 2 was a wash.
Despite poor observing conditions, my awesome trio of female
undergraduates celebrated seeing a 6.5m world class telescope.
Not to be defeated we went into Night 3 with a smile and a determined attitude to get some data!  There were some clouds on the horizon during calibrations but we were not going to let those get in our way.  By sunset the sky was looking pretty good.  But when we opened the seeing was an astonishingly bad 5 arcseconds (translate REALLY big fat stars that are bad for science)!!!!  What on Earth was going on!  I was pretty sure I needed to sacrifice a student (kidding of course). After 2 hours of sitting on a bright target we had to close because the clouds had closed in and covered the moon.  The wind then moved things and we opened.  Which is where we are now. Collecting as many photons as we can in the last hour of the night as we battle with the wind and clouds to stay open and reach our faintest (and most exciting) brown dwarf targets.

We need some luck.


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