The name of one of the earliest spy satellites.

They took pictures onto a reel, and, when they had expended all of their film, dropped it into the sea.
To prevent the Russians from finding these canisters, they were sealed with a salt plug that would disintegrate after a short time. At least one canister was lost when it fell off-target and the Navy couldn't get to it fast enough
The idea behind retrieval was that a helicopter would fly out to the dropped canister from a carrier and pick it up.
Later on a man in NASA figured that an airplane could intercept it in the parachute stage; this was more difficult but also made it even more ridiculously impossible for Russians to capture the canister.
When the guy who thought up the fast aircraft-retrieval idea tried to push it into use, the higher-ups weren't convinced the film would survive being catapulted forward as the airplane caught it ... So he latched himself into a harness and had an aircraft pick him up.

Fortunately for him, it really was safe, so he didn't die a horrible horrible death.

Technical Info

  • Camera Type: 70mm for all variants of the Corona
  • Focal Length(in): 24in for all variants
  • Best Ground Resolution (apprx.): 25ft for KH1-4, 9ft for KH-4a, 6ft for KH-4b. (KH1-4 are kinda like build numbers, you understand. KH stands for KeyHole, the name of the project)

Corona (the beer) is a product of Grupo Modelo, a Mexican brewing giant (Anheuser-Busch "directly and indirectly" controls 50% of the company according to their website). Grupo Modelo started out in 1925 as "La Cerveceria Modelo," a comparatively small brewery in Mexico City. By 1979 they created an International Division, and pressed hard to export their product to the United States. As of today, they are responsible for 80% of Mexico's total beer exports, and their most popular product, Corona Extra, is currently available in over 150 countries.

Grupo Modelo is responsible for brewing the following Mexican beers, some of which are more popular than others:

Corona Extra, their most popular brand, is reputedly the number-one selling beer in Mexico, as well as the number one imported beer in the US. This clearly contradicts the claims of an above writeup by Inyo, but the information came straight from Corona's website so it's possible they're exaggerating their popularity. Corona Extra is relatively light beer, and tastes pretty bland without a wedge of lime (in my opinion -- some people require salt, also). As of the time this was written, Corona Extra is 81% recommended on epinions (out of 175 reviews), with a four-star average rating. One of the most common complaints is that it's expensive (usually $5.99 a six-pack or more) and tastes unsubstantial or even unpleasantly bitter without a lime. The first time I drank Corona, I went through four bottles without any limes in the vicinity, and found that it tasted worse and worse as I drank. According to their website, Corona Extra contains an average of 148 Calories per bottle, and has an alcohol content of approximately 4.6% (by volume).

Corona Light is only available in the United States. Despite the fact that Corona is very light to begin with, there was (apparently) a market in the US for an even lighter, lower-calorie version. Corona Light contains a mere 105 Calories per bottle, but Corona's website won't disclose the alcohol content. I searched high and low desperately seeking the alcohol percentage, but alas could not find it anywhere. Corona Light is only 61% recommended on epinions (out of 23 reviews), with an average rating of three stars. The biggest complaint is that it's a light version of an already light beer.

Modelo Especial comes in a characteristically "cute" stout, fat bottle, but is also available in a can. It's a pilsner beer, essentially in the same category as Dos Equis Special Lager. Corona's website discloses its caloric content at 145 Calories per 12 ounce serving, but alcohol content is not available; I've seen figures between 4.4% and 6.0%. It's 100% recommended on epinions, but there have only been seven reviews written so far. As of 12/19/01 I've tried this beer, and found it to be most enjoyable. It even tastes good without lime and salt, but is awesome with them. Based on the fact that I felt a buzz after one bottle having eaten a large burrito, I'd have to intuitively say that the alcohol content is between five and six percent.

Negra Modelo comes in a characteristically cute stout bottle also, and is more along the lines of Dos Equis Amber (Grupo Modelo considers it to be in the style of a true Vienna lager). Negra Modelo is more of a full flavored, dark beer, but once again, the most common complaint is that heavy-beer lovers might find it too light. Negra Modelo is 100% recommended on epinions (out of 23 reviews), with an average of rating of four stars. I found it hard to find the alcohol content of this beer as well; one site claims 6.0%, but this is the same site that reports a 6.0 for Modelo Especial, so who knows how reliable that information is. According to Corona's site, one 12 ounce bottle contains 169 Calories.

Pacifico Clara has a colorful, gold label, which is accompanied by a slightly more hoppy, gold taste (compared to Corona, at least). It was first made available in the US in 1985, and is now relatively popular in Canada, Central America and South America, Australia, and Europe. Pacifico was the first Mexican beer I've ever tried with a lime, and I found it to be most delicious. Then again, I had three Fat Tires in me at the time, so my palette was a little distorted and my judgement was perhaps impaired. Pacifico is 94% recommended on epinions (out of 16 reviews), with an average rating of four and half stars. Common complaints are that it isn't as hoppy as it's made out to be, and it's hard to find. Corona's website reports an average of 146 Calories per 12 ounce serving; discloses an alcoholic content of 4.5%.

If you're concerned with the perils of drinking something made with Mexican water, heed Corona's website, which claims that "All Modelo breweries receive their water from deep wells and it is treated and purified to international industry standards." I've only seen one reviewer who claimed to suffer from diarrhea after drinking a Modelo beer (Pacifico Clara), and I highly doubt the veracity of his claim.

I realize in some ways this is sort of a metanode that might make more sense if it were called "Grupo Modelo." On the other hand, it seems far more likely that people interested in Grupo Modelo would be searching for "Corona." If you think this should be moved, give me a MSG. I debated it for some time and thought corona made the best home.

A corona (Latin for crown) is a form of sonnet sequence wherein the last line of one sonnet becomes the first line of the next, and the first line of the sequence is repeated in the last line. In more modern poetry, the repetition can be somewhat less strict, but the lines must strongly echo one another. The corona can include any number of sonnets, as long as the very last line links to the very first. A seven-sonnet corona ("La Corona") opens John Donne's "Holy Sonnets," and Lady Mary Wroth includes one twice as long ("A Crown of Sonnets Dedicated to Love") in her Pamphilia to Amphilanthus.

As with other linked poetry (the villanelle, the pantoum), the repetition in a corona can be used to set the poem's tone. Wroth's corona, though "dedicated to love," centers around the theme of a labyrinth, and the interlacing of the sonnets makes the poem itself evoke the twisting and turning of a maze. Mary Moore, in Studies in English Literature 1500-1900, writes:

Lady Mary Wroth's 1621 sonnet sequence, Pamphilia to Amphilanthus, alludes to these contexts with the opening of the corona that crowns the sequence: "In this strange labourinth how shall I turne?" The temporal and spatial vagaries of "this" and the punning "labour" of Wroth's spelling evoke the poem itself as intricate space and Pamphilia's thought as labyrinthine source of mimetic writing. Like the mazes of classical literature, architecture, and art familiar to Renaissance readers of Pliny, Ovid, and Virgil, Wroth's artifact represents perplexity even as it perplexes.

In atmospheric optics, a corona is a series of colored rings that appears around a luminous source, typically the sun or moon, resulting from the scattering of light by particles of relatively uniform size, typically in the range of 20 µm in diameter. If the particles are too big or not uniform enough, or if the layer of particles is too thick the corona will degenerate into a hazy white disc. In the case of the sun or moon, these particles are usually water droplets or ice needles in thin altostratus, altocumulus, and sometimes cirrostratus clouds, although a corona can also be generated on a small scale using terrestrial light sources and any of a wide variety of particulate matter.

The classic corona is rather small, with an angular diameter of less than 5°, as compared to the much larger phenomenon known as a halo. The corona typically consists of a bright aureole, bluish in the center and brownish on the edges, surrounded by a series of outer rings ranging from blue on the inside to red on the outer edge, often passing through green and yellow in the middle. It is these outer rings that are most properly termed the "corona", although term is often appled the entire phenomenon.

Coronae are easiest to see around the moon, because the moon is not too bright to look at, but occur just as commonly around the sun, where they are much brighter and potentially more spectacular. A simple way to observe a corona is to block out the sun with your hand or other object, leaving part of the corona in view. Otherwise, special goggles or other viewing apparatus may be used. The problem is essentially the same as trying to view a solar eclipse.

To view an image of a corona, see


The corona is the tenuous plasma envelope around the Sun. It is the outer layer of the atmosphere of the Sun. It has no clear outer boundary; the edges constantly are blown away into space as the solar wind. This writeup will start with a discussion on how the corona is observed. Then, an interesting and poorly understood physical phenomenon is discussed.

Observing the corona

In order to study the corona, it is nice if one can actually observe it. The major problem with observing the corona is that it is very close to the Sun. As such, the Sun will saturate your eyes, making it impossible for you to see the corona. In fact, if you stare at the Sun, it will soon be impossible to see anything, as it will blind you. The Sun is more than a million times more bright than the corona 1,2.

The only moment at which it is possible to see the corona without any equipment is during a total eclipse. It is visible as a fairly faint, whitish halo around the Sun, that looks most like a piece of fluff or a cloud with streaks it. In terms of size, it is much larger than the Sun, especially if we consider the spherical symmetry. It certainly does not look like an uniform sphere, like the Sun does. It is noted that eclipse glasses are recommended when seeing a solar eclipse, especially before it is total.

Astronomers observe the corona using a coronapgraph. This is an instrument that blocks out the direct light from the Sun (or another star) and, as such allows one to see the corona. A simple design that does this consists of a disk that blocks direct sunlight, but more complicated designs are possible as well2.

Astronomers have observed the corona using a spectrometer 3. A spectrometer measures the light emitted by atoms, molecules or ions. Because each kind of atom or molecule has its own spectrum, that is unique like a fingerprint is unique among humans, this allows identification of the ions in the corona. One of the most prominent species is an iron ion that is ionized 14 times 4. This requires an enormously high temperature of over 1 million kelvin.

Coronal temperature paradox

The surface of the Sun is not more than about 6000 kelvin, tops (this is about 5700 degrees Celcius). Having such a hot "envelope" around the Sun is akin to turning on an oven and noting that the outside is yellow-hot, while the pie in it is freezing. It isn't as much a problem of energy - indeed, the corona has a density that is 1012 times lower than the body of the Sun, so heating it requires relatively little energy - but more of a problem because heat flows from hot to cold an not vice versa. This is a corollary of the second law of thermodynamics.

So why does this happen? The short answer is: no one knows for sure. The most plausible theories involves magnetic reconnection and so-called wave heating, in which sonic waves compress the corona and as such create local increases in energy.


The corona is a very tenuous and very hot layer around the Sun. It is normally not visible, because the light from the rest of the Sun is so much brighter. The reason why it is so hot is currently not known, although there are theories that can partially explain it.



Co*ro"na (k?-r?"n?), n.; pl. L. Coronae (-n), E. Coronas (-nz). [L. corona crown. See Crown.]


A crown or garland bestowed among the Romans as a reward for distinguished services.

2. Arch.

The projecting part of a Classic cornice, the under side of which is cut with a recess or channel so as to form a drip. See Illust. of Column.

3. Anat.

The upper surface of some part, as of a tooth or the skull; a crown.

4. Zool.

The shelly skeleton of a sea urchin.

5. Astrol.

A peculiar luminous apearance, or aureola, which surrounds the sun, and which is seen only when the sun is totally eclipsed by the moon.

6. Bot. (a)

An inner appendage to a petal or a corolla, often forming a special cup, as in the daffodil and jonquil.


Any crownlike appendage at the top of an organ.

7. Meteorol. (a)

A circle, usually colored, seen in peculiar states of the atmosphere around and close to a luminous body, as the sun or moon.


A peculiar phase of the aurora borealis, formed by the concentration or convergence of luminous beams around the point in the heavens indicated by the direction of the dipping needle.


A crown or circlet suspended from the roof or vaulting of churches, to hold tapers lighted on solemn occasions. It is sometimes formed of double or triple circlets, arranged pyramidically. Called also corona lucis.


9. Mus.

A character [&pause;] called the pause or hold.


© Webster 1913.

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