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Comment Re:Missing option: CNC Router (Score 1) 175

The PLA that I use in my old Ultimaker is melted in the printer at 220C, but it becomes soft and deforms at the much lower 60C that we typically get in our cars in Tucson in the summer. I had to print a second set of propeller blades for my nephew's underwater robot after he left it in his car one day!

Comment Re:Meh. (Score 1) 175

I have one at home that I use for doing iterative prototypes of product designs, among other things. When the turnaround time for improving a design is an hour, it's possible to make a lot of refinements.

Comment Re:I have some questions (Score 2) 129

I work on the engineering side, rather than the project management side. The two EHT telescopes that I work on are in Arizona, although I build some of the hardware that's being taken to the South Pole Telescope. It's getting improved to be a part of the EHT. One of the Arizona telescopes is a prototpye ALMA antenna that we just moved here from New Mexico last year, and got working a month ago.

Observations are typically done in March/April. This gives good weather at the many sites involved. The typical run is a week, and they try to get several 10-minute recordings during that time period. The data is recorded at 1 Gbyte/sec onto banks of hard drives, then shipped by FedEx to MIT for correlation. (I don't know if a FedEx truck makes it to the South Pole every day.)

The frequency used for most observations in in the 1.3mm band. The baselines are intercontinental (Arizona, Hawaii, Chile, hopefully Antarctica), up to 5000 miles. The goal is to actually get fringes between all stations, although that's not always possible due to weather and/or equipment acting up.

Comment Re:hang on (Score 1) 334

I work in radio astronomy. From what I can gather, things in other star systems are too far away to even be able to communicate, much less transport between them.

Those huge arrays of radio telescopes being built in Chile and South Africa are able to detect things on the order of a planet in size. That doesn't mean that they can communicate with the planet, just see that it exists.

Comment Re:Power does not fail here (Score 2) 236

I live in the Arizona desert, where we have violent summer thunderstorms, and lots of overhead wires for power and telephone. We sometimes have the wind knock over long stretches of lines. It's worse on the mountaintops where the telescope I work on are located. Each site has a generator to keep the equipment running.

Comment Re:There are two problems here... (Score 1) 137

I am a staff engineer at a university, so I receive most all the spam that is sent to the university's professors. I get many invitations to conferences. I assume that most, if not all, of them are bogus, since I'm not a researcher and most of them are for fields that I don't work in.

When I have looked into one or two of them out of curiosity, I went down a rabbit hole of internet weirdness (SEO, lack of citations, etc.)

Comment Re:Reality check on resolution (Score 1) 91

This is achieved by having a really big aperture. In this case, the array is spread out over 15 km, so the aperture is effectively that size. Try putting a 15 km array of telescopes in space! The information processing is necessary to combine the signals, as a 15 km single-dish antenna would be a bit tricky to set up.

One number that's woefully missing from the news stories is the wavelength (frequency) at which the observation was made. NRAO has made two sets of receivers, at 3 mm and 1.3 mm wavelengths, for this array. Other countries have made different receivers, but I don't know if any of those are being used right now. Ned more information!

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