21 votes

Make solar eclipses exceedingly rare, but still have new moons

Just shrink the moon by 6%, and there will never be another total solar eclipse, but new moons will still happen as normal. The moon will be too small to fully cover the sun, so there will be partial ...
  • 19.5k
19 votes
Accepted

How does a Game of Thrones-style hyperwinter occur?

LONG-PERIOD VARIABLE STAR The magnitude of variable stars vary over time - up to 4 years. This is a bit short for Game of Throne-style long winters, but in a fictional setting, it is not a far ...
17 votes
Accepted

Earth-like Moon around the Gas Giant. Eclipse length?

For the TL;DR, see the bottom of this answer. Okay, so first of all, the orbital period of the gas giant around its star is $256 \times 24$ hours, and I'd like to establish the distance from the ...
  • 28.7k
15 votes

How does a Game of Thrones-style hyperwinter occur?

For it to have "little children [to be] born and live and die all in darkness" then the planet would be in darkness for ~20 years; if this is regular event then most life would die. If you ...
  • 2,013
11 votes

How does a Game of Thrones-style hyperwinter occur?

Planetary shenanigans. If you have a planet with a "wobble", or a significant axial precession, in addition to a (slightly) eccentric orbit you could have periods of time where a region/...
10 votes
Accepted

Make solar eclipses exceedingly rare, but still have new moons

Keep sun and moon sizes, make the orbit of the Earth around the sun more excentric and with a smaller mean distance. The new moon is unaffected, but full solar eclipses will only happen if the eclipse ...
10 votes
Accepted

How long would this eclipse last?

Let's establish some notation: The star is labelled $S$, the giant planet is $P$ and the moon is $M$. The diameter of the star is $d_S$, the diameter of the planet is $d_P$ and the diameter of the ...
  • 76.7k
9 votes

How does a Game of Thrones-style hyperwinter occur?

Volcanicity The OP clarifies It's not supposed to be a regular but exceptionally long winter that's a part of a recurring cycle of seasons; it's supposed to be a long and unnatural one. This rules out ...
  • 11.3k
9 votes

What would an eclipse with a translucent crystal moon look like?

This will actually look remarkably like a total eclipse on Earth. Since the crystal the moon is made out of presumably has a refractive index greater than one (quartz is 1.46, sapphire 1.77 and ...
  • 20.6k
8 votes

What would the Total Eclipse look like on a planet with rings?

First of all, realize that the rings themselves cast their own shadow on the planet. Here is a photo of Saturn during a time that the sun is at a rather oblique angle. If you live in those shadows ...
  • 434
8 votes
Accepted

A self-eclipsing orbital ring

The setup and the equation Let's look at the geometry involved here. I created two diagrams: On the left, we have the star of radius $R$. On the right, we have a cross-section of the ring. The center ...
  • 97.8k
8 votes

How does a Game of Thrones-style hyperwinter occur?

Snowfall The record for yearly snowfall in the United States is was in 1998 when 95ft of snow fell around Mount Baker in Washington between July 1, 1998 and June 30, 1999. Keep in mind that this is a ...
  • 21.2k
7 votes
Accepted

How long does it take for an eclipse to cause the ocean surface to freeze?

At least a decade In another question, I calculate that the time it takes for the Earth to radiate off enough of its heat to drop the uppermost 100m to freezing would be 281 days. However, that isn'...
  • 84.5k
7 votes

Make solar eclipses exceedingly rare, but still have new moons

Why not make the moon's orbit precess? If the precession chases the sun (from the perspective of earth) while staying a bit off from it, you could keep new moons as common as always and eliminate ...
6 votes

What would happen to Earth if it were eclipsed for nearly 10 days?

Typically the temperature difference between day and night is 10 C. So at first approximation, it drops 1 C/hour. So if you started at a middle of the road temp, of 20 C, you'd be down to freezing ...
6 votes
Accepted

How could the government trick the entire world into thinking there will be an eclipse when there isn't?

I don't believe there is a way that a government could convince the population of an eclipse or significant astronomical event without a significant amount of collaborative material. I would have ...
  • 3,574
6 votes

World with frequent lunar eclipses?

Take Earth and Moon, and make the orbital plane of the Moon around the Earth to be in the orbital plane of the Earth around the Sun. In this way each lunar month you will get a solar eclipse and a ...
  • 248k
6 votes
Accepted

Is there a way for a permanent Lunar eclipse, or another Object to always be in Earth's shadow?

It is not possible for an object to be in the shadow of Earth permanently - although it could be in the semi-shadow called penumbra, the full shadow (umbra) does not extend that far. There is a ...
  • 2,670
6 votes

How does a Game of Thrones-style hyperwinter occur?

La Niña, but bigger Climate sciences are hard. You can always have a huge ocean, handwave "big ocean, big currents", and have an unpredictible temperature oscillation that does this.
  • 610
5 votes

What would happen to Earth if it were eclipsed for nearly 10 days?

Lets assume that the eclipse is formed by something else - say some shade squares an ancient civilization left over from when they were building a dyson ring - and for some reason it causes a (...
  • 6,393
5 votes
Accepted

How can I lengthen a total solar eclipse on an earth-like planet?

The easiest and more effective is to pull your moon nearer to planet so it will have a larger apparent size and you'll get both more frequent and longer lasting eclipses. You will be limited by Roche ...
  • 17.1k
5 votes

Make solar eclipses exceedingly rare, but still have new moons

Resonance. Pick a ratio of the lunar orbital period to the solar orbital period such that the moon normally in the wrong part of it's orbit when it's both directly sunward and in the plane of the ...
5 votes

Properties of a mysterious celestial body that creates a permanent eclipse on earth

Think of a trapezoid. The shorter parallel side is Earth's diameter, ~6,400 km. The longer parallel side is the Sun's diameter, ~696,000 km. The distance between the two sides is the distance between ...
  • 33.3k
4 votes

Small eclipse on earth

A geostationary satellite can only be placed above the equator, and therefore could create an eclipse only on and around the equator (assuming it has the right size). Not very useful to observe ...
  • 248k
4 votes

Small eclipse on earth

A much cheaper way to create an eclipse like effect is a coronagraph. A coronagraph is a telescopic attachment designed to block out the direct light from a star so that nearby objects – which ...
4 votes

Small eclipse on earth

You can put your umbrella in the Lagrange point between earth and sun (there are a few satellites positioned there observing the sun), trouble is L1 is 1.5 million kilometers away, so your umbrella ...
  • 3,502
4 votes

How long would this eclipse last?

Using a completely comparative approach, rather than a direct calculation approach, here's my best answer: Totality of an eclipse involving the actual Sun, Earth, and Moon can last up to 7 minutes ...
  • 4,064
4 votes

Always night in one hemisphere. Is it viable?

Geometrically speaking, you need the moon to have its rotation synchonized with the planet's revolution around the star (thanks to David Robie for the vocabulary clearup). I believe this is possible, ...
  • 1,111
4 votes

Is there a way for a permanent Lunar eclipse, or another Object to always be in Earth's shadow?

Not possible with current configuration To have an object perpetually in the earth's shadow, it must circle the earth at the same rate that the earth circles the sun, in order to keep the earth ...

Only top scored, non community-wiki answers of a minimum length are eligible