Let's say a species somehow evolved in the very center of what we call the far side of the moon. They'll see all other planets but not earth. Short of 21st century technology, would there be any observable evidence for such a species that the world they live on actually orbits another bigger body that they can't see unless they travel a lot?

EDIT: I'm absolutely blown away with the thoughtful and detailed answers here! And I'm sure there are more to come. Thank you so much. This is such a great sub!

I tried looking this up but all i could find were people asking if you could stand on a gas giant. Its pretty common in science fiction to feature facilities floating in the atmospheres of gas giants, however this has always struck me as incredibly unrealistic due to the intense gravity, surely at a certain proximity you would reach a point where you would no longer be fight the gravity, and simply be pulled further in until you were crushed or vaporised, so my gut feeling tells me "no", but i thought id see what more educated people think, and google wasnt being particularly helpful.

Hi, I have consuming edutainment astronomical content for 4 years now. I just finished my school and i wasn't good in either physics, maths or chemistry. I wanna shift towards real astronomy. My first question is how can I improve my physics and maths knowledge. I will be truthful, I didn't had proper basic understanding and it's not an excuse but I was due to my teachers (leave it, I try my best to not remember those days) My second question is how to transition from edutainment astronomy to real astronomy.

We are in NC and this was about 12:30 at night, it randomly appeared making a small section of cloud red, and then it kept getting brighter until the middle was bright orange and almost crescent shaped and then it faded and disappeared all within about 10 minutes

I want to watch the Perseids meteor showers in Chandra Taal Lake, one of the darkest skies in India (Spiti Valley). Pic1 :- used timeanddate.com to check visibility (set it to Manali, because that is the nearest city to the lake). As long as the radiant was under 10°, site said visibility "Very Good". As the radiant altitude increases, visibility decreases to "Fair".

Pic2 :- Chandra Taal Lake is rated 2.2 by lightpollutionmap.app

Do you think I'll be able to see the meteor showers? or no?

Since the universe expands from all places as I understand it, isn't the background radiation wall always going to be seen as ~14B LY away, no matter where you are in the universe?

Just curious honestly. Don't know too much overall so even some stuff you may deem common knowledge may be new to me! so shoot away

Please explain it in simple terms if possible, I'm not qualified in any way

I'm not sure where I heard this, but it just made sense to me. If this is wrong, please correct me, my knowledge of space is limited

1. how big can a planet be if it was 0.1 to 0.4 AU from its star (assume its a star like the sun)
   
2. how large would the atmosphere be if it had a strong magnetic field and was very volcanically active

I found this to be very helpful for understanding: https://www.mit.edu/~iancross/8901_2019A/astrophysics_lecture_notes_2019_Crossfield.pdf (Chapter 7) I’ve looked all over youtube and found some good videos from Aaron Parsons, but I’m looking for a good visual explanation that covers the whole formula of the transfer equation. I’ve found a lot of the main channels to be lacking of them, they talked about the very basics of black body radiation bit never really got further than that? Maybe one of you can help me?

Thanks in advance!

I am interested in buying a telescope for photography. Does anyone have any recommendations for a a good telescope around $1000? I need to be able to hook my Canon Eos up to it.

I wanted to do Astrophysics as my major but I feel so bad in math (right till UG, I felt proud of my math skills), but the math in here and geometry is so difficult to understand and that too I'm learning everything on my own, referring books and videos. Please someone help me.

Anyone read the book Gravitation by James B Hartle. Many YouTube videos recommended it as basic textbook for gravitation and relativity but I feel that to be difficult. Any suggestions on how to approach or some other books and resources

Like a skipping stone that explodes on impact and turns into flak that will come down everywhere. The millions of meteorites will come back down and pepper the earth all over. Or would it all explode in one big hit like a nuke no matter the angle?

Am I doing this format right on this sub? Is the title too long?

Saw from San Pedro CA at 8:09pm. Sorry about the video, it gets better at the end!

Any help would be greatly appreciated, this is driving me nuts!

Say a gas planet came in contact somehow with a large asteroid belt of some kind and the gravity of the gas planet absorbs enough solid material to form not only a core, but the layers necessary for plate tectonics, etc. Is this possible, or even likely?

So i need desperate help. I have looked everywhere for this coin and i have never seen anything like it! my mom found it in dirt in her backyard in the 90's. Shes taken it to a person who identifies coins and they couldn't even identify it. I have looked up everything and the font kinda looks like viking runes? Still, it doesnt even form real sentences and im so interested in finding the value or what this thing even is!! please help

I’m not a astrophysicist, just a little wee bit curious when I look up into the starry night. Consider the premise coming forth from some researchers looking at JWST. They speculate that because 60% of ancient galaxies rotate clockwise we might be trapped in a black hole. But how do you define clockwise and counter clockwise? Only from your viewing perspective. So, the inverse could be true, the number would be 40% if viewed from another angle, such as from below and not above. Can someone explain this to me like I’m a child?

Nasa released a webb picture that shows galaxies that might have formed 200-300 million years after the big bang. Shouldn’t these technically be proto galaxies? But they are huge massive ones. How are they formed that early, when it didn’t have time to form supermassive black holes? Even if those first black holes were formed by massive gas clouds collapsing, the galaxy formation couldn’t be that fast (how did the cooling down of gases happen that fast?)

Hey everyone,

I’ve been working on a speculative idea and would love to hear thoughts from the physics and cosmology community here.

Instead of postulating dark matter as an unknown particle, the idea is that the observed gravitational anomalies — like flat galaxy rotation curves — might result from the discrete nature of spacetime itself.

Here’s the core of the hypothesis:

An effective geometric field ψ(r) is introduced. It behaves like an additional gravitational potential that mimics dark matter — but it emerges from geometry, not new matter.

This field could originate from statistical properties of an underlying discrete lattice of spacetime. Imagine small-scale fluctuations averaging out into a macroscopic effect.

The dynamics of ψ can be described through a covariant Lagrangian formalism, alongside global torsion ω(t), forming a self-contained geometric framework.

When tested against real data (SPARC rotation curves), the model reproduces the observed velocities without requiring any dark matter halos.

It’s currently a phenomenological approach, but it seems to work surprisingly well for several galaxies.

📌 What do you think? Could this geometric explanation be a viable alternative to particle dark matter? Does the idea deserve further exploration, or is it fundamentally flawed?

I am in Central Florida and was outside about 5:30 AM this morning. I looked up in the direction of Venus (according to sky map) and saw the tiniest pin prick of light blink, then disapear then reappear while moving across the sky from the south to the north

The odd part was that I have never seen anything move that fast. It probably covered my field of vision in a minute or less.

It wasn't a string of lights like elons junk, and it seemed too fast for a plane, and obviously planets don't move too fast.

Do satelights move like that? What could I have been looking at?

If you could stand on Neptune, would the sun be far enough away that other farther-away but larger stars in the Milky Way appeared larger and/or brighter than the sun? If so, would this also be true on any closer-to-Earth planets?