PCBs: Progress and Compromise

Trace map of new LaserSETI power breakout board

Making our next 10 instruments efficiently, as well as ensuring their reliability and ease of maintenance, is a top priority. Some of you might remember a previous iteration of a power board, an attempt to reduce wiring and build effort that encompassed all power wiring in the instrument and attempted to eliminate a COTS (commercial off the shelf) component. That board, however, was overpriced and unnecessarily aggressive, so we switched vendors, changed how we did the cabling to avoid joints, and reduced the scope of the board to handling the two remaining wiring challenges: the fans and FLI cameras.

The result is above and below, and is 40x cheaper than before, while still eliminating all of the manual labor, difficulty when swapping out components, and long-term reliability risk! Fans plug into 4-pin headers, and FLI cables will screw into block terminals (not rendered below) in the bottom right. No soldering, everything labelled, quicker and better than could be done by hand.

3D rendering of new LaserSETI power breakout board

We hope you enjoy these peeks into the details behind LaserSETI, but stay tuned for some bigger updates and announcements soon!

Get Them While They’re Hot

Eclipses are one of those things that are easy to assume they’ve been around and will always be around. But no. While the Anthropic Principle guarantees the universe must be sufficiently fined tuned for us to exist, there’s nothing which requires us to be alive during the “Golden Age of Eclipses.”

So we’re just lucky. I like to think about what other wonders are there to be appreciated: nearby, on our planet, elsewhere in our universe. They must be uncountable.

Happy holidays to all and please enjoy as many wonders as you can!

New Set(s) of Wheels

Since we’re building 10 new instruments, we’ve made a number of small investments to make building them easier and faster. This was a fun one to share:

Two LaserSETI instrument bases, with different types of dollies to make building them easier

On the left, you’ll see an off-the-shelf appliance dolly. Cheap and easy to obtain, but it only allows access to the wiring area in the instrument base with the panels removed and with the dolly somewhat awkwardly interfering with said access. On the right, we’ve machined custom aluminum “legs” with casters, so the bottom panels can stay on and even be opened or closed as necessary. The machining took a couple of hours, however, so we’ll be testing both side-by-side, to see which fits the need better–or maybe both are good for slightly different purposes or phases of construction!

For reference on our development process, we’re including XKCD’s study of tool making below (“automation” in programming-speak). 😉

https://xkcd.com/1319

Enclosures mean Build Time!

Today’s the day when a lot of work streams come together in the Gantt chart: our 10 enclosures have been delivered. That means we can start building instruments, which means we can deploy them, which means more sky coverage and advancing the project!

6 palletes containing a metaphorical and literal ton of stainless steel

Darius from East Bay Machine Company was amazing. For hours, we lifted, unpacked, pushed, and repacked it all into our offsite storage unit. A forklift would’ve made it go at least 3 times faster,

Darius, Eliot, and their work cut out for them

We’ve been working towards this day for a long time and in a lot of ways. If you’ve been keeping up with us, you already know about the years’-worth of 3D printing to produce all the internal bracketry. The spreadsheet below shows we have all the parts we need for 6 complete instruments, but are closer to 70% done with overall printing. And you may remember we already purchased the cameras, transmission gratings, computers, and other critical components. Fundraising and observatory discussions have also been progressing.

Current 3D printing inventory management spreadsheet

Work always continues are a furious pace, so stay tuned to see how these Version 2.1 instruments shape up and test out, which new observatory we’re deploying to next, and more!

Racing for Life: K2-18b

[TL;DR: exciting astrobiology news at bottom]

One of the things that’s so great about the era of science that we’re living through, is the steady pace of amazing discoveries–almost to the point that they’re predictable. Exoplanets, the Higgs boson, the age of the universe, gravitational waves, and many others were foreseen and experienced regular progress until their ultimate discovery.

These areas of science are foundational to SETI, but I think the connection is deeper. Everything we’ve learned about the universe suggests the possibilities for abiogenesis elsewhere in the universe are endless. But simple life doesn’t build transmitters or starships. And, as essentially a brand new technological civilization on the timescale of our star, galaxy, or universe, our ability to predict how and how often other civilizations might evolve could not be more limited. We have no exobiology, exospychology, or exosociology–only physics and chemistry which are universal by definition.

Hopefully that explains why I’ve said for a while now that I view the search for technosignatures as in a race with astrobiology. I picture it like the children’s story of the race between the tortoise and the hare. Astrobiology is the tortoise, making regular progress but always painful to wait for the next instrument or discovery. It’s not actually slow, it’s really amazingly fast that we get to watch a fascinating science unfold in real-time, but it’s hard to wait for things you’re excited about! SETI, of course, is the hare, the rabbit that makes rapid spurts of progress. Who knows when and how a signal might be found and, reliant on unpredictable private funding, technosignature projects–like LaserSETI!–show up irregularly and take as big a bite out of the problem as they can.

And so that’s the background which makes NASA’s announcement of observations of “habitable zone” exoplanet K2-18b an exciting step for the astrobiology tortoise. Using a technique called transit spectroscopy (see Update at bottom of post), which measures starlight passing through the planet’s atmosphere while it’s between us and its host star, they’ve identified a chemical composition that indicates it’s potentially a water world. And, especially tantalizing, there’s also hints of dimethyl sulfide (DMS) which, on Earth, is only produced by biology. It’s “the most abundant biological sulfur compound emitted to the atmosphere” and so makes a credible candidate for the first biosignature gas we might detect.

Spectrum of Exoplanet K2-18b’s atmosphere, showing molecular composition (credit: NASA et al)

Stay tuned because it’s too early to say if this DMS is a real or just a trick of the noise in the limited data they’ve been able to collect thus far. After all, we can point the telescope wherever we want, but we can’t make the “K2-18 year” to happen any faster to produce more transits!

Would I be disappointed if astrobiology beat SETI to discovering other life in the universe? Absolutely not! The most interesting scientific discovery of my lifetime will be amazing whoever makes it, and it will only hasten the search for technosignatures and answering the other half of the question, “are we alone?”

Update: Here’s a great illustration of transit spectroscopy:

Maintenance Week

We didn’t get as much time on the sky this week than normal, as we had work going on at both observatories, RFO and IfA. One was planned, the other not so much.

At IfA, our maintenance was unplanned. IFA2’s sunshade stopped working, which is scary because the sunshade protects from the Sun potentially damaging the shutter on the FLI science cameras. You can see the problem below, using our internal “PiCam”: the polycarbonate gear started to slip around the motor shaft.

We recent started a project to detect the the sunshade position using computer vision to catch exactly this sort of problem automatically but, since we currently check every morning, we caught it manually. Fortunately, Team LaserSETI member Doug Hagan who’s local on Maui, was able to make the long drive up Haleakala and close it by hand.

Speaking of cameras, the horz-cam on IFA1 had started misbehaving transiently. We tried remote diagnostics and troubleshooting but eventually we had to admit it wasn’t succeeding. So we’ve sent a new camera (and a new gear) to Doug, and he’ll be replacing both shortly.

Meanwhile, at RFO in California, they’re upgrading the roof surface of the observatory which our instruments sit directly on top of. We worked with observatory team to come up with a plan for them to coat the the whole roof without disturbing the position of the instruments.

IfA Maui Back Online

If you’ve been reading the news recently, it won’t surprise you to hear that our instruments on the summit of Haleakala, Maui, have been offline for the past couple days.

The good news is they came back online this afternoon, and seem to be in great shape. In fact, I would assess-timate the high winds even did a good job cleaning the windows.

View through IFA2's "pi camera"
What LaserSETI’s IFA2 instrument saw when it woke up

Of course, that’s the easy part of this post. Our knowledge of the enormity of the tragedy from the fires on Maui grows day over day, and wrenches our hearts ever harder. People, businesses, history, nature, all gone and without warning.

Personally, I haven’t heard from everyone I know there, but each one I do hear from is a gift. It reminds me all too much of the firestorms that struck California in recent years–not “just” a fire, but a fast-moving “natural” blowtorch that creates its own weather as it decimates everything in its path. I keep thinking about a sign that hangs in my mother-in-law’s house, and she was kind enough to take a picture of it for me.

If there’s anything you can do to help the wonderful people of Maui recover, now or in the future, I hope you’ll act on that opportunity. The best resource I could find on ways to help was here.

All the life we know of clings to the thin skin of a giant rock flying through space. I think we should take care of each other.

Maintaining Trouble

The hard drive in RFO2 has given us trouble before. A year ago, we swapped out the disk, the enclosure, and even the computer itself. For a while, it was smooth sailing, but then started acting up again.

So, after replacing the disk and enclosure again, we tried the power and data cables. That was an improvement, but still not 100%. And since we can’t observe without the hard drive, anything less than perfect isn’t good enough.

We’ll be headed up to Ferguson again soon, this time with a new idea in hand, to try to put this trouble maker to bed once and for all: a solid state disk. Smaller capacity, but completely different performance, electrical, and other characteristics.

Since RFO2 wants to be an attention-hogging snowflake, here’s the work from its perspective. LaserSITTIE is, by far, my favorite piece of maintenance equipment. There’s nothing like sitting when we previously had to bend over the instrument, or kneeling on it instead of the often-sweltering roof.

High-tech problems? Go low!

Many of LaserSETI’s parts are challenging to print, simply due to the required function of the part and the limitations of Fused Deposition Manufacturing (FDM), aka 3D printing. We’d worked out most of the kinks in the original design of the parts, but one has been giving us trouble.

Failed print used to fabricate new brace which is holding broken column in place

This is the bracket that holds the “horz-cam” but also, underneath in the bay visible above, holds the router that connects all the various computers that make LaserSETI operate and analyze.

The near side is where all the ethernet cables plug in, so obviously can’t be a solid wall. The highlighted support pillar is large enough to grow into the camera bracket higher up, but small enough to not cause a problem with the cables below. But sometimes, if everything below didn’t print 1000% perfectly, it became a long lever arm that got pushed around by the print head and eventually broke off.

It’s a large part, taking 75 hours of machine time and about $15 in raw plastic. So a print failure more than halfway through is a frustrating waste of time, money, and effort. And it’d happened one time too many times. There are a plethora of factors, mainly the printer and type of thermoplastic, but many variables aren’t realistic to control precisely, such condition of the machine, ambient temperature and humidity, feedstock humidity and other imperfections.

We’d tried fixing it “the right way” by printing a support pillar on the side, meant to be broken off once the print job finishes. But it wasn’t getting a solid enough connection to the model and too often failed in its one job.

Printing again with the brace in place

As the saying goes, “if you want something done right, do it yourself.” So we carefully crafted a brace from scrap wood, it fits tightly, and we’re expecting this will get the job success rate up, from maybe 65% to more like 100%!