Astronomy and Cosmology

BH's by there very nature can never be seen directly, but their existence is near certain. If we are to deny the existence of BH's we must then explain in some other way the incredible effects on space and matter energy within their vicinity. see also....https://www.scienceforums.net/topic/117001-on-the-existence-of-black-holes/

I'm sure many will be interested in this article and the facts presented supporting GR as the current accepted and evidenced gravitational theory, that has passed all tests and made successful predictions. It appears it will be that way for a long time yet, as we are no closer to be able to formulate any QGT that can be validated.Despite my valuable time taken in presenting the following, I see it as necessary taking into account the many unscientific, unprofessional online criticisms of GR and the great man, by a diverse collection of lay people.https://phys.org/news/2018-01-gravitational-universe.html#jCpGravitational waves measure the universeJanuary 8, 2018, Harvard-S…

Recently in another thread on Philosophy, I had cause to question a claim made that BH's have been shown not to exist. Reasons were because Hawking Radiation had not been discovered and the Information/Firewall paradox. I replied how whether HR existed or not and irrespective of any information paradox, that BH's were well supported by evidence to exist and that the claims made were wrong and invalid. The person who denied their existence I'm sure was not really attuned to the history of BH's or any of the facts, and probably had only heard/read about them in a few pop science coverages in the daily media. His mispelling of Stephen Hawking's name as Hawkins lead me …

Hi All, I am trying to understand how we can show that the expansion of the universe is accelerating. I understand that one way is to use data taken from observing Type 1a supernovae due to their standard intrinsic luminosity. This then allows us to calculate luminosity distance and redshift, and from there calculate a ratio that apparently shows it to be non-linear over many samples taken at large distances. Wouldn't this just show that the expansion rate is changing? How do we specifically know it is accelerating? Have we ever observed a ratio that suggests the opposite? What I also do not understand is how we can know what the size of the universe was a…

Hi, sorry if you see any mistakes, its not my mother language i have a theory came to my mind about gravity if super massive star have huge amount of gravity, thats what we know it explodes, and loose around 95% of her mass, doesnt mean that core mass should weaken? that means the gravity it self is not affected by star, it affected by the matter in space and star forms, on gravitational “hole” on that place then all around it makes sense, because after supernova it should loose mass, not become a black hole what you guys think about it?

Hello, I see video’s about exoplanets around different stars, and there are also stars that can become trillions of years? I would like to know more about such stars as also: Since when is it known that there are stars that can become trillions of years?

https://www.businessinsider.com.au/elon-musk-spacex-mars-plan-timeline-2018-10?r=US&IR=T Elon Musk is hell-bent on colonizing Mars. That’s the spirit with which he founded SpaceX, his rocket company, in 2002. Musk was frustrated that NASA wasn’t doing more to get people to the red planet – and concerned a backup plan for humanity wasn’t being developed (for when Earth becomes an uninhabitablewasteland). Since then, SpaceX has developed several impressive aerospace systems: Falcon 1, SpaceX’s first orbital rocket; Grasshopper, a small self-landing test rocket; Falcon 9, a reusable orbital-class launcher; Dragona, a spaceship for cargo and soon NASA astro…

A thing that I want to know, using this topic which comes to this subject, is: If in a singularity, the time passes so slowly that for us (out of it) it would be infinite (since the singularity has infinite density) how can we observe the effects of the black hole angular momentum? (if you don't understand something, please ask me, my english isn't good)

A hologram works by having the whole image embedded in every part. In games programming there is a similar idea called 'tile based worlds'. For example, to create a chess board you create a single tile with all possible combinations then just repeat it 64 times. Is it worthy idea, an innovation, in applying these principles to the physics of the universe, or has someone already done this? Just for example, saying the universe is composed of mini-universes that just go through a big bang/heat death cycle billions of times a second, creating not the whole universe but just a small part.

https://phys.org/news/2018-10-aussie-telescope-mysterious-fast-radio.html Aussie telescope almost doubles known number of mysterious 'fast radio bursts' October 10, 2018, International Centre for Radio Astronomy Research Australian researchers using a CSIRO radio telescope in Western Australia have nearly doubled the known number of 'fast radio bursts'— powerful flashes of radio waves from deep space. The team's discoveries include the closest and brightest fast radio bursts ever detected. Their findings were reported today in the journal Nature. Fast radio bursts come from all over the sky and last for just milliseconds. Scientists …

https://phys.org/news/2018-10-nasa-humans-venus-brilliant-idea.html NASA wants to send humans to Venus – here's why that's a brilliant idea October 16, 2018 by Gareth Dorrian And Ian Whittaker, The Conversation Credit: NASA extracts: Hovering in the atmosphere .I'm all for it! One of the apparent dangers was that Venus's atmosphere is acidic with H2SO4 [Sulphuric acid] falling as rain. This is readily overcome and to quote the article again, They had in excess of 200,000 applicants for Bas Landorp's one way Mars trip, I'm pretty sure they'll get at least that number here. What do others think? My greatest wish again is that…

Some sad from NASA this week is that the Chandra X-Ray Observatory is dead. On Friday, Oct. 12, 2018, the space agency said that the telescope automatically went into so-called safe mode. Also the HST went into hibernation last Friday 5th due to a gyroscope failure. Yet Voyager 2 is nearing the edge of the heliosphere, which Voyager 1 has already left. Obviously everything has a "use by date" but did we make things better 40 years ago? The Mars Opportunity Rover I suppose is an exception as is probably the Curiosity Rover. Probable reasons I would imagine is that the HST simply has more intricate parts, such as its gyroscopes and mirrors...So what other reasons facts w…

If gravitational radiation is traveling, then in space is more and more the meetting gravitational radiation. Does it increase quantity of meters of the space?

I am keen to get the answer as to what is the Difference between gas composition of nebulae and gas planets like jupiter. Why doesn't jupiter explode or create stars like nebulae do. Do nebulae have something else going that gives birth to stars.

Hello, was trying to find information about long term star observation, but google giving so many garbage. Please give me direction where to finde some info about magnetic pole flips of closest stars (not sun). Best regards Dynin A.I.

Hi, I'm just wondering how the big bang could have happened if there was nothing before it in the first place? what I'm told happened was this below that is bold and underlined. The current leading theory states that the universe expanded incredibly rapidly in a very very short space of time, due to a process called cosmic inflation. This theory made some predictions which have since been borne out, eg by some features of the cosmic background radiation, and so it’s a strong, widely accepted theory. That begs the question “Well, what inflated?”, and that is a good question. We’re not quite sure. But, it seems that there was something there before, that dumped a great…

https://phys.org/news/2018-10-early-universe-fluid-quark-gluon-plasma.html The early universe was a fluid quark-gluon plasma: Scientists from the Niels Bohr Institute, University of Copenhagen, and their colleagues from the international ALICE collaboration recently collided xenon nuclei, in order to gain new insights into the properties of the Quark-Gluon Plasma (the QGP) – the matter that the universe consisted of up to a microsecond after the Big Bang. The QGP, as the name suggests, is a special state consisting of the fundamental particles, the quarks, and the particles that bind the quarks together, the gluons. The result was obtained using the ALICE experi…

Spoiler Or at least show me what part seems wrong to you. please. May i ask your opinon on another thing. it is about black hole and dark matter.How i see a black hoel and galaxy around itall galaxy objects like asteroind, planets stars have a layer like stracture.Most likely black hole too. As i see it lairs is 1C-2C-3C-4C-5C-6C divided be speed of light (particles found in big colider most like particles from first lair, they stable there, stable at high speed/pressure),the deeper the heavier. (lairs example-lie earth or sun lairs havier to center push lighter up top)Particles constantly fusion and diffusion.example of dark m…

Please note this is rather speculative… I was wondering about information. Is it reasonable to regard the position of particles as information about the volume of space containing the particles? If yes, then there seems to be a simple argument for space being discrete: - Assume space is continuous - Implies particles have infinite positional precision. We might not be able to measure with infinite precision; but the underlying system is continuous so possesses infinite precision - So there is an infinite amount of information in a spacial volume of 1 cubic unit - And there is also an infinite amount of information in a spacial volume of 100…

https://en.wikipedia.org/wiki/Measure_problem_(cosmology) Two beaded cows as likely as one headed cows? A paradox surely. Paradoxes are indicative of an underlying logic error. In the case of the measure problem, it is probability that fails us. Why? Because we are plugging in the Actually Infinite as a real number. The Actually Infinite is an illogical concept that does not exist mathematically or in the material world. Infinity is defined in maths in two major ways: - Calculus. The limit concept. Tending to but never reaching Actual Infinity - Set theory. Actual completed infinite sets are allowed, IE Actual Infinity. How is Actual…

Ok, so we have all this evidence and models for the big bang. Do these models, using the same logic that got us from the beginning to now to get us from now till the end, accuratly predict the fate of the universe?

Why is it only things of small scale that experience loss of energy relative to the universe size. Heck even the universe is expanding.

I see the examples of gravity as the bending of spacetime with a planet orbiting the sun. But how does that work for the gravity that keeps me on the surface of the earth?

Logic is the art and science of reasoning, does the universe have reasons (logic) behind it existence? This is probably in the wrong category, I am still getting use to the forums.

https://phys.org/news/2018-09-gravitational-dose-reality-extra-dimensions.html Gravitational waves provide dose of reality about extra dimensions: September 14, 2018 by Louise Lerner, University of Chicago: While last year's discovery of gravitational waves from colliding neutron stars was earth-shaking, it won't add extra dimensions to our understanding of the universe—not literal ones, at least. University of Chicago astronomers found no evidence for extra spatial dimensions to the universe based on the gravitational wave data. Their research, published in the Journal of Cosmology and Astroparticle Physics, is one of many papers in the wake of th…