Tonight marks the end of our time on sky for the 2022B run. Though we have had a bit of a rough week of seeing, humidity, etc., tonight we scored some decent conditions and got to do some of the science we’ve all been eager to do.
Eden and Alycia got to visit the 100″ down the hill from the Magellans this afternoon. I would have gone with them but had a final to study for!
Jared also made friends with a LCO resident.
And Carla has returned with more astronomer snacks!
We forgot to take a group photo at the beginning of the night, and failed to all be located in the same place at once this morning – so we will take a victory photo for you viewers in the near future.
There is a peculiar thing about the way the Universe is constructed: it is nearly, but not completely, impossible for one civilization to detect another civilization (unless they want to be found). That parenthetical caveat is worth explaining up front: essentially all SETI conducted to date is predicated on active, intentional attempts to communicate. There are important and interesting exceptions (like G-Hat, see https://www.centauri-dreams.org/2015/04/16/g-hat-searching-for-kardashev-type-iii/ for an explainer). Since I’m going there, let’s also just deal with the Fermi Paradox: it’s not a thing. It has an entering implicit assumption that there is a statistically significant null result that needs to be explained. There isn’t. To understand this, try to answer the question: “how many derelict Imperial-class Star Destroyers are currently floating around in our Solar System?”. You can use this authoritative reference: and this figure:
So with all that out of the way, one probably wants to ask: so how would you go about detecting another civilization mister doctor snooty astrophysics dude? The answer is OF COURSE direct imaging with wavefront control equipped large to giant telescopes feeding coronagraphs. But this is where (I think that) it gets a little weird. It’s kinda like the Universe was put together with a set of laws and rules that make it hard to image someone else’s backyard. And, to be fair, this isn’t just a problem for direct imaging. The main fundamental thing that makes it hard to do direct imaging of Earth-like planets is also the thing that makes passive-SETI-for-leakage not a thing: and it’s photon noise.
(Despite appearances, this is an entertainment blog, so this is all hand-wavy-ness intended for Emotional Appeal, plus it’s day whatever it is since I left home and we’re in 2 arcsecond seeing and the TCS is broken and so I’m not that interested. So I’m not going to actually do math or anything. But I can, so don’t try me.)
If you try to measure the brightness of a source that sends you 1 photon at a time, the noise or uncertainty of your measurement of said source’s brightness will be 1. We call this is a signal-to-noise ratio of 1. If the source sends you 9 photons, then the noise is 3, so SNR=3. The noise is always the square root. The main point here is that this is a fundamental property of photons. Now we have to consider the size and brightness of stars and their distribution in space and time. We could go down a deep rabbit hole here, but the bottom line is that stars aren’t bright enough or close enough to give us enough photons to do the wavefront control we need. That square-root thing is the kinda weird (or weird for the purposes of this post) part: it’s just right to make it barely possible, but really f-ing hard.
If you are extremely naive and don’t pay attention to temporal power spectra and closed-loop transfer functions, you come up with answers like “we need picometer precision to achieve the 10 billion contrast ratio to detect an Earth twin”. For reference, a picometer is factors of 100 smaller than the atoms (Aluminum, Silver, Gold) that we coat our mirrors with. My collaboratorsandI know better, but the point is that it is still f-ing hard. And the barriers once again seem to be coming from fundamental properties of the Universe (here we’re not just dealing with electroweak, but strong force weirdness too).
Not to mention atmospheric turbulence. WTAF is up with that?
This is my grand conspiracy theory: the point to all of these rules is to prevent us from finding out about each other until we get our civilizational shit together. It’s like photon noise and the distribution of baryons are playpen walls. You can’t climb out until you’re ready. You have to be able build the telescopes, and focus the resources on the optics and mechanics and signal processing and control theory to achieve the needed measurement precision. You have to be able to build 25 meter ground based telescopes, and 6.5 meter space telescopes, and you have to solve the horrific challenge posed by bureacracy while you’re at it.
But now I’m going to drive this blog post off the rails. I actually wonder, sometimes, in the middle of the night (or trucking strikes and pandemics) if the Universe is actually a dirty ref. Do you ever get the feeling that there’s always something? Some examples: the pandemic seemed perfectly timed to kill our momentum; just when we are getting going again, the trucking strike costs us a bunch of time and money; our inspiration project SCExAO is currently losing time due to a (another) volcanic eruption. Etc. My self-centered delusions of galactic-scale importance draw some inspiration from this under-appreciated piece of Charlie Sheen magic:
Look, I’m not saying it’s aliens. But it just might be aliens. At the very least, we have a long ways to go in terms of perfecting the Kung-Fu we practice to the point where we can start searching extrasolar worlds for life. I really do believe that we (MagAO-X, SCExAO, XWCL, UASAL) as a team can pull this off, and are doing things the right way with the right engineering and project management approaches, and of course some awesome amazing-team dynamics. But will the Universe let us?
As they say, Like-Follow-Subscribe and maybe you’ll find out. But if I’m right we have many more adventures ahead of us.
Today’s song of the day poses a question: is it a Daughtry cover if he never sings?
I’m baaaaaack. My last post on April 23 promised that if I got to come in person, I’d bring goodies. I tried to make good, but bad weather makes for a lot of snacking need.
The daytime weather has been lovely, for the viscachas and humans who happen to be awake then. After a couple hours of data taking, the dome started dripping tonight. Maybe our Vizzy friends are taking showers under it.
In case you were wondering, KLIP is an algorithm we use for reducing our MagAO-X data, so we’d rather be KLIPping than Dripping.
I got a taste of sunshine today when I got up early to get my get-out-of-bubble Covid test (negative, yay!) and then treated myself to a cheese empanada by going to lunch. Eden has provided this view of our dome’s “empanada empire.”
Is it really possible that no one has used Train’s “Drops of Jupiter” as song of the day before? Drops of starlight are, alas, falling on the ground and not the mirrors tonight as drops of water fall from the dome.
So the last two nights have followed the same pattern: decent seeing and good images until about midnight-1am, then seeing creeps up and up and up and blows past the top of the chart, and we all slump around the control room and lounge in a funk. But tonight there is an added bonus of a storm rolling in!
As I write this here is the current weather conditions:
Education break: “seeing” is how astronomers quantify how sharp or blurry a star image is. Basically if the seeing is 1 arcsecond, then a star’s image will span about 1 arcsecond on the sky. So a large seeing value means more smeared out images. MagAO-X really needs low seeing to function well – 1 arcsecond is difficult for us to work in. 2 arcseconds is unheard of!! Until the last few nights that is.
The best data we’ve gotten the last few days is VIZZIES!!!!!
BABY VIZZIES by Eden
VIZZIE SNACK TIME by me
More pics from today
You know your greed for empanadas is not one of your better qualities
Tomorrow is empanada Sunday after all
You know what they say. Dry hands at night astronomer’s delight.
Tonight started of quite well. We finally had average conditions, which much better than the 2 arcseconds seeing from before! The first target of the night is one from Logan. She is searching for white dwarf companions around main sequence stars. Stellar evolution tells us that there should be more white dwarfs than we can see. These white dwarfs could be hidden as companions close by brighter stars, which make it difficult to see them. MagAO-X is an ideal instrument to search for faint things next to bright things. We use coronagraphs to block the starlight of the primary to search for faint companions. Below is a video showing MagAO-X running at full steam trying to get maximum performance.
Sadly, we had to stop again around midnight. The seeing went through the roof.
The seeing became so bad that we just gave up trying to get science data and we switched to sparkle engineering. This also allowed us to explore the more important things in life. Such as tasting all the different types of milk that LCO has to offer. The reviews and commentary are outside the scope of this blog post and will be part of later work.
At the end of the night the seeing became a bit better and Logan could take over again to search for her white dwarf companions. Somehow it looked like all stars we looked at were binary stars. After seeing 5 binary systems we realized that it was the system itself that created the binary components!
And during the lows of the night we also lost our dear friend Vizzy. As if the night had not been bad enough.
After the night ended I continued to work on some daytime engineering to get the new integrated coronagraph/wavefront sensor to work. This has been manufactured by the local manufacturista Avalon McLeod. Yesterday night we commissioned the coronagraph part of this optic. And today we did the lab tests of the wavefront sensor side. Now we only need to get the wavefront sensor on sky!
The last week has been though weather wise. So here we are hoping for better skies in the next couple of nights.