# Tag Info

103

Make the Legend last through the ages So, Merlin telemagicks to 5000 years ago, presents the sword-in-cement LEGEND to some fancy king. Then he rigs up some scenario where the sword is found. People try and fail to remove the sword, the legend spreads. Merlin then causes some event (flood, landslide, magic POOFing, etc) to disappear the sword. The sword is ...

95

Merlin knows about metallurgy, and will place in the immediate surroundings of the rock (or even IN the rock) a sacrificial anode made of magnesium, aluminium, zinc or another suitable metal. A galvanic anode is the main component of a galvanic cathodic protection (CP) system used to protect buried or submerged metal structures from corrosion. By simply ...

71

Can there be hereditary Servants of the Sword? These folks would live nearby, working the earth etc but they take responsibility for periodically going out to visit the Sword and putting a fresh coat of grease on it. Maybe they could have special hats - worn only for the sword greasing, you know.

71

What your son wants, and in fact you describe /and when their opponent is vulnerable for the final blow, will say: "See you next time" and go home./ is counting coup Any blow struck against the enemy counted as a coup, but the most prestigious acts included touching an enemy warrior with the hand, bow, or coup stick and escaping unharmed.1 Touching ...

60

Getting caught in a thunderstorm is the most likely cause. This can happen even to experts if they are incautious enough to take risks with the weather. Here's an example with a paraglider. (I'll see what I can find for a hang-glider) Ewa Wisnierska was sucked into a powerful thunderstorm while training for the world paragliding championships in ...

59

It's hard to believe but I have some RL experience with freezing blood (cow blood!). It freezes rather well, but at lower temperatures (about -5C). When it freezes blood "essence" (this red-yellow substance) happens to be trapped inside ice crystals. When it freezes as snow — it is more like thin hailstone, like groats. Normal snow is sometimes ...

57

Let's say your magical sphere has radius $r$ of 10km (so just poking up into the outer atmosphere) and is at a temperature $T$ of 1,250K (so glowing a nice warm yellow). The total radiative heat flux from the sphere is given by: $$Q = \sigma T^{4}. 4\pi r^2 \approx 1.7 \times 10^{14} \mathrm{W}$$ Where $\sigma$ is the Steffan-Boltzman constant. A ...

54

Something like this has actually happened once already 100 years wouldn't be enough to turn the Sahara into a savanah, but it would be a good start. From this source we read the following (emphasis mine): But around 10,500 years ago, a sudden burst of monsoon rains over the vast [Sahara] desert transformed the region into habitable land. This opened the ...

53

Just make it so wood does not last on seawater Your planet has a variant of the Shipworm, similar to the Earth variety except that it contains its own cellulose-dissolving enzyme rather than relying on bacterial assistance to do this job. This would result in any unprotected wood in the seawater being leaky within a day, and riddled like a sieve within a ...

52

The eye is a region of mostly calm weather at the center of strong tropical cyclones. The eye of a storm is a roughly circular area. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. In strong tropical cyclones, the eye is characterized by light winds and clear skies, surrounded on all ...

51

Let's assume for a moment that there are bacteria living in clouds. These have to feed on something, but nutrition in clouds is scarce. The chances of collecting molecules with nutritional value increase with the surface area that can be used to collect them. Sometime during the endless evolution some bacteria managed to excrete a slimy substance that can ...

49

A wobbling pulsar will do the trick. Pulsars emit a lot of energy in narrow beams that come from their poles. The slowest ones flash every few seconds; make its tilt wobble so that it is not pointing at the planet all the time. In addition, wobbling causes the pulsar to shoot at different points of the planet's orbit through time. The planet is hit when the ...

46

Plant respiration Rainforests are famous for making their own rain. Plants transpire something like 98% of the water they take up. When you have a lot of plants, and it is already pretty humid, the result is lots of mist. Cold ocean currents Fog can form when the difference between the air temperature and dew point is less than 2.5 C. Water vapor in the air ...

42

Let it rust. Seriously. A thick chunk of steel is already going to last ages without any special treatment. It will corrode on the outside for sure, but this adds to the authenticity of just how old it is. Maybe build a gazebo over it to keep the absolute worst of the weather off. It'll be way more exciting when "he whom the wizard deems worthy" finally ...

41

Different approach, after the Comment on my other answer: Maybe that's just how immortal (or very, very long-lived people) always fight - it's how it's always been. Dwarves have fought each other like that because, well - for a human with a finite time to live, dying for a cause to make the (short) life of their children better may seem like an OK deal. If ...

41

Yes it is possible, if the planet has little axial tilt but an eccentric orbit. Then summer will be when it is closest to its sun, and winter will be when it is furthest away, which will be the same all over the planet — at the equator as well as in higher northern and southern latitudes.

38

You're in luck! We already have this action on Earth, in the Atacama Desert. Fog rolls in from the ocean, but the mist is so fine it doesn't fall as rain, hence preserving its desert-hood. Only a few plants are able to take advantage of the mist, so it still comes across as "deserty". There is a little lizard which lives there which has weird horns ...

38

Supernova. A type II-P supernova maintains a fairly constant brightness for several months, and one at an appropriate distance (something like 500 light years) will be as bright as the full Moon for that time period. It will need to be on the opposite side of your planet from its own star, as seen from where the planet is in its orbit. Betelgeuse will do the ...

38

Your desert glass pebbles are volcanic glass. In the US they are called Apache Tears. source These are unpolished, as found in the desert. When polished they are a very beautiful deep black and suitable for use in jewelry. Some of the round ones in this image ones look pretty close to that without polishing. https://en.wikipedia.org/wiki/Apache_tears ...

37

Decrease Gravity Explanation: The water droplets we experience on earth are mostly so small because of gravity: when a water droplet becomes too big, gravity rips it apart before it can get bigger (like when you're not quite closing a tap, the only reason it doesn't get bigger is because the mass of the droplet is bigger than the force "gluing" the water to ...

36

Not sure if this is what you're looking for, but what about geysers? There'd obviously have to be a ton of them (and maybe some one with more of a science background can speak to what that level of seismic activity would do to the earth), but that'd be a potential way to supplement evaporation. the way I envision it, the world is like ours except for it ...

36

Mount Kilimanjaro is located close the equator (03°04′33″S 37°21′12″E) but its 5895 m high top is covered with permanent snow . Even better, the Mauna Loa, located on Hawaii Island, can give you a good estimate of the distance between the snow and the beaches. Mauna Loa is the largest subaerial and second largest overall volcano in the world (behind Tamu ...

36

Winter warfare (at given temperatures, which I would not call "Arctic") maybe uncommon, but absolutely realistic. For example, in the XIII century, Batu Khan's conquest of Rus' (a predecessor of Russia) was conducted primarily by winter campaigns, when temperatures were certainly plunging below -10F/-23C. Steel is not particularly more brittle at these ...

36

What keeps my planet's water from irreversibly concentrating over time on the frigid wastes while the rest of the planet dries up? When ice piles up, it will exercise pressure. The closer to the terminator, the less the ice. As a consequence, pressure gradient will tend to push the ice sheet toward the terminator, where it will melt, returning water to the ...

36

For one thing, natural bushlands would get overgrown. Anyone who listens to world news knows that the south west of the US; California and Arizona especially, are prone to bushfires. So is most of the Australian outback where there is natural bushland areas. In Australia particularly, some species of tree are so integrated with the natural fire cycle that ...

35

That is a lot of rain Runoff will carve rivers as excess water goes to the ocean. Take a look at the basins to see what will happen. It appears there will be five basic river systems. There will be an Algerian system, gatheringr rainfall from the north and west of the Haggar ranges and emptying into the sea in southern Tunisia. There will be a Libyan ...

34

There is many studies (e. g. Yang 2013, Hu & Yang 2013, indirectly Joshi 1997 or Joshi 2003) that investigate this in context of tidally-locked planets of red dwarf stars. The reason is that such planets have to be very close to their parent star in order to maintain liquid water. Their orbital periods are short (15 - 40 days) and tidal-locking occurs ...

34

There are 3 types of natural glass: obsidian (volcanic glass), impactite (meteor glass), and fulgurite (lightning glass). Naturally round impactite is virtually unheard of. Impactite tends to have strong striations in the direction of impact that gives it more of a cleaved shape. It is also very rare for it to be transparent. Technically, a round ...

34

How cold does it have to be to freeze the waterfall? Obviously, below freezing. The colder it is, the faster the water will freeze. Depending on the size of the river and the brightness of daytime sunshine, it might have to be a long way below freezing. This waterfall (Kinder downfall) froze during a period of slightly-below-freezing weather, after a ...

33

Eucalyptus trees can form bubbles when it rains Combine a eucalyptus grove with rain and a high wind that blows the bubbles away as soon as they form and you have a rain of bubbles somewhere down the line. Video - Why do trees blow bubbles?

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