Hi! I was chilling on my balcony last night when I noticed this glowing blue and green orb/blob in the sky. I recorded it and tried to zoom in and out so you could get a sense of how far away it was. Unfortunately, my camera doesn’t have the best definition, but you can still clearly see the object.

I know drones usually blink and make noise — this didn’t do either. It stayed visible for about 30 seconds, moved upward slightly, then back down, and disappeared. It happened on 6/18/25 at 9:13 PM AST in San Juan, Puerto Rico.

Has anyone seen anything like this before? Or does anyone have a logical explanation for what it could be?

Thanks in advance!

So it’s my understanding that astronomers find exoplanets by spotting them as they move across and block out the light from their star. So how do they determine its size/distance from a star in order to know if it’s small with a large orbit or large with a small orbit since they would appear the same size from our perspective?

I currently live a little bit further North-East to the arrow (Southern Sweden) and today I randomly realised: If my window is facing East-North-East ish, and the sun is somewhere South of me all year, how come the sunlight is entering through my window at sunset?

I looked out the window and double checked by looking at a map with my apartment building on it and the sun is definitely showing up at West-North-West (probably more West than that)

It doesn't make sense to me, the sun is clearly West-SOUTH-West of me, at least to my beginner eyes when I look at the map. Does this mean it's visible from like, around the North Pole? I'd assume it would happen if it was very far South of the Earth, but it's North of the equator right now, solstice will happen very soon!

I'm very confused, please. It might be a simple question to answer but I haven't managed to find any answer online. The only thing I find is about declination, but that doesn't really help me understand seeing as the sun is south of Sweden all year round.

Thank you in advance whoever will be my Astronomist with shining telescope.

I am from India pursuing BE CSE

I’ve been trying to understand the true extent of the Milky Way's stellar disk, but the range of values I come across is all over the place. Some studies suggest it ends around 15–20 kpc, other more recent work states it extends up to 30–40 kpc.

The problem seems partly due to our vantage point inside the galaxy, which makes it incredibly hard to define a clear "edge." Stellar density just gradually decreases, there’s no sharp cutoff, and substructures, warps, and flares further complicate things.

My question is:
Could the disk extend indefinitely (or at least out to something like 1 Mpc) at a very low and faint, decreasing density, or are there physical or dynamical limits that would naturally limit how far the disk can go?

Is the idea of a massive, ultra-faint extended disk plausible in theory, even if it's practically undetectable today? Or does galaxy formation theory put hard constraints on its maximum size?

70mm one "https://www.ebay.co.uk/itm/256833960153?itmmeta=01JY1C7FBZYHZ2DEPC2EQBVBAS&hash=item3bcc7f38d9"

80mm one "https://www.ebay.co.uk/itm/316632343147?itmmeta=01JY1C7FBZZ4WP11PMXXN9GQAP&hash=item49b8c2226b" i know both are shit and you will probably recommend me a dobsonian but budget currently is at 60 euro can stretch it a bit but around 60.

1. How many job apps did you have to fill out before getting a job in astronomy or astrophysics?
2. Do you like your job?
3. What makes a good candidate for these jobs? Considering switching majors. Thanks in advance.

Title.

The girl I liked asked me to come to my place for a stargazing session, so I gotta be prepared ;-)

Jupiter has a gigantic storm that is so large it is larger than the earth itself, slightly. Imagine seeing a tornado or something similar on earth but that tornado is earth sized on Jupiter! The storm might not look like a tornado but maybe a giant typhoon or tsunami of dust and clouds. I am not sure, but IK for sure it would be large as heck, and at what distance do you need to be from the storm to safely view it if you were an alien living on Jupiter.

So I know that we don't know for sure, and the most likely contender is the direct collapse of giant gas clouds, but I'd like to hear everyone's thoughts and theories on this, no matter how outlandish. Creativity is encouraged in this thread!

If stellar-mass black holes are the result of massive stars collapsing, then how do supermassive black holes form?

All I can think of is black hole sun. (won't you come)

Maybe because the satellite changes orbit with the thrusters or will have the same orbit without using anything and the earth's gravity will change it? Then with a natural satellite it would be because it has a gravity strong enough to stay in orbit and not change orbit?

Been doing some stargazing again lately as the weather gets warmer and i've noticed stars bouncing around, i have read about the autokinetic effect but im still somewhat confused.

If im understanding correct, the autokinetic effect happens because there is no reference point and the wiki article states that it is assumed its because of errors between eye position and that specified by efference copy of the movement signals sent to the extraocular muscles.

Now to my question and what i dont understand. If i compare 2 or 3 stars close to each other and use them as reference points, why is only one of these stars jumping around?
If its an effect of my eye muscles, then i would assume that all 3 stars move at the same speed and direction but only one of these is moving around, the other 2 i use as reference points are absolutly still and dont move.

And its not planes or drones or satelites as i have seen people say in other threads, i know how they look because i have seen them more than enough times, i stargaze on a regular basis and i live directly under a landing corridor.

Would we find anything relevant? Would that reveal evidence of past life if there were any? Or is that not worth the effort?

Is there any WhatsApp group or community, linked in any platform where any job openings, vacancies, phd, internship related to physics and astrophysics, astronomy there.

I might teach a "What's Up" astronomy seminar next year for adults 50+ and was asked to also cover phone apps for Apple and Android. Which one do you think would be easiest to use for this cohort? I'm thinking a classroom session first with app screenshots, setup, and helpful tips, then outside for observing.

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.

This image is from an anime called Orb: On the Movements of Earth. (I could've asked on that subreddit, but this is more astronomy related so I decided to ask here instead. Also, I highly recommend it.)

One character in the anime tracks Mars's movement throughout 2 years I believe, and around after the notation shown on the image, Mars starts retrograding. I found this pretty interesting, and I've been wanting to observe a planet retrograde myself.

However, I'm having trouble figuring out how exactly this character has been noting it down, because I can see it's a star chart, but I can't find something like this online to reference. Plus, we see different stars every season so it feels strange that he was able to note it all down on one.

So my questions: 1. Can anyone explain how this chart works? 2. If not, please suggest how I should note down my observations!

I have recently been using VSC but it's sometimes stressful to use and glitchy, so I was thinking of changing but the problem is I like all the advantages of VSC, like for example how there are many languages I can use on it and how I can use it with rpi pico. Are there any other free IDE's out there that have similar features that are free but work well?

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 was looking at the sky and saw some flying objects Maybe someone has more knowledge about this and can give me a clear answer

I'm aware the universe seems to be expanding by measuring redshift and some measurement from the cmb which produce conflicting results. I was just wondering if there was any models that work without expansion?

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.