Astronomy and Cosmology

Using just the physical constants; c, h, G and the rest mass of the electron, with simple ratios it is possible to predict, the average Astronomical Unit, the mass of the Sun, and the average velocity of any object orbiting the Sun at A.U. distance. These ratios allow for the formulation of a different type of gravitational equation which is specific for the solar system. There is nothing unique about the solar system, but, these ratios do predict exact values. Perhaps with in these calculations there will appear concepts which will allow for generalizations which would apply universally.

Rotation seems to be a fundamental attribute of many aspects of reality: from particles; to planets; to moons; to stars; to star systems; to galaxies. So why not the whole Universe ?

Does anyone know if a stellar-sized black hole could be located very near us? Is it possible one could be closer than 4 light years, but since they are hard to detect, we simply don't know? Or are we fairly certain there are none nearby?

"NASA's kepler mission has discovered a planet where two suns set across the horizone instead of one. The planet called kepler-16b is the most "tatooine like" planet yet found in our galaxy. Tatooine is the name of the luke skywalker's home world in science fiction movie star wars. In this case the planet is not found to be habitable. It is a cold world with gaseous surface, but like tatooine it cycles two stars. The parent star is smaller than our sun. One is 69% the mass of our sun and the other, only 20%. Kepler-16b orbits around both stars every 229 days similar to venus' 225 day orbit, but lies outside the system's habitable zone where liquid water could exist on…

Moti Milgrom carefully analyzed a statistically robust number of spiral and other galaxies plus many galactic clusters. He discovered a strange leveling of the galactic rotational velocity distribution. He found the same effect in almost all the galaxies he studied. The ones that did not have the effect may have not yet developed supermassive black holes in their cores or had not yet had time for Milgrom's hyperbolic black-hole galactic gravitational field effect to propagate all the way to the periphery and beyond. See url deleted sub-site MOND for a more detailed treatment. A caveat - I give a graphic of a whiteboard mathematical presentation of the MOND effect comp…

I wasn't sure but decided to post this anyway.It's an intriguing topic and a very unusual astronomy website. They claim to have discovered a gigantic mountain on dwarf Planet Pluto. Their discovery was apparently reported to the IAU. The images are consistent but how the hack did they achieve these results is my question ?! http://spacenow.com.br/pluto6.html

About expanding of universe someone give balloon model. some one says expanding of universe is not correct. Actually what happening? If it expanding then how it possible?

(1) I found a plot, of the (non-circular, eccentric) absolute space velocities (in the [math]\Pi, W, \Theta[/math] directions), of a sizeable sample, of Globular Clusters (GCs), orbiting our Milky Way Galaxy (MWG) (page 9) (2) I found a plot, of the (circular) space velocities, of a sizeable sample, of Molecular Clouds (MCs), rotating within the disk, of the MWG (figure 11) (1) + (2) I over-plotted all of the above, "like a stack of transparencies". Visually, the velocities of halo GCs, and disk MCs, match, quite closely (~200 km/s), beyond the galacto-centric orbital radius, of our star system (~8 kpc). However, the "inner disk" (r < Rsun) MCs, still revolvi…

I am curious, and if I am not posting in the correct section feel free to move the topic, but what happens to light after sight? I've googled as much as I can, and perhaps I didn't word it correctly in my search, but what happpens to light after contact with your eye? Perhaps the best way to explain my question would be to drop the E-bomb, but if E=mc^2, how much light is reflected, absorbed, transfered as heat, etc. after all is said and done, and you "see the light" is there anything leftover, and in what form? My thought on posting it here would be in the event of travel equal to or greater than the speed of light. I am trying to put together some ideas…

http://en.wikipedia....Volcanism_on_Io Would it be possible, through a combination of tidal heating, radioactive isotope decay, and the greenhouse effect, for a very large moon (like Titan) of a very distant planet (like Uranus or Neptune), to sustain earth-like temperatures and atmospheric pressure, as well as liquid water? How far out from the sun would this become infeasible? And, if feasible, how long could such a state exist, if sustained by an orbital resonance, as is the case with Io? A few million years? Billions?

The following comments concern Astronomy and Cosmology only. They are not speculative. The following comments are not my own personal opinion. They do not constitute my own original research. If one carefully reads the papers submitted to ArXiv astrophysics from after 1998, one sees that Saul Perlmutter's and Adam Riess's supernova research groups were not independent (as claimed) and that they were in serious communication. Perlmutter and Riess actually wrote a paper together. They say that the data that the two groups got regarding the distances to supernovae type 1a and other bright extremely distant objects was not concordant at first. In order to force the t…

Admit that some critics have some valid points. But other valid points have been made. There is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work. Many of the therapies of alternative cosmology really work too. Alan Guth made a giant contribution to modern cosmology. Singularities as point masses are cental to "inflation-like" solutions to the flatness and horizon problems which had vexed astrophysicists for years prior to Guth. If these paradoxes had been so simple that they could have been dismissed in a few sentences, they would have been. There have been numerous attempts to refi…

Hi guys im just curious as to why the big crunch is dismissed so much by top end scientists and physicist's. To me the logical outcome of the big bang is the big crunch, it works perfectly with the laws of physics i know of (namely gravity in so much as what goes up must come down). I believe scientists think the rate of inflation for our universe is increasing, which i would not deny for a second however it doesnt matter if it increasing now because at some point in time (billions even trillions of years time) there MUST be a cut off point, now im not being funny but our universe is not the monetary system so i dont want to hear about perceptual inflation, its just not t…

Every force needs a energy ? What is the energy source of gravity ? how is it made?

There are a few exceptions. For example, Venus has the longest day, although Mercury is the smallest planet (ever since Pluto got demoted). However, for the most part, large planets have short days. Planets that are farther from the sun have longer years. That makes sense... they have a much greater circumference to orbit around. But... you'd expect bigger planets to have longer days, for the exact same reason... more distance the top clouds have to go around. What exactly causes bigger planets to actually have shorter days?

Recently, mooey depicted the BB as not being an explosion, per se, which draws to mind combustion or nuclear fission or fusion. With the creation of quark gluon plasma in colliders, one is drawn to a belief that the BB was more of a release from pressure, though I suppose an explosive process is still possible. Since it is postulated that the intense vacuum from the vast, empty space enabled matter to spread at ftl speeds (which is still fairly hard to believe since we're talking about the speed of light) this would mean that space already existed. Do you think it's possible that all of this matter existed in the form of one supermassive "superstar" in a massive, empty…

just a question. If, and Ill use the hubble space telescope for my question, if the hubble can "see" objects out about 14 billion light years in a particular direction, and you spun the hubble around to the opposite direction and it can "see" objects about 14 billion light years wouldnt that make the universe 38 billion years old? If your point of reference was the object viewed by the hubble 14 billion light years away and you were viewing the earth from there and that was as far as you could see, the object in the opposite direction would still be another 14 billion light years away right? im just asking. Just a reference to the fact that if you drew a circle wi…

Would adding more mass to the planet to increase the gravity have any effect on the core? Would the increased gravity speed the rotation of the core and create a magnetic field?

Metals can cool the clouds, in the ISM, from which stars form. And, the properties of those clouds could be characteristic, of the outer envelopes, of stars: Indeed, for a given 'core operating power', and hence, ultimately, luminosity, more metals makes stars colder (redder), but bigger -- shifting the MS to the left, on the HRD: (source: mnsu) Indeed again, more metals in the stellar mixture modifies post-MS evolution, shifting He-core-burning stars, from the 'Horizontal Branch' (low Z), leftwards, to the 'Red Clump' (high Z) (access-science). The bigger, bloated, higher metallicity stars also (therefore?) rotate less rapidly; and, have higher mass…

So the average density of the sun is supposed to be about 1,400 kilograms per cubic meter, 160,000 kg per cubic meter at the core. I've been thinking about just what a such dense plasma would be like upon close inspection. Aside from the intense heat involved, would it resemble a malleable solid if it were contained in something like a bag? I guess there would be too much matter involved to simply squeeze it around. Does the density involved cause it to change its state into a liquid or solid?

Let me start with a simplequestion. Why we can not see intothe future but it is the only way wecan go, why we can see the past but thereis no way to go back?

I wasn't sure if this belongs in "Classical Physics" or "Astronomy And Cosmology". Anyway, according to Wikipedia, "In most cases, [orbital resonance] results in an unstable interaction, in which the bodies exchange momentum and shift orbits until the resonance no longer exists. Under some circumstances, a resonant system can be stable and self correcting, so that the bodies remain in resonance." I've been wanting to write a science fiction story for a while that takes place on a planet with two moons, and I wanted the moons' orbits to remain roughly stable over many millennia, but am unsure whether to attempt to fit them into a resonance, or whether this would …

I just cant wrap my head around this search for the higgs boson and for that matter the graviton. It makes absolutely no sense. If mass warps spacetime, then that warping is the cause of the effect we call gravity, right? Why do we need force particles in this instance. Obviously Im just a casual reader but maybe you can explain. As for the Higgs, I understand the idea that we dont understand precisely where mass originates, as Brian Cox says, "what make stuff, stuff?" But again I just have a gut feeling that they arent going to find anything, I read somewhere that the higgs was essential to a complete pic of the standard model, why?

Would a BH, accreting matter from an orbiting accretion disk, be orbited, close to or at its EH, by a "ring of light" ?? Please ponder the "head-light effect", whereby accelerated charged particles, moving relativistically, emit hard radiation, focused in their forward direction. Thus, as ions are dragged down into the BH, they will emit "headlights" of radiation, focused forward, around the BH. Would such radiation combine, to produce an annulus of orbiting photons, or "light ring", around the BH ??

Please ponder, a presumed metal-rich asteroid, in our sun's Main Asteroid Belt (MAB), circling our central star, in an assumedly circular orbit ([math]e \approx 0[/math]). And now, please ponder detonating (appropriate, shaped) nuclear charges, on its spin-ward side, to de-orbit the body, and 'drop' it down, onto an earth-crossing trajectory. Now, the largest such earth-crossing orbit, requiring the minimum [math]\Delta v[/math] de-orbit burn, out in the MAB, is the 'earth-touching', tangential, Hohmann transfer orbit: minimal transfer orbit 'drops' body from [math]3 \rightarrow 2[/math] Now, ignoring reduced mass effects, for a rough calculation, w.h.t.: …