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42) Republic Day 2021: Parade right time to security arrangements traffic prohibitions to Delhi Metro expert services - All you need to know

India Republic Day -- Republic Day 2021 Parade Schedule Chief Guest Security Agreements: The parade normally sees thousands of people and foreign dignitaries invited to see the parade. Nonetheless the number of guests and guests has been restricted due to the coronavirus pandemic this time. Republic Time 2021 Parade Timings Chief Guest Delhi Metro Services : India will celebrate its 72nd Republic Day on January 26. This day is marked to celebrate the day on which the Constitution regarding India came into being in 1950. On this day the Republic Day parade takes place to show off the military might and the rich cultural heritage in the country. The parade commonly sees thousands of people and foreign dignitaries invited to see the celebration. However the number of guests along with attendees has been restricted as a result of coronavirus pandemic this time. This year there will be no chief invitees or foreign dignitaries on Republic Day. The number of race fans has also been brought...
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Proxima Centauri b

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Proxima Centauri b (also called Proxima b or Alpha Centauri Cb ) is an exoplanet orbiting in the habitable zone of the red dwarf star Proxima Centauri, which is the closest star to the Sun and part of a triple star system. It is located approximately 4.2 light-years (4.0 × 1013 km) from Earth in the constellation of Centaurus, making it and Proxima c the closest known exoplanets to the Solar System. Proxima Centauri b orbits the star at a distance of roughly 0.05 AU (7,500,000 km; 4,600,000 mi) with an orbital period of approximately 11.2 Earth days, and has an estimated mass of at least 1.2 times that of the Earth. The planet is subject to stellar wind pressures of more than 2,000 times those experienced by Earth from the solar wind and the habitability of Proxima Centauri b has not yet been definitively established. The discovery of the planet was announced in August 2016. The planet was found using the radial velocity method, where periodic Doppler shifts of spectral lines of th...
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Physical characteristics

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Mass, radius, and temperature edit The apparent inclination of Proxima Centauri b's orbit has not yet been measured. The minimum mass of Proxima b is 1.17  M ⊕ , which would be the actual mass if its orbit were seen edge on from the Earth. Once its orbital inclination is known, the mass will be calculable. More tilted orientations imply a higher mass, with 90% of possible orientations implying a mass below 2.77  M ⊕ . The planet's exact radius is unknown. If it has a rocky composition and a density equal to that of the Earth, then its radius is at least 1.1  R ⊕ . It could be larger if it has a lower density than the Earth, or a mass higher than the minimum mass. Like many super-Earth sized planets, Proxima Centauri b might have an icy composition like Neptune, with a thick enveloping, hydrogen and helium atmosphere; the likelihood that this is the case has been calculated to be greater than 10%. The planet has an equilibrium temperature of 234 K (−39 °C; −38 °F), somewhat cold...
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Habitability

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The habitability of Proxima Centauri b has not been established, but the planet is subject to stellar wind pressures of more than 2,000 times those experienced by Earth from the solar wind. This radiation and the stellar winds would likely blow any atmosphere away, leaving the subsurface as the only potentially habitable location on that planet. The exoplanet is orbiting within the habitable zone of Proxima Centauri, the region where, with the correct planetary conditions and atmospheric properties, liquid water may exist on the surface of the planet. The host star, with about an eighth of the mass of the Sun, has a habitable zone between ∼0.0423–0.0816 AU. In October 2016, researchers at France's CNRS research institute stated that there is a considerable chance of the planet harboring surface oceans and having a thin atmosphere. However, unless the planet transits in front of its star from the perspective of Earth, it is difficult to test these hypotheses. Even though Proxima Cen...
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View from Proxima Centauri b

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Viewed from near the Alpha Centauri system, the sky would appear much as it does for an observer on Earth, except that Centaurus would be missing its brightest star. The Sun would be a yellow star of an apparent magnitude of +0.5 in eastern Cassiopeia, at the antipodal point of Alpha Centauri's current right ascension and declination, at 02h 39m 35s +60° 50′ (2000). This place is close to the 3.4-magnitude star ε Cassiopeiae. Because of the placement of the Sun, an interstellar or alien observer would find the \/\/ of Cassiopeia had become a /\/\/ shapenote nearly in front of the Heart Nebula in Cassiopeia. Sirius lies less than a degree from Betelgeuse in the otherwise unmodified Orion and with a magnitude of −1.2 is a little fainter than from Earth but still the brightest star in the Alpha Centauri sky. Procyon is also displaced into the middle of Gemini, outshining Pollux, whereas both Vega and Altair are shifted northwestward relative to Deneb (which barely moves, due to its ...
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Formation

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It is unlikely that Proxima Centauri b originally formed in its current orbit since disk models for small stars like Proxima Centauri would contain less than one Earth mass  M ⊕ of matter within the central one AU at the time of their formation. This implies that either Proxima Centauri b was formed elsewhere in a manner still to be determined, or the current disc models for stellar formation are in need of revision.
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Discovery

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The first indications of the exoplanet were found in 2013 by Mikko Tuomi of the University of Hertfordshire from archival observation data. To confirm the possible discovery, a team of astronomers launched the Pale Red Dotnote project in January 2016. On 24 August 2016, the team of 31 scientists from all around the world, led by Guillem Anglada-Escudé of Queen Mary University of London, confirmed the existence of Proxima Centauri b through their research, published in a peer-reviewed article in Nature . The measurements were done using two spectrographs, HARPS on the ESO 3.6 m Telescope at La Silla Observatory and UVES on the 8-metre Very Large Telescope. The peak radial velocity of the host star combined with the orbital period allowed for the minimum mass of the exoplanet to be calculated. The chance of a false positive detection is less than one in ten million. Observational complications of the star tend to indicate additional, not insignificant size, orbiting planets. Another sup...
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