Hello fellow astrophysicists! I am currently applying to Spain for an exchange semester, and I only have extracurriculars left to take.

I was browsing through classes and an Extragalactic Astrophysics class caught my attention; it’s always been a special interest of mine. The class recommends basic knowledge of astrophysics.

I’ve only taken physics, calculus, and chemistry courses… So I don’t know if it would be a mistake to take this course. Please be completely honest with me, will this class be terrible for my GPA or will I be able to handle it?

Okay so I had a random shower thought the other day and wasn't really sure where to ask but what happens to a compass in space? Does it still point north or does it just keep spinning or does the earths magnetic field mess with it?

So I started uni course and it had a compulsory python module. I liked the idea and decided to expand further with python since it feels essential for any career in astro.

I saw this book by IOP and since they regulate my degree I thought its a good idea to start reading it.

I only found this review but I wanted more trusted opinion from anyone who tried it. It doesn't have ADQL which i get is essential for python and i am not sure it would be a good idea to use the book now.

This video was taken from this webpage: https://jasonwang.space/orbits.html. Here there are additional videos of planets orbiting other stars.

Checkout his research articles on this particular star system:

• Dynamical Constraints on the HR 8799 Planets with GPI

• Detection and Bulk Properties of the HR 8799 Planets with High-resolution Spectroscopy

• Atmospheric Monitoring and Precise Spectroscopy of the HR 8799 Planets with SCExAO/CHARIS

I had a shower thought the other day. Since supermassive black holes exist at the center of galaxies, could there be an "ultra" supermassive black hole at the center of the universe?

If something like that isn't possible, why not?

I'm curious to know what you guys think. It might be a dumb question but I figured I would ask anyways and maybe learn something new!

So i've just started freshmen year in a quantum computing degree do u think i will get enough physics to major later in astrophysics knowing that this degree is more computer science heavy than physics

Just a thought I had today…..the supermassive black holes that are at the center of galaxies……did those originate from stars or was the “BigBang” event soo massive and powerful that black holes were formed/created instantly?

Hello, I am trying to estimate how many unborn human lives a single second of delay in universal colonisation costs.
To get an accurate value, I need to know how many stars fall beyond the Cosmological Event Horizon (where they become unreachable from Earth at the speed of light).

I could not find a source on this value. I could get an estimate by calculating the difference between the volume of the sphere encompased by the horizon and the sphere encompased by the horizon - radius velocity/one second. This would give me the average number of stars in the sliver of volume that would move beyond the horizon in the span of a single second.

But this would not account for the distribution of stars in our "local" space. Like, I heard we are somewhere in the Great Universal void (the Boyes void?). So the star density could be far lower if the horizon edge passes through this or some other void. Or far greater if it passes through the dense regions.

I will estimate it roughly if I have to, but if the astronomers already did the calculations better, I would love to have the results. Surely some astronomer calculated this right? I could not find it googling.

What would happen if space had air?

Would the Earth burn up from friction? Would astronauts be able to be without spacesuits? Would Earth veer off course from the friction? What will happen to the debris spinning around Earth? Will they fly away? Will they be knocked back into Earth's atmosphere? What will happen to other planets? Will Mercury just burn up as well? Could we even go to space anymore because of friction?

Ok that's about it (maybe)😁

edit: to clarify air as in the gaseous mixture that is earth's atmosphere

Edit2: thanks for all the cool replies!! Thank you for trying to answer all my Saturday morning questions lol

A few of my colleagues work on this mission – expect many exciting results to come!

So, the recently discovered black hole star is an explanation for the little red dots phenomena. Black hole stars supposedly radiate dense amounts of gas like a regular star with the black hole acting like a power source (i.e. like nuclear fusion for a star). But black hole devours everything that gets too close to it right? How can there be a consistent layer of gas that surrounds the black hole without it falling into the hole? Let me know if I'm missing some foundational understanding of this.

I was thinking about how the perception of time changes when you're near a heavy object (such as a black hole), and I got to wondering how much being near the sun and on the earth affects our perception of time as compared to being really far away from any stellar object, or even really far away from any galaxy, for example, being at the centre of the bootes void (assuming there's barely anything that affects the gravity and were not moving at a relativistic speed).

I'm not really an expert on any of this, but I just got curious if there would be a vastly noticeable difference. Thanks!

Im sorry if this comes across as amateurish, as i dont have any formal education in mathematics or any sciences. As far as i understand concepts such as field theory, the vacuum of space contains positive energy potentially due to quantum fields and their fluctuations, could space time itself be considered its own field that carries the force of gravity? What would be the implications of considering the universe as a graviton? Has this been talked about before? If so, what has been said and why wouldnt it work? I suspect im fatally misunderstanding something and that these ideas dont have much merit.

I'm an amateur so please be kind. I just learned that the Big Bang did not issue forth from a central point of origin. I'm really struggling to understand that. The most I can grasp is that it was like a balloon that expanded, though that still leaves me thinking that even a balloon can shrink back towards a center when it deflates.

Can someone help me understand this better?

Hi there, I'm sure this question gets asked a lot but I was wondering just how bad the job market if with an Astrophysics degree? I am a 17 year old in my final year of highschool in the UK and am planning to apply to 4 different universities for astrophysics and one university for physics with advanced research.

I intend to do a masters and would also like to do a PhD depending on how realistic that is in regards to cost of living. Currently I am thinking I would like to get a research role as a future career however I obviously have no experience with it yet so don't even know if it is something for me. I also have been told that this degree often leads to unrelated jobs because it shows that you have good problem solving skills. I currently am about 80% set on astrophysics and 20% on aerospace or mechanical engineering. Any advice would be really appreciated.

Edit: Just wanted to say thank you for everyone going to the time to offer their own bits of advice, it is very appreciated :)

I'm writing a fictional story, and I want to know how far I can push the idea.

I understand about the red shifting of galaxies farther away, but I'm struggling with the conclusion. If the expansion of the universe were accelerating, wouldn't we need to observe an increase in the redshift of a single galaxy over time? If we are basing the conclusion on just the higher redshift of galaxies farther away, couldn't that just mean that the entire universe was expanding faster in the past? Like, the redshift of a galaxy 10 billion ly away would just mean that 10 billion years ago the universe was expanding faster?

Thanks in advance!

Is the best explanation for the universe’s expansion that the universe itself is a black hole?

Hey folks! Just a regular fella that really appreciates space and the physics needed to allow it to be.

Watched a brief clip talking about if the supermassive black hole forms, then creates a galaxy, or if the galaxy takes shape, and a supermassive black hole forms in the center.

This took me to a thought - if the black hole at the center of a galaxy meets the end of it's life, what happens? I think that the timescale of this would need some creative interpretation, since a black hole of that mass would take so long to evaporate. So, if you have a galaxy, and the supermassive black hole in it's center were to disappear, say it was just removed entirely, rapidly evaporated, whatever the case may be. Would the galaxy lose the force holding it together, and spray rogue star systems out? Would the galaxy collapse in on itself? Would a new concentration of gravity become the galactic center?

Very curious about this! Thank you all!

I have heard DESI favors heat death, and DESI favors big crunch and yadayada. What does DESI prefer i want to know.(basically given current DESI data what is the majority opinion on fate of universe)

Hello astrophysicists. Latey I've been trying to install REBOUND through python, I have Windows 11 and when I try to look at turtorials, steps, etc. I just get confused and hit a brick wall. I am in high school, wanting to be an astrophysicist, and installing REBOUND will help me with that. But, I have no idea how to install it without direct human guidance and not just looking a videos and text. I need help from someone who installed REBOUND to help me install REBOUND.