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Today was the 365th day I’ve spent at Las Campanas Observatory. You only have to go back to May 18th, 2012 to find the first. So 16.7% of my life has been on this mountain over the last 6 years.

It was an interesting 1-year day too. Of course, it was Empanada Sunday. According to my records, my average length of stay has ben 21 days, so ~3 Empanada Sunday’s per visit X 17 visits = 51 total Empanada Sundays in my life so far. Here’s what just one looks like:

My longest stay here has been 44 days. That was what I call the “Death Run”. Late May and early June, telescope open for 13+ hr a night, horrific winds, 5 weeks straight of observing. When Katie reminisces (not fondly) about it, she says “you could sleep, eat, or shower. Pick 1.” Well, to commemorate that on mine and LCO’s 1 year anniversary, here’s a picture from the wind gauge tonight:

We managed to open a couple of times. But when we did it was pretty crappy

Hi All,

Yesterday we mounted the SAO’s Giant Magellan Telescope (GMT) dispersed fringe sensor prototype (Proto3 — Brian McLeod’s 3rd version — it keeps getting better). This is a complex set of infrared cameras and optics that mimic 3 of the GMT primary mirrors boundaries. It is basically a 2 slit experiment that interferes light (to make “fringes”) from the edge of each primary (where they almost touch) of the GMT. In this manner we hope to measure if one primary is slightly higher (out of phase in piston) with respect to the other primary — this will be a critical measurement to enable a diffraction-limited GMT in the future.

So that means we turned Magellan/MagAO into just 3 pairs of slits and look at the interference between the pairs. See photo below of the Magellan pupil with these 3 slits pairs superimposed over it.

The fringes produced by the 2 slits are then dispersed in the vertical direction — in this way it can capture/measure up to ~40 microns of piston between GMT segments.

In the photo below you can see the 1.1-1.3 micron (infrared) spectra of the fringes, here MagAO was locked on 300 modes.

Jan Kansky took this great photo of Proto3 (the box above Derek) mounted on the back of the NAS

The main test of the system is to understand the “fringe behavior” when Proto 3 looks far away from the guide star that MagAO is correcting. Below we show a video of what the fringes look like when the fringes come from a star that is 6 arcminutes away from the guide star.

So in keeping with tonight’s theme — here is a Fringe song about the TV show of the same name:

Here is a different version:

It’s the fourteenth sixteenth blog post for this run, but it’s my first ever post for the MagAO blog. I’m Joseph Long, a just-finished-first-year graduate student in astronomy working with Dr. (Astr.?) Jared Males. I’m helping out as an AO operator for part of this run, though it may be more accurate to say everyone else is helping me learn to operate MagAO.

Tonight is a bit of a change from the last few nights: Clio has gone on a vacation to the storage building and a new instrument has been installed. Brian McLeod and the rest of the Giant Magellan Telescope co-phasing prototype instrument team are all here, and we’re quickly running out of chairs. The instrument they bolted on today is designed to demonstrate the ability to phase the Giant Magellan Telescope’s primary mirror segments by treating the 6.5 m Regular Magellan Telescope’s single primary as if it were segmented. (“It had better be in phase!” — Jared) Dedicated readers may recall Derek Kopon’s post from December 2015, which explains some of the motivation and techniques for this project.

MagAO grew up with VisAO and is good friends with Clio, but is less well-acquainted with the phasing prototype. This means a lot of playing around with stage offsets and rotator angles to get light into the instrument. After fifteen or twenty minutes of manually commanding stage positions in 0.2 mm increments, one’s mind starts wandering to new user-interface paradigms that don’t involve punching in absolute stage positions every few seconds. (Fortunately, Laird and Jared have a workaround: get the graduate student to do it.)

This whole experience brings back memories of KAPAO and Pomona College, but I have to say Las Campanas has the superior facilities. I’m speaking, of course, about the lodging and food.

I’m not sure I ate anything but fistfuls of chocolate-covered espresso beans while on Table Mountain as an undergraduate, so I feel very well taken care of here at Las Campanas.

As someone who grew up in a big city, I can sometimes forget what the night sky is supposed to look like. (Except for the occasional citywide blackout, I remember the night sky as a comforting dark orange.) The view of the Milky Way before moonrise here is spectacular. Of course, I spend most of my night looking at this kind of thing:

The night sky is hard to photograph (just ask the Clio and VisAO PIs), so instead I’ll leave you with a photo of the Magellan Clay telescope greeting the sunrise.

Because blog posts have rules, I have a thematically appropriate song by Spoon: “I Turn My Camera On”…

…and a cover, by Rock Kills Kid…

Ahhhhh. It’s nice to finally not have clouds to fight with. We also have been getting some of that patented LCO 0.5″ seeing.

This is what we’ve been dealing with:

We finally got to see the Southern Sky in all its glory:

Hedwig visits every couple of nights:

Tonight was Clio’s last night of the run.

You might hear this song played by the Los Alamos Big Band on special occasions:

Bing Crosby died on my birthday. My Mom blames me.

Thanks to our many resourceful observers posting over the last several days, I have accumulated photos to share. This is an LCO lifestyle post.

Song of the day, just cuz I like it:


[Song/Image description: Derniere Danse by Indila]

[Song/Image description: Cover of Derniere Danse by Hristina]

Update: Now that we are in the US, apparently the first version isn’t available here, so here is the other version: