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Three Good Reasons to Not Send Humans to Mars — SpaceBounder. Those were different times. NASA's Apollo mission was a flag-planting mission, after which astronauts packed up, hopped back onto their expensive spacecraft, and arrived back on Earth in time for their scheduled parade. So planting a flag on the Moon is one of the big things that came out of the Cold War. The other big thing almost ended up being the destruction of the human race in a global nuclear war, but that's all water under the Moon. And it's not the Cold War anymore, so there's no need for all that flag-toting. It's no longer competition that will get humans to Mars, but cooperation. It's no longer nationalism that will drive one country to succeed on the red planet, but international effort that will drive a united team of nations. We won't be going to Mars to plant flags, we'll be going to explore and learn.
Humanity's eventual journey through interplanetary space and landing on Mars won't be about winning; it will be about progress. Scientists work out how create matter from light, to finally prove Einstein's E=mc2 - ExtremeTech. This site may earn affiliate commissions from the links on this page. Terms of use. Physicists in England claim they have discovered how to create matter from light, by smashing together individual massless photons– a feat that was first theorized back in 1934, and has been considered practically impossible until now.
If this new discovery pans out, the final piece of the physics jigsaw puzzle that describes how light and matter interact would be complete. No one’s quite sure of the repercussions if matter can indeed be produced from photon-photon collision, but I’m sure something awesomely scientific will emerge before long. Way back in 1930, British theoretical physicist Paul Dirac theorized that an electron and its antimatter counterpart (a positron) could be annihilated (combined) to produce two photons. Various photon-mass reactions, theorized and proven over the years The reason it’s proven hard to observe is that photons, a lot like neutrinos or electrons, are incredibly small. Scientists discover how to turn light into matter after 80-year quest. Imperial College London physicists have discovered how to create matter from light - a feat thought impossible when the idea was first theorised 80 years ago.
In just one day over several cups of coffee in a tiny office in Imperial's Blackett Physics Laboratory, three physicists worked out a relatively simple way to physically prove a theory first devised by scientists Breit and Wheeler in 1934. Breit and Wheeler suggested that it should be possible to turn light into matter by smashing together only two particles of light (photons), to create an electron and a positron – the simplest method of turning light into matter ever predicted.
The calculation was found to be theoretically sound but Breit and Wheeler said that they never expected anybody to physically demonstrate their prediction. It has never been observed in the laboratory and past experiments to test it have required the addition of massive high-energy particles. More information: Pike, O, J. et al. 2014. Scientists Work Out How To Make Matter From Light. Matter creation - Wikipedia. Scientists Use Light to Create Particles. Scientists Using Light to Create Particles Scientist Can now Create Matter Out of NothingBy Malcom W. Browne Scientist Can now Create Matter Out of Nothing Scientists Use Light to Create Particles A trailblazing experiment at the Stanford Linear Accelerator Center in California has confirmed a longstanding prediction by theorists that light beams colliding with each other can goad the empty vacuum into creating something out of nothing. In a report published this month by the journal Physical Review Letters, 20 physicists from four research institutions disclosed that they had created two tiny specks of matter -- an electron and its antimatter counterpart, a positron -- by colliding two ultrapowerful beams of radiation.
The possibility of doing something like this was suggested in 1934 by two American physicists, Dr. Gregory Breit and Dr. Dr. This breakdown of the vacuum by an ultrastrong electromagnetic field was hypothesized in 1950 by Dr. Copyright 1997 The New York Times.
Moon encylopiedia. Essential question research. Deep Space Industries. Deep Space Industries, or DSI,[6] is an American privately-held company with global operations, operating in the space technology and resources sectors. The company is developing spacecraft technologies that are needed for asteroid mining, and is currently selling satellites that use these technologies. DSI is expecting to make in-space materials, extracted from asteroids, commercially available in the early 2020s, include space-based refueling, power, asteroid processing, and manufacturing.[6] History[edit] DSI was formally announced on January 22, 2013[5] and currently has three spacecraft and patent-pending microgravity manufacturing technologies under development. According to David Gump, founding CEO, speaking at the company's launch in Santa Monica, California, another early goal of the company is to refuel communications satellites that contain a refueling interface.
Spacecraft and technologies[edit] Criticism[edit] The announcement of DSI was met with both praise and criticism. Variable Specific Impulse Magnetoplasma Rocket. Electrothermal thruster in development Artist's impression of a multi-megawatt VASIMR spacecraft Design and operation[edit] VASIMR is a type of electrothermal plasma thruster/electrothermal magnetoplasma thruster. In these engines, a neutral, inert propellant is ionized and heated using radio waves. The resulting plasma is then accelerated with magnetic fields to generate thrust. The propellant, a neutral gas such as argon or xenon, is injected into a hollow cylinder surfaced with electromagnets. A second coupler, known as the Ion Cyclotron Heating (ICH) section, emits electromagnetic waves in resonance with the orbits of ions and electrons as they travel through the engine.
The path of ions and electrons through the engine approximates lines parallel to the engine walls; however, the particles actually orbit those lines while traveling linearly through the engine. Advantages[edit] Disadvantages[edit] Research and development[edit] VX-10 to VX-50[edit] VX-100[edit] VX-200[edit] VX-200SS[edit] Electrically powered spacecraft propulsion. For vehicles other than spacecraft that are propelled by electric means, see Electric vehicle.
An electrically powered spacecraft propulsion system uses electrical energy to change the velocity of a spacecraft. Most of these kinds of spacecraft propulsion systems work by electrically expelling propellant (reaction mass) at high speed, but electrodynamic tethers work by interacting with a planet's magnetic field.[1] Electric thrusters typically use much less propellant than chemical rockets because they have a higher exhaust speed (operate at a higher specific impulse) than chemical rockets.[2] Due to limited electric power the thrust is much weaker compared to chemical rockets, but electric propulsion can provide a small thrust for a long time.[3] Electric propulsion can achieve high speeds over long periods and thus can work better than chemical rockets for some deep space missions.[2] Electric propulsion is now a mature and widely used technology on spacecraft. History[edit] Types[edit] Ion thruster.
Spacecraft engine that generates thrust by generating a jet of ions NEXIS ion engine test (2005) A prototype of a xenon ion engine being tested at NASA's Jet Propulsion Laboratory An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. Ion thrusters are categorized as either electrostatic or electromagnetic.
Electrostatic thruster ions are accelerated by the Coulomb force along the electric field direction. By contrast, electromagnetic thruster ions are accelerated by the Lorentz force to accelerate all species (free electrons as well as positive and negative ions) in the same direction whatever their electric charge, and are specifically referred to as plasma propulsion engines, where the electric field is not in the direction of the acceleration.[1][2] Origins[edit] Moon. Natural satellite orbiting the Earth Both the Moon's prominence in Earth's sky and its regular cycle of phases have provided cultural references and influences for human societies throughout history. Such influences can be found in language, calendar systems, art, and mythology. The first artificial object to reach the Moon was the Soviet Union's uncrewed Luna 2 spacecraft in 1959; this was followed by the first successful soft landing by Luna 9 in 1966.
The only human lunar missions to date have been those of the United States' Apollo program, which landed twelve men on the surface between 1969 and 1972. Names and etymology The usual English adjective pertaining to the Moon is "lunar", derived from the Latin word for the Moon, lūna. The astronomical symbol for the Moon is a crescent, , for example in M☾ 'lunar mass' (also ML). Natural history Lunar geologic timescale Millions of years before present Formation Giant impacts are thought to have been common in the early Solar System.
Structure. Molybdenum. Chemical element with atomic number 42 Chemical element, symbol Mo and atomic number 42 Molybdenum does not occur naturally as a free metal on Earth; it is found only in various oxidation states in minerals. The free element, a silvery metal with a grey cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys, and for this reason most of the world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Most molybdenum compounds have low solubility in water, but when molybdenum-bearing minerals contact oxygen and water, the resulting molybdate ion MoO2−4 is quite soluble. Industrially, molybdenum compounds (about 14% of world production of the element) are used in high-pressure and high-temperature applications as pigments and catalysts. Characteristics[edit] Physical properties[edit] Chemical properties[edit] Gaseous molybdenum consists of the diatomic species Mo2.
Isotopes[edit] Eclipse. Astronomical event where one body is hidden by another Totality during the 1999 solar eclipse. Solar prominences can be seen along the limb (in red) as well as extensive coronal filaments. The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the Moon moves into the Earth's shadow.
However, it can also refer to such events beyond the Earth–Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon. A binary star system can also produce eclipses if the plane of the orbit of its constituent stars intersects the observer's position. For the special cases of solar and lunar eclipses, these only happen during an "eclipse season", the two times of each year when the plane of the Earth's orbit around the Sun crosses with the plane of the Moon's orbit around the Earth.