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Comment by helsinkiandrew | Hacker News Reader

An orbital period of 2.73 days would mean there's no (earth like) seasons and agriculture would not be constrained to growing things at specific times of the year. A wheat farmer could split their farm into sections and be sowing and harvesting continuously.

That's assuming there isn't a cycle from freezing to boiling every 2.73 days.

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That close to a star, the planet's rotation is probably tidally locked with its orbit, which means there's no diurnal *or* seasonal cycle. There's a summer hemisphere in permanent daylight; a winter hemisphere in permanent night; and a temperate twilight zone in between.

Solution: train-farms! Choo-Choo!

That would be as windy as Contrevent

Probably not. It's not hard to notice that while volatiles may flow from the hot side to the cold side, it's generally a one-way trip. Most attempts to model such a planet as habitable even on the thin strip involve trying to hypothesize some way that the volatiles could end up circulating rather than simply making the one-way migration, but personally I'm yet to hear a convincing way that could happen. And that's for the lower bar of "is life possible at all", not the much higher bar of "could we be happy living there".

YMMV, since it's all opinion and conjecture right now.

But in general I wouldn't expect much wind. The hot side is in vacuum because the only volatiles there are the ones just baked out of the fried ground or perhaps some volcanic activity, and the cold side is in vacuum because everything's frozen, and if there is some tiny pressure gradient you'd never notice the resulting "wind" as the vacuum flows past you, probably at rates roughly comparable to what the ISS experiences as "wind" in its low Earth orbit.

The theological implications of finding planets even more hospitable than earth will be interesting.

Mirroring the fact that the cephalopod eye doesn’t have a blind spot unlike the vertebrate one.

Oh yes we still have theology. I don't know why. But as long as good books like Scott Alexanders Unsong tell me that American Pie is a song about the old testament, I do get entertainment out of it.

Training your mind to find patterns everywhere can be fun, unless you get QAnon out of it. Or, IMHO, religion that influences states or bothers non-followers. Contrast the good things, though: The aforementioned authors shows in Unsong that "Harry Belafonte - There's a Hole in the Bucket" is actually about the singluarity in AI/AGI development.

http://unsongbook.com/ for the curious:

“Erica,” said Ana calmly, “you’re going about this the wrong way. When Aaron is like this, you can’t argue against him. You have to beat him at his own game.”

“What?”

“For example,” said Ana, “Aaron, I propose that the Chevy does not represent the Tribe of Levi, but rather the Tribe of Issachar.”

“Huh?” I asked. “Why?”

“Because,” she said, with an ethereally beautiful smile, “a Chevy is a car.”

“AAAAARGH!” I said. “AAARGH AAAAARGH AAAARRGH AA – ouch!”

Given that humans evolved to live on Earth, isn't it quite unlikely that we'll find planets that are more hospitable (to us) than Earth?

Invasive species evolved to live in the environment in which they evolved. Wouldn't it be quite unlikely that they'd find environments that are more hospitable (to them) than their native habitat?

It is quite unlikely! Most species don't turn invasive.

The mutants will find the other planets more hospitable.

Why do you say that?

Come to think of it, most major religions don't treat the earth as something special for humans. In the Abrahamic faiths it's specifically not our natural home, which is why we have so many issues. In the Hindu faith, from what I understand, it's also a place of suffering we are ultimately trying to escape. Buddhism also has much the same view.

Buddhism tries to escape from all forms of the existence (31 realms - or dimensions of existance) , not just from this earth or universe.

Makes me wonder how much of the day sky is taken up by the star during daytime. Would be quite the view at that distance.

It's a sphere next to a point source of light.

So I'm gonna guess... half?

They didn't ask how much of the planet is covered in light. They mean how large does the star appear in the sky from the planet's surface.

The innermost of the planets is about 2.8 million kilometers away from a star with a diameter of 217,000 km, so the angle (in radians) would be about 217,000/2,800,000 = 0.0775 radians or about 4,4 degrees. The sun is about 30 arc minutes or half a degree, so this star would have about 9 times the diameter, or 80 times the area of our sun.

(Double-check: this planet is about 1/50 as far from its sun as earth is from our sun, and its sun has about 1/7 the radius of our sun. That would give a rough estimate of the relative size of that sun in the planet’s sky of 50/7, so say 7 times as large as our sun is to us)

I would call that large, but not enormous.

(This ignores effects on perceived size of differences in the light spectrum and brightness of the two stars and differences between the atmospheres of this planet and earth)

That's roughly the size of Jupiter at a distance roughly 7 times that of the moon from Earth. At those distances you could probably see features of the star the same way we see craters on the moon.

Wheat is hard to grow in permanent twilight. And, with no water, because it is all frozen onto the night side.

This is no more earthlike than Mars.

That's gonna make it tough to keep track of when the pumpkin spice latte goes on sale. "Shoot, I missed fall again, guess I'll have to wait 48 hours for it to come around again!"

Given that most of the emitted light is infrared, there would be other challenges.

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