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Comment Re:Groundbreaking was awesome (Score 1) 98

That's a brilliant piece of similar-triangles analysis, but it begs a couple of questions.

It assumes an airplane directly approaching the telescope at a distance of 1.6km. Otherwise, those "huge headlights" wouldn't be pointing at you, and the plane would be through your visual field in a small fraction of a second. How often will this happen?

It assumes a telescope directly pointing at the approaching airplane. How often will you be observing something low enough to the horizon to make this possible, never mind in the precise direction from which the airplane is approaching?

Please, though, go ahead and provide some references to vision hazards associated with pointing large telescopes at anything other than the Sun or a laser emitter. I haven't come across any in the past, I didn't turn up any with a couple of quick Google searches, and I don't think you'll find any professional or advanced amateur astronomers who agree with you.

Comment Re:Groundbreaking was awesome (Score 3, Informative) 98

No. No, they won't.

Think about the distance to an airplane in flight. Next, think about the area of the sphere with that radius, and how little of that area even a giant telescope's mirror will intercept. You're not going to be blinded. You might be surprised, and you might lose your dark adaptation, but you're not going to be blinded.

Now, think about the area subtended by the telescope's field of view -- in the example above, a circle perhaps one minute of arc in diameter. What are the odds that a bright meteor will pass through that area during an observing session, slowly enough to linger long enough to cause damage? Pretty darn tiny. (Your odds may actually be worse if you aren't using the telescope, because then you're more vulnerable to a really bright meteor crossing your wide native field of view.)

The "real reason" eyepieces are rarely fitted to huge telescopes is because it's wasteful. The human eye is much less sensitive than the instruments normally fitted to such a telescope, and it doesn't record its perceptions for later analysis. Demand for real scientific observations from a large telescope always exceeds available time, so nobody wants to waste the machine's capability for some momentary sensual gratification.

As for safety, until planes are outfitted with multi-watt lasers specifically targeting telescope facilities, or until we're ambushed by a dense swarm of very bright meteors again targeting telescopes (so their apparent motion is slow enough to make them linger in a tiny field of view), our visual observers are pretty darn safe.

Besides, you only look through the eyepiece with one eye at a time, so you'll have a spare...

Comment Re:One possible argument for lunar industrializati (Score 1) 98

As careysub already posted with a different link, no, it doesn't. In fact, it appears to rise up and coat things that are left on the lunar surface, darkening them.

One of the source articles for the Wikipedia entry above talks about this in more detail, but also points out that lunar soil appears to sinter really, really easily when microwaved. It seems like this could be an effective and (via plentiful electricity from sunlight) economical way to "dust-proof" limited regions of the lunar surface. That, coupled with a fairly simple static-charged chicken-wire fence to divert or intercept laterally-propelled dust, might well make the problem manageable.

Comment Re:Groundbreaking was awesome (Score 1) 98

That's... amazing. Color me incredibly jealous.

I'd guess they were throwing away nearly all that aperture -- to get all the scope's light through a 4mm exit pupil, you'd need close to 2000x magnification, which would make the nebula look like it was about 24 degrees across -- okay, that would fit perfectly into a normal field of view.

So, yeah. I hate you even more.

(Wonder what kind of 4mm lens could successfully catch all the light from a system that size? It's been a long, long time since I was immersed in the amateur-telescope-maker literature...)

Comment One possible argument for lunar industrialization (Score 3, Insightful) 98

It seems like the Moon's surface could be a fantastic place for an absurdly large optical telescope. No significant atmosphere, little or no vibration, low gravity (making for less distortion of the optics), and plentiful raw materials for making fused silica and aluminum surfaces.

Obvious drawbacks: not a good place for humans, a two-week period of daylight (not necessarily a deal-breaker without an atmosphere, but a source of thermal stress), and a REALLY BIG dust problem.

Comment Re:Vaporware and a guess about the secret. (Score 1) 51

You want stereo vision but you also need the focal plane to change as the eye changes focus.

Fortunately, there's a cheap and easy solution to this: age. By the time you're 50, it's extremely unlikely that you'll have enough focal accommodation to matter.

This means I'd be totally ready for VR, if not for my extreme susceptibility to lag-induced motion sickness.

Comment Re:Trend towards illegibility (Score 4, Informative) 146

My kingdom for mod points.

Seriously, everybody go look at this website, now linkified for your convenience.

It's concise; it won't take much of your time. And if you're too cool to cope with high-contrast text, well, feel free to smear some Vaseline on your horn-rimmed glasses before following the link.

Comment Probably a result of dev/designer demographics... (Score 4, Insightful) 146

I think we all see that there's a big push toward The New Shiny for implementing Web UIs, and a push toward hiring young frontier-chasers in place of older developers and designers who are perhaps more attached to older, less cutting-edge technologies.

Well, surprise -- younger people IN GENERAL have an easier time focusing on close targets, perceiving low-contrast images, and dealing with generally lower light levels.

Now, most of the designers I've worked with at least pay lip service to accessibility, universal design, and maybe even special-needs users. But when they're showing mockups to decision-makers, they still seem to push for what's trendy -- and, hey, the twenty- and thirty-somethings in the room have no trouble reading it, and if the forty- and fifty-somethings do, they sure aren't going to call further attention to their "differently youthful" status by complaining about it.

As a result, we see today's visual design. If we squint enough.

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