Dark matter does not have tiny gravity effects but quite the opposite. Dark matter makes up over a quarter of all the matter in the Universe and Dark Energy is something like 68%. Mass = gravity, you need mass to have gravity, so when you see galaxies and all of their stars and other visible matter you must understand that all that stuff together cannot produce enough gravity to hold it all together. It's dark matter that provides the gravity necessary to hold these galaxies together and without it all of the stars would fly apart. Dark matter is also what provides the gravity necessary to keep entire galaxy clusters together. That "other property" you speak of as other than gravity IS gravity, it's just that we aren't quite sure WHAT is producing that gravity. We call that "what" Dark Matter because we can't see it but we can measure it's gravitational effects as explained before. As far as explaining how the Universe came to be and how that singularity "got there" is a complete mystery to everyone. We know what happened but we don't know what started it or how it came to be. Any answers offered are mere speculation and is often cited by religious folks as the scientific definition of "Let there be light". Which for all we know could very well have been the case. As far as white holes are concerned, General Relativity says they can exist and can be shown to exist using mathematics and Einstein's field equations but I admittedly have almost no knowledge of white holes nor the mathematics involved with them. Any answer I gave in regards to them would be from me simply doing a google search and repeating something I read.
It takes a lot of logistics to launch something in space. It's basically just easier to put something in low Earth Orbit than it is to put it further out than that. Plus for something like the ISS that is manned and requires multiple resupply's it's just easier to keep it as close by as possible. As far as the other space junk yeah a lot of it will simply crash back to Earth and burn up in the atmosphere. Some mission are planned to end with them crashing back to Earth but the engineers involved sometimes direct it to fall in the ocean so as to not harm anything. It doesn't always work out that way though. As we speak there is a Chinese space station on it's way back to Earth and they aren't quite sure where it's going to land which could spell disaster lol. The James Webb Space Telescope is a piece of hardware that requires no repairs or resupply so we are going to launch it and park it well past the Moon at a distance of around 1 million miles away from Earth. That telescope will stay there forever and won't come crashing back down to Earth. It's actually not even going to be orbiting the Earth but at that distance it will be orbiting the Sun. Problem is that it's too far away for us to fix it if we need to so we better hope nothing goes wrong with that thing lol. That's the gamble. Park something close to the Earth for easier access if need be and you have to deal with it crashing back down to Earth at some point. Park out of reach from the Earth and you have to keep your fingers crossed that you built it as good as you think you did or else you're out of luck. Be glad we didn't decide to park Hubble out there lol.
While I agree with your comment it seems like once a capsule or whatever is mostly out of our atmosphere, with less drag and gravity, that going further would be fairly economic? Meteors I thought some were the size of sand or small pebble and could be seen once entering our atmosphere?
Many are extremely small and some are invisible to anyone on Earth...other flare up or explode. Composition plays a major role as does size and speed. Once an object leaves our atmosphere and enters space in indeed loses drag.
So Matter = Mass = Gravity? If there is dark matter then this is mass which has gravity? I thought earlier you implied that galaxy clusters from their mass created enough gravity to hold the clusters and did not require dark matter? It's back to that question is there dark matter between me and the Moon? I guess the answer is yes but it is not needed to keep the Moon orbiting Earth because Earth's gravity has enough mass to create enough gravity? It's hard to imagine all the dynamics of gravity whether it's created by light matter or dark matter and how over vast distances and relatively closer distances can sustain 'everything' with not too much force or too little force but just the right force. And in the case of Earth having it's own gravity, and the Moon having it's own gravity, which I can see the Moon's effect in tidal changes, and with dark matter in between, and gravitational effects from the Sun and other planets, it's interesting that both maintain an equilibrium. It would be great to go back to school and study this stuff but those days are over...
The theory of realistic continued. Feb 13, 2016 Part 1 continued 6.The meaning and value of Geometric Geometry is a branch of maths that is concerned in dealing with the aspects of shape, lines , curves and points , geometrically being a regular existence of lines and shapes thus leading us into a lengthy discussion of the relativeness of Geometry in space. It is important when considering space and in the use of geometry and Minkowski’s space-time, that we do not get obsessed into trying to materialise Minkowski’s space-time into something other than virtual, ignoring any ”truths” of axioms such that lines or curves relatively do not exist in space, relatively curves and lines only exist of objects. Einstein’s relativity, a theory , which is not an axiom, suggests a curvature of Minkowski’s space-time regarding space-time to like’fabric”, however there has never been any physical properties of space observed such as an aether or anything observed of a solidity of space itself. Space is observed as passive, even allowing the propagation of light through space, space offering no resistance to the light. It is of importance though we do not disregard Einstein’s work or Minkowski’s space-time completely, it has huge value in respect to navigation and co-ordination of events in the visual Universe and some of Einstein’s relativity thought is of axiom ”truths” thus far on our understanding and exclusively to our limitations. In the continuation of geometry, I feel it is of importance we bring to the discussion, the geometrical relative size of the visual universe. It is believed by the big bang theory, that before the big bang , nothing existed , not even time. In the above sense, relatively we can describe nothing in geometrical maths terminology 4/3 pi r³ – 4/3 pi r³ = nothing In this maths use expression, it is not important to consider values or put values, the importance of the equation is to consider any size spherical volume and by taking away equal to itself, it leaves nothing. The big bang also suggests that space is expanding, suggesting the size of the visual Universe is ”growing” and that space itself is expanding into nothing. However, this is not an axiom of ”truth”and the evidence that is offered of the Hubble observed red shift, is based on the length between two reflective points . Space itself does not reflect light or is observed to be red shifting, only the incident ray of light impacting an object or the reflective invert of light from objects can red shift relative to the Doppler effect. I propose the basis of evidence suggests that objects are moving away from the observer into more space, rather than the unobserved expansion of space, a length expansion into a unknown distance. Thus brings me to an explanation of a limitation, the limitation being that of light and the diminished magnitude of light over a distance from the source, following that of the inverse square law, relative to observation of objects and the observer. In consideration of the diminished light, let us consider an analogy , which is a comparison between one thing and another of similar context. If in thought we imagine a huge empty warehouse that was in complete darkness, in the center of the warehouse is observer (A) and at a length away from observer (A) standing by the warehouse walls was observer (B). Relative to observer (A) they can not observe (B) Relative to observer (B) they can not observe (A) Relatively both observers can concur by voice the axiom truth, that neither observer can observe each other. Now lets us imagine that observer (A) in the center of the huge warehouse was to place a lit candle by their feet. Relative to observer (A) they can still not observe (B) Relative to observer (B) they can observe (A) Relative to both observers, they can concur by voice that this is the axiom truth of the observation. My reasoning for this relationship is that emitted light is a much a greater magnitude than reflected light. Observer B observes light emitted from the candle flame and a greater magnitude of reflection of the light off (A), where as observer (B) only reflects the extended light that is weakened by the inverse square law by time it arrives at (B). The magnitude of light reflected from (B) is not a great enough magnitude by time the invert reaches (A) and the information of observation is ”washed out” by the candle light surrounding (A). There is no apparent reason why this analogy can not be used on a broader scale of space. We can assume that the axiom holds true on a broader scale, we can assume that the ”black” background of space, is distance, and objects reflect light or emit light over the distance to identify lengths between objects. To extend on this axiom, I would direct the reader to the attention of vanishing points and perspective view. A body in motion travelling away from an observer relative to observation will appear to decrease in size to an eventual point of appearing to not exist, down scaling into nothing. This can be described in analogy by using a train track. If in imagination we are standing on the train track observing a train travelling away from us , relatively we observe the train’s observed rear area, scaling down in size. This area contraction can be acquainted to the Lorentz formula and length contraction, length contraction being that of perspective parallel nature, where as the perspective linear view relative nature to motion of the object differs in that the whole area of the viewed object contracts to a point of nothingness relative to a linear velocity between two bodies. Thus brings us to the relative geometrical size of the visual Universe, there is a ”truth” in that the size is relative to the reflectiveness or the emittance of the furthest away object, there is also a ”truth” that this does not show us any relative size to the Universe and space itself, this only shows us relative length between objects relative to light. To describe the visual universe in geometrical maths, we can write the expression 4/3 pi r(c)³ Where r(c) represents the radius of light we observe from a localised point of the Universe corresponding to a distant body and relative to the length of light between bodies.
To go greater distances is mostly a matter of time but I guess time = money. I assume the Chinese space station is crashing back to Earth because it doesn't have orbit adjusting thrusters or it does but they want it to return. Reading about the James Webb Telescope...wow...what an endeavor! A solar orbit. If something can be placed in orbit why can't it also be removed from orbit...or at least bring it closer to Earth in case of repairs?
I think saying the universe is exanding is not really how physicists say it's happening, and I'm not one so I could be wrong. Space itself is expanding. The Big Bang is sort of misinterpreted as everything that ever is or going to be flying away from some point of origins. The space between objects is increasing. What's your real question, what happened or existed before the Big Bang? The answer is those are events before t=0. It's almost like asking what the score of a football game was 10 minutes before kick off. There was no football game as of yet, how could there be a score? Stephen Hawking actually proposed this as evidence that the universe is infinate. General relativity and quantum mechanics don't play well together, so it's impossible to understand. Was there something around the singularity before expansion started? Nobody knows, but whatever the case may be it would just be more universe and more space.
Yes dark matter has mass. When I stated earlier that these galaxy clusters have enough mass to hold themselves together I was including dark matter into that statement. A galaxy's mass includes the matter than you can see (stars, planets, asteroids, etc) AND dark matter. In fact without dark matter there would be no galaxies at all let alone galaxy clusters. There is dark matter between you and the Moon it's just negligible here in the solar system to the point where it's barely even measurable if measurable at all. Dark matter starts to become a requirement on a galactic scale. Basically if all dark matter in the Universe vanished then there would still be solar systems. Stars have enough gravity to keep things in orbit on their own, however, the collective gravity of all stars within a galaxy is not enough to keep all of the stars together within that galaxy. That is where dark matter comes in to play. One of the reasons why gravity around here seems to be in perfect harmony is because you are alive and talking about it lol. What I mean is that it's not always like that in the Universe, there are some harsh places out there where gravity is nowhere near in equilibrium and it's chaos. Planets getting non stop bombarded by asteroids and/or other planets. Planets getting slung completely out of their own solar systems, planets getting ripped apart by gravity, black holes eating stars, etc. Our backyard is relatively stable which is of course why we are even here having this discussion. But depending on what time throughout history you visit or place in the galaxy or universe you visit you may very well see anything but perfect harmony with gravity.
I'm no engineer but from what I understand about James Webb is that it's a super delicate instrument that is not designed to be repaired. None of the parts on it are replaceable and it wasn't designed with any sort of architecture that would allow astronauts to even grab a hold of it anywhere to fix anything. Plus due to where they are placing it and the cost of the telescope it would be almost cheaper to just build a whole other one and try again if it happened to need fixing. That thing is going pretty far away, in order for it to get back near the Earth for repairs would require it to have a pretty expensive propulsion and guidance system which would likely throw the mechanics of the whole thing off and of course add a considerable amount of weight to it which would cost more money. Basically due to how delicate James Webb is and where it's going to be positioned it would cost less money to just build a new one than to spend the money to launch a mission to repair it if something goes wrong. I'll tell you what few things will have me more nervous than watching James Webb launch and get into position. I've been following the development of that telescope for the better part of 15 years. If it doesn't work properly I'd probably end up calling in sick for work that day lol. Fingers crossed!
Maybe Drake's Equation should have another variable...gravity? Gravity effects must have some level of harmony which we are lucky to have. Thinking about the Sun or Milky Way moving through space at ~500,000 mph...is almost unfathomable to me so between the gravity of light and dark matter there must be some perfect equilibrium. Amazing that solar systems and galaxies can be held together yet something like Voyager I-II can move through space with little effect from gravity. If we were to send a craft towards the nearest star, if that star and our Sun are moving apart at ~500,000 mph, then how could that craft ever reach the other star unless it travels at 500,000 mph + 1? Maybe dark matter is the key to space travel?
Now we have throw-away telescopes? Yes a lot will be riding on the launch and positioning and how many variables are there for something to go wrong? It's pretty amazing the technology and precision and luck that goes into these instruments. I guess the one advantage is there is no human life to worry about...just the cost and time for such ventures...
The Sun and the other stars in the Milky Way aren't moving apart at 500,000 mph. While the Sun is moving at that speed so are the other stars in the Milky Way (more or less) but we also know their orbits. It's the same reason why we can launch probes to intercept other planets. We know how fast they are travelling and the orbits they are travelling so we simply pick a spot in their orbit to intercept them, usually when they are closest to Earth. We'd do the same thing with other stars when we launch probes there, just on a larger scale. Basically if we know it's going to take our probe 100 years to reach the star then we will launch it on a trajectory to where it will intercept where the star will be in 100 years. Remember, stuff in the galaxy is just like the stuff in our solar system only on a much larger scale. The planets orbit the Sun in elliptical orbits, and the stars in the galaxy, including the Sun and it's planets (us) orbit the Milky Way roughly the same way. Remember galaxies "stick together" because of Dark Matter. The other stars aren't flying away from us, they are orbiting the center of the galaxy just like we are. Voyager is moving through space BECAUSE of gravity. Voyager had to "sling shot" around Jupiter and Saturn in order to escape the Solar System. Remember when we discussed stuff falling back to the Earth? Well think of that on a larger scale. Stuff near the Earth falls back to the Earth if it's going too slow. Well stuff in the Solar System falls back to the Sun if it's going too slow. Voyager didn't have the velocity needed to "go fast enough" to NOT get brought back by the Sun's gravity. So in order to gain speed it used Jupiter's and Saturn's gravity to "sling shot" itself around the planet and gain the velocity needed to escape the Sun's gravity. So your thinking is correct, those probes wouldn't be able to move through space with little effect from gravity if they weren't going fast enough, the Sun controls our Solar System and it's gravity is immense. If you aren't going fast enough to escape the influence of the Suns gravity then it will grab you and pull you back. Just like the Earth will grab you and pull you back if you aren't in perfect harmony and "falling with the Earth" as it moves through it's orbit. Every object with mass (remember mass=gravity) has what's called an escape velocity. Depending on how strong the gravity is will determine what escape velocity you need to achieve in order to, well, "escape" it. There are objects out there that have no escape velocity, their gravity is so strong that no matter how fast you are going you can never go fast enough to escape them, even going the speed of light isn't enough to escape their gravity. There objects are appropriately named "black holes" because not even light travelling at the speed of light can escape them.
It's not really a throw away telescope but one that is so delicate yet "well built" that it isn't supposed to have any issues. Plus where we are parking that thing it's just too far away for us to go mess with it if something does go wrong. They have tested and tested and retested that thing for almost every possible scenario and it's passed all tests. But at the end of the day it's still a machine built by man, the thing CAN break....I trust the engineers who built it but I'm with you....I REALLY HOPE they built it as well as they think they did lol...I know it sounds ridiculous but space nerd stuff has been my favorite hobby since I was 3 years old. Watching James Webb launch will be one of the most nerve racking experiences in my life. Somebody on Reddit a few weeks ago made a joke saying "You know what would suck would be if after all this time and effort and money we go to launch this thing and the rocket blows up on the pad". I've rarely ever wanted to actually come through the computer screen and yell at somebody before. Don't say that! LOL
I thought everything in the Universe was expanding, not from a single point, but expanding in all directions? And that this rate of expansion was approximately 500K mph? As if all the dark matter in between light matter was growing in size and pushing light matter in all directions at basically the same velocity? As this expansion continues, if we think distances are enormous today, every day that passes these distances increase? So within our galaxy it's the gravity of light matter, plus the gravity of dark matter, that holds the galaxy cluster together, making the inhabitants of a galaxy cluster kind of immune from the expansion of the Universe? The gravity of light matter within a cluster is strong enough to sort of neutralize the expansion properties of dark matter? But in between the galaxy clusters it is dark matter that rules? Notice above every sentence is a question...shows how stupid I am. I understand the escape velocity issue regarding Voyager and other craft. Seems like all mass in the Universe must maintain some velocity in order to resist gravity; Earth must maintain a velocity to avoid being sucked into the Sun, and the Sun must maintain a velocity to avoid being sucked into other stars in the galaxy. If it's dark matter that creates this expansion or velocity, then this is great because without dark matter the Universe will contract into one glob. Some level of velocity of all mass must be maintained in order to prevent gravity from pulling everything together? And if and when this does not happen does this create black holes? Like you said in a black hole even the SOL is not enough velocity for light to escape. Does this ultimately mean Velocity Rules?
Well not throw-away but there is no warranty return policy. It all boils down to one chance to launch it, one chance to get it into orbit, and one chance for it to work to expectations. 100x more powerful than Hubble should give some 'out of this world' results...
Think of galaxies like giant cities. The cities themselves are expanding away from one another (unless bound by gravity in clusters) but the stuff within the cities themselves is not expanding away from one another because the gravity within the cities is strong enough to hold them together. You are getting Dark Matter and Dark Energy confused. Matter and Dark Matter combined is what holds galaxies together and sometimes holds galaxies together in clusters. Dark Energy is what is driving the accelerated expansion of the galaxies away from each other on a Universal scale. Dark Matter isn't growing in size and pushing stuff away from each other. Yup, every day that passes these distances between galaxies increases. It increases at a faster rate the further away the galaxy is from us. So the ones close to us are expanding away as well but the ones at the very edge of our Observable Universe are expanding even faster. Eventually, in billions and billions of years in the future, all galaxies will have expanded beyond our light horizon, the edge of our Observable Universe, and we will never see them again. We could still look up and see stars because we are in the Milky Way, and we'd still see our neighbors in the Local Group who are bound together with us in our galaxy cluster. But beyond that, there will be nothing. But you don't have to worry about that, by the time that happens we will of course be long gone. Dark matter creates the gravity, Dark Energy drives the expansion. Velocity does rule but it doesn't make you immune to gravity. Even while moving pretty quick if you get close enough to something with pretty massive gravity then it will likely slingshot you to some random trajectory. It's actually a good thing, Jupiter for example is our big brother in the Solar System that shields us from deadly asteroids and comets. Comets often come towards the inner solar system from out in the Oort Cloud (way past Neptune) and it's Jupiter that tends to slingshot them our of the Solar System before they reach the inner planets where we live. Without those outer gas giants out there with their immense gravity to redirect these comets we inner planets would be getting hit with dinosaur killer style asteroids a bit more often. Black holes are formed when a big enough star (about 20 times as massive as our Sun) collapses in on itself. A star, for all intents and purposes, is a huge continuous series of nuclear bombs going off with the gravity of the star holding them all together in a giant sphere. And as we discussed before with equilibrium it's the same thing here. Gravity and the nuclear reactions are in harmony so the star stays alive and stable. Problems arise when the star runs out of nuclear fuel to use and then the immense gravity of the star causes it to collapse in on itself. Stars that big "blow up" in what we call Supernovae once they run out of fuel. They blow their outer layers away leaving nothing but the core of the star. The core then collapses in on itself due to it's own weight and once it does that you are left with a black hole. Not a stupid question at all! Astrophysics can be very confusing. It's hard to wrap your head around a lot of this stuff because it's so "weird". This has been my favorite hobby since I was a preschooler and decades later I still often times read an article or a journal on something involving Astrophysics and I stop and think "what the hell are they talking about?" Yes to the first question. But it's the gravity of light matter AND dark matter that holds galaxy clusters together as well. Dark matter rules both in and out of galaxies. Without it the combined gravity of all "light matter" would not be enough to hold galaxies OR galaxy clusters together. Without dark matter then there would be no galaxies but rather a bunch of random stars scattered everywhere in the Universe.
Don't get "too excited" about what you will see with James Webb. James Webb is an IR telescope. Yes it is much more powerful than Hubble but not really in the way you think. You aren't going to see "Hubble Style" pictures of Exoplanets or anything. It will be an amazing piece of hardware and an excellent tool for science, but understand that this is a science telescope. It's not there to give pretty pictures of outer space. It will be a leap forward from Hubble, but it will be nowhere near as big a leap as when Hubble first launched. Going from ground based telescopes to Hubble was incredible, but you won't get that same leap here. Basically the pictures we get back from James Webb and put on the internet for the public to see will look pretty much the same as the pictures Hubble already shows you. It can see farther but I mean to most people a galaxy is a galaxy regardless of how far away it is. One of the best things James Webb will supposedly do is snap us some pictures of Exoplanets. But don't expect this: Expect more like this....and even that might be pushing it.
