Astronomy and Cosmology

Why is it not just E=mc? Why is the equation Squared?

In about 4 billion years, these two spiral galaxies will merge together to form one big, much more massive, elliptical galaxy. How will other galaxies in the universe react to this (gravitationally)? Are there any other big collisions scheduled to occur?

Does the law of conservation of energy mean that all photons and matter particles that exist in the universe right now have, in one form or another, always been around from the Big Bang on (only closer), and there will never be an increase in the amount of energy/mass? Doesn’t dark energy contradict the law of conservation of energy?

https://www.ligo.caltech.edu/WA/news/ligo20171115 Scientists searching for gravitational waves have confirmed yet another detection from their fruitful observing run earlier this year. Dubbed GW170608, the latest discovery was produced by the merger of two relatively light black holes, 7 and 12 times the mass of the sun, at a distance of about a billion light-years from Earth. The merger left behind a final black hole 18 times the mass of the sun, meaning that energy equivalent to about 1 solar mass was emitted as gravitational waves during the collision. more at link....

A new study finds a very calm and defined spiral galaxy 11 billion years old: http://zeenews.india.com/space/scientists-discover-most-ancient-spiral-galaxy-2054481.html. Does this finding present a challenge to the 13.8 billion year age of the universe in terms of the general view that it takes far longer for this kind of spiral galaxy to form through normal gravitational processes?

I would be grateful in some review of the following paper could be given by those with the required level of expertise on the subject. I believe in this day and age, after recent observational discoveries that BHs are pretty well beyond doubt. Not though according to this paper and its initiator. Would those that are able to invalidate his concepts in the paper, mind if I transpose their answers to the person concerned and in that forum? Your name and handle of course will not be used, just your reply. Thanks to all taking the time to review this...much appreciated. https://www.academia.edu/34549343/Gravity_causes_release_of_Energy_in_Neutron_Star Grav…

We seem to have a lot of 'evidence' of the universe being 13.8 billion years old, with some people believing it could be younger. Are we talking about the age of the matter in the universe, or the age of the Universe. When the BB occurred time did not exist. Time began some period after BB but the Universe came into existence as BB occurred. If the originating stuff that created(?) BB was spinning then the universe would not be spherical. Possibly like a spiral? Or even donut shaped. Or could it be spherical but with an area of nothingness surrounding the place where the BB originated as all the matter was ejected? I'm being devils advocate to start …

https://phys.org/news/2017-11-star-survived-years.html Star exploded, survived, and exploded again more than 50 years later November 8, 2017 It's the celestial equivalent of a horror movie villain—a star that wouldn't stay dead. An international team of astronomers including Carnegie's Nick Konidaris and Benjamin Shappee discovered a star that exploded multiple times over a period of 50 years. The finding, published by Nature, completely confounds existing knowledge of a star's end of life, and Konidaris' instrument-construction played a crucial role in analyzing the phenomenon. In September 2014, the intermediate Palomar Transient Factory team of…

Though we all know that Halton Arp gets no respect among mainstream cosmologists, despite his background and pedigree working with Hubble, I'd like to know if anyone here can help with debunking or supporting one of Arp's key arguments for a very different kind of cosmology. In his 2003 book, Seeing Red, he describes strings of galaxies and related objects in both Virgo and Fornax with anomalous redshifts, but anomalous in a patterned way that suggested to him that the central galaxy in each string was a parent galaxy that ejected the higher z value galaxies to each side in pairs that then disperse over time and give birth to their own galaxies. I know this sounds very we…

I am trying to figure out how these forms of matter are supposed to work but I can't even figure out why we know about them or think we do. I do understand that galaxies appear to be moving away faster than expected but I don't understand why that's relevant. Any good reading on the matter (ahem) that a lay-person could understand?

A new video animation of dwarf planet Ceres, based on images taken by NASA's Dawn spacecraft, provides dramatic flyover views of this heavily cratered, mysterious world. The images come from Dawn's first mapping orbit at Ceres, at an altitude of 8,400 mile (13,600 kilometers), as well as navigational images taken from 3,200 miles (5,100 kilometers) away. The images provided information for a three-dimensional terrain model. The vertical dimension has been exaggerated by a factor of two, and a star field has been added in the background. Any discussions and/or peer reviews about this specific topic thread? Fly over dwarf planet Ceres: https://www.youtube.com/embed…

How can a sound wave propagate in the near vacuum of celestial space?

Modern astronomers use parallax to determine the distance to a star. Parallax is based on the stars of the stellar universe that are stationary where the change in the angular position of a stationary star is measured after the observed on the earth propagates the distance of the earth's orbital diameter (six months) but the distance to a 4.22 light year (4 x 10^16 meters) star is more than 10^7 times larger than the earth's orbital diameter (1.4 x 10^10 m); consequently, the parallax reference distance of the earth's orbital distance is to short of a distance to produce a change in the angular position of a stationary 4.22 ly star using the Hubble that has a resolution o…

Is there anything unexpected that could arise from 2 BHs colliding at speed? Would this just be another form of a Black Hole merger or would this be a (obviously just a thought experiment) way of breaking up the Black Holes and liberating what has accumulated inside ? I realize the concept seems ridiculous (I actually hit the submit button too soon and by mistake and so had to continue with the post) but what is the answer (can it be said?)

ESTIMATE THE SIZE OF OUR UNIVERSE USING DATA FROM COSMIC EVENTS.pdf ESTIMATE THE SIZE OF OUR UNIVERSE USING DATA FROM COSMIC EVENTS Assumptions: 1. Our 3-D universe is on the surface of a 4-D globe. 2. Gravitational wave travels within the 4-D globe at speed of light. 3. Gamma-ray, as well as other electromagnetic waves, travels along the surface of the 4-D globe. As illustrated above, X is the distance of the cosmic event; R is the radius of our 4-D globe; C is speed of light; t is the time difference between detection of gravitational wave and gamma-ray. X – 2R*sin(X/2R) = C*t On 8/17/2017, gravitational …

Does a binary black hole merger have an em signal? Might this latest observation bring closer capturing a binary black hole merger using that em or optical signal?

There are things about cosmology that I just don't understand! Microwave Background Radiation is one of them. We are told that this is an extremely uniform residual from the Big Bang and that it indicates that the early universe (before stars formed) was extremely uniform. How can it be as uniform as reported, don’t stars, galaxies and even planets (like Jupiter) emit radiation in the microwave band? Wouldn’t microwave radiation emitted by the Big Bang at the time traveled far beyond us ages ago??? If they are talking about a “current” (more or less) afterglow from the universe, i.e. thinking of the entire universe as a Black Body Radiator as it has cooled since the …

The Chelyabinsk meteor has been suggested as an example of the potential of asteroids not being detected until just prior to impacting or grazing the earth. In this case, it was - to quote a Business Insider article in 2013 - "... because it came out of the daytime sky. These are nearly impossible to find ahead of time because telescopes can only spot asteroids during the night." (quoted from http://www.businessinsider.com/heres-why-astronomers-did-not-detect-the-russia-meteor-ahead-of-time-2013-2). First, is this article's claim about the daytime sky as accurate as the article suggests? My primary question, related to this, is whether or not it would be possib…

This question was raised in another thread (where it was considered off topic) There is no obvious relation between them. To quote from Katie Mack's FAQ: http://www.astrokatie.com/faq/#DMDE

Hi. The question above arises out of things like "The universe is 13 trillion years old." The assumption seems to be that everyone experiences time at the same rate, even though we know this isn't true. Relativity posits that as anyone accelerates, time slows down. GPS satellites have to take this skew into account to even work. So why does this get ignored in cosmological models? Consider the following thought experiment. I get in a spaceship that can accelerate to any speed less than c. It stands to reason that such a craft could go fast enough that its clock would only move 1 year in the time that the vessel went from here to the nearest star. Yet, as it look…

https://phys.org/news/2017-10-teams-astronomers-evidence-baryonic.html (Phys.org)—Two teams working independently have found evidence of the existence of Baryonic matter—particles that link galaxies together. One team was made of members from the Institute of Space Astrophysics, the other was based out of the University of Edinburgh. Both teams have uploaded a paper describing their work to the arXiv preprint server and both are claiming their findings solve the mystery of where so much of the normal matter—protons, neutrons and electrons—in the universe has been hiding. Once scientists came up with the Big Bang Theory, a problem immediately arose—after calculat…

The degradation in the orbital parameters of the Hulse/Taylor binary system was our first indication of the validity of GWs: A while ago on another forum, while discussing this observation, the claim that this observation was fraudulent was raised by one of our anti science god bothering evangelists, who claimed that the orbital degradation was simply a result of the interaction/s of the magnetic fields of these Pulsars. I'm pretty sure that this scenario would have been allowed for, and probably the effect from interacting magnetic field/s as minimal if at all. Does anyone have any information as to what part magnetic fields would play, if they did play a part, and …

NASA Aftermath of the Chelyabinsk Meteor https://www.youtube.com/watch?v=Q9KwK0izt5c Now imagine what happens if it is meteor with organic compounds, DNA/RNA, or even microorganisms.. They're spread on the entire planet, like this has been shown on the video, within couple days. On the raw planet, new life will appear the first time, but on planet with living lifeforms, it can have devastating consequences, and destruction of existing lifeforms and replacing them by newly arrived microorganisms.

Hey everyone, So, we know black hole has a singularity in middle of itself and it has infinite mass and no volume. But why we saying that? And if it has infinite mass on one point why it doesn't have infinite gravity? If so, why not everything going inside it?

It's known that all galaxies are moving away faster from each other, due to dark energy. The further away these galaxies are from each other, the faster their movement is. Newton's law of motion (which is about gravity of course, not dark energy) states that, on earth, a falling object will accelerate, but, after a while this acceleration stops, due to its mass, and a steady falling speed remains without any further acceleration. Again, this is gravity, not dark energy, so why this example? Well, I'm wondering if it has yet been detected that galaxies far away from us (outside our Local Group, to exclude a gravitationally bound galaxy like Andromeda) have decre…