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beecee

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Everything posted by beecee

  1. Hmmm is that so? How about a laser beam? Just to add, it maybe correct that we see the Sun as it was 8.25 minutes ago, but what we see is as much reality as it is for anyone that was on the surface of the Sun. eg: If the Sun was big enough to go S/Nova, we would still be experiencing it for 8.25 minutes....just as real as our intrepid friend on the surface of the Sun, that was blown out of existence 8.25 minutes before.
  2. To keep humans going, is certainly the main impetus for reaching for the stars. But the nature of man, the adventure aspect in some of us, the never ending search for knowledge, and simply the fact "that its there" will always drive us forward I believe, and will continue at least until we either destroy ourselves, or that scenario is assisted by some catastrophic disaster.
  3. The exact mechanism by which the Moon is moving away from the earth, goes like this..... The Moon attracts the Oceans which because of the earth's revolving on its axis, sees the Oceans moving slightly ahead of the overhead Moon. This has the effect of "pulling" the Moon into a higher orbit, and at the same time, the tidal frictions of the Oceans, is slowing the earth by a tiny amount. In time, around a billion years or so, the Moon will be much further away, and the Earth will have one side permanently facing the Moon, just as the Moon now has one side permanently facing Earth. A day on Earth will then be equal to around a month. Of course around that same time, the Sun will have started to reach its giant red phase and whether we will be around anyway is doubtful.
  4. Yes, that error stood out like the proverbial....
  5. Yes, good questions certainly, and the methodology explained in https://www.youtube.com/watch?v=MO0r930Sn_8 or are you perhaps suggesting some omnipotent Spaghetti Monster or magical sky pixie? Here is another well constructed answer if you would really like to know. https://van.physics.illinois.edu/qa/listing.php?id=31235&t=why-does-a-magnet-have-north-and-south-poles Not really...... https://en.wikipedia.org/wiki/Magnet Ancient people learned about magnetism from lodestones, which are naturally magnetized pieces of iron ore. The word magnet was adopted in Middle English from Latin magnetum "lodestone", ultimately from Greek μαγνῆτις [λίθος] (magnētis [lithos])[1] meaning "[stone] from Magnesia",[2] a part of ancient Greece where lodestones were found. Lodestones, suspended so they could turn, were the first magnetic compasses. The earliest known surviving descriptions of magnets and their properties are from Greece, India, and China around 2500 years ago.[3][4][5] The properties of lodestones and their affinity for iron were written of by Pliny the Elder in his encyclopedia Naturalis Historia.[6] By the 12th to 13th centuries AD, magnetic compasses were used in navigation in China, Europe, the Arabian Peninsula and elsewhere I don't believe "quote from the internet" is good enough. I mean while the Internet is a great tool for learning, the freedom given to everyone, means that we will also have plenty of nonsensical claims and mythical explanations given by those with a particular barrow to push.eg: religious sites and the like. So can the forum please have an exact link as to where you do get your information from. Thanks.
  6. Before making up nonsense, perhaps you need to read some reputable appropriate material as to what causes magnetic fields. Then if you truly want to complement what you have learnt, listen to the excellent "Feynman" link that Strange gave: It's only 7.5 minutes long.
  7. Hmm, that sounds like a confession. It appears I may have been right afterall.
  8. Your confusion exists in not wanting to accept the fact that there is no universal now. eg: You look at Alpha Centauri tonight, and you are seeing it as it was 4.5 years ago. Theoretically in may have gone supernova in the meantime. But irrespective, your frame of reference is valid, as is the frame of any intelligence orbiting Alpha Centauri. Rubbish, and total word salad. As I previously said the other day, it appears you do not want to accept an answer due to some agenda. Sound waves have nothing to do with stellar distance measuring, in fact in space no one can here you scream! It appears from where I'm sitting, that its your own train of thought that's in dispute, and you are unable to accept, let alone comprehend any answer that conflicts with whatever personal baggage you hold.
  9. https://en.wikipedia.org/wiki/Stellar_parallax http://hubblesite.org/hubble_discoveries/dark_energy/de-type_ia_supernovae.php http://sci.esa.int/education/35616-stellar-distances/?fbodylongid=1673 As a lay person, my replies are generally dumbed down...Not sure how much further dumbing down I can do.
  10. To a star, simple "stellar parallex"....to another galaxy, standard candles such as Type1a Supernova, Ceipheid Variables, in conjunction with cosmological redshift.
  11. NASA team studies middle-aged Sun by tracking motion of Mercury January 18, 2018 by Elizabeth Zubritsky, NASA's Goddard Space Flight Center Like the waistband of a couch potato in midlife, the orbits of planets in our solar system are expanding. It happens because the Sun's gravitational grip gradually weakens as our star ages and loses mass. Now, a team of NASA and MIT scientists has indirectly measured this mass loss and other solar parameters by looking at changes in Mercury's orbit. The new values improve upon earlier predictions by reducing the amount of uncertainty. That's especially important for the rate of solar mass loss, because it's related to the stability of G, the gravitational constant. Although G is considered a fixed number, whether it's really constant is still a fundamental question in physics. "Mercury is the perfect test object for these experiments because it is so sensitive to the gravitational effect and activity of the Sun," said Antonio Genova, the lead author of the study published in Nature Communications and a Massachusetts Institute of Technology researcher working at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Read more at: https://phys.org/news/2018-01-nasa-team-middle-aged-sun-tracking.html ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: the paper:: https://www.nature.com/articles/s41467-017-02558-1 Solar system expansion and strong equivalence principle as seen by the NASA MESSENGER mission: Abstract: The NASA MESSENGER mission explored the innermost planet of the solar system and obtained a rich data set of range measurements for the determination of Mercury’s ephemeris. Here we use these precise data collected over 7 years to estimate parameters related to general relativity and the evolution of the Sun. These results confirm the validity of the strong equivalence principle with a significantly refined uncertainty of the Nordtvedt parameter η = (−6.6 ± 7.2) × 10−5. By assuming a metric theory of gravitation, we retrieved the post-Newtonian parameter β = 1 + (−1.6 ± 1.8) × 10−5 and the Sun’s gravitational oblateness, J2⊙J2⊙ = (2.246 ± 0.022) × 10−7. Finally, we obtain an estimate of the time variation of the Sun gravitational parameter, GM⊙°∕GM⊙GM⊙°∕GM⊙ = (−6.13 ± 1.47) × 10−14, which is consistent with the expected solar mass loss due to the solar wind and interior processes. This measurement allows us to constrain ∣∣G°∣∣∕GG°∕G to be <4 × 10−14 per year.
  12. https://phys.org/news/2018-01-neutron-star-merger-yields-puzzle-astrophysicists.html Neutron-star merger yields new puzzle for astrophysicists January 18, 2018, McGill University: The afterglow from the distant neutron-star merger detected last August has continued to brighten - much to the surprise of astrophysicists studying the aftermath of the massive collision that took place about 138 million light years away and sent gravitational waves rippling through the universe. New observations from NASA's orbiting Chandra X-ray Observatory, reported in Astrophysical Journal Letters, indicate that the gamma ray burst unleashed by the collision is more complex than scientists initially imagined. "Usually when we see a short gamma-ray burst, the jet emission generated gets bright for a short time as it smashes into the surrounding medium - then fades as the system stops injecting energy into the outflow," says McGill University astrophysicist Daryl Haggard, whose research group led the new study. "This one is different; it's definitely not a simple, plain-Jane narrow jet." Read more at: https://phys.org/news/2018-01-neutron-star-merger-yields-puzzle-astrophysicists.html#jCp ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: the paper: http://iopscience.iop.org/article/10.3847/2041-8213/aaa4f3/meta Brightening X-Ray Emission from GW170817/GRB 170817A: Further Evidence for an Outflow: Abstract The origin of the X-ray emission from neutron star coalescence GW170817/GRB 170817A is a key diagnostic of the unsettled post-merger narrative, and different scenarios predict distinct evolution in its X-ray light curve. Due to its sky proximity to the Sun, sensitive X-ray monitoring of GW170817/GRB 170817A has not been possible since a previous detection at 16 days post-burst. We present new, deep Chandra observations of GW170817/GRB 170817A at 109 days post-burst, immediately after Sun constraints were lifted. The X-ray emission has brightened from a 0.3–8.0 keV flux of erg s−1cm−2 at 16 days to erg s−1 cm−2 at 109 days, at a rate similar to the radio observations. This confirms that the X-ray and radio emission have a common origin. We show that the X-ray light curve is consistent with models of outflow afterglows, in which the outflow can be a cocoon shocked by the jet, dynamical ejecta from the merger, or an off-axis structured jet. Further deep X-ray monitoring can place powerful constraints on the physical parameters of these models, by both timing the passing of a synchrotron cooling break through the X-ray band and detecting the associated steepening of the X-ray photon index. Finally, the X-ray brightening strengthens the argument that simple off-axis top-hat jet models are not consistent with the latest observations of GW170817/GRB 170817A.
  13. Even inter planetary space, or interstellar space is not quite a pure vacuum by definition, but getting pretty damn close I would say. definition: Space in which there is no matter or in which the pressure is so low that any particles in the space do not affect any processes being carried on there. It is acondition well below normal atmospheric pressure and is measured in units of pressure (the pascal). https://www.quora.com/What-is-a-vacuum-condition
  14. In simple language, a set of dimensions of an object, [length breadth and width] needed to specify or locate that object: Time then is needed to specify when in space that object is. Sound, smell etc I would class as properties of that particular object.
  15. Electricity by definition is the flow of electrons. Space, or a total vacuum, does not conduct electricity. But sometimes if the electromotive force, [Voltage] is strong enough then it can "shoot"electrons across a limited distance that maybe a vacuum. PS: Just a request from an old retired lay person, why don't you get rid of the chip on your shoulder? ...or discard whatever agenda you have...Or whatever it is that makes you so aggressive and using such abusive language.
  16. https://phys.org/news/2018-01-massive-neutron-stars.html#ms How massive can neutron stars be? Astrophysicists at Goethe University Frankfurt set a new limit for the maximum mass of neutron stars: They cannot exceed 2.16 solar masses. Since their discovery in the 1960s, scientists have sought to answer an important question: How massive can neutron stars actually become? By contrast to black holes, these stars cannot gain in mass arbitrarily; past a certain limit there is no physical force in nature that can counter their enormous gravitational force. For the first time, astrophysicists at Goethe University Frankfurt have succeeded in calculating a strict upper limit for the maximum mass of neutron stars. With a radius of about 12 kilometres and a mass that can be twice as large as that of the sun, neutron stars are amongst the densest objects in the universe, producing gravitational fields comparable to those of black holes. Whilst most neutron stars have a mass of around 1.4 times that of the sun, massive examples are also known, such as the pulsar PSR J0348+0432 with 2.01 solar masses. Read more at: https://phys.org/news/2018-01-massive-neutron-stars.html#jCp :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: the paper: http://iopscience.iop.org/article/10.3847/2041-8213/aaa401/meta Using Gravitational-wave Observations and Quasi-universal Relations to Constrain the Maximum Mass of Neutron Stars Abstract Combining the GW observations of merging systems of binary neutron stars and quasi-universal relations, we set constraints on the maximum mass that can be attained by nonrotating stellar models of neutron stars. More specifically, exploiting the recent observation of the GW event GW170817 and drawing from basic arguments on kilonova modeling of GRB 170817A together with the quasi-universal relation between the maximum mass of nonrotating stellar models and the maximum mass supported through uniform rotation , we set limits for the maximum mass to be , where the lower limit in this range comes from pulsar observations. Our estimate, which follows a very simple line of arguments and does not rely on the modeling of the electromagnetic signal in terms of numerical simulations, can be further refined as new detections become available. We briefly discuss the impact that our conclusions have on the equation of state of nuclear matter.
  17. Just snoozing While we certainly do not know the exact pathway and methodology, the fact is that at one time there was no life anywhere, then the next minute there was. Speaking scientifically, we can really only conclude Abiogenesis.
  18. How are you able to say science can and will never know how life originated? In actual fact and universally speaking, Abiogenesis appears to be really the only scientific answer as to how life arose.
  19. Are you referring to the way heat is "transported"? If so, we have three methods...conduction, convection and radiation. Heat is transmitted through space by the latter....radiation
  20. Sadly, an otherwise great scientist, who achieved great things such as the the theory of nuclear synthesis process undertaken in stars.
  21. Take it easy fella! You must accept that if you post nonsense, you will be called out to support your nonsense. Spitting the dummy, is not really the answer.
  22. Well firstly you do not have a theory. You have a silly personal hypothetical belief, most probably driven by some agenda. The current theory of gravity has been tested and continues to be tested and validated everyday, despite nonsense we often see on forums such as this, open to any Tom, Dick or Harry.
  23. Before I attempt to answer that question, the first step that you need to accept is that time dilation is experimentally and observationally verified and has been many times. If you are unable to accept that, because it presumably offends your personal sensibilities and seems personally counter intuitive, then you have a problem. Let me add another fact...Your offended intuition, of course only applies to a very limited set of conditions. Those conditions though, with the advances in science and technology, have been extended many times, and it is consequently evident that things that were once intuitively accepted, are not valid when relativistic speeds, gravitational wells and temperatures are experienced or brought into vogue. As simply as I am able to put it, and from one lay person to another, time dilation occurs because the proper speed of light, "c" is the same for all observers in all frames of references. Thus time dilation is evident when two different observers are moving with relation to each other, or when residing in a different gravitational well. At Earthly based speeds and pre-Einstein, this effect was not noticed due to it being very very tiny, and only becomes noticable when moving at near relativistic speeds. On any other questions of "why" or "how" that you have, you should realize that science is based on a preponderance of evidence supporting a particular concept. The following short video of around 7.5 minutes long may explain exactly what I'm trying to say...... https://www.youtube.com/watch?v=MO0r930Sn_8
  24. Good question! And although empirical evidence to the answer to that question is absent at this time, universally speaking, the only scientific answer to how life first arose is Abiogenesis, despite scientists at this time not knowing by what exact methodology and detail. The fact that we are here, supports the only scientific answer of Abiogenesis. Plus of course it is not a scientific answer to the question of how life arose.
  25. I doubt it is as you actually say...there are always two sides to each story. In my own words and lay person's description, let me say that time is real...it stops everything from happening together...just as space is real and stops everything from being in the same spot. Which leads us to the concept of spacetime which is also real. Or to put that in more scientific elaborate terms, spacetime can be described as a "unified" framework within which we locate events and describe the relationships between them in terms of spatial coordinates and time. The concept of spacetime follows from the observation that the speed of light is invariant, i.e. it does not vary with the motion of the emitter or the observer. Spacetime allows a description of reality that is common for all observers in the universe regardless of their motion. Your space is your space...your time is your time and may differ to mine. https://www.youtube.com/watch?v=FVINOl0Ctfk
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