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Luyten's Star
Luyten's Star (GJ 273) is a red dwarf in the constellation Canis Minor located at a distance of from the Sun. It has a visual magnitude of 9.9, making it too faint to be viewed with the unaided eye. It is named after Willem Jacob Luyten, who, in collaboration with Edwin G. Ebbighausen, first determined its high proper motion in 1935. The star has two confirmed planets and two candidate planets, of which Luyten b is in the circumstellar habitable zone. Properties This star is approximately a quarter the mass of the Sun and has 35% of the Sun's radius. Luyten's Star is at the maximum mass at which a red dwarf can be fully convective, which means that most if not all of the star forms an extended convection zone. It has a stellar classification of M3.5V, with the V luminosity class indicating this is a main-sequence star that is generating energy through the thermonuclear fusion of hydrogen at its core. The projected rotation rate of this star is too low to be measu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canis Minor
Canis Minor is a small constellation in the Celestial sphere, northern celestial hemisphere. In the second century, it was included as an Asterism (astronomy), asterism, or pattern, of two stars in Ptolemy's 48 constellations, and it is counted among the Lists of constellations, 88 modern constellations. Its name is Latin for "lesser dog", in contrast to Canis Major, the "greater dog"; both figures are commonly represented as following the constellation of Orion (constellation), Orion the hunter. Canis Minor contains only two stars brighter than the fourth apparent magnitude, magnitude, Procyon (Alpha Canis Minoris), with a magnitude of 0.34, and Gomeisa (Beta Canis Minoris), with a magnitude of 2.9. The constellation's dimmer stars were noted by Johann Bayer, who named eight stars including Alpha and Beta, and John Flamsteed, who numbered fourteen. Procyon is the List of brightest stars, eighth-brightest star in the night sky, as well as one of the List of nearest stars, close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-type Star
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with spectral lines. Each line indicates a particular chemical element or molecule, with the line strength indicating the abundance of that element. The strengths of the different spectral lines vary mainly due to the temperature of the photosphere, although in some cases there are true abundance differences. The ''spectral class'' of a star is a short code primarily summarizing the ionization state, giving an objective measure of the photosphere's temperature. Most stars are currently classified under the Morgan–Keenan (MK) system using the letters ''O'', ''B'', ''A'', ''F'', ''G'', ''K'', and ''M'', a sequence from the hottest (''O'' type) to the coolest (''M'' type). Each letter class is then subdivided ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barcelona
Barcelona ( ; ; ) is a city on the northeastern coast of Spain. It is the capital and largest city of the autonomous community of Catalonia, as well as the second-most populous municipality of Spain. With a population of 1.6 million within city limits,Barcelona: Población por municipios y sexo – Instituto Nacional de Estadística. (National Statistics Institute) its urban area extends to numerous neighbouring municipalities within the province of Barcelona and is home to around 5.3 million people, making it the fifth most populous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
METI (Messaging Extraterrestrial Intelligence)
METI International, known simply as METI, is a non-profit research organization founded in July 2015 by Douglas Vakoch that creates and transmits interstellar messages to attempt to communicate with extraterrestrial civilizations. It is based in San Francisco, California. Overview METI targets nearby stars and researches the nature of the messages to send. On October 16, 17, and 18, 2017, it sent a message consisting of a scientific and mathematical tutorial to the red dwarf Luyten's Star, just over 12 light years from Earth. The message was sent from a radio transmitter at the EISCAT research facility in Tromsø, Norway. METI's aim is to build an interdisciplinary community to design interstellar messages, within the context of the evolution of intelligence and language. In May 2016, it convened the meeting “The Intelligence Of SETI: Cognition And Communication In Extraterrestrial Intelligence” in Puerto Rico. In May 2018 in Los Angeles, it held “Language in the Cosmos� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sónar
Sónar is a festival dedicated to music, creativity and technology, founded in Barcelona in 1994 by Ricard Robles, Enric Palau, and Sergi Caballero. The festival has been divided into two parts since its inception: Sónar by Day and Sónar by Night, with a three-day congress, Sónar+D dedicated to Creativity, Technology and Business running concurrently since 2013. As well as the flagship event in Barcelona, Sónar hosts events around the world, with annual festivals having taken place in Bogota, Buenos Aires, Hong Kong and Reykjavik. In 2023, the 30th anniversary of the festival was held in Barcelona, along with Sónar festivals in Lisbon (for the 2nd time) and Istanbul (7th time). Artists that have performed at Sónar include Björk, Thom Yorke, Jean-Michel Jarre, Duran Duran, Grace Jones, Beastie Boys, De La Soul, Kraftwerk, Gorillaz, New Order, Skrillex, Diplo, M.I.A., Arca, Rosalía, Yo La Tengo, Chic, Ryuichi Sakamoto, Aphex Twin, Richie Hawtin and Laurent Garni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRAPPIST-1
, - ! style="background-color: #FFFFC0; text-align: center;" colspan="2", Characteristics , - style="vertical-align:top" ! style="text-align:left" , Evolutionary stage , Main sequence , - style="vertical-align:top" ! style="text-align:left" , Spectral type , M8V , - style="vertical-align:top" ! style="text-align:left" , Apparent magnitude (R) , , - style="vertical-align:top" ! style="text-align:left" , Apparent magnitude (I) , , - style="vertical-align:top" ! style="text-align:left" , Apparent magnitude (J) , , - style="vertical-align:top" ! style="text-align:left" , Apparent magnitude (H) , , - style="vertical-align:top" ! style="text-align:left" , Apparent magnitude (K) , , - style="vertical-align:top" ! style="text-align:left" , V−R , 2.332 , - style="vertical-align:top" ! style="text-align:left" , R−I , 2.442 , - style="vertical-align:top" ! style="text-align:left" , J−H , 0.63 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibrium Temperature
The planetary equilibrium temperature is a theoretical temperature that a planet would be if it were in radiative equilibrium, typically under the assumption that it radiates as a black body being heated only by its parent star. In this model, the presence or absence of an atmosphere (and therefore any greenhouse effect) is irrelevant, as the equilibrium temperature is calculated purely from a balance with incident stellar energy. Other authors use different names for this concept, such as equivalent blackbody temperature of a planet. The effective radiation emission temperature is a related concept, but focuses on the actual power radiated rather than on the power being received, and so may have a different value if the planet has an internal energy source or when the planet is not in radiative equilibrium. Planetary equilibrium temperature differs from the global mean temperature and surface air temperature, which are measured observationally by satellites or surface-based i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Mass
An Earth mass (denoted as ''M''🜨, ''M''♁ or ''M''E, where 🜨 and ♁ are the astronomical symbols for Earth), is a unit of mass equal to the mass of the planet Earth. The current best estimate for the mass of Earth is , with a relative uncertainty of 10−4.The cited value is the recommended value published by the International Astronomical Union in 2009 (se2016 "Selected Astronomical Constants" in ). It is equivalent to an average density of . Using the nearest metric prefix, the Earth mass is approximately six ronnagrams, or 6.0 Rg. The Earth mass is a standard unit of mass in astronomy that is used to indicate the masses of other planets, including rocky terrestrial planets and exoplanets. One Solar mass is close to Earth masses. The Earth mass excludes the mass of the Moon. The mass of the Moon is about 1.2% of that of the Earth, so that the mass of the Earth–Moon system is close to . Most of the mass is accounted for by iron and oxygen (c. 32% each), m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimum Mass
In astronomy, minimum mass is the lower-bound calculated mass of observed objects such as planets, stars, binary systems, nebulae, and black holes. Minimum mass is a widely cited statistic for extrasolar planets detected by the radial velocity method or Doppler spectroscopy, and is determined using the binary mass function. This method reveals planets by measuring changes in the movement of stars in the line-of-sight, so the real orbital inclinations and true masses of the planets are generally unknown. This is a result of sin ''i'' degeneracy. If inclination ''i'' can be determined, the true mass can be obtained from the calculated minimum mass using the following relationship: M_\text = \frac Exoplanets Orientation of the transit to Earth Most stars will not have their planets lined up and orientated so that they eclipse over the center of the star and give the viewer on earth a perfect transit. It is for this reason that when we often are only able to extrapolate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitable Zone
In astronomy and astrobiology, the habitable zone (HZ), or more precisely the circumstellar habitable zone (CHZ), is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.J. F. Kasting, D. P. Whitmire, R. T. Reynolds, Icarus 101, 108 (1993). The bounds of the HZ are based on Earth's position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to Earth's biosphere, the nature of the HZ and the objects within it may be instrumental in determining the scope and distribution of planets capable of supporting Earth-like extraterrestrial life and extraterrestrial intelligence, intelligence. As such, it is considered by many to be a major factor of planetary habitability, and the most likely place to find extraterrestrial liquid water and biosignatures elsewhere in the universe. The habitable zone is also called the Goldilocks zone, a metaphor, all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super-Earth
A super-Earth is a type of exoplanet with a mass higher than Earth, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17.1 times Earth's, respectively. The term "super-Earth" refers only to the mass of the planet, and so does not imply anything about the surface conditions or Planetary habitability, habitability. The alternative term "gas dwarfs" may be more accurate for those at the higher end of the mass scale, although "mini-Neptunes" is a more common term. Definition In general, super-Earths are defined by their masses. The term does not imply temperatures, compositions, orbital properties, habitability, or environments. While sources generally agree on an upper bound of 10 Earth masses (~69% of the mass of Uranus, which is the Solar System's giant planet with the least mass), the lower bound varies from 1 or 1.9 to 5, with various other definitions appearing in the popular media. The term "super-Earth" is also used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Velocity (astronomy)
In astronomy, stellar kinematics is the Observational astronomy, observational study or measurement of the kinematics or motions of stars through space. Stellar kinematics encompasses the measurement of stellar Velocity, velocities in the Milky Way and its Satellite galaxies of the Milky Way, satellites as well as the internal kinematics of more distant Galaxy, galaxies. Measurement of the kinematics of stars in different subcomponents of the Milky Way including the thin disk, the thick disk, the Bulge (astronomy), bulge, and the stellar halo provides important information about the formation and evolutionary history of our Galaxy. Kinematic measurements can also identify exotic phenomena such as hypervelocity stars escaping from the Milky Way, which are interpreted as the result of gravitational encounters of binary stars with the Sagittarius A*, supermassive black hole at the Galactic Center. Stellar kinematics is related to but distinct from the subject of stellar dynamics, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
