Moons of all the planets in our solar system | Hacker News Reader

Moons of all the planets in our solar system

go-astronomy.com

228 pointsmooreds33 comments

I'm surprised we haven't seen more hard sci-fi in the jovian or cronian systems. While constant 1g acceleration drives open the whole solar system to the ~month travel time that benefits stories, much more realistic accelerations (or limited fuel) can still manage the same within those systems. Add to that the plethora of interesting moons, rings, and gravitational points to focus people and material around and the action should flow quite naturally.

See The Expanse Season 2 (it's amazing).

I think it is because aliens are more interesting than moons. Anyways, Expanse is amazing, I hope they improve for the last book in the series. Tiamat's Wrath was not the best.

Agreed on Tiamat's Wrath although it wasn't the worst either.

Absolutely! Persepolis Rising was amazing though. I am hoping the next book will be similar.

The books are great and the TV series is now on Amazon Prime, with future seasons coming. Anybody on HN ought to be watching it.

... the TV series is now on Amazon Prime, with future seasons coming.

Fortunately Amazon took it. If after three seasons of slow development it ended where we start to see answers, I would have considered it a scam. Not so insulting as Gallactica, but definitely annoying.

I had no idea it had been renewed by Amazon! You have made my evening, kind internet stranger.

If an entire Sci-fi continuity were limited to just Sol and Alpha Centauri, this by itself would constitute an inexhaustible number of potential settings. In addition to planets, moons, asteroids, dwarf planets, Oort cloud and Kuiper belt class objects, there could also be space stations numbering in the tens of millions. Such a setting could use known physics, yet be incredibly vast. The Expanse is going in this direction, but doesn't go that far, and doesn't stick to known physics. (Though it remains closer to it than almost all Sci-fi continuities out there.)

> If an entire Sci-fi continuity were limited to just Sol and Alpha Centauri, this by itself would constitute an inexhaustible number of potential settings.

"Saturn's Children" by Charles Stross is a good one (unfortunately he had to do away with humans to keep the space opera physically realistic).

Mostly humans with radiation repair nanomachines and shielding could do just fine, I think. (Saying more would spoil Saturn's Children.) Humans commanding autonomous drones should figure more into Sci-fi. "Away teams" of drones in real life space fleets should be more prominent. Instead of a transporter shifting bodies, we could have the shifting of points of view through VR teleoperation. (Which is really what a transporter was for in the original Star Trek series: Changing locations with minimal production expense.)

The radiation environment around Jupiter is a real kick in the nuts to hard sci-fi involving human exploration there.

The Red Rising series has significant plot points in jupiter and beyond. Fantastic books.

There is a comment on the site that the Galilean Moons of Jupiter can be seen with the naked eye under dark skies. I've known people who might have eyes good enough to do that, but for the rest of us even a modest pair of binoculars is enough. To me, it's one of the funnest things you can view in the northern hemisphere without getting out more serious equipment. (Another would be the Orion nebula. If you can set the exposure on your camera, you can even photograph it, although without tracking it'll be blurry.)

The wikipedia page has an "amateur" photo of the Orion Nebula that highlights your claim, it's pretty glorious.

https://en.wikipedia.org/wiki/Orion_Nebula#/media/File:Backy...

That is one beautiful sight: https://en.wikipedia.org/wiki/Orion_Nebula#Image_gallery

Note that this photo is not how it would look without a telescope or very good telephoto lens (with tracking), but it will still be visible

you could use fixed tripod with 500/focal-lenght rule then stack with DeepSkyStacker.

The Galilean moons are hard to see with the naked eye because the light from Jupiter is overwhelming. It is much easier if you use a distant object like a lightpost to just barely block out Jupiter.

Wasn't Galileo first to observe them with his telescope or were they mentioned somewhere before? I assume back then the skies were darker and people probably had better eyes so if they are observable I would assume somebody would have mentioned them.

There are a few confounding factors:

1. Jupiter is very bright.

2. The moons aren't always visible (they're behind or crossing Jupiter).

3. The magnitude of the moons changes with the relative positions of Earth and Jupiter.

It's possible that Galileo was not the first to see them, but if you don't know what they are or how you managed to see them, you're probably not going to be able to get anyone else to believe you. The telescope allowed Galileo to track their movement and also to convince others, who could also look through a telescope and see them easily.

There is an argument that a Chinese astronomer observed and documented a Jovian satellite in the 4th century BC. [1]

[1] http://en.cnki.com.cn/Article_en/CJFDTOTAL-TTWL198102000.htm

Try viewing the jovian moons in winter when the atmoshpere is stable. Try with binoculars first to see where the moons are then try to focus your eyes on the system without the binocs. My eyes are terrible but I see those moons every winter To see the red spot you will need a telescope. To see it for more than a few seconds you will need an expensive telescope hopefully with auto tracking and the red spot must be in view When I was a young boy a person showed me the rings of Saturn and it blew my mind. I've since bought tools to help me see not only Saturn's rings but to study the Cassini divisions separating the rings There are all kinds of cool stuff overhead

If you want to play with this data, it's available in various formats [1]

I happened to use this last week because we needed test data for a community tree in an app we're building. There are nine communities, and we needed test cases with 0, 1, and many subcommunities. This not only provided ready test cases, but the team is learning celestial facts while working on the feature!

[1] https://devstronomy.com/#/datasets

Very nice summary of the moons. I showed it to my kids.

Though I was surprised to find a scientific astronomy related page using inches and Fahrenheit units.

Though I guess the target audience it has been made for is perhaps US based school kids, but the page works really well for anyone across the world.

It's interesting to note that there is no well-defined lower limit on the size of what can be called a moon. So I can call a dust particle a moon as well.

Whenever people say they were born too late to explore the earth or too young to explore space i dont understand it. Something like 90% of the objects in our solar system have been discovered in the last ~15 years. There's tons more out there. Sure the major planets and their moons are here, but you scroll to the bottom of this list there's unconfirmed dwarf planets. And likely moons of them as well

The last trip to Pluto reminded me of being a kid again, when I pored over the newspaper looking at Voyager's trips to the gas giants.

Is any of the moons in solar system having smaller moons orbiting them?

Apparently no [0]

[0] https://earthsky.org/space/can-moons-have-their-own-submoons

Not that we know of, but there are asteroids in the belt that have their own satellites / are binary systems.

It's theoretically possible, but not likely. The Earth-Moon-Sun system is fairly stable because the Earth and Moon are relatively far away from the Sun and everything else. When we put a satellite in orbit around the moon, the gravity of the Earth is much greater when the satellite is on the Earth's side, and much weaker when it's on the other side of the Moon. Those forces destabilize the orbit rather quickly and corrections have to be made using fuel.

If the Moon were much further away, the Moon could have a moon of its own. But the further away it gets from the Earth, the more likely it is to be influenced by other objects like other planets or the Sun.

While not exactly the sub-moon you're looking for there are some interesting objects that come close.

Co-orbital moons, like Saturn's Janus and Epimetheus, are moons that are in stable orbit-swapping configurations. https://en.wikipedia.org/wiki/Co-orbital_configuration#Co-or...

Then you've got asteroids that are contact binaries that also have moons, like 216 Kleopatra. https://en.wikipedia.org/wiki/216_Kleopatra

And finally, you have 624 Hektor, which is a Trojan of Jupiter (stable solar orbit near Jupiter's L4 Lagrange point), that is a a likely contact binary that has a moon. So it's orbiting the Sun, while "orbiting" Jupiter's L4 point, while all 3 components (the two halves of the contact binary, and their moon) orbit the center of mass of their own little 'Hector system'. https://en.wikipedia.org/wiki/624_Hektor

Is there a CSV somewhere?

Devstronomy project aims to provide datasets related to astronomy in an accessible format (CSV, JSON, SQL).

https://devstronomy.com/#/datasets#csv

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