We’re on the third and final night of the intermission between the MagAO-X on-sky nights. Tomorrow (which is now today), we’ll spin the tertiary around to feed starlight down the waiting maw of MagAO-X for the third time.
In the meantime, we’ve continued to work out bugs, close and refine the loop on our internal source, and argue about future improvements to be made on the instrument. This mostly just looks like fatigued astronomers and grad students frowning at their laptops, which has been covered in some detail in the last two blog posts. Instead, I present a modest selection of images taken around LCO in the last 24 hours:
We managed to pull ourselves out of bed before dinner to run (well, drive) up to the Clay for a quick group photo in front of the instrument.
Today’s song is “Hang on Little Tomato” by Pink Martini.
Today, we present the eyepiece of MagAO-X!! Back in the day, astronomy was only ever done with an eyepiece. But now, we have far better technology than our own eyeballs to do science. If Galileo or Edwin Hubble were looking down at us, they would probably be jealous.
Nowadays, telescopes rarely have eyepieces, because the instruments use science cameras to take data instead. But if an instrument does have an eyepiece, it is probably just for fun, so we can feel like Hubble looking through a telescope with our own eyes. That is pretty much why we have an eyepiece for MagAO-X! So that we can see the power of extreme adaptive optics with our own eyes…it’s pretty cool!
The MagAO-X eyepiece was generously donated by the Close family, and it is a work of art. It has a shiny plaque that mimics the traditional tailpiece of a classic telescope.
Today, Laird, Maggie, and I tweaked the alignment of the eyepiece optics to make sure it is ready for our next nights on-sky (December 7 and 8). We are planning on using it to see the power of MagAO-X with our own eyes! I took a picture with my smart phone through the eyepiece with our internal light source on. The rainbows you see in the image are due to our 2,000 actuator deformable mirror. There are so many actuators over a small distance that the mirror acts like a diffraction grating!
Jared and Joseph did some work on the electronics rack today. Now we have one additional GPU in the RTC specifically for predictive control calculations.
For the rest of the night, Jared and Olivier continued working on closed loop calibrations and predictive control while Laird, Maggie, Kyle, Joseph and I worked on other MagAO-X stuff.
It is officially Christmas in Chile! They put up a Christmas tree in the lodge.
Also someone has been feeding one of the zorros, so we have a friendly fox that hangs out by the lodge now. I managed to capture a picture of him hanging out.
And of course, a picture of the sunset for the beginning of our “day.”
This title is somewhat misleading, after observing last night most of the team spent the whole day sleeping and stayed up working all of tonight. Olivier and I were the only ones to make it to lunch today and he put it best: “We value food more than the others, or perhaps we value sleep less.” For me, it’s definitely the food thing….
The Magellan astronomers were kind enough to let us utilize MagAO-X tonight while they took multi-object spectra with the LDSS3, so the team spent the night at the telescope taking response matrices, debugging code, and beginning some image processing.
I was finally able to get a nice consistent focus curve for camsci1 in the i-band!
I got frustrated with the focus code at one point and suggested that I may desire a career change to hedge fund manager, to which Joseph responded was a bad idea. So in honor of that exchange:
Today marks another historic and successful night of MagAO-X First Light…First Light Part 2! By the end of the long 24-hour day yesterday, we were all falling asleep in our chairs (except for Olivier who has mastered the art of staying awake). But thanks to Joseph’s heroic efforts, we were still able to produce a worthy blog post for first light of the instrument!
Today we have switched to a night schedule, so our “day” technically started at 6:30pm for dinner and ended at 6:30am for sunrise. But before I continue with MagAO-X Day 5: Second Light, I have some bonus pictures to contribute from yesterday!
Here is a nice model of what MagAO-X and the electronics rack should look like next to the telescope:
The instrument was designed to be placed 1 inch away from the Nasmyth port of the telescope, but we started with the instrument a couple feet away from the telescope to give us room for our alignment procedure.
To align MagAO-X to the telescope, we needed to insert a laser into our instrument that would shine out towards the telescope. The laser light would travel through the Nasmyth port, reflect off of the tertiary mirror, reflect off of the secondary mirror, and return back to us. If light comes back and hits our instrument, then that tells us we are aligned! If not, well, then we have some work to do.
Laird used some handy dandy binoculars to look into the telescope and get an idea of what we were dealing with.
Below is what Laird’s view looked like. It is quite confusing, but we can see the tertiary mirror with the primary mirror covers cracked open, and the secondary mirror as the small black circle hiding behind the image of the mirror covers cracked open.
Since we learned in elementary school that 2 points create a line, we needed to create an alignment target in the middle of the Nasmyth port to make sure that our laser beam goes through the center of the Nasmyth port. Then, we looked at the secondary mirror with binoculars to see if the laser was hitting the center of the mirror. Laird used an Italian trick learned by Armando (Laird and Jared’s old colleague from MagAO) to create an alignment target at the Nasmyth port. Laird mimicked the “Armando Pose” to commemorate this neat alignment technique.
Once the alignment target was setup, we inserted our alignment laser into the instrument. The key was to align the laser so that it was aligned to our instrument’s chief ray.
The panels were put back on and the laser shined through the entrance window.
Since we proved that our alignment method would work, we moved on to the final alignment, which involved bringing the instrument close to the Nasmyth port. We had a fancy alignment rod that helped us keep the instrument centered in X.
The instrument was moved into place and aligned! We measured the angle of the table with respect to the instrument for future reference using the laser tape.
Part of the clever MagAO-X design involves a floating optical table…the instrument actually floats on a thin layer of air! No one has done something like this for an astronomical instrument before. The idea is that floating will minimize the amount of vibrations in our instrument. We did a “float test” (turning on the air and watching the instrument) to make sure MagAO-X doesn’t hit the telescope. The air system calibrates itself when turned on, so the table rocks around like a boat until it finds its position. We had to make sure we gave enough room for MagAO-X to do its thing!
Finally, Laird removed the alignment laser from the instrument.
Jared and Kyle installed the tweeter cables.
And Jared caught in the moment of first light on MagAO-X!
MagAO-X Day 5: First LightPart 2
Now that I shared my bonus pictures from yesterday’s adventures, here is a quick summary of First Light Part 2! The day started out with a beautiful sunset and calming scenery.
Jared and Olivier worked on Olivier’s CACAO program to calibrate the 2K deformable mirror and optimize its performance. There were a lot of improvements from the previous night, and we saw our first on-sky Airy ring!
After a while of calibrations, we closed the loop and we saw our first Airy ring on sky! The left image is z’ band while the right is i band. The images look phenomenal!
These are big moments for the MagAO-X team and we are proud of what we have accomplished so far. It feels good to look back and see how far we’ve come.
Today (and tonight) is first light, the special time in every instrument project where you finally use it to look at astronomical targets instead of test light sources. This is also a twenty-four hour workday, with a full day of instrument preparation followed by a full night of observing and commissioning.
I suggested that Jared, as P.I., should write the blog. He suggested that, as the P.I., he was concerned with weightier things than blog posts. (Or, at least, that he should be.) Indeed, the MagAO/VisAO first light blog post was written by a graduate student.
I’m too tired to write good code, but I have mustered what’s left of my wits to bring you an account of MagAO-X’s first light night.
Last night, we held a meeting in the Aux (the auxiliary building that sits between Magellan Clay and Magellan Baade) where we planned a hilariously optimistic timetable for the day’s work. We’d be aligned to the telescope by lunchtime, have our electronics cabled shortly after, and use our copious free time to catch up on the software fixes and backlog of necessary functionality while we waited for sunset.
Needless to say, that did not happen on our schedule. It turns out that aligning an instrument that weighs a literal ton to a telescope is tricky. Laird, Alex, and Maggie sent a laser up to the secondary mirror and back to verify the alignment of the system, pivoting the entire optical table until the axes were aligned within … well, I don’t know the exact figure, but it’s not very many minutes of arc. Arcminutes are small, 1/60th of a degree each. (I tried to come up with a clever and easily-comprehended scale comparison, but I’ve been awake 24 hours and I leave this as an exercise for the reader.)
This (and other tasks) took us from morning until 10 PM, as these things tend to do.
Once the table was locked in position, we had to connect the delicate DM cables. You wouldn’t think “plugging something in” would be a 4 person job, but each connector gets a wipe down with two different solvents, ESD protection equipment is required, etc. etc. Jared, Kyle, Alex, and I did that. Miraculously, the DM came alive with zero stuck or otherwise non-responsive actuators an hour later! This could very well have been a three or four iteration process, so getting it in one go was great.
Afterwards, we had to make the dome “shipshape” (did you know Jared was in the Navy?) by clearing the platform of discarded zipties, cleanroom gowns, grad students, etc. We ended up opening up to clear skies at 12:30 AM. Our telescope operator, Mauricio, had been patiently waiting since before sunset for us to get our show on the road, and I think he was glad we made it. (It would have been a sad night of telescope time if we hadn’t!)
Next, we needed to get light down the pipe. Just because we’re fairly well aligned to the telescope doesn’t mean we know where a star will land on the detectors of a brand new instrument. Furthermore, we were offset a fair bit from the normal in-focus position, so a new offset had to be determined experimentally.
At 1:04 AM we had starlight on our acquisition cameras, and by 1:18 AM we had closed the AO loop on the “woofer” DM. Considering how many things have to work for this, getting it within 14 minutes on the very first try is practically unheard of. We had the MagAO-X / XWCL North team calling in via video chat to share in the experience.
While Jared, Olivier, and Kyle worked on boring stuff like making the AO loops correctly offload corrections to the telescope, I busied myself with far more important tasks in the MagAO-X Web GUI—like adding flames to the display that appear when the loop is closed.
I don’t wish to understate their accomplishment: they got us running in closed loop on our woofer, tweeter, tip-tilt mirror, and the telescope itself (via pointing and focus offsets).
I on the other hand… well, see for yourself.
With that essential functionality implemented, I took a break, along with Laird, Maggie, and Alex, to enjoy the Milky Way and southern sky. However, we were besieged by goats.
We were so excited by the actual moment of first light that we didn’t do the best job of documenting it for you, gentle readers. Maggie, the hippest member of the group, did capture it for her Snapchat story, however:
And I had the presence of mind to video the acquisition of our first star (but then neglected to video its appearance on the higher-resolution science-grade cameras):
When I came up to the control room at sunrise, I was surprised to find our telescope operator politely insisting to Jared that it was actually time to close the dome and stop working. (Well, not that surprised. Observers are always pushing their luck with the sun!)
This was the first of four nights of MagAO-X commissioning. I think we acquitted ourselves pretty well, all told. Fortunately, as you can see, our P.I. is no stranger to the adaptive optics game.
In accordance with MagAO-X 2019B Blog Rules, today’s song of the day is Counting Stars by OneRepublic. (A repeat, apparently, but not since 2015.)