Rainy, dark Oxford at six in the morning in February. The word ‘bleak’ springs to mind, as I
hurry for the Heathrow airport bus.
Rain thundering against the windows as we hurtle down the M40. But not to worry, as I’m lucky enough to be
heading to the Big Island of Hawaii to spend a week observing from the summit
of Mauna Kea. I’ll be using a high
resolution spectrometer called TEXES, mounted on NASA’s Infrared Telescope
facility, to probe the atmospheres of Jupiter and Saturn in the
thermal-infrared. The idea is to move
far beyond the photometric imaging or low resolution spectroscopy that I’m used
to, to a regime where the individual spectral lines can be resolved and used to
probe regions of these atmospheres that are typically hidden from our
view. This is all a bit of an
experiment, so I’ve decided to share these experiences with you,
oh-lucky-reader-whoever-you-are (if, indeed, anyone ever does read this!). So be prepared for an onslaught of blog posts
(if sleep deprivation and altitude sickness don’t torpedo my attempts).
It’s the start of
February 2013, and it’s been five years since my last trip to Hawaii. Several factors have kept me away – family
life, the increasing simplicity of operating instruments remotely, and the use
of telescopes in even more remote climes, such as the high deserts of
Chile. Last time was a single half-night
of Jupiter observations from the Japanese Subaru telescope in early 2008. I’d only just moved out to Pasadena to take
up my NASA postdoctoral fellowship at JPL, and my boss Glenn Orton wanted me to
join him on an observing run.
It’s far easier to visit Hawaii from LA, as the trip from
Oxford involves 30 minutes to reach Oxford bus station, 90 minutes on a coach
to Heathrow, two hours in the airport, twelve hours crossing the Atlantic and
mainland USA, three hours exploring the wonders of LAX, then six hours out over
the Pacific ocean to land in a wet and rainy Hilo on the Big Island. This time, however, we have a whole slew of
nights with the TEXES instrument, so it’s worth my while to make the trip. I’ve never used this instrument directly
before, so it’ll be a steep learning curve for me (particularly for my
O2-deprived brain at 14000 ft), but I’ll have the expert, Tommy Greathouse from
the Southwest Research Institute in Texas, there to guide me. We’re all hoping for clear skies and good
conditions, and plenty of data to write papers on for the next few years!
This run is really important to those of us specialising in
thermal imaging of planetary atmospheres.
The thermal-IR is the best way to unravel the effects of temperature,
composition and clouds in a planetary atmosphere, providing insights into their
meteorology, seasonal phenomena, and bulk compositions. With the exception of the Cassini/CIRS
experiment orbiting Saturn, we have no other way to study these topics other
than ground-based telescopes. For a
multitude of reasons, there are very few thermal infrared instruments working
right now (instruments on the VLT and IRTF are having problems, and Gemini is no
longer offering its two mid-infrared instruments). So these TEXES observations might be our only
shot at thermal imaging of Jupiter and Saturn in the next few months, to
capture the events currently unfolding in their dynamic atmospheres. More than enough reason for me to suffer the
long trip halfway around our planet. Now
I’ll shut up and watch an inflight movie.....
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