Saturday, April 26, 2014

sunsets and galaxies

i'm observing this week with the 4-metre AAT telescope at siding spring observatory in NSW, australia.  we're using SAMI - the Sydney-AAO Multi-object Integral Field Unit.  so far the SAMI Survey has observed almost 700 galaxies with this unique technology - the biggest collection of galaxies to date observed with integral field spectroscopy.  exciting!

tonight provided a spectacular stormy sunset, then a little bit of observing before the clouds really thickened.  so i took some photos.

swirling storm of sunset and showers
 i love seeing rain falling in the distance.

sunset through the rain

observing companions for the week

i'm amazed as how much the instrument has improved since my last observing run with SAMI in 2011.

getting reacquainted with SAMI
we have to climb in that little space to plug all the bundles into the metal plate.

hanging out with SAMI at prime focus

the new technology includes the bundles of wires shown in orange and silver which plug into the metal plate.  in the silver cords are 61 optical fibres!  one bundle points at a single galaxy and captures its stars and gas swirling around in 61 different spots!  there are 13 of these galaxy hexabundles, making the survey uniquely efficient.

the new technology has been designed to fit inside one of the original base structures built in the 1970s. it looks solid, doesnt it?  i like all the manual dials, and there's even an eyepiece!

the only negative is that after observing with one configuration for 4 hours (in a series of 30 minute exposures), we have to climb into the cage in the middle of the night to manually unplug and replug a different plate.  it's an active observing campaign!

the necessity of plate-plugging in the middle of the night makes me very excited for the development of new AAO technology: the starbug micro-robots, which zoom around a plate (of glass) to position themselves independently and very quickly! 

1 comment:

Anonymous said...

I recently attended a talk by David Schlegel from Berkeley where he actually brought an aluminum plate to the talk, similar to the one in your pictures. It is very ignorant of me, but I had no idea that actual metal plates with (precision) holes in them were used to do galactic spectroscopy. Here's his abstract:

"Dark energy is a phenomena causing the Universe to expand more rapidly than can
be explained by Einstein's laws of gravity. Its discovery merited the 2011
Nobel Prize in Physics. The effects of dark energy imprint on large galaxy maps.

The Baryon Oscillation Spectroscopic Survey (BOSS) on the Sloan Telescope has
mapped 200 million galaxies in 2-D, and 1.5 million galaxies and quasars
in 3-D.

Dr. Schlegel will show how he and his team use BOSS to measure the scale of the
universe to percent-level precision at redshifts z=2.4, z=0.6 and z=0.3, from the
deceleration to acceleration driven by dark energy.

Recent maps are consistent with the "simplest" modification of Einstein's laws, the
addition of a cosmological constant."

Thanks for the post, you have a fun job!