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Amazingly, the latest publicised attack is apparently spread though the clicking-on-a-dodgy-link-in-an-email mechanism. (Once inside a network, it then spreads itself, but that's apparently how it first gets in.) ... and, up-to-date patched machines would not have been vulnerable. So there's good advice in the OP on making sure backups exist, but there's also some basic education and procedures that need to be attended to.

Large fonts are proof of something.

Please see: https://en.wikipedia.org/wiki/RNA_world

Bit of a side point, really, but laser light also spreads more than many expect. e.g. firing a laser at the Moon to determine distance, the laser beam is 6.5 km wide by the time it reaches the Moon. https://en.wikipedia.org/wiki/Lunar_Laser_Ranging_experiment So at any distance, little of the laser light is going to hit the target probe. (Also, there'd be few choices in direction.)

First done in 1959. https://en.wikipedia.org/wiki/Luna_3 58 years ago.

Seven.

That's the thing, it's relative. From the point of view of A and C, B contracts. It's not just some visual illusion. But according to B, they're their normal length - no change to their stress etc. (According to B it's A and C that contract). The Universe is weird. https://en.wikipedia.org/wiki/Length_contraction http://www.rafimoor.com/english/SRE.htm#Length%20Contraction

B Maybe take a step back, and explain what YOU think length contraction is.

It wouldn't make sense for length contraction to work the way you expect, because it's relative. Say A considers B moving at speed X. And C considers B moving at speed Y (different to X). First up: B does not consider their own view of space as contracted (e.g. if their own spaceship was 50 m long before launch, they still think it's 50 m long). Secondly: as X and Y are different, A and C will have different views of the contraction of B.

Was that Pink Floyd?

If I were to guess, I'd think he's trying to make a point about the "balloon analogy" for aspects of expansion of the Universe. (And missing the point that it's an analogy intended to illustrate aspects.)

That light is slowed in a medium isn't speculation: https://en.wikipedia.org/wiki/Speed_of_light#In_a_medium As for the "Hmmmmmmm?": https://en.wikipedia.org/wiki/Argument_from_ignorance#Argument_from_incredulity.2FLack_of_imagination

Why do you always put an apostrophe in the word "does"?

As soon as you bring rockets into it, you're really talking about something quite different to the apparent motion of galaxies due to expansion. Please stop mixing your metaphors; please be more precise.

You sneaky sneaky thing, you! Don't you remember:

Mass is one of the factors in terminal velocity. So the weighted ball will get faster than the unweighted ball. (Been trying to find a good worked example. For a start: https://en.wikipedia.org/wiki/Terminal_velocity#Derivation_for_terminal_velocity )

Not when dropped in air. Air causes drag. Drag is a force. The different masses of the pin pong ball and ping pong ball full of water then makes a difference. ( Extreme example: a parachutist vs a parachutist whose chute didn't open - same mass, different rate of fall. Of course, the two ping pong balls have the same shape, but ... ) https://www.quora.com/If-we-drop-different-weights-from-same-height-which-will-fall-first-to-ground

( ...and on the Moon: )

You keep saying that.

No. If expansion gave actual-moving-through-space-speed, the furthest galaxies wouldn't be receding faster than light, as we know velocities don't add that way. Metric expansion of space is different.

Just to illustrate metric expansion. Say these letters are galaxies and the hyphens are the space between them: A-B-C-D-E-F-G-H-I-J-K-L-M Note that M is 12 x "-" away from A. After some time, space has expanded: A---B---C---D---E---F---G---H---I---J---K---L---M Now, M is 36 x "-" away from A. That seems a lot: | . . . . . . | A-B-C-D-E-F-G-H-I-J-K-L-M | A---B---C---D---E---F---G---H---I---J---K---L---M ... from the point of view of A, M is now (apparently) "moving" very fast (it moves 18 hyphens in one unit of time). But perspective, or point of view, is still relevant here. Take the view from L: |.| A-B-C-D-E-F-G-H-I-J-K-L-M | A---B---C---D---E---F---G---H---I---J---K---L---M ... not such a big deal, according to L, M moves 2 hyphens in one unit of time; that's a lot less than 18 ... there's no point being incredulous about that (apparent) "speed" of 18 from the point of view of A. As to why/how the Universe is expanding, that's a topic that deserves its own thread.

Multiple experiments that give results that match expectation, yet are waved away by claims of somehow all having the same "error" (that yet gives that expected result). It's clear who is operating on belief, instead of science.

May be a good time for this: "What is the experimental basis of Special Relativity?" http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.html (Hope I'm not repeating earlier use.)

By that reasoning you may as well call astrology and homeopathy "scientific". Or in other words, why subvert a thread by trying to redefine the topic?

Yeah, it all comes down to the funding.