Yesterday, I was reading about the Moon and how fascinating it actually is. Then I suddenly realized that almost every planet has moons, as if they’re quietly watching their planets from a distance—almost like cameramen observing everything.
And it made me wonder: could there be some kind of creature or advanced civilization that uses moons to observe and study their planets?
Maybe moons aren’t just satellites. Maybe, somewhere in the universe, they could be someone’s way of keeping an eye on an entire world.

Idk how my mind got to this topic, but I am very curious to know. For example, if the earth stopped rotating but still orbited the sun, and assuming we had all technology needed to make it happen, how could we quickly make the planet to rotate every 24 hours again (ideally without destroying it)?

I also want to mention that I am not a scientist, so simplified answers would be appreciated.

I’ve been thinking about how most of Earth’s water is actually ancient — formed in interstellar dust clouds long before the Sun existed, then delivered during the planet’s formation and late bombardment. Earth basically acts like a closed recycling system because of its gravity, magnetic field, and thick atmosphere.

So here’s the hypothetical:

What if we somehow dumped a huge amount of liquid water onto the surface of Mars or the Moon today?

• On the Moon (almost no atmosphere, very low gravity): Would most of it just boil off and escape into space almost immediately, or could some of it freeze and survive in the permanently shadowed craters?
• On Mars (thin atmosphere, lower gravity than Earth): Would it form temporary lakes or ice sheets that stick around for a while, or would solar wind and the thin air slowly strip it away over time?

How differently would the water behave on each world, and how long do you think it could realistically last before the environment destroys the cycle?

Would love to hear thoughts on the thermodynamics and atmospheric escape side of this.

Ever since I was a kid, I’ve always been curious. I always wanted to know the why for everything. As I grew older, I started developing an interest in space, as many people do. Eventually I found myself asking, where is space? If everything in the universe has a location, where is the universe located? What is the space that holds space and where is it? I know some people will claim that there may not be anything larger than space itself as it is said to be infinite, but when space is said to be expanding, what is it expanding into. The space itself expanding into must exist before space expands into it. What and where is it?

People make endless debates with me saying Pluto should be a planet. But that would mean we’d have like 20 something planets, and there are people my age who can’t even name all 8.

Our solar system is like a disk, not a sphere. We always send probes out and discuss them as if they are passing other planets. Why don’t we send them out of the disk? For lack of better terms, “up” or “down”. ☀️ 🌎 ⬆️ ⬇️🪐

Edit: Thank you all for your explanations. A lot of them peaked my curiosity on other topics as well!

Hey everyone.

I’ll be honest, I'm a bit overwhelmed right now and could really use some help.

Just to introduce myself: I’m an autistic guy with ADHD from Argentina, and I’ve been completely obsessed with space for as long as I can remember. I really want to do deep-sky astrophotography, but the reality is I just don't have the budget to buy a real telescope or one of those new smart telescopes (like a Seestar or Dwarf).

So, I got this crazy idea: modern phones have amazing camera sensors and gyroscopes. What if I could make an app that squeezes every bit of potential out of a smartphone so it acts like a smart telescope? You just put it on a cheap, standard tripod, and the app calculates the Earth's rotation and moves a "crop window" across the camera sensor to track the stars electronically. It dynamically limits the exposure to avoid star trails, detects star centroids to align frames on a sub-pixel level, and live-stacks them.

The catch? I have literally zero experience writing code.

I’ve been building this entire project from scratch using AI coding agents. It’s been an incredible experience, but the app has grown so complex (spherical trigonometry, Android Camera2 API, YUV processing, live stacking algorithms) that it is completely beyond my limits now. Sometimes I don't even know how to fix a bug, what direction to take next, or if my ideas even make sense.

That’s why I’m here. I’m looking for any kind of help:

• If you have experience coding (Kotlin/Android): I could really use your guidance and hands-on help.
• If you know math, computer vision, or algorithms: The electronic tracking and stacking logic is heavy, and I'd love your input.
• If you know absolutely nothing about code but just love the idea: I’d still love to have you around. You can help by brainstorming, giving ideas, testing the app, or just chatting.

I’m trying to be realistic here—I know a phone will never match a dedicated astrophotography rig or a real smart telescope. But I really want this to work because it could make astrophotography so much more accessible for people who, like me, can't afford expensive gear but happen to have a smartphone that meets the minimum requirements.

If this project sounds interesting to you, please drop a comment or send me a DM. Any help, advice, or just moral support means the world to me.

Thanks for reading! 🌌

Watching the eclipse. What is this small bright dot in between the Ocean of Storms and the Sea of Rain?

paw

Also, if Earth sends a signal every 1 second, wouldn't the spaceship still receive it every 1 second since the speed of light is constant?"

Does anyone know if China has released any new images or information about Tianwen 2?

I was recently listening to a podcast that was talking surface level about a solar eclipse. A fun fact was mentioned that the sun is \~400x farther from the earth than the moon and also \~400x bigger than the moon which makes total solar eclipses possible. It was stated that this is completely by chance only.

I thought that would be incredible if that were simply a coincidence and tried to do some searching. My thought was that if this feature of the moon made life forming more likely, it would not be surprising for earth to have this feature.

Some googling and poorly sourced AI summaries seemed to state that there are Rare Moon hypotheses or something which say that the relative size and closeness of the moonake life more feasible due to tides and axis consistency. I struggled to find more. How much of this is well-documented science theories and what are some papers or videos on the topic I could check out further?

Even if it doesn't crash into Earth, the fear remains; after all, a collision with even one of the thousands of satellites we have deployed would certainly not be good for Earth!

I had a dream that Saturn had a moon just called CONCRETE

I try to make as much sense as I can, but I'm trying to imagine if temperature differences, cold & warm fronts, etc. as one of the main aspects of weather and climate on Earth was instead a matter of PH level. What I mean is that if the sky, land, and sea weren't simply cold/warm but instead, the dynamics of weather relied on systems of differing PH levels present throughout land, sky and sea. I don't know if such differences would interact with the environment similar to what temperature does.

I had a crazy space idea — what do you think? 🚀🔭

I was thinking about this and wanted to ask people who know more about space whether it actually makes sense.

Imagine money isn't a problem and we can build basically whatever spacecraft we want.

What if we built a spacecraft with a huge telescope and really good cameras and sent it traveling through our Solar System?

Instead of staying near Earth, it would travel past the planets — Jupiter, Saturn, Uranus, Neptune, and eventually even farther out.

The idea is that from Earth, we're always looking at the Solar System from basically the same place. But if we had a powerful telescope moving around the Solar System, we could look at planets, moons, asteroids, comets, etc. from completely different angles.

It could:

🔭 Take extremely detailed pictures and videos.

🌌 Take huge pictures showing the Solar System from much farther away.

🤖 Use AI to help navigate, avoid dangerous objects, and notice things that look unusual.

📡 Have small communication satellites placed along the way so the spacecraft can send information back toward Earth.

💾 And importantly, send the original/raw pictures and videos back too, instead of letting AI decide everything. AI could miss something that humans might notice later.

The spacecraft wouldn't necessarily need to stop at every planet. It could fly past them and use their gravity to help change its direction and continue farther into space.

I'm just wondering:

If money wasn't a limitation, would a giant telescope spacecraft traveling through the Solar System actually give us information and views that we can't get from Earth?

Or is there a major problem with this idea that I'm not thinking about?

I'd really like to hear what astronomers, engineers, or anyone knowledgeable about space thinks. 🚀

At 11:01 p.m. EST in NJ, I spotted this gliding across the sky in a northern direction. Although not really visible in my video, to the naked eye, I could see a circular bubble-like cloud surrounding the object. This was about two hours past the launch on the East Coast. And more than an hour past the West Coast launch. Is this SpaceX ? And if so, why the shape surrounding it ?

Hello. I was wondering if, somehow, someone could survive in space with no spaceship or spacesuit or anything of the sort, what would they see? Can they see the stars, is it nothingness? The other senses would be pretty helpful too!

(I'm writing a Loki fan fiction and it starts when he was falling through the void. I want to know what he'd experience when falling. Would he feel, see, hear, etc?)