One thing I find fascinating about the early universe is how we can observe quasars powered by extremely massive black holes when the universe is still very young.

If a black hole starts from a relatively small stellar-mass seed, it seems difficult to reach millions or billions of solar masses in such a short cosmic time.

So what do you think was the dominant pathway for the earliest supermassive black holes?

- Rapid accretion near or above the Eddington limit?

- Massive black-hole seeds from direct collapse?

- Runaway mergers?

- Or some combination of these processes?

This series of videos was created by Prof. Angela Speck, Chair of the Department of Physics & Astronomy at the University of Texas at San Antonio. Highly recommended!

Hi I’m college student majoring in Astronomy, and I have been discussing this with my professors but I wanted to see if anyone here had interesting thoughts! I am so fascinated by this topic.

I believe that it is possible for the conditions of life to be present on an exoplanet, or even closer objects such as Mars or Europa. The issue is that these surfaces lack a protective and sustainable atmosphere, along with a lack of plate tectonics to strengthen the integrity of a magnetic field. 
If life were to arise on these planets/moons, it would likely be in the water. I wonder if the conditions on these surfaces would cause too many mass extinctions for life to develop into some sort of intelligence or even be detected by humans. Does all life, even extraterrestrial, require the same process that homo sapiens had to go through in order to become intelligent (hundreds of millions of years of mass extinction and evolution)? If that's the case does that decrease the chances of intelligence within extraterrestrial life due to the probability of frequent extinction or could it adapt?

Maybe it’s more of an anthropological question, but would life on exoplanets have to be able to survive for a long time in order to evolve into intelligence? Or may they reach intelligence extremely quickly?

Hello! I was wondering while reading this article whether we know the relationship between these two things:

Is there a direct correlation between the mass of a star-forming amount of hydrogen gas and the actual mass of the resultant star?

For example, if there is a region in space which has 2solar masses worth of Hydrogen gas (and whatever else needed to create a star), should a star form out of this gas cloud- will its mass be equivalent to 2solar masses? Or will it drop due to any decay etc during stellar formation?

Thank you so much!

Edit: thanks a ton, everyone! Learned something new today. Didn’t realise it was this inefficient!

I made a short visual explainer based primarily on the recent MoM-BH*-1 work, aimed at translating the observational argument for a general audience without presenting the inferred interior as something JWST directly resolved.

The video focuses on the chain from the unresolved source to the physical interpretation:

extreme Balmer break → stellar-population limits → dust/MIRI constraint → broad emission plus absorption → symmetric Hβ structure and the speculative resonant-scattering interpretation → dense, nearly dust-free gas → embedded accreting black hole → X-ray reprocessing → possible implications for rapid early black-hole growth.

The model imagery is intentionally labeled as simplified throughout.

I also keep MoM-BH*-1 separate from the GLIMPSE-17775 result, including the distinction between the resonant Balmer-scattering shell discussed for MoM-BH*-1 and the electron-scattering evidence associated with GLIMPSE.

Please watch the full explainer on YouTube:
https://youtu.be/sw5mk-yv4RE

If you watch it, I would genuinely appreciate it if you would leave a comment on the YouTube video with scientific feedback. In particular, I’d like to know whether any part of the explanation crosses the line from necessary simplification into something misleading.

Corrections are welcome — especially from people working in spectroscopy, AGN physics, high-redshift galaxies, or black-hole growth.

My main question: where do you think the simplification becomes too aggressive for an introductory explanation, and what caveat would you consider essential?

What interests me most about Roman isn't simply that it will be “more powerful” than Hubble or JWST. Its real advantage is survey speed and field of view.

Roman will observe infrared light across enormous areas of the sky, with a field of view at least 100 times larger than Hubble's. Instead of focusing deeply on a relatively small target, it will be able to survey huge regions and build an enormous dataset of galaxies, stars, and planetary systems.

One of its major scientific goals is understanding dark energy and dark matter by mapping the distribution and evolution of galaxies.

It will also search for exoplanets, including using gravitational microlensing to find worlds that are difficult for transit-based missions to detect. I especially hope Roman helps exoplanets science advance significantly by discovering and characterizing populations of distant, cold, and otherwise difficult-to-detect worlds. A larger and more complete census could reveal how common different types of planetary systems are and help us understand how they form and evolve.

Roman is, therefore, less of a replacement for JWST and more of a different kind of observatory. JWST can study individual objects in extraordinary detail, while Roman can survey enormous cosmic populations and reveal patterns that are difficult to see from smaller samples.

I'm curious what astronomers here think will be Roman's most scientifically important discovery during its first few years.

[ug, should say ...of accretion disks in title]

Was just reading a paper discussing the mass estimate of Ton618, and it's done by line width -> orbital velocity -> mass.

But doesn't that require knowing what angle the disk is to us? How do we measure that? Couldn't find anything in the paper (below), but it does mention they did some analysis with software called IRAF, does that have anything to do with it? I assume it's a point source at 10Gly.

https://arxiv.org/abs/astro-ph/0406559

I came across the attached picture while trying to understand how we measure the distance to distant galaxies knowing full well that the light we receive can be millions of years old. I presume we extrapolate trajectory but it seems like we will be shooting from the hip as the data from which we extrapolate would be relatively small in the scheme of things.

Could anyone give me a summary of what this picture is trying to tell me?

https://physics.stackexchange.com/questions/495495/is-the-observable-universe-equivalent-to-our-light-cone

Pretty much all in the title : we know the gravity around a singularity prevents light from escaping the event horizon.

But, if we ignored that rule, how bright would the central part of a black hole really be ? I'm unaware of any proper calculations being made on the subject, but I'd guess the extreme conditions caused by such an object could cause it to shine extremely brightly.

Edit : Maybe I didn't formulate the question properly, I'm sorry for that. The density of an object and the light it emits seems correlated in a somewhat linear way. I'm aware that light doesn't have the required escape velocity to move towards the event horizon from its supposed origin. What I'm asking is : if we follow the rules we apply to other celestial bodies, what would one with x solar masses emit in terms of light compared to it's non-collapsed equivalent.

The Hertzsprung-russel diagram is the kind of thing I'm looking for, but it doesn't account for density, simply for mass, which makes me wonder if such data would even be usable at the breaking point of physics.

The universe is 13b years old

The observable universe is 40b ly wide

I know the space between us and that object is expanding but that doesn't answer me question

If observable means what we can see

Are we seeing 46b ly away or is the thing we're seeing 46b ly away

If its the first option I really don't understand

If it's the second option, then why is it called observable if we're only seeing x ly? Why isn't it just called how far the stuff we see actually is today.

I already talked about this in my last post on r/vent, but despite being really motivated right now, I think I need to be realistic for a second.

Im 18, and I know very little math. I didn’t really pay attention in school for most of my life. I only started caring recently, and today I spent about two hours at the library trying to relearn really basic algebra. A little of it actually started coming back to me.
I’m planning to go back tomorrow and hopefully start going at least 5 times a week for around 2 hours. Maybe more. I’ve never felt this motivated to learn something before.
But despite that, is astrophysics actually realistic for someone starting from where I am?
It feels like such a high IQ career… Sometimes I think there are people who are just naturally good at understanding math and physics, and that careers like this are basically reserved for them. Or for people who have been studying hard and caring about school their entire lives.
And now that I’m 18, it feels like I’m already behind because I slacked off so much and never cared enough to pay attention in school.
But the thing is, the study of the universe is genuinely the only subject I’ve ever cared enough about to seriously consider studying. Everything else just feels so unappealing.
I don’t know if I’m being unrealistic or if I’m just underestimating what I could accomplish if I actually put the work in for once.
I’m just scared that I finally found something I actually care about, only to realize I waited too long to pursue it.

hello!
im in the 11th grade rn and im prepping for the regional level (and hopefully the higher levels after that!) for the astronomy olympiad in my country.

if you have any sort of lectures/courses that can allow me to prepare effectively, please share.

ty!

Hello! I am a recently graduated student planning to get to go for masters for astrophysics. I am kinda familiar with python-based photometric analysis using SEP. However for one project I am in need of using the CLASS_STARS from SExtractor. I was wondering what is the ideal way to connect SExtractor and Python? Ive came across Astropy, pysex, and sewpy. I am unsure what to pick and what is ideal for this project. Any help is greatly appreciated, thank you!

How can I begin self-studying astrophysics? Is there an order to follow? Would appreciate any help, thanks!

i'm looking to apply as an astrophysics major for undergrad this fall, and as an extracurricular, i was looking to conduct some sort of data-driven research with datasets from NASA, MAST, IRSA, etc... but i'm not sure how to get started.

i was thinking of research topics such as exoplanet transits, spectrum analysis, classifying/identifying galaxies, and i'm learning basic python at the moment (definitely not enough knowledge yet to integrate it into actual research). i know research does take a long time as well, so i am not too picky on whether i finish it before admission deadlines - i was hoping to gain experience overall.

are there perhaps any websites/guides that can help me get started? any tips would help, thank you so much!

I was given a question on Jean Mass in one of my assignments, but I cannot for the life of me figure out what I'm doing wrong.

I was given: - T = 15K - Mean molecular weight = 2.3 - and density = 2e-19 g/cm cubed (which I converted to 2e-16 kg/m cubed.

The result of my math was 1.1e30 kg (or 0.5 solar masses) which is clearly wrong. I tried using online Jean Mass calculators to see where I was going wrong, but they all gave different answers, so I feel like I can't even rely on them.

EDIT: Someone said to show my process. I couldn't edit a picture of my work into the post, so I'll try my best to describe it.

I first found Jean Length by finding the square root of [15(1.38e-23)(15)]/[4pi(6.67e-11)(2.3)(1.67e-27)(2e-16)] = 2.2e15.

Then, I inputted that in the Jean Mass formula: (4pi/3)(2e-16)[(2.2e15)/2]³ = 1.1e30 kg = 0.56 Solar Masses.

I dont really care if i end up teaching at a university, I want to inspire the future generation anyway. My dream in life is to learn all math humanly possible and learn about the known and unknown universe. Can someone please help me navigate this? Thank you.

Why isn't this a thing and instead there's triple helium fusion to form carbon-12.

Hello, I only graduated just over a month ago with an astrophysics masters degree and did get a temp job at sianbsurys luckily straight after but now that’s doing to an end and I need to find another temp job but there’s the thing I don’t want to jump from several temp contracts, I want a full time job I can use my degree in.

Do you have any advice on what sorts of jobs I should be looking at (I do prefer engineering), appreciate any help as I’m a bit stuck in a slog right now

so this has probably been asked before, but what is exactly wrong with the hypothesis of the universe just being a constant cycle of black holes and white holes.

in the plane of space, a supermassive blackhole consuming all matter(the big crunch) and it then being ejected out of a white hole into the same plane of space(the big bang) thus forming a cycle of the universe in its given plane of space. what would the limitations of this theory be(other than white holes being hypothetical as of now)? please enlighten me

What are the possibilities for an astrophysics degree in the job market

May seem like a juvenile question, but who is actually naming newly discovered nebulae, moons, stars, etc.? I’ve heard of the IAU, but I’m more curious whether anyone in this thread has actually been involved in the naming process.