Third Night: Hitting our Stride

IRTF captured at sunset.

The shadow of Mauna Kea as the sun was setting.

We're now three nights into my time on the summit, and four nights in to the run as a whole.  We've hit our stride now, having ironed out all the various bugs in the first couple of night and tested new settings for the TEXES instrument.  For me, it's been a rather steep learning curve, both for the control of the instrument and for the reduction we're doing in realtime.  The TEXES team have a piece of software called PIPE that we're using the reduce, calibrate and plot the data so we can see it, and that seems to be my main job each night as Tommy Greathouse controls the observations themselves.   John Lacy and Glenn Orton have now left, so there are just a few of us up here each night.

The next few nights fall into a set routine, repeating settings and wavelengths to map our 360 degrees of longitude on a variety of targets, from Jupiter and Io to Saturn.  So we began at 6pm on Jupiter, mapping wave activity in the troposphere and stratosphere using methane and ethane emission bands (we can certainly see waves at mid-latitudes on Jupiter right now).  Then we continued Con Tsang's program of Io observations between 9pm and midnight by observing Io's Jupiter-facing hemisphere, where they expect to see very little SO2 in the atmosphere due to negligible frost and volcanic activity there.  More rather faint galaxy spectra were obtained between midnight and 3am, and then Saturn occupied the final three hours.  Hydrocarbon mapping of the northern hemisphere caught the beacon again for a second night, but this time it was quickly setting on the limb, and had moved off the Earth-facing hemisphere by the end of the night.

At the start of the night I took the car and drove up to the ridge next to Gemini-North to catch the sunset.  It was a lovely evening, with a carpet of clouds laid out below me, and the peaks of Maui in the distance.  I captured images not only of the gorgeous sunset, but also of the shadow of the volcano behind us, rising to a dark peak over the clouds.  During the long integrations on all these targets, we were reducing data from previous nights, and talking about the best ways to calibrate the TEXES dataset (see my separate post here).