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Journey To Enceladus And Titan
Journey to Enceladus and Titan (JET) is an astrobiology mission concept to assess the planetary habitability, habitability potential of Enceladus and Titan (moon), Titan, moons of Saturn. The JET orbiter concept was proposed in 2011 by the Jet Propulsion Laboratory to NASA's Discovery Program for its 13th mission, but it was not selected as a semi-finalist; Lucy (spacecraft), Lucy was selected on January 4, 2017. Concept Enceladus is a small icy moon, seemingly similar in chemical makeup to comets, with jets or geysers of water erupting from its surface that might be connected to active hydrothermal vents at its subsurface water ocean floor, where the moon's ocean meets the underlying rock, a prime habitat for life. The geysers could provide easy access for sampling the moon's subsurface ocean, and if there is Microorganism, microbial life in it, ice particles from the sea could contain the evidence astrobiologists need to identify them. An Organic compound, organic-rich world, Ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrobiology
Astrobiology (also xenology or exobiology) is a scientific field within the List of life sciences, life and environmental sciences that studies the abiogenesis, origins, Protocell, early evolution, distribution, and future of life in the universe by investigating its deterministic conditions and contingent events. As a discipline, astrobiology is founded on the premise that life may exist beyond Earth. Research in astrobiology comprises three main areas: the study of planetary habitability, habitable environments in the Solar System and beyond, the search for planetary biosignatures of past or present extraterrestrial life, and the study of the Abiogenesis, origin and Protocell, early evolution of life on Earth. The field of astrobiology has its origins in the 20th century with the advent of space exploration and the discovery of exoplanets. Early astrobiology research focused on the search for extraterrestrial life and the study of the potential for life to exist on other pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Life
Life, also known as biota, refers to matter that has biological processes, such as Cell signaling, signaling and self-sustaining processes. It is defined descriptively by the capacity for homeostasis, Structure#Biological, organisation, metabolism, Cell growth, growth, adaptation, response to stimulus (physiology), stimuli, and reproduction. All life over time eventually reaches a state of death, and none is Immortality, immortal. Many philosophical definitions of living systems have been proposed, such as self-organizing systems. Viruses in particular make definition difficult as they replicate only in Host (biology), host cells. Life exists all over the Earth in air, water, and soil, with many ecosystems forming the biosphere. Some of these are harsh environments occupied only by extremophiles. Life has been studied since ancient times, with theories such as Empedocles's materialism asserting that it was composed of Classical element, four eternal elements, and Aristotle's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Assist
A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby (spaceflight), flyby which makes use of the relative movement (e.g. orbit around the Sun) and gravity of a planet or other astronomical object to alter the Course (navigation), path and speed of a spacecraft, typically to save propellant and reduce expense. Gravity assistance can be used to accelerate a spacecraft, that is, to increase or decrease its speed or redirect its path. The "assist" is provided by the motion of the gravitating body as it pulls on the spacecraft. Any gain or loss of kinetic energy and linear momentum by a passing spacecraft is correspondingly lost or gained by the gravitational body, in accordance with Newton's laws of motion#Newton's third law, Newton's Third Law. The gravity assist maneuver was first used in 1959 when the Soviet probe Luna 3 photographed the far side of Earth's Moon, and it was used by inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California Institute Of Technology
The California Institute of Technology (branded as Caltech) is a private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small group of institutes of technology in the United States that are devoted to the instruction of pure and applied sciences. The institution was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910, and the college assumed its present name in 1920. In 1934, Caltech was elected to the Association of American Universities, and the antecedents of NASA's Jet Propulsion Laboratory, which Caltech continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán. Caltech has six academic divisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrobiology
Astrobiology (also xenology or exobiology) is a scientific field within the List of life sciences, life and environmental sciences that studies the abiogenesis, origins, Protocell, early evolution, distribution, and future of life in the universe by investigating its deterministic conditions and contingent events. As a discipline, astrobiology is founded on the premise that life may exist beyond Earth. Research in astrobiology comprises three main areas: the study of planetary habitability, habitable environments in the Solar System and beyond, the search for planetary biosignatures of past or present extraterrestrial life, and the study of the Abiogenesis, origin and Protocell, early evolution of life on Earth. The field of astrobiology has its origins in the 20th century with the advent of space exploration and the discovery of exoplanets. Early astrobiology research focused on the search for extraterrestrial life and the study of the potential for life to exist on other pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specular Spectacular (PIA18432)
Specular reflection, or regular reflection, is the mirror-like reflection of waves, such as light, from a surface. The law of reflection states that a reflected ray of light emerges from the reflecting surface at the same angle to the surface normal as the incident ray, but on the opposing side of the surface normal in the plane formed by the incident and reflected rays. The earliest known description of this behavior was recorded by Hero of Alexandria ( AD c. 10–70). Later, Alhazen gave a complete statement of the law of reflection. He was first to state that the incident ray, the reflected ray, and the normal to the surface all lie in a same plane perpendicular to reflecting plane. Specular reflection may be contrasted with diffuse reflection, in which light is scattered away from the surface in a range of directions. Law of reflection When light encounters a boundary of a material, it is affected by the optical and electronic response functions of the material to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturn
Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 times more massive. Even though Saturn is almost as big as Jupiter, Saturn has less than a third its mass. Saturn orbits the Sun at a distance of , with an orbital period of 29.45 years. Saturn's interior is thought to be composed of a rocky core, surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and an outer layer of gas. Saturn has a pale yellow hue, due to ammonia crystals in its upper atmosphere. An electrical current in the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth because of Saturn's greater size. Saturn's magnetic field strength is about a twen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Spectroscopy
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a type of plot of the ion signal as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. In a typical MS procedure, a sample, which may be solid, liquid, or gaseous, is ionized, for example by bombarding it with a beam of electrons. This may cause some of the sample's molecules to break up into positively charged fragments or simply become positively charged without fragmenting. These ions (fragments) are then separated accordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar And Planetary Institute
The Lunar and Planetary Institute (LPI) is a scientific research institute dedicated to study of the Solar System, its formation, evolution, and current state. The Institute is part of the Universities Space Research Association (USRA) and is supported by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). Located at 3600 Bay Area Boulevard in Houston, Texas, the Institute serves as a scientific forum attracting visiting scientists, postdoctoral fellows, students, and resident experts; supports and serves the research community through newsletters, meetings, and other activities; collects and disseminates planetary data while facilitating the community's access to NASA astromaterials samples and facilities; engages and excites the public about space science; and invests in the development of future generations of scientists. The LPI sponsors and organizes several workshops and conferences throughout the year, including the Lunar and Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enceladus Geysers June 2009
Enceladus is the sixth-largest moon of Saturn and the 18th-largest in the Solar System. It is about in diameter, about a tenth of that of Saturn's largest moon, Titan (moon), Titan. It is covered by clean, freshly deposited snow hundreds of meters thick, making it one of the most reflective bodies of the Solar System. Consequently, its surface temperature at noon reaches only , far colder than a light-absorbing body would be. Despite its small size, Enceladus has a wide variety of surface features, ranging from old, heavily impact crater, cratered regions to young, Tectonics, tectonically deformed terrain. Enceladus was discovered on August 28, 1789, by William Herschel, but little was known about it until the two Voyager program, Voyager spacecraft, ''Voyager 1'' and ''Voyager 2'', flew by Saturn in 1980 and 1981. In 2005, the spacecraft ''Cassini–Huygens, Cassini'' started multiple close flybys of Enceladus, revealing its surface and environment in greater detail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it is difficult because it is a gas at standard temperature and pressure. In the Earth's atmosphere methane is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. Methane is an Organic chemistry, organic Organic compound, compound, and among the simplest of organic compounds. Methane is also a hydrocarbon. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the Atmosphere of Earth, atmosphere, it is known as atmospheric methane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
