Space science & general science ...

What is Dark Matter? By BALBEER SINGH DANU This Hubble Space Telescope composite image shows a ghostly "ring" of dark matter in the galaxy cluster Cl 0024+17. Credit: NASA, ESA, M.J. Jee and H. Ford (Johns Hopkins University) Roughly 80 percent of the mass of the universe is made up of material that scientists cannot directly observe. Known as dark matter, this bizarre ingredient does not emit light or energy. So why do scientists think it dominates? Studies of other galaxies in the 1950s first indicated that the universe contained more matter than seen by the naked eye. Support for dark matter has grown, and although no solid direct evidence of dark matter has been detected, there have been strong possibilities in recent years. The familiar material of the universe, known as baryonic matter, is composed of protons, neutrons and electrons. Dark matter may be made...

  What is Dark Energy? by; balbeer singh danu MORE The galaxy cluster Abell 1689 is famous for the way it bends light in a phenomenon called gravitational lensing. Study of the cluster has revealed secrets about how dark energy shapes the universe. Credit: NASA, ESA, E. Jullo (JPL/LAM), P. Natarajan (Yale) and J-P. Kneib (LAM) A mysterious quantity known as dark energy makes up nearly three-fourths of the universe, yet scientists are unsure not only what it is but how it operates. How, then, can they know this strange source exists? The expanding universe In 1929, American astronomer Edwin Hubble studied exploding stars known as supernovae to determine that the universe is expanding. Since then, scientists have sought to determine just how fast. It seemed obvious that gravity, the force which draws everything together, wou...

What is gravity? Gravity is a force pulling together all matter (which is anything you can physically touch). The more matter, the more gravity, so things that have a lot of matter such as planets and moons and stars pull more strongly. Mass is how we measure the amount of matter in something. The more massive something is, the more of a gravitational pull it exerts. As we walk on the surface of the Earth, it pulls on us, and we pull back. But since the Earth is so much more massive than we are, the pull from us is not strong enough to move the Earth, while the pull from the Earth can make us fall flat on our faces. In addition to depending on the amount of mass, gravity also depends on how far you are from something. This is why we are stuck to the surface of the Earth instead of being pulled off into the Sun, which has many more times the gravity of the Earth.  Is there gravity in space? There is gravity everywhere. It gives shape to the ...

HOW WILL YOU PROVE THAT PROTON HAS MOMENTUM USING E2 = m2c4 + p2c2 ? I dont know how much you know abt Relativity Physics. The answer in short is below ( without detail derivation ,since it is difficult to write math eqn here.)  momentum vector p = M u = m u / sqrt ( 1- u^2/c^2)  here M is mass of relativistic particle and m is mass at rest generally written as m zero  p^2 = p.p = m^2 u^2 c^2/C^2-u^2  p^2c^2 = u^2(p^2+m^2+c^2) ---------- (i)  Now E = M c^2 = mc^2 / sqrt ( 1- u^2/c^2)  E^2 = m^2 c^6 / c^2- u^2 ------------ (ii)  using eqn i and ii  E^2 = p^2c^2+ m^2c^4  Photon at rest m =0  E = pc. What would the universe be like if the speed of light was infinite? First of all, the speed of light being infinite really has two different meanings in physics, either it means:  1. The maximum speed at which anything can travel is infinite. OR  2. The speed at which photons themselves travel is infinite. ...

                                                       #тнє_єχραnding_Universe For thousands of years, astronomers wrestled with basic questions about the size and age of the universe. Does the universe go on forever, or does it have an edge somewhere? Has it always existed, or did it come to being some time in the past? In 1929, Edwin Hubble, an astronomer at Caltech, made a critical discovery that soon led to scientific answers for these questions: he discovered that the universe is expanding. The ancient Greeks recognized that it was difficult to imagine what an infinite universe might look like. But they also wondered that if the universe were finite, and you stuck out your hand at the edge, where would your hand...

  Q: What is electromagnetic energy? A: Electromagnetic energy is a form of energy that can be reflected or emitted from objects through electrical or magnetic waves traveling through space. Electromagnetic energy comes in many examples including gamma rays, X-rays, ultraviolet radiation, visible light, microwaves, radio waves and infrared radiation. Explain: The electromagnetic spectrum is the range of all types of electromagnetic radiation (electromagnetic radiation being a type of electromagnetic energy). Electromagnetic radiation is a kind of energy that travels and spreads outward as it goes, such as the lamp sending visible light in a person's home or the radio waves coming from the radio station. People encounter electromagnetic spectrum energy all the time. Radio electromagnetic energy can be seen not only in the radio waves captured and emitted by radio stations, but also in the radio waves emitted by gases in space and stars in space. The micr...