dakr

7 ms·

31.
by dakr 2y ago
As I recall from school, your lead suit would need to be more than 3 lightyears thick to make the chance of a neutrino (that was already heading towards you) going through you fall to 50%.
32.
by dakr 2y ago
The Rayleigh criterion gives a limiting resolution assuming monochromatic light. The quoted 16 mas is a demonstrated resolution for a broadband filter. So, I was ballparking things and they have achieved an awesome result for a relatively s
33.
by dakr 2y ago
Presumably you meant to say 14 miles, not 14 feet. Also, since the adaptive optic system acts on the near-IR light, let's shift the 500nm used to calculate the Rayleigh criterion to at least 1 micron, which doubles the limiting resolut
34.
by dakr 2y ago
The issue is rotation of the sky about the line of sight axis. Whether the exposures are short or long, over time the sky will rotate more than what an in-camera system can compensate for (the amount of rotation depends on location/tim
35.
by dakr 3y ago
I was also wondering about the stellar wind stripping away the atmosphere. Planets close enough to their stars to be tidally locked will experience more stellar wind than those farther away and dwarf stars have more flare events than stars
36.
by dakr 3y ago
The world is interconnected, especially science. Just sticking with medical imaging, a lot of work done in astronomy has crossed over and had direct impact on medicine. CT scans are one example (algorithms and code from astronomy), and if y
37.
by dakr 3y ago
Haha, it must be inflation. Back when I was involved the 1TB number was the one being thrown around. Thanks for posting that link. IPAC is really doing well for themselves with all the new projects they're hosting.
38.
by dakr 3y ago
Back when 10TB was enough space for the entire Sloan survey, Vera Rubin Observatory was expected to produce 1TB every night. They dug a trench up into the mountains to lay a fiber optic cable specifically (and only) for Vera Rubin.
39.
by dakr 3y ago
It's not really about one being better than the other, just that they're designed for different purposes. Euclid is a survey telescope built to research dark matter, for which it has a large field of view so that it can build up a
40.
by dakr 3y ago
Just a quick note to say that JWST is not the first telescope to give us these kinds of views! There are numerous others, SOFIA, IRAS, IRTF, and Alma to name a just a few.
41.
by dakr 3y ago
The encyclopedic CRC handbook used to (maybe still does?) list what different metals, minerals, and other materials taste like. It seems a lot of people felt taste was an important sense to make use of.
42.
by dakr 3y ago
I take this progression to mean that the novice will design a part or subsystem that is good by itself. The more experienced engineer is thinking bigger by taking into account the effect of the larger design on the portion they are working
43.
by dakr 4y ago
I remember my jaw dropping while sitting in a colloquium hearing about astrometry.net from David Hogg back in ...2007? Fast forwarding a few years, we started using it at SOFIA Observatory to help speed up telescope acquisitions.
44.
by dakr 4y ago
Well, you can do it with an 8m-diameter primary mirror, because it's been done at Gemini Observatory. Keck and the VLT have directly imaged exoplanets as well. See this list: https://en.wikipedia.org/wiki/List_of_d
45.
by dakr 4y ago
I had a summer internship where I got bored and read wikipedia a lot. Reading about engines and transmissions there helped me a lot when I learned to drive stick. Being able to visualize what was mechanically happening gave me a little bit
46.
by dakr 4y ago
There's a 300 degree club at the south pole. Strip, jump in 200 degF water, then run outside around the building where it's -100 degF.
47.
by dakr 4y ago
The fact that it's hard to know the inputs accurately and precisely doesn't make this any less of an equation. Given some inputs on one side, you get an output on the other. You might as well call y = mx + b an estimate.
48.
by dakr 4y ago
Focusing on getting good detectors and optics in a great observing site is a more efficient use of resources than organizing, collecting, calibrating, troubleshooting, etc. a crowdsourced effort. Plus, I imagine the CMOS detectors they&#x27
49.
by dakr 4y ago
In some kinds of fishing, it seems they deploy nets and then collect them later, so this would help them not lose it in the first place. Also, location information is always good to have and is useful for more than just finding lost stuff.
50.
by dakr 4y ago
Not to minimize the impact to ocean life and the environment, but lost fishing gear costs money. The upside of which is that there is direct financial incentive to recover lost gear. I know nothing about this space, but a former coworker st
51.
by dakr 4y ago
From the article: "Unlike other forms of marine debris, fishing gear is specifically designed to catch marine life. Under certain conditions, derelict gear can continue to catch and kill organisms for years."
52.
by dakr 4y ago
I use a syringe to refill cartridges from whatever bottle of ink I want to use. The cartridges can be reused many many times. edit: lol, if I had reloaded the page before commenting, I would have seen all of these people saying the same thi
53.
by dakr 5y ago
Your phone may not be moving, but the satellites are. The obstruction is not static in that case.
54.
by dakr 5y ago
For $117 million they could have hired administrators at each school to field phone calls from parents and take care of records.
55.
by dakr 5y ago
You're being naive, and haven't demonstrated that you know anything about astronomy, or optics in general, really. Astronomers are very cost-conscious, which is exactly why the decadal survey exists - to direct limited funding to
56.
by dakr 5y ago
This real hardware handles quaternions just fine: https://en.wikipedia.org/wiki/Stratospheric_Observatory_for_...
57.
by dakr 6y ago
From reading the article it seems likes they're using the fact that photons are Poisson distributed. Just like raindrops or particles emitted by radioactive decay, you can determine an average rate of flux and the probability distribut
58.
by dakr 8y ago
An aside, but when it comes to electronic beam-steering, it's hard not to talk about LOFAR[1], a low-frequency radio interferometer for astronomy spread across Europe. [1] https://en.wikipedia.org/wiki/LOFAR
59.
by dakr 10y ago
Physics Today had a nice article on sailing a few years back. I think it's well done: The physics of sailing - http://physicstoday.scitation.org/doi/full/10.1063/1.2883908
60.
by dakr 10y ago
Saying that an investment strategy has averaged positive returns over 40+ years may be true, but is not necessarily useful information. Over very long periods of time, there are many strategies that will provide an average positive return.

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