Vega / Launch vehicles / Launchers / Our Activities / ESAVega VV0. IXV Liftoff. Vega is designed to cope with a wide range of missions and payload configurations in order to respond to different market opportunities. In particular, it offers configurations able to handle payloads ranging from a single satellite up to one main satellite plus additional small satellites. Vega is benchmarked to loft 1. It is the ideal launcher for most scientific and Earth observation missions. It operates from Europe’s Spaceport in Kourou, French Guiana. It has three solid- propellant stages and a liquid- propellant upper module for attitude and orbit control, and satellite release. Vega is still early-stage software. We're working on many exciting features for our upcoming release and would like to keep you notified when it. KapanLagi.com: Vega Darmawanti: Download koleksi foto dan videonya. Vega Darmawanti Cemburu Dengan Kedekatan Shaheer & Ayu Ting Ting, Kena Banjir, Vega Darmawanti. Vega, also designated Alpha Lyrae ( Live your best life with clean, plant-based nutrition. Join us: #BestLifeProject. Vega is designed to cope with a wide range of missions and payload configurations in order to respond to different market opportunities. Unlike most small launchers. VEGA is a globally active manufacturer of process measurement technology. VEGA’s product portfolio extends from sensors for measuring level, limit level and pressure. Vega is a simple, clean, minimal, responsive one page business WordPress theme. It can be used for a personal blog or a business website. Using Vega to create your. Good for your body and the planet, Vega is the clean, plant-based choice to fuel your healthy, active lifestyle—without compromise. This lowered costs mainly by speeding up the launch campaign. Vega - Wikipedia. Vega. Observation data. Epoch. J2. 00. 0. Equinox. J2. 00. 0. Constellation. Lyra. Pronunciationor Right ascension. It is relatively close at only 2. Sun, and, together with Arcturus and Sirius, one of the most luminous stars in the Sun's neighborhood. Vega has been extensively studied by astronomers, leading it to be termed .
Vega has served as the baseline for calibrating the photometric brightness scale, and was one of the stars used to define the mean values for the UBV photometric system. Vega is only about a tenth of the age of the Sun, but since it is 2. Sun; both stars are at present approaching the midpoint of their life expectancies. Vega has an unusually low abundance of the elements with a higher atomic number than that of helium. It is rotating rapidly with a velocity of 2. This is causing the equator to bulge outward because of centrifugal effects, and, as a result, there is a variation of temperature across the star's photosphere that reaches a maximum at the poles. From Earth, Vega is being observed from the direction of one of these poles. This dust is likely to be the result of collisions between objects in an orbiting debris disk, which is analogous to the Kuiper belt in the Solar System. The traditional name Vega (earlier Wega. The WGSN's first bulletin of July 2. It is now so entered in the IAU Catalog of Star Names. On July 1. 7, 1. 85. Vega became the first star (other than the Sun) to be photographed, when it was imaged by William Bond and John Adams Whipple at the Harvard College Observatory, also with a daguerreotype. These were later identified as lines from the Hydrogen Balmer series. The first person to publish a star's parallax was Friedrich G. This change cast further doubt on Struve's data. Thus most astronomers at the time, including Struve, credited Bessel with the first published parallax result. However, Struve's initial result was actually close to the currently accepted value of 0. This apparent magnitude is a numerical value that decreases in value with increasing brightness of the star. The faintest stars visible to the unaided eye are sixth magnitude, while the brightest, Sirius, is of magnitude . To standardize the magnitude scale, astronomers chose Vega to represent magnitude zero at all wavelengths. Thus, for many years, Vega was used as a baseline for the calibration of absolute photometric brightness scales. This approach is more convenient for astronomers, since Vega is not always available for calibration. Vega is one of six A0. V stars that were used to set the initial mean values for this photometric system when it was introduced in the 1. The mean magnitudes for these six stars were defined as: U . In effect, the magnitude scale has been calibrated so that the magnitude of these stars is the same in the yellow, blue, and ultraviolet parts of the electromagnetic spectrum. This range of variability was near the limits of observational capability for that time, and so the subject of Vega's variability has been controversial. The magnitude of Vega was measured again in 1. David Dunlap Observatory and showed some slight variability. Thus it was suggested that Vega showed occasional low- amplitude pulsations associated with a Delta Scuti variable. Thus the variability was thought to possibly be the result of systematic errors in measurement. The Infrared Astronomical Satellite (IRAS) discovered an excess of infrared radiation coming from the star, and this was attributed to energy emitted by the orbiting dust as it was heated by the star. With a declination of +3. Therefore, it does not rise at all anywhere in Antarctica or in the southernmost part of South America, including Punta Arenas, Chile (5. At latitudes to the north of +5. Around July 1, Vega reaches midnight culmination when it crosses the meridian at that time. The Summer Triangle is recognizable in the northern skies for there are few other bright stars in its vicinity. Since more massive stars use their fusion fuel more quickly than smaller ones, Vega's main- sequence lifetime is roughly one billion years, a tenth of the Sun's. After leaving the main sequence, Vega will become a class- M red giant and shed much of its mass, finally becoming a white dwarf. At present, Vega has more than twice the mass. However, because of its high rate of rotation, the pole is considerably brighter than the equator. Because it is seen nearly pole- on, its apparent luminosity from Earth is notably higher, about 5. Sun's value. This process requires a temperature of about 1. K. The CNO cycle is highly temperature sensitive, which results in a convection zone about the core. The overlying atmosphere is in radiative equilibrium. This is in contrast to the Sun, which has a radiation zone centered on the core with an overlying convection zone. This is the first such detection of a magnetic field on a spectral class A star that is not an Apchemically peculiar star. The average line of sight component of this field has a strength of . This is 6. 0% larger than the radius of the star Sirius, while stellar models indicated it should only be about 1. However, this discrepancy can be explained if Vega is a rapidly rotating star that is being viewed from the direction of its pole of rotation. Observations by the CHARA array in 2. At the high end of estimates for the rotation velocity for Vega is 2. This is seen as a variation in effective temperature over the star: the polar temperature is near 1. K, while the equatorial temperature is 7,6. K. As viewed from the poles, this results in a darker (lower intensity) limb than would normally be expected for a spherically symmetric star. The temperature gradient may also mean Vega has a convection zone around the equator. With the viewing angle and rotation rate of Vega now better known, this will allow for improved instrument calibrations. The metallicity of Vega's photosphere is only about 3. Sun's atmosphere. One possibility is that the chemical peculiarity may be the result of diffusion or mass loss, although stellar models show that this would normally only occur near the end of a star's hydrogen- burning lifespan. Another possibility is that the star formed from an interstellar medium of gas and dust that was unusually metal- poor. This may be caused by the disappearance of a helium convection zone near the surface. Energy transfer is instead performed by the radiative process, which may be causing an abundance anomaly through diffusion. Movement away from the Earth will cause the light from Vega to shift to a lower frequency (toward the red), or to a higher frequency (toward the blue) if the motion is toward the Earth. Thus the velocity can be measured from the amount of redshift (or blueshift) of the star's spectrum. Precise measurements of this redshift give a value of . Careful measurement of the star's position allows this angular movement, known as proper motion, to be calculated. Vega's proper motion is 2. The net proper motion of Vega is 3. Although Vega is at present only the fifth- brightest star in the sky, the star is slowly brightening as proper motion causes it to approach the Sun. However, Vega may be much older than this group, so the membership remains uncertain. All members of the group are moving in nearly the same direction with similar space velocities. Membership in a moving group implies a common origin for these stars in an open cluster that has since become gravitationally unbound. This excess was measured at wavelengths of 2. At the measured distance of Vega, this corresponded to an actual radius of 8. AU), where an AU is the average radius of the Earth's orbit around the Sun. It was proposed that this radiation came from a field of orbiting particles with a dimension on the order of a millimeter, as anything smaller would eventually be removed from the system by radiation pressure or drawn into the star by means of Poynting. This effect is most pronounced for tiny particles that are closer to the star. To maintain this amount of dust in orbit around Vega, a continual source of replenishment would be required. A proposed mechanism for maintaining the dust was a disk of coalesced bodies that were in the process of collapsing to form a planet. In addition, there is a hole in the center of the disk with a radius of no less than 8. AU. As of 2. 00. 2, about 4. It is believed that these may provide clues to the origin of the Solar System. It was shown to extend out to 4. These much wider disks were found to be circular and free of clumps, with dust particles ranging from 1. The estimated total mass of this dust is 3. Production of the dust would require collisions between asteroids in a population corresponding to the Kuiper Belt around the Sun. Thus the dust is more likely created by a debris disk around Vega, rather than from a protoplanetary disk as was earlier thought. The disk of dust is produced as radiation pressure from Vega pushes debris from collisions of larger objects outward. However, continuous production of the amount of dust observed over the course of Vega's lifetime would require an enormous starting mass. Hence it is more likely to have been produced as the result of a relatively recent breakup of a moderate- sized (or larger) comet or asteroid, which then further fragmented as the result of collisions between the smaller components and other bodies. This dusty disk would be relatively young on the time scale of the star's age, and it will eventually be removed unless other collision events supply more dust. Wilson in 2. 00. 6 and the Infrared Optical Telescope Array at Mt. Originating within 8 AU of the star, this exozodiacal dust may be evidence of dynamical perturbations within the system. This was hypothesized as either a perturbation of the dust disk by a planet or else an orbiting object that was surrounded by dust. However, images by the Keck telescope had ruled out a companion down to magnitude 1. Jupiter. Dust would collect in orbits that have mean- motion resonances with this planet.
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