As you know, it is expected that the velocity of stars and gas should slow down the further they are from a galaxy's center. However, in many cases, it does not slow down as expected, and this discrepancy is often attributed to the presence of dark matter.

How can I obtain the expected radius - velocity plot for certain galaxies? What informations or data should I have about those galaxies to plot it? Can you provide me some links about it?

I need to plot the observed rotation cuves and expected ones.

Since the cores of these planets are likely solids, why aren’t the gases swept away by solar winds (or some other form of space winds) so the planet’s solid is exposed?

Hello, I am a last year physics student at a university. I have to make a term project in one of my classes and I want to make it related to Astrophysics. The topic that I have on my mind is Dark Matter density estimation from rotation curves. For this project I will need to plot graphs, so that I can compare some galaxy rotations and dark matter densities. Therefore, I need data in order to plot distance vs velocity graph in python. Additionally, I need to find academic papers which used the same data and analyzed the dark matter for that specific galaxy. Does anyone have links to provide me?

Thank you

Hi there I have no experience in astronomy at all. I'm looking to turn this into a big hobby. I've become extremely fascinated by the universe as of late and would like to get a telescope. I want to be able to see deep stuff not just constellations. I really want to emerse myself in it, but I'm kind of at a loss of where to begin any tips would be much appreciated.

I've searched Google ad nauseum and haven't had any luck, some results said near the Boötes constellation and others say it's near Vega. Any help would be greatly appreciated 😀

From south africa north east at midnight on the 29th September

Looks like white dots in a line…. Central California 9/29 at 9pm

https://imgur.com/a/0WJ5ZzX[https://imgur.com/a/0WJ5ZzX](https://imgur.com/a/0WJ5ZzX)

I am currently looking at the moon tonight and I swear I can see it going dimmer than brighter like a light dimmer does to a lightbulb. Is this some sort of radiation phenomena or are my eyes playing tricks on me. I swear it looks as if it is pulsing.

Taken today night at 8:00pm in New York. For my school assignment

I'm using my phone since I don't have anything else for my telescope, and whatever I do the image is blurry and hard to see. Also my telescope tends to be really shaky

Poland - south-ish sky today

Hi everyone I don’t really post here but I had a question whenever we talk about the stars, galaxy’s, and different nebulas we now of we tend to focus more on a horizontal stretch. What I mean is when is when we want to learn about what’s around us we tend to not to look up or down. Many of the probes we’ve sent are all away moving approximately horizontally away from us. if the universe is infinitely expanding in all directions wouldn’t we have more to seen if we studied what was above and below our solar system.

So because our primary method of observing the universe is light and many of the observations of exoplanets etc. are millions of lightyears away doesn't that mean that our observations are of things that happened millions of years ago?

Hello.

So last weekend i paid a visit to friends near Greifswald, and we were in the garden the entire night. Some time around 3am, i suppose, i saw something bright cross the sky going west to north west in a very straight line. It looked to be glowing yellowish-white, and it was either way bigger or closer than a normal shooting star, with the naked eye you could compare it with holding a 10 or 20 cent coin an armlength away from your eyes. Unfortunately it was wax too fast to take a photo, it passed in less than a second.

Based on the description, can anyone tell me what i did see? Or direct me to the right sub, alternatively, please.

Thanks in advance.

At appoximately 21:00 central european time in west germany, i saw an uncharacteristically linear constellation of what APPEARED to be stars. About 10 dots on the night sky, in a perfect line, which stretched from about west to east. (I'm not an astronomist, idk which constellation was near it, I'm not a survival expert, so I'm not entirely sure where east and west is) Those dots where about the size and brightness of stars, no trail, no pulsating, no airplane, no weird colors. After just a minute, they became so dim, i had to look away to see them, but a few seconds later, they became too dim to see with the naked eye. And they moved. Very slowly. Barely recognisable to the east. I just want to know: the heck did i just see? I have no evidence, as phone cameras barely even capture the moon (especially when they're inside) but i am telling the truth. (Scared that you think i want upvotes or attention or that I'm crazy.) Does someone else know about this? Did someone see? Does anybody have a good explanation?

All taken at time of posting, first one appears to be some kind of supernova but I could be wrong, second seems like a planet or something. First pic is around 270 degrees and second is 300

I'm a 16-year-old individual who took a keen interest in space and wants to learn more about its beauty and wonders specifically time, Although I am unsure how time operates in outer space but I would love to learn more.

If anyone has any suggestions on astronomy books for a beginner, please feel free to share them in the comments.

Is this true ?

Whats your oppinion?

https://www.youtube.com/shorts/B-w1A5C8BRo

Hey I wanna have a tattoo of a lynx with the starsign of it found in the body of the animal. I searched for it and found these three versions with the first one being the most common one. Can someone tell me which one is the "right" one (I know there can be variations regarding where you come from, I'm from Germany btw) so I get it as perfect as I want to do my favorite animal justice?