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The retro-styled Ford Bronco is more than just fun to look at. It’s also a blast to drive no matter the weather. It offers praiseworthy capability and character in equal measure, and its rugged design looks cool without trying too hard. The Bronco also has more on-road appeal than the rival Jeep Wrangler thanks to its smoother ride quality and more stable handling.

Whether you prefer a sports car, sedan, truck or SUV, there’s something fun to drive during the winter months. Whatever your choice, we recommend swapping your vehicle’s all-season or performance tires for a proper set of winter tires to provide extra grip in snowy or icy conditions.

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Doing a quick back-of-the-envelope calculation, I'd guess the primary mirror in such a design would be somewhere around 100 tons.

1. You could argue that it really "culminated" in the BTA-6. This is a 6 meter telescope located in Russia. Although its designers (apparently) believed they could successfully fabricate a mirror this size, its mirror cracked after a fairly short time, and had to be replaced. Although larger than the Hale telescope and therefore theoretically more sensitive and capable of higher resolution, its contributions have been comparatively minimal. In any case, its mirror design is enough like the Hale's that it doesn't change the overall situation to any significant degree.

On your second question: a back surface reflective coating implies an additional reflective surface: the air-glass interface. This leads to increased light losses and the need for anti-reflective coatings.

Of all the pickup trucks on sale in 2024, Edmunds chose the Chevy Colorado as its Edmunds Top Rated Truck of the year. It raises the bar for midsize trucks, and the Trail Boss version exemplifies why.

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Look at the slopes of the lines from $400\ \mathrm{nm}$ to $700\ \mathrm{nm}$ - silver varies from $80\%$ to $95\%$ reflectance, while aluminum stays between $90\%$ and $93\%$. So yes, a primarily red image will be slightly dimmer in aluminum than in silver, but all images are slightly reddened (the blues are suppressed more heavily than the reds) in silver, whereas aluminum gives a more faithful representation of the colors. (Plus primarily blue images will actually be darker in a silver mirror than an aluminum mirror.) For everyday use, it's easy to compensate for a darker image (just light up the room more), but not so easy to compensate for an image that has the wrong colors.

The "wave" of telescopes that (sort of1) culminated in the Hale 200-inch at Mount Palomar was based (in large part) on the invention of Pyrex. Earlier glass was enough weaker that it required a considerably thicker mirror and/or better support structure so the center didn't "sag" under its own weight. The Hale's 200-inch mirror uses a honeycomb design to reduce its mass (to around 14.5 tons), and still requires a fairly elaborate structure to support it without distorting the mirror.

The Trail Boss is decently equipped with features, though heated front seats are curiously unavailable. You can add heated side mirrors and all-season floor mats as options.

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If anything, actual development has tended to go the opposite direction: if I'm not mistaken, the "Zerodur" ceramic used in the mirrors for the Keck telescopes is nearly (fully?) opaque. Although it's roughly double the diameter (and therefore quadruple the area) the primary mirror in each of the Keck telescopes totals only about 18 tons (but note the "totals"--each mirror is actually built of 36 segments, each of which is around half a ton).

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Equipped with all-terrain tires, an off-road suspension with a 2-inch lift from the factory, and an automatic four-wheel-drive system, the Colorado Trail Boss is a five-passenger crew-cab pickup ready for almost anything. Its turbocharged 2.7-liter four-cylinder engine provides 310 horsepower and 430 lb-ft of torque is plenty for powering through snow drifts or towing up to 7,700 pounds.

The challenge with using silver as a coating material is that, unlike aluminum, it tarnishes with exposure to air, specifically to sulfur.

The reason for going with silver rather than aluminium is a slightly improved reflectivity in the near- and mid-infrared (99.1 per cent at 10 microns), but also that the emissivity of the silver coating is around 38% that of aluminium, which reduces background in infrared observations.

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Subaru has earned a reputation for building vehicles that are well suited for winter. And among the brand’s current lineup, the most fun to drive for the winter is the WRX. This rally-bred sport sedan pairs a 271-horsepower turbocharged four-cylinder engine with a six-speed manual transmission and standard all-wheel drive to provide impressive traction and acceleration on any road surface.

No, we’re not joking. Wrap the Mazda MX-5 Miata’s wheels in winter tires, and this rear-wheel-drive sports car can churn through the white stuff with remarkable ease as long as it isn’t too deep.

"Like the family silver set," explains Tom Geballe, Gemini Senior Astronomer, "which slowly develops brown tarnish spots over time and must be regularly polished, the shiny silver on a telescope mirror also tarnishes rapidly reducing reflectivity and increasing emissivity. The observatory's engineers, however, can't just grab a cloth and some polish when the tarnish spots appear."

Edmunds’ car experts have four recommendations, including one that you’d never guess could be just as enjoyable to drive in the winter snow as it is on dry summer roads. They’re listed below in alphabetical order and are capped to stay under $40,000. All prices include the destination charge.

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Also, regarding the front/back surface point, if the back of the mirror is surfaced, you need to get the right shape on each surface, rather than just the front.

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Telescope mirrors and other mirrors used by scientists telescopes regularly do use a silver coating. See for instance here. However, aluminum coating are the norm (certainly for the large primary mirrors deployed in telescopes) because of durability reasons. I quote from the text linked to above:

It ain't necessarily so. Some large telescopes are using silver coatings. For example the Gemini telescopes (Boccas et al. 2006).

From a viewpoint of the material used, a front surface mirror has fairly simple, mostly mechanical requirements, such as the ability to polish it to the required smoothness, and stability to maintain the intended shape across temperature changes. Even so, the tolerances involved are so fine that meeting requirements is fairly non-trivial.

If you wanted to transmit light through the mirror, you almost certainly could not use such a honeycomb design, which (in its case) would roughly double the mirror's mass.

The Big Bend trim is the Bronco’s base trim level and it offers surprising comfort and practicality. It comes with a part-time four-wheel-drive system, all-terrain tires, and a hardtop with a rear window defroster and a rear window wiper. The turbocharged four-cylinder engine supplies up to 300 horsepower when running on premium fuel, and a seven-speed manual transmission is standard. Technically, the Bronco is priced below $40,000 to start but adding the destination charge puts it slightly over.

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The paper reports on durable coatings that reduces the tarnishing that favours an aluminium coating (as well as aluminium's superior performance shortward of 400nm). I guess that these are rather expensive, so aluminium is still the norm unless you want to be re-silvering the mirror very frequently.

Most WRX versions are priced under our $40,000 limit. We’d go with the Premium trim for overall value. It comes with cloth upholstery, heated front seats, heated side mirrors and a windshield wiper de-icer, and all-weather floor mats are an option. You can also get it with an automatic transmission.

Johannes makes a good point about durability. As a footnote, I'll add that aluminum has another nice property over silver, at least as far as your plot shows: constant reflectance over the visible spectrum.

That’s true of any Miata. The RF version is better for winter driving thanks to its exclusive weathertight retractable hardtop roof to better keep the cold out and the heat in. Only the Grand Touring trim level slides in under our $40,000 price cap, but it’s well equipped with leather upholstery, heated front seats and heated exterior mirrors. Though the Miata’s low-to-the-ground design limits winter drivability during heavier storms, the car’s playful handling can be a delight to experience following a light snowfall.

Driving in the snow isn’t enjoyable for many people. It’s cold, the roads are slick, and city traffic is often slow going. But there are ways to have a bit more fun in the wintertime. To start, it helps to have the right vehicle.

Nobody has yet mentioned the one aspect of silver that the graph depicts. Silver absorbs strongly near 315 nm. If you were interested in UV light from the stars, you would have a hole in your data (between 310 and 320 nm) if you used silver. Not only that, any light gathered with a wavelength less than 310 nm would require longer acquisition times.

I see that silver has a higher reflectance than aluminum. So why use aluminum instead of silver? If one wants the highest quality mirrors I assume that cost is secondary, so what is the physics that I am missing here?

Worse, glass used in most lenses (for example) is much softer and weaker than the Pyrex used in those telescopes, so it would almost certainly require a mirror that was still thicker and more massive and/or more elaborate support structure.